Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

The following discussion contains forward-looking statements that involve risks and uncertainties. Our actual results could differ materially from those discussed here. Factors that could cause or contribute to such differences include, but are not limited to, those discussed in this section as well as factors described in “Part I, Item 1A — Risk Factors.”

Overview

Strategic Direction of Our Business

Nektar Therapeutics is a clinical stage, research-based drug discovery biopharmaceutical company focused on discovering and developing innovative medicines in the field of immunotherapy. Within this growing field, we direct our efforts toward creating new immunomodulatory agents that selectively induce, amplify, attenuate or prevent immune responses in order to achieve desired therapeutic outcomes. We apply our deep understanding of immunology to identify and create innovative drug candidates and use our drug development expertise to advance these molecules through preclinical and clinical development. Our pipeline of clinical-stage and preclinical-stage immunomodulatory agents targets the treatment of autoimmune diseases (e.g., rezpegaldesleukin and NKTR-0165, respectively) and cancer (e.g., NKTR-255). We continue to make significant investments in building and advancing our pipeline of drug candidates as we believe that this is the best strategy to build long-term shareholder value.

Autoimmune and inflammatory diseases cause the immune system to mistakenly attack and damage healthy cells in a person’s body. A failure of the body’s self-tolerance mechanisms enables the formation of the pathogenic T lymphocytes that conduct this attack. Our drug candidate rezpegaldesleukin is a potential first-in-class resolution therapeutic that may address this underlying immune system imbalance in people with autoimmune disorders and inflammatory diseases. It is designed to target the interleukin-2 (IL-2) receptor complex in the body in order to stimulate proliferation of powerful inhibitory immune cells known as regulatory T cells (Treg cells). Describing the critical role of Treg cells in maintaining balance in the immune system earned Drs. Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi, the Nobel Prize in medicine on October 6, 2025. By activating these Treg cells, rezpegaldesleukin may act to bring the immune system back into balance. Rezpegaldesleukin is being developed as a once or twice monthly self-administered injection for a number of autoimmune disorders and inflammatory diseases.

In late October 2023, we initiated a Phase 2b clinical study of rezpegaldesleukin in patients with moderate-to-severe atopic dermatitis (the Phase 2b RESOLVE-AD trial). On February 11, 2025, we announced that the FDA had granted Fast Track designation for rezpegaldesleukin for the treatment of adult and pediatric patients 12 years of age and older with moderate-to-severe atopic dermatitis whose disease is not adequately controlled with topical prescription therapies or when those therapies are not advisable. In March 2024, we initiated a Phase 2b clinical study in patients with severe-to-very severe alopecia areata (the Phase 2b RESOLVE-AA trial). On July 29, 2025, we announced that the FDA had granted Fast Track designation for rezpegaldesleukin for the treatment of severe-to-very severe alopecia areata in adult and pediatric patients 12 years of age and older who weigh at least 40 kg. On February 24, 2025, we announced that we had entered into a collaboration agreement with TrialNet to evaluate rezpegaldesleukin in patients with new onset stage 3 type 1 diabetes mellitus in a Phase 2 study. TrialNet will conduct the study with funding from the National Institutes of Health, primarily through the Special Statutory Funding Program for Type 1 Diabetes through the National Institute of Diabetes and Digestive and Kidney Diseases. Nektar will supply rezpegaldesleukin for the study and will retain all rights to the rezpegaldesleukin program under the collaboration.

On June 24, 2025, we announced statistically significant data from the 16-week induction period of the ongoing Phase 2b REZOLVE-AD trial being conducted in 393 patients. In the trial, patients were randomized (3:3:3:2) to receive subcutaneous treatment with one of three doses of rezpegaldesleukin: a high dose of 24 μg/kg every two weeks (q2w), a middle dose of 18 μg/kg q2w, and a low dose of 24 μg/kg every four weeks (q4w), or placebo q2w. The primary endpoint and secondary endpoints were assessed at week 16. Following the 16-week induction period, rezpegaldesleukin-treated patients who achieved Eczema Area and Severity Score (EASI) percent score reductions of >50 were re-randomized (1:1) to continue at the same dose level on a q4w or q12w regimen through week 52 in a blinded maintenance period. Placebo patients with EASI percent score reductions of >50 percent continue to receive placebo q4w.

As announced on June 24, 2025, the Phase 2b REZOLVE-AD trial met its primary endpoint of the mean improvement in EASI from baseline at week 16 for all three dose arms of rezpegaldesleukin versus placebo (p<0.001). All three dose arms also achieved statistical significance at week 16 for the key secondary endpoints of EASI-75 (percent of patients who achieve ≥75% reduction in EASI from baseline), EASI-50 (percent of patients who achieve ≥50% reduction in EASI from baseline) and BSA (mean percent improvement in Body Surface Area score from baseline). The q2w arms of rezpegaldesleukin (high and middle doses) achieved statistical significance at week 16 for the key secondary endpoints of vIGA-AD 0/1 (percent of patients achieving a score of 0 or 1 on the validated Investigator’s Global Assessment for Atopic

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Dermatitis with ≥ 2-point reduction from baseline) and Itch NRS (percent of patients with baseline ≥ 4 who experienced a ≥ 4-point reduction in the Itch Numerical Rating Score from baseline). In addition, at week 16, the high dose of 24 μg/kg q2w achieved statistical significance on EASI-90 (percent of patients who achieve ≥ 90% reduction in EASI from baseline). When evaluating EASI-75 and EASI-90 by disease severity using baseline vIGA-AD score, similar responses were observed in severe patients (baseline vIGA-AD of 4) as in moderate patients (baseline vIGA-AD of 3).

In addition, the safety profile for the 16-week induction period for rezpegaldesleukin in the Phase 2b REZOLVE-AD trial was consistent with previously reported results. The most common treatment-emergent adverse events (TEAEs) were local injection site reactions (ISRs), observed in 69.7% of all rezpegaldesleukin-treated patients, with the largest proportion of these being mild or moderate (99.6%). ISRs were self-resolving and <1% of patients discontinued because of an ISR. Across all rezpegaldesleukin doses administered in the study over the 16-week induction period, 55.9% had no reports of ISRs, 30.1% had mild reports, 13.8% had moderate reports, and only 0.2% were severe. Other TEAEs more commonly observed (>5%) in the study treatment arms (n=320) versus placebo (n=73) include eosinophilia (7.8% vs. 2.7%), pyrexia (6.3% vs 2.7%), headache (6.3% vs. 4.1%) and arthralgia (5.0% vs 1.4%). In the pooled rezpegaldesleukin arms, TEAEs, excluding ISRs, were reported in 60.3% of patients and in 57.5% of placebo-treated patients. There was no increased risk of conjunctivitis, oral ulcers, or infections, including oral herpes, in the rezpegaldesleukin arms.

On September 18, 2025, we presented new data from the Phase 2b REZOLVE-AD trial at the European Academy of Dermatology and Venereology (EADV) 2025 Congress. Building on previously presented data, these data demonstrated that high dose rezpegaldesleukin achieved statistical significance on multiple patient-reported outcome assessments at completion of the 16-week induction period. Additionally, as observed interim data for patients who previously received placebo during the induction period and crossed over to receive 24 weeks of treatment with high dose rezpegaldesleukin had increased EASI-75 and vIGA-AD efficacy with extended dosing beyond week 16.

On February 10, 2026, we announced data from the blinded 36-week maintenance period of the Phase 2b REZOLVE-AD trial. Rezpegaldesleukin demonstrated long-term durability and continued atopic dermatitis disease symptom improvement during the maintenance period. Q4w and q12w dosing regimens resulted in sustained disease control for EASI-75, EASI-90, vIGA-AD response, and Itch NRS response, with the 24 μg/kg q4w and q12w regimens showing the highest maintenance of response at week 52.71% and 83% of patients maintained EASI-75 responses and 85% and 63% maintained vIGA-AD 0/1 responses with 24 μg/kgqw4 and q12w dosing, respectively, at week 52. A meaningful proportion of patients achieved new EASI-75, EASI-90, Itch NRS and vIGA-AD 0/1 responses at week 52 of the study. A two to five fold increase in percentage of patients who achieved EASI-100 was observed in the 24 μg/kg q4w and q12w dosing regimens. Among all re-randomized patients from week 16 to week 52, q4w maintenance dosing increased EASI-100 response from 4% to 22% and q12w dosing increased EASI-100 response from 9% to 18%. Among re-randomized patients who had an EASI-75 or vIGA-AD response at maintenance baseline, q4w dosing increased EASI-100 response from 6% to 30% and q12w dosing increased EASI-100 response from 14% to 27%.

The safety profile of rezpegaldesleukin in maintenance was consistent with observations from the induction part of the study. Rezpegaldesleukin was well-tolerated with no new safety concerns identified during the maintenance and escape periods. The discontinuation rate due to adverse events was 3.5% for all aggregated patients. Overall rates of TEAEs were 72% for rezpegaldesleukin treated patients, 65% for placebo patients in maintenance, and 83% for all escape patients. The most frequent TEAE was injection site reactions, nearly all of which were mild (77%), and which occurred at a lower rate and frequency than observed in the initial induction part of the study (discontinuation rate due to injection site reactions was 0.7%).

On December 16, 2025, we announced topline results from the 36-week induction treatment period of the ongoing Phase 2b REZOLVE-AA study being conducted in 92 patients with severe-to-very-severe alopecia areata. Patients were randomized (3:3:2) to receive one of two rezpegaldesleukin doses (24 μg/kg or 18 μg/kg) or placebo, administered as a subcutaneous injection twice monthly. The primary endpoint was the mean percentage reduction from baseline in the Severity of Alopecia Tool (SALT) score at week 36. Following 36 weeks, patients who demonstrated hair growth but had not yet reached SALT>20 had the option to continue for an additional 16 weeks of treatment through week 52 in a blinded extension period. Primary and secondary endpoints were assessed at the end of the 36-week induction treatment period.

Both rezpegaldesleukin dose arms more than doubled the SALT score reduction treatment effect observed with placebo, with the majority of patients experiencing hair growth at week 16 or later. A mean percent SALT reduction at week 36 of 28.2% for the 24 μg/kg rezpegaldesleukin arm, 30.3% for the 18 μg/kg rezpegaldesleukin arm, and 11.2% for placebo (p=0.186 and p=0.121, respectively) was observed. At all timepoints, the rezpegaldesleukin treatment arms separated from placebo in the study. Both rezpegaldesleukin treatment arms showed a dose dependent clinical treatment effect as compared to placebo on the key secondary endpoints of SALT≤30, SALT≤20 and SALT≤10 and SALT30.

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Four of 92 patients included in the modified intent-to-treat (mITT) analysis were found to have study eligibility violations that should have disqualified them for randomization into the trial. Both rezpegaldesleukin treatment arms met statistical significance on the primary endpoint when excluding the four patients with major study eligibility violations. At week 36, the mean percent SALT reduction was 29.6% for 24 μg/kg, 30.4% for 18 μg/kg, and 5.7% for placebo (p=0.049 and p=0.042, respectively). Importantly, the absolute treatment effect for the rezpegaldesleukin arms was similar with or without the exclusion of eligibility violations. One patient in the placebo arm with an eligibility violation accounted for the 5.5% difference in the performance of the placebo arm.

Consistent with prior studies, a favorable safety and tolerability profile was observed, with nearly all TEAEs mild-to-moderate in severity and self-resolving, even in patients receiving 52 weeks of treatment. The discontinuation rate due to adverse events was 1.4% in the combined rezpegaldesleukin treatment arms. No patients discontinued treatment due to an ISR. The placebo adjusted-ISR rate was consistent with prior studies, with 87.0% of ISRs reported as mild. There was no increased risk of major adverse cardiovascular events, thrombosis, infection, acne or oral herpes for REZPEG-exposed patients, compared to placebo.

We continue to advance our most promising research drug candidates into preclinical development with the objective of advancing these early-stage research programs to human clinical studies over the next several years. Our lead research program is based on tumor necrosis factor (TNF) receptor type II (TNFR2) agonism, without modulation of the TNFR1 signaling, after we exercised an option in December 2023 to gain an exclusive license to specified agonistic antibodies and other materials that were developed pursuant to a research collaboration and license option agreement we entered into with Biolojic Design, Ltd. in 2021. TNFR2 signaling drives immunoregulatory function and can provide a direct protective effect for tissue cells. TNFR2 is highly expressed on Tregs, neuronal cells and endothelial cells and has been shown to potentiate the suppressive effects and overall functional properties of Tregs. NKTR-0165 is being developed for potential treatment of autoimmune diseases, such as ulcerative colitis, multiple sclerosis and vitiligo. We are currently conducting Investigational New Drug (IND) enabling studies for this program. We have also designed a unique bispecific antibody, NKTR-0166, that incorporates the TNFR2 agonist epitope and an antagonist epitope validated in the treatment of rheumatology diseases. As a dual agonist:antagonist of known pathways associated with key pathways linked to disease pathogenesis, this investigational antibody is being developed to address a number of rheumatic disorders.

In oncology, we focus on developing medicines that target biological pathways that stimulate and sustain the body’s immune response in order to fight cancer. Our drug candidate NKTR-255 is an investigational biologic that is designed to target the IL-15 pathway in order to activate the body’s innate and adaptive immunity. Through optimal engagement of the IL-15 receptor complex, NKTR-255 is designed to enhance functional NK cell populations and formation of long-term immunological memory, which may lead to sustained and durable anti-tumor immune response.

We are continuing select developmental studies of NKTR-255 in combination with cell therapies and checkpoint inhibitors while we evaluate additional strategic partnership pathways for the program. We are continuing our oncology clinical collaboration with Merck KGaA to evaluate the maintenance regimen of NKTR-255 in combination with avelumab, a PD-L1 inhibitor, in patients with locally advanced or metastatic urothelial carcinoma in the Phase II JAVELIN Bladder Medley study. We also have two investigator sponsored studies, one evaluating NKTR-255 following Breyanzi® CD19 CAR-T cell therapy in patients with relapsed/refractory large B-cell lymphoma and one evaluating NKTR-255 in combination with IMFINZI (durvalumab) in patients with unresectable Stage 3 NSCLC who have received chemoradiation.

We have historically derived substantially all of our revenue and significant amounts of research and development operating capital from our collaboration agreements. We have received upfront and milestone payments and cost-sharing reimbursements under a number of previous collaboration agreements, and certain of our collaboration partners have borne substantial costs of developing our drug candidates. We expect we will continue our approach of entering into revenue-generating collaboration agreements to pay in whole or in part the development costs of our drug candidates.

Several of our historical collaboration agreements have resulted in approved drugs, for which we may be entitled to royalties for net sales of these approved drugs. However, we have sold our rights to receive royalties under these arrangements, including:

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2012 Purchase and Sale Agreement: In 2012, we sold all of our rights to receive royalties from CIMZIA® (for the treatment of Crohn’s disease and other autoimmune indications) and MIRCERA® (for the treatment of anemia associated with chronic kidney disease) under our collaborations with UCB Pharma (UCB) and F. Hoffmann-La Roche Ltd, respectively, to RPI Finance Trust (RPI), an affiliate of Royalty Pharma for $124.0 million.

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2020 Purchase and Sale Agreement: In December 2020, we sold our rights, subject to a cap, to receive royalties from MOVANTIK® / MOVENTIG® (for the treatment of opioid-induced constipation), ADYNOVATE® / ADYNOVI® (a half-life extension product of Factor VIII) and other hemophilia products,

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under our arrangements with AstraZeneca AB, Baxalta, Inc. (a wholly owned-subsidiary of Takeda Pharmaceutical Company Ltd.), and Novo Nordisk A/S, respectively, for $150.0 million to entities managed by Healthcare Royalty Management, LLC (HCR). On March 4, 2024, Nektar and HCR amended the 2020 Purchase and Sale Agreement to remove the cap on the royalties in exchange for $15.0 million. See Note 6 to our Consolidated Financial Statements for additional information.

We continued to manufacture the polymer reagents used in the production of some of the drug products until the sale of our manufacturing facility in Huntsville, Alabama (the Facility) in December 2024. On December 2, 2024, we completed the sale of the Facility and assigned our manufacturing and supply agreements to Gannet BioChem, an affiliate of Ampersand Management LLC d/b/a Ampersand Capital Partners (Ampersand) for consideration of $64.7 million in cash, net of transaction costs, and an approximate 20% equity interest at the time of close in Gannet BioChem. See Note 11 to our Consolidated Financial Statements for additional information. The sale of the Facility does not alter the royalties or other milestones payable under these agreements or our collaboration agreement with UCB for dapirolizumab pegol as further disclosed in Note 9 to our Consolidated Financial Statements.

Our business is subject to significant risks, including the risks inherent in our development efforts, the results of our clinical trials, our dependence on the marketing efforts by our collaboration partners, uncertainties associated with obtaining and enforcing patents, the lengthy and expensive regulatory approval process and competition from other products. Drug research and development is an inherently uncertain process with a high risk of failure at every stage prior to approval. The timing and outcome of clinical trial results are extremely difficult to predict. Clinical development successes and failures can have a disproportionately positive or negative impact on our scientific and medical prospects, financial condition and prospects, results of operations and market opportunities. For a discussion of these and some of the other key risks and uncertainties affecting our business, see Item 1A “Risk Factors.”

With respect to financing our near-term business needs, as set forth below in “Key Developments and Trends in Liquidity and Capital Resources,” we estimate we have working capital to fund our current business plans through at least the next twelve months. At December 31, 2025, we had approximately $245.8 million in cash and investments in marketable securities.

On July 2, 2025, we completed the sale and issuance of 4,893,618 shares of our common stock in an underwritten public offering (the 2025 Offering) at a price of $23.50 per share. The net proceeds to the Company from the 2025 Offering totaled approximately $107.2 million, after deducting underwriting discounts, commissions and offering costs.

We previously entered into an equity distribution agreement (the April 2025 ATM Sales Agreement) with Piper Sandler & Co. and BTIG, LLC to sell shares of our common stock by any method permitted that is deemed to be an “at-the-market” equity offering as defined in Rule 415(a)(4) promulgated under the Securities Act. In September and October 2025, we issued 1,273,923 shares of our common stock under the April 2025 ATM Sales Agreement at a weighted average price of $58.87 per share for net proceeds of $72.5 million after deducting related commissions and offering costs. No April 2025 ATM shares remain available for issuance under the April 2025 ATM Sales Agreement.

On February 13, 2026, we completed the sale of and issuance of 7,637,931 shares of common stock at a price of $58.00 per share and 293,103 pre-funded warrants at price of $57.9999 per pre-funded warrant in an underwritten public offering (the 2026 Offering). The estimated net proceeds from the 2026 Offering totaled approximately $432.0 million, after deducting underwriting discounts and commissions and estimated offering expenses.

From February 20, 2026 through March 11, 2026, we issued 639,131 shares of our common stock under the November 2025 ATM Sales Agreement at a weighted average price of $71.15 per share for net proceeds of $44.1 million after deducting related commissions of approximately $1.4 million.

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Results of Operations

The results of operations for the years ended December 31, 2025 and 2024 are presented below (in thousands, except percentages).

Revenue:

License, collaboration and other revenue 300 597 (297 ) (50 )%

Operating costs and expenses:

Gain on sale of the Huntsville manufacturing facility — (40,390 ) 40,390 (100 )%

Non-operating income (expense):

Loss from equity method investment (8,727 ) — (8,727 ) n/m

n/m - not meaningful

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Revenue

Our revenue has historically been derived from our collaboration agreements, under which we may receive product sales revenue, royalties, and license fees, as well as development and sales milestones and other contingent payments. We recognize revenue when we transfer promised goods or services to our collaboration partners.

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Product sales and Cost of goods sold: Product sales included predominantly fixed price manufacturing and supply agreements with our collaboration partners and were the result of firm purchase orders from those partners. Due to the sale of the Facility in December 2024, we no longer recognize product sales or costs of goods sold under these arrangements in 2025.

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Non-cash royalty revenue and Non-cash interest expense: We recognize non-cash royalty revenue and non-cash interest expense resulting from royalties on several products for which we had previously sold our rights to receive royalties under the 2012 and 2020 Purchase and Sale Agreements. See Note 6 to our Consolidated Financial Statements for additional information regarding these agreements. These non-cash revenues and expenses have no effect on our cash flows, and we do not consider them material to our operations. We expect non-cash royalty revenue to decrease for 2026 as compared to 2025 due to the end of the royalty terms for several products, and we expect non-cash interest expense to increase slightly as a result of a higher effective interest rate.

On March 4, 2024, Nektar and HCR amended the 2020 Purchase and Sale Agreement to remove the cap on the royalties in exchange for a $15.0 million payment to Nektar. See Note 6 to our Consolidated Financial Statements for additional information.

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License, collaboration and other revenue: License, collaboration and other revenue includes the recognition of upfront payments, milestone and other contingent payments received in connection with our license and collaboration agreements. The amount of revenue depends in part upon the estimated recognition period of the upfront payments allocated to continuing performance obligations, the achievement of milestones and other contingent events, the continuation of existing collaborations, the amount of research and development work, and entering into new collaboration agreements, if any. License, collaboration and other revenue was not material for 2024 or 2025, and, unless we enter into a new collaboration agreement with upfront payments, we do not expect to recognize significant revenue in 2026.

The timing and future success of our drug development programs and those of our collaboration partners are subject to a number of risks and uncertainties. See Item 1A. Risk Factors for discussion of the risks associated with the complex nature of our collaboration agreements.

Research and Development Expense

Research and development expense consists primarily of clinical study costs, contract manufacturing costs, direct costs of outside research, materials, supplies, licenses and fees as well as personnel costs (including salaries, benefits, and non-cash stock-based compensation). Research and development expense also includes certain overhead allocations of support costs.

The following table presents expenses incurred for direct third-party costs, including clinical and regulatory services, contract manufacturing, clinical supplies, and preclinical study support for each of our drug candidates. The table also presents personnel, overhead and other indirect costs as we utilize our employee and infrastructure resources across multiple development and research programs (in thousands):

Clinical Study Year Ended December 31,

Discovery research and other programs Various 1,833 2,334

Stock-based compensation and depreciation 5,707 9,429

(1)

Clinical Study Status as of December 31, 2025. Definitions are provided in Part I, Item 1. Business.

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Research and development expense for rezpegaldesleukin for both periods includes the costs of our Phase 2b RESOLVE-AD and RESOLVE-AA trials. These expenses increased for the full year 2025 as compared to the full year 2024, as we commenced certain activities to support a Phase 3 program in atopic dermatitis in 2025. We expect the costs of development of rezpegaldesleukin for full year 2026 to significantly increase as we initiate a Phase 3 program in atopic dermatitis.

Research and development expense for NKTR-0165 was consistent for the periods presented, as we are conducting IND enabling activities for this program. We expect the costs of development of NKTR-0165 to decrease for full year 2026 as compared to 2025 as we have completed most of our IND enabling activities. We may owe additional milestone payments to Biolojic Design, Ltd., as further disclosed in Note 9 to our Consolidated Financial Statements.

Research and development expense for NKTR-255 decreased for the full year 2025 as compared to the full year 2024, as we have completed our Phase 2 study to evaluate NKTR-255 following Yescarta® or Breyanzi® CD19 CAR-T cell therapy in patients with large B-cell lymphoma. Our development expense for NKTR-255 for the periods presented include our oncology clinical collaboration with Merck KGaA to evaluate the maintenance regimen of NKTR-255 in combination with avelumab, a PD-L1 inhibitor, in patients with locally advanced or metastatic urothelial carcinoma in the Phase II JAVELIN Bladder Medley study, and investigator-sponsored studies, one evaluating NKTR-255 following Breyanzi® CD19 CAR-T cell therapy in patients with relapsed/refractory large B-cell lymphoma and one evaluating NKTR-255 in combination with IMFINZI (durvalumab) in patients with unresectable Stage 3 NSCLC who have received chemoradiation. We expect the costs of development of NKTR-255 to decrease for full year 2026 as compared to full year 2025 as we complete the investigator-sponsored studies.

Personnel, overhead and other costs increased for the full year 2025 as compared to the full year 2024, for increased personnel costs to support our rezpegaldesleukin program and increases in allocations of overhead costs to research and development expense as we no longer allocate such costs to costs of goods sold following the sale of the Facility. Stock-based compensation expense decreased for the periods presented due to lower valuations on more recent grants as a result of a decrease in our stock price. We expect personnel, overhead and other costs for full year 2026 to increase compared to full year 2025 to support our Phase 3 rezpegaldesleukin program in atopic dermatitis.

We expect total research and development expense to increase significantly for full year 2026 compared to 2025 to support our Phase 3 rezpegaldesleukin program in atopic dermatitis.

The timing and amount of our future clinical trial expenses will vary significantly based upon our evaluation of ongoing clinical results and the structure, timing, and scope of additional clinical development programs and potential clinical collaboration partnerships (if any) for these programs.

In addition to our drug candidates that we plan to evaluate in clinical development during 2026 and beyond, we believe it is vitally important to continue our investment in a pipeline of new drug candidates to continue to build the value of our drug candidate pipeline and our business. We continue our interest in identifying new drug candidates across a wide range of molecule classes, including small molecules and large proteins, peptides and antibodies, across multiple therapeutic areas. We also plan from time to time to evaluate opportunities to in-license potential drug candidates from third parties to add to our drug discovery and development pipeline. We plan to continue to advance our most promising early research drug candidates into preclinical development with the objective to advance these early-stage research programs to human clinical studies over the next several years.

Our expenditures on current and future preclinical and clinical development programs are subject to numerous uncertainties in timing and cost to completion. In order to advance our drug candidates through clinical development, each drug candidate must be tested in numerous preclinical safety, toxicology and efficacy studies. We then conduct clinical studies for our drug candidates that take several years to complete. The cost and time required to complete clinical trials may vary significantly over the life of a clinical development program as a result of a variety of factors, including but not limited to:

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the number of patients required for a given clinical study design;

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the length of time required to enroll clinical study participants;

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the number and location of sites included in the clinical studies;

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the clinical study designs required by the health authorities (i.e. primary and secondary endpoints as well as the size of the study population needed to demonstrate efficacy and safety outcomes);

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the potential for changing standards of care for the target patient population;

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the competition for patient recruitment from competitive drug candidates being studied in the same clinical setting;

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the costs of producing supplies of the drug candidates needed for clinical trials and regulatory submissions;

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the safety and efficacy profile of the drug candidate;

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the use of clinical research organizations to assist with the management of the trials; and

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the costs and timing of, and the ability to secure, approvals from government health authorities.

Furthermore, our strategy includes the potential of entering into collaborations with third parties to participate in the development and commercialization of some of our drug candidates, or clinical collaborations where we would share costs and operational responsibility with a partner. In certain situations, the clinical development program and process for a drug candidate and the estimated completion date will largely be under the control of that third party and not under our control. We cannot forecast with any degree of certainty which of our drug candidates will be subject to future collaborations or how such arrangements would affect our development plans or capital requirements.

General and Administrative Expense

General and administrative expense includes the cost of administrative staffing, finance and legal activities, including certain overhead support allocations. Additionally, general and administrative expense includes our lease and other facilities expenses, net of sublease income.

General and administrative expense decreased for the full year 2025 as compared to the full year 2024 due to decreases in facilities expense and stock-based compensation expense. Facilities expense decreased primarily due to the impairment charges we recorded in 2024, resulting in decreased lease expense following the impairment, and stock-based compensation expense decreased due to lower valuations on more recent grants due to the decrease in our stock price.

We expect general and administrative expense for full year 2026 to decrease slightly as compared to 2025.

Restructuring and Impairment

As discussed in Note 10 to our Consolidated Financial Statements, we have incurred significant costs as a result of our 2022 and 2023 Restructuring Plans. In connection with these events, we reported the following costs in restructuring and impairment as further described and disclosed in Note 10 to our Consolidated Financial Statements (in thousands):

Year ended December 31,

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Impairment of right-of-use assets and property and equipment: The non-cash impairment charges for the full year 2024 relate to our leased spaces in San Francisco, CA, including our office and laboratory space on Mission Bay Blvd. South (the Mission Bay Facility) and our office space on Third St. (the Third St. Facility), reflecting deteriorations in both the laboratory and office lease markets. The non-cash impairment charges for the full year 2025 reflect additional impairment charges for the Mission Bay Facility as these lease markets continue to demonstrate a degree of weakness.

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Contract termination and other restructuring charges: We recognized $4.9 million and $7.3 million in contract termination costs for the full years 2025 and 2024, respectively, in connection with our Restructuring Plans. Because we continue to adjust the liability based on updates to our assumptions at each reporting date, we will continue to recognize expense as our estimates change until final settlement.

Gain on Sale of the Huntsville Manufacturing Facility

As discussed in Note 1 to our Consolidated Financial Statements, on December 2, 2024, we sold the Facility which included the assignment of our manufacturing and supply agreements to Gannet BioChem, an affiliate of Ampersand Capital Partners, for consideration of $64.7 million in cash, net of transaction costs, and an approximate 20% equity interest at the

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time of close in Gannet BioChem. This resulted in a net gain on sale of $40.4 million in 2024, after accounting for the net carrying value of all assets and liabilities sold and closing costs. See Note 11 to our Consolidated Financial Statements for additional information.

Interest Income

Interest income decreased for the full year 2025 as compared to the full year 2024, primarily due to lower investment balances as we have utilized our cash to fund our operations. We expect interest income to increase for 2026 due to the approximate $432.0 million in net proceeds from the 2026 Offering and $44.1 million in ATM proceeds through March 11, 2026 under the November 2025 ATM Sales Agreement.

Loss from Equity Method Investment

As discussed in Note 4 to our Condensed Consolidated Financial Statements, we determine our gain or loss on our equity method investment in Gannet BioChem using the hypothetical liquidation at book value (HLBV) due to Ampersand’s priority liquidation preference and right to receive a cumulative preferred dividend. The HLBV method is a balance sheet approach that calculates the change in the hypothetical amount we and Ampersand would be entitled to receive if Gannet BioChem were liquidated at book value at the end of each period, subject to certain adjustments for any contributions, distributions and basis differences. We report our gain or loss from our equity method investment in Gannet BioChem on a three-month lag. Therefore, our loss recorded for the for the full year 2025, reflects Gannet BioChem’s activities from closing on December 2, 2024 through September 30, 2025. Our losses for these periods reflect Ampersand’s cumulative preferred dividend earned for such periods and Gannet BioChem’s net losses for such periods. Our loss of $8.7 million for the full year 2025 includes $2.5 million of Ampersand’s transaction costs deducted from Ampersand’s cash investment in Gannet BioChem.

We do not expect a significant gain or loss from equity method investment in 2026.

Liquidity and Capital Resources

We have financed our operations primarily through revenue from upfront and milestone payments under our strategic collaboration agreements, royalties and product sales, as well as public and private placements of debt and equity securities. As of December 31, 2025, we had approximately $245.8 million in cash and investments in marketable securities.

During 2024, we entered into the following transactions:

•

On February 12, 2024, for total cash consideration paid of $3.0 million, we repurchased the 552,307 shares previously sold to Bristol Myers Squibb Company (BMS). See Note 9 to our Consolidated Financial Statements for additional information.

•

On March 4, 2024, we entered into a Securities Purchase Agreement with TCG Crossover Fund II, L.P. (TCG), pursuant to which we issued a pre-funded warrant (the TCG Pre-funded Warrant) to TCG to purchase 1,666,667 shares of Nektar’s common stock for gross proceeds of $30.0 million (or a purchase price of $18.00 per share of common stock that can be issued upon exercise of the TCG Pre-funded Warrant). On May 28, 2024, we filed with the SEC a registration statement on Form S-3 (file no. 333-279760) registering for the resale of up to 1,666,667 shares of Nektar’s common stock upon exercise of the TCG Pre-funded Warrant pursuant to the Securities Purchase Agreement. The registration statement became effective on June 5, 2024. In July 2025, TCG exercised the warrant in full. See Note 8 to our Consolidated Financial Statements for additional information.

•

On March 4, 2024, for total cash consideration received of $15.0 million, Nektar entered into an amendment with HCR to remove the cap under the 2020 Purchase and Sale Agreement. See Note 6 to our Consolidated Financial Statements for additional information.

•

On December 2, 2024, we completed the sale of the Facility which included the assignment of our manufacturing and supply agreements to Gannet BioChem, an affiliate of Ampersand Capital Partners, for consideration of $64.7 million in cash, net of transaction costs,and an approximate 20% equity interest at the time of close in Gannet BioChem. See Note 11 to our Consolidated Financial Statements for additional information.

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and or units having an aggregate public offering price of up to $300.0 million. In connection with the filing of the April 2025 Shelf Registration Statement, we also entered into an equity distribution agreement (the April 2025 ATM Sales Agreement) with Piper Sandler & Co. and BTIG, LLC, relating to the sale of our common stock having an aggregate offering price of up to $75.0 million (the April 2025 ATM Shares). The sales of the ATM shares could be made by any method permitted that is deemed to be an “at-the-market” equity offering as defined in Rule 415(a)(4) promulgated under the Securities Act, including sales made directly on or through Nasdaq or on any other existing trading market for our common stock. We have agreed to pay Piper Sandler & Co. and BTIG, LLC a commission equal to 3.0% of the gross sales price of all common stock sold through them as sales agents.

On July 2, 2025, pursuant to the April 2025 Shelf Registration Statement, we completed the sale and issuance of 4,893,618 shares of our common stock in an underwritten public offering (the 2025 Offering) at a price of $23.50 per share. The net proceeds to the Company from the 2025 Offering totaled approximately $107.2 million, after deducting underwriting discounts, commissions and offering costs. See Note 8 to our Consolidated Financial Statements for additional information.

In September and October 2025, we issued 1,273,923 shares of our common stock under the April 2025 ATM Sales Agreement at a weighted average price of $58.87 per share for net proceeds of $72.5 million after deducting related commissions and offering costs of approximately $2.5 million. No April 2025 ATM shares remain available for issuance under the April 2025 ATM Sales Agreement.

On November 12, 2025, we filed a new registration statement on Form S-3ASR and related prospectus (the November 2025 Shelf Registration), as a “well-known seasoned issuer,” as defined in Rule 405 under the Securities Act. The November 2025 Shelf Registration became automatically effective upon filing, and permits us to offer, from time to time, an unspecified amount of common stock, preferred stock, debt securities and warrants.

On November 12, 2025, we also entered into a new equity distribution agreement (the November 2025 ATM Sales Agreement) with Piper Sandler & Co. and BTIG, LLC, relating to the sale of our common stock having an aggregate offering price of up to $110.0 million in an “at-the-market” offering (the November 2025 ATM Shares) under the April 2025 Shelf Registration Statement. As of December 31, 2025, no shares were issued under the November 2025 ATM Sales Agreement. From February 20, 2026 through March 11, 2026, we issued 639,131 shares of our common stock under the November 2025 ATM Sales Agreement at a weighted average price of $71.15 per share for net proceeds of $44.1 million.

We estimate that we have working capital to fund our current business plans for at least the next twelve months from the date of filing.

We expect the clinical development of our drug candidates, including rezpegaldesleukin, NKTR-255, NKTR-0165, and NKTR-0166 will continue to require significant investment to continue to advance in clinical development with the objective of obtaining regulatory approval or entering into one or more collaboration partnerships. In the past, we have received a number of significant payments from collaboration agreements and other significant transactions, including $1.9 billion in total consideration received under our arrangement with BMS, development cost reimbursements from BMS, and a $150.0 million upfront payment from Eli Lilly and Company for our collaboration agreement for rezpegaldesleukin. Additionally, certain of our collaboration partners have borne substantial costs of developing our drug candidates. We expect we will continue our approach of entering into revenue-generating collaboration agreements to pay in whole or in part the development costs of our drug candidates.

Our current business is subject to significant uncertainties and risks as a result of, among other factors, clinical and regulatory outcomes for rezpegaldesleukin, NKTR-0165, NKTR-0166 and NKTR-255; the sales levels for those products, if and when they are approved; whether, when and on what terms we are able to enter into new collaboration transactions; expenses being higher than anticipated, unplanned expenses and the need to satisfy contingent liabilities, including litigation matters and indemnification obligations; and cash receipts, including sublease income, being lower than anticipated.

We have no credit facility or any other sources of committed capital. The availability and terms of various financing alternatives, if required in the future, substantially depend on many factors including the success or failure of drug development programs in our pipeline. The availability and terms of financing alternatives and any future significant payments from existing or new collaborations depend on the positive outcome of ongoing or planned clinical studies, whether we or our partners are successful in obtaining regulatory authority approvals in major markets, and if approved, the

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commercial success of these drugs, as well as general capital market conditions. We may pursue various financing alternatives to fund the expansion of our business as appropriate.

As a result of our restructuring plans, we are seeking to sublease all of our laboratory and office space in the Mission Bay Facility and our office space in the Third St. Facility, and we have current subleases for a portion of the Mission Bay Facility. The San Francisco Bay Area office lease market has been negatively impacted by economic uncertainties, particularly impacting the technology industry, and the change in work habits, as employees continue to work remotely. Accordingly, for the Third St. Facility, there is significant uncertainty as to whether or when we will be able to enter into a sublease as well as the economic terms of such subleases, if any. Meanwhile, the San Francisco Bay Area life sciences lease market continues to be weak as a significant amount of leasable space remains available in the San Francisco Bay Area. Accordingly, there is uncertainty as to whether or when we will be able to enter into a sublease as well as the economic terms of such subleases, if any.

Due to the potential for adverse developments in the credit markets, we may experience reduced liquidity with respect to some of our investments in marketable securities. These investments are generally held to maturity, which, in accordance with our investment policy, is less than two years. However, if the need arises to liquidate such securities before maturity, we may experience losses on liquidation. To date we have not experienced any liquidity issues with respect to these securities. We believe that, even allowing for potential liquidity issues with respect to these securities and the effect of various conditions on the financial markets, our remaining cash and investments in marketable securities will be sufficient to meet our anticipated cash needs for at least the next twelve months.

Cash flows from operating activities

Cash flows used in operating activities for the years ended December 31, 2025 and 2024 totaled $208.5 million and $175.7 million, respectively.

We expect that cash flows used in operating activities, excluding upfront, milestone and other contingent payments received, if any, will increase significantly for 2026 as compared to 2025 to support our Phase 3 rezpegaldesleukin program in atopic dermatitis.

Cash flows from investing activities

For the year ended December 31, 2025, our purchases of investments net of maturities were immaterial as the proceeds from our equity financings substantially offset funding our operations. For the year ended December 31, 2024 the maturities of our investments, net of purchases, totaled $78.7 million, which we used to fund our operations.

As discussed above, in December 2024, we completed the sale of the Facility which included the assignment of our manufacturing and supply agreements to Gannet BioChem, an affiliate of Ampersand Capital Partners, for consideration of $64.7 million in cash, net of transaction costs, and an approximate 20% equity interest at the time of close in Gannet BioChem.

Our other investing activities were not significant for the periods presented.

Cash flows from financing activities

Other than the financing activities described above, our cash flows from financing activities for the years ended December 31, 2025 and 2024 were not significant.

Critical Accounting Policies and Estimates

The preparation and presentation of financial statements in conformity with U.S. generally accepted accounting principles (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period.

We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances, the results of which form our basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. We evaluate our estimates on an ongoing basis. Actual results may differ from those estimates under different assumptions or conditions.

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Impairment of Long-Lived Assets

We assess the impairment of long-lived assets whenever events or changes in business circumstances indicate that the carrying amounts of the assets may not be fully recoverable. In the case of property and equipment and right-of-use assets for our leases, we determine whether there has been an impairment by comparing the carrying value of the asset to the anticipated net cash flows associated with the asset. If such cash flows are less than the carrying value, we write down the asset to its fair value, which may be measured as anticipated discounted net cash flows associated with the asset, discounted at a rate that we believe a market participant would utilize to reflect the risks associated with the cash flows, such as credit risk.

As discussed in Note 10, in connection with our 2022 and 2023 Restructuring Plans, we decided to seek a sublease for all of our leased spaces in the Third St. Facility and the Mission Bay Facility. Accordingly, we evaluate each space for impairment at each reporting date, as facts and circumstances change. The significant assumptions in our impairment analysis relate to sublease income, including the length of time to enter into a sublease, sublease rental payments, free rent periods, tenant improvement allowances and broker commissions. When available, we use sublease negotiations or agreements, but in the absence of such information, we develop our own subjective estimates based on current real estate trends and market conditions. Accordingly, our estimates are subject to significant risk, and the terms of sublease agreements, if any, and the resulting amount and timing of sublease income, if ever realized, may be materially different than our estimates.

As part of our evaluation of each sublease space, we separately compare the estimated undiscounted sublease income, if any, as described above, for each sublease to the net book value of the related long-term assets, which include right-of-use assets and certain property, plant and equipment, primarily for leasehold improvements (collectively, sublease assets). If such sublease income exceeds the net book value of the sublease assets, we do not record an impairment charge. Otherwise, we record an impairment charge by reducing the net book value of the sublease assets to their estimated fair value, which we determined by discounting the estimated sublease income using the estimated borrowing rate of a market participant subtenant. Determination of these key assumptions is complex and highly judgmental.

For certain impairment charges, we used the terms of active sublease negotiations or agreements to estimate sublease income. However, for the most significant impairment charges we recorded, we developed our estimates based on current real estate trends and market conditions. Given the current office and life sciences lease market rental conditions in San Francisco, our estimates are subject to significant uncertainty. The ultimate amount of sublease income may differ significantly than the amounts used to record our impairment charges.

Collaborative Arrangements

When we enter into collaboration agreements with pharmaceutical and biotechnology partners, we assess whether the arrangements fall within the scope of Accounting Standards Codification (ASC) 808, Collaborative Arrangements (ASC 808) based on whether the arrangements involve joint operating activities and whether both parties have active participation in thearrangement and are exposed to significant risks and rewards. To the extent that the arrangement falls within the scope of ASC 808, we assess whether the payments between us and our collaboration partner fall within the scope of other accounting literature. If we conclude that payments from the collaboration partner to us represent consideration from a customer, such as license fees and contract research and development activities, we account for those payments within the scope of ASC 606, Revenue from Contracts with Customers. However, if we conclude that our collaboration partner is not a customer for certain activities and associated payments, such as for certain collaborative research, development, manufacturing and commercial activities, we record such payments as a reduction of research and development expense or general and administrative expense, based on where we record the underlying expense.

Revenue Recognition

We recognize license, collaboration and other research revenue, including the upfront fees and milestone payments based on the facts and circumstances of each contractual agreement. At the inception of each agreement, we determine which promises represent distinct performance obligations, for which management must use significant judgment. Additionally, at inception and at each reporting date thereafter, we must determine and update, as appropriate, the transaction price, which includes variable consideration such as development and commercial launch milestones. We must use judgment to determine when to include the variable consideration for these milestones in the transaction price such that inclusion of such variable consideration will not result in a significant reversal of revenue recognized when the contingency surrounding the variable consideration is resolved. Due to the significant uncertainties involved with clinical development and regulatory approval, we generally do not believe that we would update the transaction price before events that are outside of our control occur, such as the release of clinical trial results, regulatory acceptance of a BLA or similar filing or regulatory approval. However, if these results are positive, we may conclude that certain milestones meet the recognition requirements for inclusion in the transaction price and therefore we would recognize them as revenue before the milestone event occurs and the payment becomes due to us, provided that the achievement of the milestone is within our control.

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Accrued Clinical Trial Expenses

We record an accrued expense for the estimated unbilled costs of our clinical study activities performed by third parties, and there may be significant delays between these expenses being incurred and the timing of vendor submission of invoices to us. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows to our vendors. Payments under the contracts depend on factors such as the achievement of certain events, successful enrollment of patients and completion of certain clinical trial activities. We generally recognize costs associated with the start-up and reporting phases of the clinical trials as incurred. We generally accrue costs associated with the treatment phase of clinical trials based on the estimated activities performed by our third-party vendors, including our contract research organizations. In specific circumstances, such as for certain time-based costs, we recognize clinical trial expenses ratably over the service period, as we believe that this methodology may be more reflective of the timing of costs incurred.

We base our estimates on the best information available at the time. However, additional information may become available to us, which may allow us to make a more accurate estimate in future periods. In this event, we may be required to record adjustments to research and development expenses in future periods when the actual level of activity becomes more certain. Such increases or decreases in cost are generally considered to be changes in estimates and will be reflected in research and development expenses in the period identified.

Recent Accounting Pronouncements

For information about recent accounting pronouncements, see Note 1 to our Consolidated Financial Statements.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Inflation Risk

We are exposed to the risk of inflation, which increased significantly during 2023 and continued to increase in 2025, and may result in increases to our operating expenses.

Interest Rate and Market Risk

The primary objective of our investment activities is to preserve principal while at the same time maximizing yields without significantly increasing risk. To achieve this objective, we invest in liquid, high quality debt securities. Our investments in debt securities are subject to interest rate risk. To minimize the exposure due to an adverse shift in interest rates, we invest in securities with maturities of two years or less and maintain a weighted average maturity of one year or less.

A hypothetical 50 basis point increase in interest rates would result in an approximate $0.3 million decrease, less than 1%, in the fair value of our available-for-sale securities at December 31, 2025. This potential change is based on sensitivity analyses performed on our investment securities at December 31, 2025. Actual results may differ materially. The same hypothetical 50 basis point increase in interest rates would have resulted in an approximate $0.5 million decrease, less than 1%, in the fair value of our available-for-sale securities at December 31, 2024.

As of December 31, 2025, we held $216.5 million of available-for-sale investments, excluding money market funds, with an average time to maturity of four months. To date we have not experienced any liquidity issues with respect to these securities, but should such issues arise, we may be required to hold some, or all, of these securities until maturity. We believe that, even allowing for potential liquidity issues with respect to these securities, our remaining cash, cash equivalents, and investments in marketable securities will be sufficient to meet our anticipated cash needs for at least the next twelve months. Based on our available cash, the timing of the maturities of our investments and our expected operating cash requirements, we currently do not intend to sell these securities prior to maturity and it is more likely than not that we will not be required to sell these securities before we recover the amortized cost basis.

Foreign Currency Risk

As a result of the sale of our research and development facility in India, we have cash and investment balances in India that we intend to repatriate as part of our closure of this entity. We are subject to foreign currency exchange risk until we repatriate these funds.

The majority of our revenue, expense, and capital purchasing activities are transacted in U.S. dollars. However, we have contracts with contract manufacturing organizations in Europe and incur costs from sites in a variety of international

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locations which are paid in their respective local currencies. Accordingly, we are subject to foreign currency exchange risk for these transactions.

Our international operations are subject to risks typical of international operations, including, but not limited to, differing economic conditions, changes in political climate, differing tax structures, other regulations and restrictions, and foreign exchange rate volatility. We do not utilize derivative financial instruments to manage our exchange rate risks. We do not believe that inflation has had a material adverse impact on our revenues or operations in any of the past two years.

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Item 8. Financial Statements and Supplementary Data

NEKTAR THERAPEUTICS

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Page

Report of Independent Registered Public Accounting Firm (PCAOB ID: 42) 64

Notes to Consolidated Financial Statements 71

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Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Nektar Therapeutics

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Nektar Therapeutics (the Company) as of December 31, 2025 and 2024, the related consolidated statements of operations, comprehensive loss, stockholders’ equity and cash flows for each of the two years in the period ended December 31, 2025, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the two years in the period ended December 31, 2025, in conformity with U.S. generally accepted accounting principles.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of the critical audit matter does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the account or disclosure to which it relates.

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Accrued clinical trial expenses

/s/ Ernst & Young LLP

We have served as the Company’s auditor since 1993.

San Mateo, California

March 12, 2026

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NEKTAR THERAPEUTICS

CONSOLIDATED BALANCE SHEETS

(In thousands, except share and per share data)

December 31,

ASSETS

Current assets:

Long-term investments — 13,869

Property, plant and equipment, net 2,060 3,411

Operating lease right-of-use assets 2,941 8,413

Equity method investment in Gannet BioChem 3,491 12,218

LIABILITIES AND STOCKHOLDERS’ EQUITY

Current liabilities:

Operating lease liabilities, current portion 20,495 19,868

Operating lease liabilities, less current portion 65,256 82,696

Liabilities related to the sales of future royalties, net 63,157 91,776

Commitments and contingencies

Stockholders’ equity:

Accumulated other comprehensive income (loss) 17 61

Total liabilities and stockholders’ equity $ 280,406 $ 303,850

(1)All share and per share amounts have been retrospectively adjusted to reflect a one-for-fifteen reverse stock split (see Note 8).

The accompanying notes are an integral part of these consolidated financial statements.

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NEKTAR THERAPEUTICS

CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except share and per share data)

Year Ended December 31,

Revenue:

Product sales $ — $ 33,563

Non-cash royalty revenue related to the sales of future royalties 54,932 64,267

License, collaboration and other revenue 300 597

Operating costs and expenses:

Cost of goods sold — 30,686

Gain on sale of the Huntsville manufacturing facility — (40,390 )

Non-operating income (expense):

Total non-operating income (expense), net (15,385 ) (14,002 )

Benefit for income taxes (138 ) (239 )

Loss from equity method investment (8,727 ) —

Basic and diluted net loss per share $ (9.73 ) $ (8.68 )

(1)All share and per share amounts have been retrospectively adjusted to reflect a one-for-fifteen reverse stock split (see Note 8).

The accompanying notes are an integral part of these consolidated financial statements.

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NEKTAR THERAPEUTICS

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS

(In thousands, except share and per share data)

Year Ended December 31,

Other comprehensive income (loss):

Net unrealized loss on available-for-sale investments (18 ) (15 )

Net foreign currency translation adjustment (26 ) (4 )

Other comprehensive loss (44 ) (19 )

The accompanying notes are an integral part of these consolidated financial statements.

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NEKTAR THERAPEUTICS

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(In thousands, except share and per share data)

Shares(1) Amount(1) Shares(1) Amount Par Value(1) Income/(Loss) Deficit Equity

Shares issued under equity compensation plans 179,324 — — — 118 — — 118

Issuance of prefunded warrant — — — — 30,000 — — 30,000

Shares issued under equity compensation plans 159,623 — — — 864 — — 864

Shares issued upon exercise of prefunded warrant 1,666,667 — — — 2 — — 2

(1)All share and per share amounts have been retrospectively adjusted to reflect a one-for-fifteen reverse stock split (see Note 8).

The accompanying notes are an integral part of these consolidated financial statements.

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NEKTAR THERAPEUTICS

CONSOLIDATED STATEMENTS OF CASH FLOWS

(In thousands)

Year Ended December 31,

Cash flows from operating activities:

Adjustments to reconcile net loss to net cash used in operating activities:

Loss from equity method investment 8,727 —

Depreciation and amortization 1,026 4,391

Impairment of right-of-use assets and property and equipment 4,441 8,329

Gain on sale of the Huntsville manufacturing facility — (40,390 )

Provision for net realizable value of inventory — 949

Amortization of premiums (discounts), net (5,514 ) (9,245 )

Changes in operating assets and liabilities:

Accounts receivable — (3,045 )

Cash flows from investing activities:

Purchases of property and equipment (171 ) (1,468 )

Net cash provided by (used in) investing activities (1,197 ) 142,570

Cash flows from financing activities:

Proceeds from at-the-market offering, net of commissions of $2,250 72,750 —

Payments of offering costs associated with issuance of common stock (1,150 ) —

Proceeds from issuance of TCG pre-funded warrant — 30,000

Proceeds from sale of future royalties — 15,000

Repurchase of common stock from Bristol-Myers Squibb — (3,000 )

Net cash provided by financing activities 180,566 42,118

Effect of foreign exchange rates on cash and cash equivalents 6 (4 )

Net increase (decrease) in cash and cash equivalents (29,136 ) 8,975

Cash and cash equivalents at beginning of year 44,252 35,277

Cash and cash equivalents at end of year $ 15,116 $ 44,252

Non-cash investing and financing activities:

Supplemental disclosure of cash flow information:

Cash paid (refund) for income taxes, net $ (195 ) $ 76

The accompanying notes are an integral part of these consolidated financial statements.

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NEKTAR THERAPEUTICS

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

December 31, 2025

Note 1 — Organization and Summary of Significant Accounting Policies

Organization

Nektar Therapeutics (Nektar, we) is a clinical stage, research-based drug discovery biopharmaceutical company headquartered in San Francisco, California and incorporated in Delaware, focused on discovering and developing innovative medicines in the field of immunotherapy. Within this growing field, we direct our efforts toward creating new immunomodulatory agents that selectively induce, amplify, attenuate or prevent immune responses in order to achieve desired therapeutic outcomes. Our pipeline of clinical-stage and preclinical-stage immunomodulatory agents targets the treatment of autoimmune diseases (e.g. rezpegaldesleukin and NKTR-0165 and-0166, respectively) and cancer (e.g. NKTR-255). We are conducting Phase 2b trials of rezpegaldesleukin in patients with moderate-to-severe atopic dermatitis which we initiated in October 2023 (the Phase 2b REZOLVE-AD trial) and in patients with severe-to-very severe alopecia areata which we initiated in March 2024 (the Phase 2b REZOLVE-AA trial). On February 24, 2025, we announced that we had entered into a collaboration agreement with TrialNet to evaluate rezpegaldesleukin in patients with new onset stage 3 type 1 diabetes mellitus in a Phase 2 study. TrialNet will conduct the study with funding from the National Institutes of Health, primarily through the Special Statutory Funding Program for Type 1 Diabetes through the National Institute of Diabetes and Digestive and Kidney Diseases. Nektar will supply rezpegaldesleukin for the study and will retain all rights to the rezpegaldesleukin program under the collaboration.

On June 24, 2025 and February 10, 2026, we announced data from the 16-week induction period and 36-week maintenance period, respectively, of the ongoing Phase 2b REZOLVE-AD trial being conducted in 393 patients.

On December 16, 2025, we announced data from the 36-week induction period of the ongoing Phase 2b REZOLVE-AA trial being conducted in 92 patients.

Our research and development activities have required significant ongoing investment to date and are expected to continue to require significant investment. As a result, we expect to continue to incur substantial losses and negative cash flows from operations in the future. We have financed our operations primarily through cash generated from licensing, collaboration and manufacturing agreements and financing transactions. At December 31, 2025, we had approximately $245.8 million in cash and investments in marketable securities.

As we continue our research and development activities, we will need additional cash to fund our operations. Accordingly, we may enter into new collaboration agreements or other similar transactions, and we may also seek financing transactions, which may include dilutive equity-based financings, such as an offering of our common stock. There can be no assurance that any additional collaboration agreements or financings will be available to us on commercially reasonable terms. We believe we have sufficient cash and investments in marketable securities to fund operations through at least the next twelve months from the date of the filing of these financial statements.

We filed a shelf registration statement on Form S-3 and a related prospectus (the April 2025 Shelf Registration Statement) that was declared effective by the Securities and Exchange Commission (the SEC) on April 1, 2025. Pursuant to the April 2025 Shelf Registration Statement, we may offer and sell common stock, preferred stock, debt securities, warrants and or units having an aggregate public offering price of up to $300.0 million. In connection with the filing of the Shelf Registration Statement, we also entered into an equity distribution agreement (the April 2025 ATM Sales Agreement) with Piper Sandler & Co. and BTIG, LLC, relating to the sale of our common stock having an aggregate offering price of up to $75.0 million (the April 2025 ATM Shares). The sales of the ATM shares could be made by any method permitted that is deemed to be an “at-the-market” equity offering as defined in Rule 415(a)(4) promulgated under the Securities Act, including sales made directly on or through Nasdaq or on any other existing trading market for our common stock. We have agreed to pay Piper Sandler & Co. and BTIG, LLC a commission equal to 3.0% of the gross sales price of all common stock sold through them as sales agents.

On July 2, 2025, pursuant to the April 2025 Shelf Registration Statement, we completed the sale and issuance of 4,893,618 shares of our common stock in an underwritten public offering (the 2025 Offering) at a price of $23.50 per share. The net proceeds to the Company from the 2025 Offering totaled approximately $107.2 million, after deducting underwriting discounts and commissions and offering costs. See Note 8 for additional information.

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In September and October 2025, we issued 1,273,923 shares of our common stock under the April 2025 ATM Sales Agreement at a weighted average price of $58.87 per share for net proceeds of $72.5 million after deducting related commissions and offering costs. No shares remain available for issuance under the April 2025 ATM Sales Agreement.

On November 12, 2025, we filed a new registration statement on Form S-3ASR and a related prospectus (the November 2025 Shelf Registration), as a “well-known seasoned issuer,” as defined in Rule 405 under the Securities Act. The November 2025 Shelf Registration became automatically effective upon filing, and permits us to offer, from time to time, an unspecified amount of common stock, preferred stock, debt securities and warrants.

On February 13, 2026, we completed the sale and issuance of 7,637,931 shares of common stock at a price of $58.00 per share and 293,103 pre-funded warrants at price of $57.9999 per pre-funded warrant in an underwritten public offering (the 2026 Offering). The estimated net proceeds from the 2026 Offering totaled approximately $432.0 million, after deducting underwriting discounts and commissions and estimated offering expenses. See Note 8 for additional information.

On November 12, 2025, we also entered into a new equity distribution agreement (the November 2025 ATM Sales Agreement) with Piper Sandler & Co. and BTIG, LLC, relating to the sale of our common stock having an aggregate offering price of up to $110.0 million in an “at-the-market” offering (the November 2025 ATM Shares). As of December 31, 2025, no shares were issued under the November 2025 ATM Sales Agreement. From February 20, 2026 through March 11, 2026, we issued 639,131 shares of our common stock under the November 2025 ATM Sales Agreement at a weighted average price of $71.15 per share for net proceeds of $44.1 million after deducting related commissions of approximately $1.4 million.

Sale of Manufacturing Facility

On December 2, 2024, we completed the sale of our manufacturing facility located in Huntsville, Alabama (the Facility) and certain other manufacturing assets related thereto, including the assignment of our existing manufacturing and supply obligations, to Gannet BioChem, an affiliate of Ampersand Management LLC d/b/a Ampersand Capital Partners (Ampersand), via an Asset Purchase Agreement (the APA), for consideration of $64.7 million in cash, net of transaction costs, and an approximate 20% equity ownership at the time of close in Gannet BioChem. See Note 11 for additional information. As a result of the sale of the Facility, we no longer recognize product sales or cost of goods sold.

Basis of Presentation and Principles of Consolidation

We have prepared our Consolidated Financial Statements pursuant to U.S. generally accepted accounting principles (U.S. GAAP) and the rules and regulations of the Securities and Exchange Commissions.

Our Consolidated Financial Statements include the financial position, results of operations and cash flows of our wholly-owned subsidiaries. In determining whether we are the primary beneficiary of a variable interest entity, we consider whether we have both the power to direct activities of the entity that most significantly impact the entity’s economic performance and the obligation to absorb losses of, or the right to receive benefits from, the entity that could potentially be significant to that entity. We do not have any interests in any variable interest entities of which we are the primary beneficiary. We have eliminated all intercompany accounts and transactions in consolidation.

Our Consolidated Financial Statements are denominated in U.S. dollars. Accordingly, changes in exchange rates between the applicable foreign currency and the U.S. dollar will affect the translation of each foreign subsidiary’s financial results into U.S. dollars for purposes of reporting our consolidated financial results.

Our comprehensive loss consists of our net loss plus our foreign currency translation gains and losses (to the extent recognized in other comprehensive income (loss)) and unrealized holding gains and losses on available-for-sale securities. There were no significant reclassifications out of accumulated other comprehensive income (loss) to the statements of operations during the periods presented. We include translation gains and losses in accumulated other comprehensive income (loss) in the stockholders’ equity section of our Consolidated Balance Sheets. However, if we have concluded that we have substantially liquidated the entity, such as for our subsidiary in India, we recognize subsequent translation gains and losses in other income (expense) in our Consolidated Statements of Operations.

Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Accounting estimates and assumptions are inherently uncertain.

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Actual results could differ materially from those estimates and assumptions. Our estimates include those related to the selling prices of performance obligations and amounts of variable consideration in collaboration agreements, royalty revenue, and other assumptions required for revenue recognition as described further below; the determination of our ability to exercise control or significant influence over our equity method investee; the fair value and impairment of investments in marketable securities, equity method investment, and long-lived assets; contingencies, accrued clinical trial, contract manufacturing and other expenses; income taxes; non-cash royalty revenue and non-cash interest expense from our liabilities related to our sales of future royalties; our assumptions used in stock-based compensation; and ongoing litigation, among other estimates. We base our estimates on historical experience and on other assumptions, including assumptions as to future events, that management believes are reasonable under the circumstances. These estimates form the basis for making judgments about the carrying values of assets and liabilities when these values are not readily apparent from other sources. As appropriate, we assess estimates each period, update them to reflect current information, and generally reflect any changes in estimates in the period first identified.

Fair Value Measurements

The recorded amounts of certain financial instruments, including cash and cash equivalents, accounts receivable, accounts payable and accrued liabilities approximate their fair values due to their relatively short maturities. We record available-for-sale investments and cash equivalents at their estimated fair values, which are based on market prices from a variety of industry standard data providers and generally represent quoted prices for similar assets in active markets or have been derived from observable market data.

Certain assets and liabilities are reported on a recurring basis at fair value, and certain assets and liabilities are subsequently adjusted to their fair values, in accordance with the fair value hierarchy established in ASC 820-10, Fair ValueMeasurements and Disclosures (ASC 820). ASC 820 defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (anexit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The fair value hierarchy of ASC Topic 820 requires an entity to maximize the use of observable inputs when measuring fair value and classifies those inputs into three levels:

Level 1 — Quoted prices in active markets for identical assets or liabilities.

Level 2 — Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted pricesfor identical or similar assets or liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. For the years ended December 31, 2025 and 2024, there were no transfers between Level 1 and Level 2 of the fair value hierarchy.

Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Related Parties

Transactions between related parties are considered to be related party transactions even though they may not be given accounting recognition. ASC 850, Related Party Disclosures (ASC 850) requires that transactions with related parties that would make a difference in decision making shall be disclosed so that users of the financial statements can evaluate their significance. Please see Note 4 regarding our related party transactions with Gannet BioChem.

Cash, Cash Equivalents, and Investments in Marketable Securities

We consider all investments in marketable securities with an original maturity of 90 days or less when purchased to be cash equivalents. We classify investments in securities with remaining maturities of less than one year, or where our intent is to use the investments to fund current operations or to make them available for current operations, as short-term investments. We classify investments in securities with remaining maturities of over one year as long-term investments.

Our cash and investments are held or issued by financial institutions that management believes are of high credit quality. However, we are exposed to credit risk in the event of default by the third parties that hold or issue such assets. Our investment policy limits investments to fixed income securities denominated and payable in U.S. dollars such as corporate bonds, corporate commercial paper, U.S. government obligations, and money market funds and places restrictions on maturities and concentrations by type and issuer.

For our available-for-sale securities, we have significant concentrations of issuers in the banking and financial services industry. While our investment policy requires that we only invest in highly-rated securities and limit our exposure

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to any single issuer, a variety of factors may materially affect the financial condition of issuers. Additionally, pursuant to our investment policy, we may sell securities before maturity if the issuer’s credit rating has been downgraded below our minimum credit rating requirements, which may result in a loss on the sale. Accordingly, if factors result in downgrades below our minimum credit rating requirements and if we decide to sell these securities, we may experience losses on such sales.

Investments are designated as available-for-sale and are carried at fair value with unrealized gains and losses reported in stockholders’ equity as accumulated other comprehensive income (loss). We review our portfolio of available-for-sale debt securities, using both quantitative and qualitative factors, to determine if declines in fair value below amortized cost have resulted from a credit-related loss or other factors. If the decline in fair value is due to credit-related factors, we recognize a loss in our Consolidated Statements of Operations, whereas if the decline in fair value is not due to credit-related factors, we recognize the loss in other comprehensive income (loss).

We include coupon interest on securities classified as available-for-sale, as well as amortization of premiums and accretion of discounts to maturity, in interest income. The cost of securities sold is based on the specific identification method.

Accounts Receivable and Significant Customer Concentrations

Our customers are primarily pharmaceutical and biotechnology companies with whom we have multi-year arrangements. Before the sale of the Facility, our accounts receivable balance primarily contained trade receivables from product sales. We have not recorded provisions for credit losses for any of the periods presented. Accounts receivable at December 31, 2025 and December 31, 2024 are immaterial due to the sale of the Facility.

Inventory and Significant Supplier Concentrations

Before the sale of Facility, we manufactured inventory upon receipt of firm purchase orders from our partners, and we manufactured certain intermediate work-in-process materials and purchased raw materials based on purchase forecasts from our partners. Inventory included direct materials, direct labor, and manufacturing overhead, and we determined cost on a first-in, first-out basis for raw materials and on a specific identification basis for work-in-process and finished goods. We valued inventory at the lower of cost or net realizable value, and we wrote down defective or excess inventory to net realizable value based on historical experience or projected usage. We expensed inventory related to our research and development activities when we purchased or manufactured it. We have no inventory balance at December 31, 2025 and December 31, 2024 due to the sale of the Facility.

We are dependent on our suppliers and contract manufacturers to provide raw materials and drugs of appropriate quality and reliability and to meet applicable contract and regulatory requirements. In certain cases, we rely on single sources of supply of one or more critical materials. As a result of the sale of the Facility, we are dependent on Gannet BioChem for the supply of the polyethylene glycol reagents (PEG reagents) used in the manufacture of rezpegaldesleukin and NKTR-255. Consequently, in the event that supplies are delayed or interrupted for any reason, our ability to develop and produce our drug candidates could be significantly impaired, which could have a material adverse effect on our business, financial condition and results of operations.

Long-Lived Assets

We report property and equipment at cost, net of accumulated depreciation. We capitalize major improvements and expense maintenance and repairs as incurred. We generally recognize depreciation on a straight-line basis. We depreciate manufacturing, laboratory and other equipment over their estimated useful lives of generally three to ten years, depreciate buildings over the estimated useful life of generally twenty years and amortize leasehold improvements over the shorter of the estimated useful lives or the remaining term of the related lease.

We assess the impairment of long-lived assets whenever events or changes in business circumstances indicate that the carrying amounts of the assets may not be fully recoverable. In the case of property and equipment and right-of-use assets for our leases, we determine whether there has been an impairment by comparing the carrying value of the asset to the anticipated undiscounted net cash flows associated with the asset. If such cash flows are less than the carrying value, we write down the asset to its fair value, which may be measured as anticipated net cash flows associated with the asset, discounted at a rate that we believe a market participant would utilize to reflect the risks associated with the cash flows, such as credit risk.

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See Note 10 for additional information regarding the impairment charges we recorded for our leased facilities and certain property and equipment.

Leases

We determine if an arrangement contains a lease at the inception of the arrangement. Right-of-use assets represent our right to use an underlying asset for the lease term, and lease liabilities represent our obligation to make lease payments arising from the lease. We recognize operating lease right-of-use assets and liabilities at the lease commencement date based on the present value of lease payments over the expected lease term. In determining the present value of lease payments, we use our incremental borrowing rate based on the information available at the lease commencement date. Our expected lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise any such options. We have elected to recognize lease incentives, such as tenant improvement allowances, at the lease commencement date as a reduction of the right-of-use asset and lease liability until paid to us by the lessor to the extent that the lease provides a specified fixed or maximum level of reimbursement and we are reasonably certain to incur reimbursable costs at least equaling such amounts.

We have elected the practical expedient to account for the lease and non-lease components, such as common area maintenance charges, as a single lease component for our facilities leases, and elected the short-term lease recognition exemption for our short-term leases, under which we do not recognize lease liabilities and right-of-use assets for leases with an original term of twelve months or less.

We recognize lease expense for our operating leases on a straight-line basis over the expected lease term. However, if we recognize an impairment of our right-of-use assets, the subsequent lease expense of such lease is recognized on an accelerated basis as lease expense includes the recognition of accretion expense on our lease liability, which is higher in earlier periods due to the higher lease liability, and straight-line amortization of the remaining post-impairment right-of-use asset.

Please see Note 5 for additional information regarding our leases.

Restructuring

In April 2022 and April 2023, we announced certain restructuring plans (the 2022 Restructuring Plan and the 2023 Restructuring Plan, respectively), pursuant to which we terminated significant portions of our workforce and decided to sublease all of our leased premises in San Francisco, California, including our office space on Third St. (Third St. Facility) and our office and laboratory space on Mission Bay Blvd. South (Mission Bay Facility).

We recognize restructuring charges related to reorganization plans that have been committed to by management when liabilities have been incurred. In connection with these activities, we record restructuring charges at fair value for contract termination costs incurred when we cancel the contract in accordance with its terms, or for costs to be incurred over the remaining contract term without economic benefit to us at the cease-use date. See Note 10 for additional information.

Reverse Stock Split

On June 6, 2025, we filed a Certificate of Amendment to the Certificate of Incorporation, or the Reverse Stock Split Amendment, to effect a reverse stock split of Nektar’s Common Stock at a ratio of one-for-fifteen, effective June 8, 2025. No fractional shares of common stock were issued as a result of the Reverse Stock Split. All share and per share figures in these financial statements have been adjusted to give retrospective effect to the Reverse Stock Split. See Note 8 for additional information.

Treasury Stock

We record treasury stock activities under the cost method. Treasury stock is included in authorized and issued shares but excluded from outstanding shares. The re-issuance of treasury stock is accounted for on a first-in, first-out basis and any differences between the cost of treasury stock and the re-issuance proceeds are charged or credited to additional paid-in capital. In connection with the 2025 Offering, we re-issued all shares held in treasury stock. See Note 8 for additional information.

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Collaborative Arrangements

We enter into collaboration arrangements with pharmaceutical and biotechnology collaboration partners, under which we may grant licenses to our collaboration partners to further develop and commercialize one of our drug candidates, either alone or in combination with the collaboration partners’ compounds. We may also perform research, development, manufacturing and supply activities under our collaboration agreements. Consideration under these contracts may include an upfront payment, development and regulatory milestones and other contingent payments, expense reimbursements, royalties based on net sales of approved drugs, and commercial sales milestone payments. Additionally, these contracts may provide options for the customer to purchase additional contract research and development services under separate contracts.

When we enter into collaboration agreements, we assess whether the arrangements fall within the scope of ASC 808, Collaborative Arrangements (ASC 808) based on whether the arrangements involve joint operating activities and whether both parties have active participation in the arrangement and are exposed to significant risks and rewards of the arrangement. To the extent that the arrangement falls within the scope of ASC 808, we assess whether the payments between us and our collaboration partner fall within the scope of other accounting literature. If we conclude that payments from the collaboration partner to us represent consideration from a customer, such as license fees and contract research and development activities, we account for those payments within the scope of ASC 606, Revenue from Contracts with Customers (ASC 606). However, if we conclude that our collaboration partner is not a customer for certain activities and associatedpayments, such as for certain collaborative research, development, manufacturing and commercial activities, we present such payments as a reduction of research and development expense or general and administrative expense, based on where we present the underlying expense.

Revenue Recognition

For elements of those arrangements that we determine should be accounted for under ASC 606, we assess which activities in our collaboration agreements are performance obligations that should be accounted for separately and determine the transaction price of the arrangement, which includes the assessment of the probability of achievement of future milestones and other potential consideration. For arrangements that include multiple performance obligations, such as granting a license or performing contract research and development activities or participation on joint steering or other committees, we allocate upfront and milestone payments under a relative standalone selling price method. Accordingly, we develop assumptions that require judgment to determine the standalone selling price for each performance obligation identified in the contract. These key assumptions may include revenue forecasts, clinical development timelines and costs, discount rates and probabilities of clinical and regulatory success.

Product sales

As a result of the sale of the Facility, we no longer recognize product sales of PEG reagents.

Before the sale of the Facility, product sales were primarily derived from manufacturing and supply agreements we entered into with our customers. We have assessed our manufacturing and supply arrangements and have generally determined that they provided the customer an option to purchase our proprietary PEG reagents. Accordingly, we treated each purchase order as a discrete exercise of the customer’s option (i.e. a separate contract) rather than as a component of the overall arrangement. The pricing for the manufacturing and supply was generally at a fixed price. The “take or pay” arrangement signed with UCB during 2024 resulted in recognition based on a single sales price over multiple years. See Note 9 for additional details.

We invoiced and recognized product sales when title and risk of loss passed to the customer, which generally occurred upon shipment. Customer payments were generally due 30 days from receipt of an invoice. We tested our products for adherence to technical specifications before shipment; accordingly, we have not experienced any significant returns from our customers. We recognized costs related to shipping and handling of product to customers in cost of goods sold.

Non-cash royalty revenue

Generally, for our collaboration arrangements that include sales-based royalties, we have granted our collaboration partner a license to our intellectual property. Pursuant to these arrangements, our collaboration partners are typically obligated to pay a royalty that is based on the net sales of their approved drugs that are sold in the countries where we have intellectual property rights covering their drugs. We have sold our rights to receive sales-based royalties for CIMZIA®, MIRCERA®,MOVANTIK®, ADYNOVATE® and REBINYN® as further described in Note 6. For collaboration arrangements that include sales-based royalties, we have concluded that the license is the predominant item to which the royalties relate, which include commercial milestone payments based on the level of sales. Accordingly, we recognize royalty revenue when the underlying sales occur based on our best estimates of sales of the drugs. Our aggregate non-cash

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royalty revenue of $54.9 million and $64.3 million for the years ended December 31, 2025 and 2024, respectively, represents revenue for granting licenses for which we had satisfied in prior periods.

License, collaboration and other revenue

License Grants: For collaboration arrangements that include a grant of a license to our intellectual property, we consider whether the license grant is distinctfrom the other performance obligations included in the arrangement. Generally, we would conclude that the license is distinct if the customer is able to benefit from the license with the resources available to it. For licenses that are distinct, we recognize revenues from non-refundable, upfront payments and other consideration allocated to the license when the license term has begun and we have provided all necessary information regarding the underlying intellectual property to the customer, which generally occurs at or near the inception of the arrangement.

Milestone Payments: At the inception of the arrangement and at each reporting date thereafter, we assess whether we should include any milestone payments orother forms of variable consideration in the transaction price, based on whether a significant reversal of revenue previously recognized is not probable upon resolution of the uncertainty. Since milestone payments may become payable to us upon the initiation of a clinical study, filing for or receipt of regulatory approval or the first commercial sale of a product, we review the relevant facts and circumstances to determine when we should update the transaction price, which may occur before the triggering event. When we do update the transaction price for milestone payments, we allocate it on a relative standalone selling price basis and record revenue on a cumulative catch-up basis, which results in recognizing revenue for previously satisfied performance obligations in such period. If we update the transaction price before the triggering event, we recognize the increase in the transaction price as a contract asset. Our partners generally pay development milestones after achievement of the triggering event.

Research and Development Services: For amounts allocated to our research and development obligations in a collaboration arrangement, we recognize revenueover time using a proportional performance model, representing the transfer of goods or services as we perform activities over the term of the agreement.

Research and Development Expense

Research and development costs are expensed as incurred and include salaries, benefits and other operating costs such as outside services, supplies and allocated overhead costs.

We record an accrued expense for the estimated unbilled costs of our clinical study activities performed by third parties. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows to our vendors. Payments under the contracts depend on factors such as the achievement of certain events, successful enrollment of patients and completion of certain clinical trial activities. We generally recognize costs associated with the start-up and reporting phases of the clinical trials as incurred. We generally accrue costs associated with the treatment phase of clinical trials based on the estimated activities performed by our third-party vendors, including our contract research organizations. In specific circumstances, such as for certain time-based costs, we recognize clinical trial expenses ratably over the service period, as we believe that this methodology may be more reflective of the timing of costs incurred.

We capitalize advance payments for goods or services that will be used or rendered for future research and development activities and recognize expense as the related goods are delivered or services performed.

Non-cash Interest Expense on Liabilities Related to the Sales of Future Royalties

Interest expense on liabilities related to the sales of future royalties is imputed on the unamortized portion using the effective interest method. We periodically assess the estimated royalty payments under our licensees, and, as the amount or timing of such payments of these estimates change, we prospectively adjust the imputed interest rate and the related amortization of the respective liability. The actual interest rate will be affected by the timing of the royalty payments and changes in the forecasted revenue.

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Equity Method Investment

Our investment in Gannet BioChem is considered a variable interest entity for which we are not the primary beneficiary. We use the equity method of accounting to account for our investment in Gannet BioChem, which is an entity that we do not control, but have the ability to exert significant influence. Judgments regarding the level of influence over the equity method investment include consideration of key factors such as our ownership interest, representation on the board of directors or participation in policy-making decisions.

Under the equity method of accounting, our investment in Gannet BioChem was initially recorded at fair value on our Consolidated Balance Sheets. The carrying value of the investment is subsequently adjusted based on our share of the net income or loss of the entity which we present as gain or loss from equity method investment in our Consolidated Statements of Operations. We record our share of the equity method investment’s results of operations on a three-month lag basis, as further disclosed in Note 4.

Due to Ampersand’s right to receive a cumulative preferred dividend at a certain annual rate of return and return of capital before any distributions are made to us as further disclosed in Note 4, we record our gain or loss on our investment in Gannet BioChem under the hypothetical liquidation at book value (HLBV) method.

The HLBV method is a balance sheet approach that calculates the change in the hypothetical amount Ampersand and we would be entitled to receive if Gannet BioChem were liquidated at book value at the end of each period, adjusted for any contributions made and distributions received during the period, as well as basis differences between the initial fair value of our investment in Gannet BioChem and our claim on the net assets of Gannet BioChem. Our maximum exposure to loss in Gannet BioChem is limited to the carrying value of our investment. Loss from our investment in Gannet BioChem of $8.7 million has been recorded for the year ended December 31, 2025.

We evaluate our equity method investment at the end of each reporting period to determine whether events or changes in business circumstances indicate that the carrying value of the investment may not be recoverable. This evaluation consists of several qualitative and quantitative factors that may include recent financial results, projected financial results and operating trends of the investees and other publicly available information that may affect the value of our investment.

Stock-Based Compensation

Stock-based compensation arrangements include grants of stock options and restricted stock units (RSUs) under our equity incentive plans, as well as shares issued under our Employee Stock Purchase Plan (ESPP), through which employees may purchase our common stock at a discount to the market price.

We expense the grant date fair value of stock-based compensation on a straight-line basis over the requisite service periods in our Consolidated Statements of Operations and recognize forfeitures as they occur. For options and RSUs that vest upon the achievement of performance milestones, we recognize expense provided that we believe that the performance milestones are probable of achievement, and we estimate the vesting period based on our evaluation of the estimated date of achievement of these milestones. We report expense amounts in cost of goods sold, research and development expense, and general and administrative expense based on the function of the applicable employee. We estimate the grant date fair value of our stock-based compensation awards as follows:

•

Stock options - We use the Black-Scholes option pricing model for the respective grant to determine the grant date fair value of stock options and common stock issued under the Company’s equity incentive plans or purchased under the ESPP. The Black-Scholes option pricing model requires the input of assumptions, including but not limited to, the expected term of the options, which we may estimate based on actual and projected employee stock option exercise behaviors, and our stock price volatility over the term of the awards.

•

RSUs - The fair value of an RSU is equal to the closing price of our common stock on the grant date.

Income Taxes

We account for income taxes under the liability method. Under this method, we determine deferred tax assets and liabilities based on differences between the financial reporting and tax reporting bases of assets and liabilities, measured using laws and enacted tax rates that we expect to be in effect when we expect the differences to reverse. Realization of deferred tax assets is dependent upon future earnings, the timing and amount of which are uncertain. We record a valuation allowance against deferred tax assets to reduce their carrying value to an amount that is more likely than not to be realized. When we establish or reduce the valuation allowance related to the deferred tax assets, our provision for income taxes will increase or decrease, respectively, in the period we make such determination.

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We utilize a two-step approach to recognize and measure uncertain tax positions. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained upon tax authority examination, including resolution of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount of benefit, determined on a cumulative probability basis, that is more than 50% likely of being realized upon ultimate settlement.

For the years ended December 31, 2025 and 2024, our income tax benefit was immaterial.

Net Loss Per Share

For all periods presented in the Consolidated Statements of Operations, the net loss available to common stockholders is equal to the reported net loss. We calculate basic net loss per share based on the weighted-average number of common shares outstanding, including the TCG Pre-funded Warrant, during the periods presented. Before the exercise of the TCG Pre-funded Warrant, shares of common stock underlying the TCG Pre-funded Warrant were considered outstanding for the purposes of computing basic net loss per share because the shares were issuable for little consideration, were fully vested and were exercisable after the original issuance date. For the years ended December 31, 2025 and 2024, basic and diluted net loss per share are the same due to our net losses and the requirement to exclude potentially dilutive securities which would have an antidilutive effect on net loss per share. We excluded shares underlying the weighted average outstanding stock options and RSUs, as follows:

Year Ended December 31,

Comprehensive Loss

Comprehensive loss is the change in stockholders’ equity from transactions and other events and circumstances other than those resulting from investments by stockholders and distributions to stockholders. Our comprehensive loss includes our net loss, gains and losses from the foreign currency translation of the assets and liabilities of our foreign subsidiaries, and unrealized gains and losses on investments in available-for-sale securities.

Recent Accounting Pronouncements

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which will require incremental income tax disclosures on an annual basis for all public entities. The amendments require that public business entities disclose specific categories in the rate reconciliation and provide additional information for reconciling items meeting a quantitative threshold. The amendments also require disclosure of income taxes paid to be disaggregated by jurisdiction, and disclosure of income tax expense disaggregated by federal, state, and foreign. ASU 2023-09 is effective for annual reporting beginning with the fiscal year ending December 31, 2025. We have adopted ASU-2023-09 on a prospective basis for the year ended December 31, 2025. Please refer to Note 13 for further details.

In November 2024, the FASB issued ASU No. 2024-03, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, an accounting standard update that requires the Company to disclose more detailed information about the types of expenses (including employee compensation, depreciation, and amortization) included in each relevant income statement expense caption. In January 2025, the FASB issued ASU 2025-01, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date, to clarify the effective date of ASU 2024-03. The ASU is effective for fiscal years beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. Early adoption is permitted. We are currently evaluating the incremental disclosures that will be required in our consolidated financial statements.

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Note 2 — Cash and Investments in Marketable Securities

Cash and investments in marketable securities, including cash equivalents, are as follows (in thousands):

Estimated Fair Value at

December 31, December 31,

Long-term investments — 13,869

Total cash and investments in marketable securities $ 245,752 $ 269,095

We invest in liquid, high quality debt securities. Our investments in debt securities are subject to interest rate risk. To minimize the exposure due to an adverse shift in interest rates, we invest in securities with maturities of two years or less and maintain a weighted average maturity of one year or less. We currently do not intend to sell these securities prior to maturity and it is more likely than not that we will not be required to sell these securities before we recover the amortized cost basis.

During the years ended December 31, 2025 and 2024, we did not sell any available-for-sale securities.

We report our accrued interest receivable, which totaled $0.6 million and $1.1 million at December 31, 2025 and 2024, respectively, in other current assets on our Consolidated Balance Sheets.

Our portfolio of cash and investments in marketable securities includes (in thousands):

Total cash and investments in marketable securities $ 245,752 $ 269,095

At December 31, 2024, our gross unrealized gains and losses were insignificant. As of December 31, 2025 and 2024, we assessed our marketable securities with unrealized losses and concluded that the losses were not attributable to credit. For the twelve months ended December 31, 2025 and 2024, there were no transfers between Level 1 and Level 2 of the fair value hierarchy. As of December 31, 2025, we had 19 investments in unrealized loss positions and no investments had been in continuous unrealized loss positions for 12 months or longer. Accordingly, we have not recorded an allowance for credit losses for these securities.

At both December 31, 2025 and 2024, we had letter of credit arrangements in favor of our landlords and certain vendors totaling $7.8 million and $7.5 million, respectively. These letters of credit are secured by investments of similar amounts.

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Note 3 — Consolidated Financial Statement Details

Other Current Assets

Other current assets consists of the following (in thousands):

December 31,

Prepaid research and development expenses $ 16,540 $ 1,947

Interest and other non-trade receivables 1,779 1,609

Accrued Expenses

Accrued expenses consist of the following (in thousands):

December 31,

Accrued research and development expenses $ 13,980 $ 14,453

Accrued contract termination costs 2,632 2,767

Note 4 — Equity Method Investment

As discussed in Note 1, on December 2, 2024, we completed the sale of the Facility and certain other manufacturing assets related thereto, including the assignment of our existing manufacturing and supply obligations, to Gannet BioChem, an affiliate of Ampersand, via the APA, for consideration of $64.7 million in cash, net of transaction costs, and an equity interest in Gannet BioChem.

We own 20.0 million common units of Gannet BioChem at $1.00 per unit, representing 100% of the common units outstanding at both closing of the sale of the Facility and at December 31, 2025, and Ampersand owns 81.5 million preferred units at $1.00 per unit, representing 100% of the preferred units outstanding at closing and 99.7% of the preferred units outstanding as of December 31, 2025. Gannet BioChem has reserved 11.3 million appreciation rights for issuance to its officers, employees, directors and consultants, which may only be settled upon a “company sale” as defined by Gannet BioChem’s equity plan and convert to common units in determining their distribution, less the “base value”, which is equal to the fair value of the common units as determined by Gannet BioChem’s board of directors. As of December 31, 2025, Gannet BioChem has issued 8.4 million stock appreciation rights, which have a $1.00 base value.

In the event of a distribution, to the extent available, the preferred unitholders have priority rights to a cumulative preferred dividend at a certain annual rate of return and a return of their investment before any distributions to common unitholders. After such priority distribution to the preferred unitholders, to the extent available, common unitholders are to receive a distribution of both a cumulative dividend at the same rate as the preferred unitholders’ dividend and a return of their investment, which, for our common units, is equal to $20.0 million (or $1.00 per unit). Any distributions in excess of both of these distributions, if available, are distributed to preferred and common unitholders pro rata.

We have significant influence, but do not control, Gannet BioChem through our noncontrolling representation on Gannet BioChem’s board of directors and our equity interests in Gannet BioChem. Accordingly, we do not consolidate Gannet BioChem and account for our investment in Gannet BioChem using the equity method of accounting. We record our share of Gannet BioChem’s gains and losses under the HLBV basis, which reflects Ampersand’s liquidation preferences as described above. The HLBV method is a balance sheet approach that calculates the change in the hypothetical amount we and Ampersand would be entitled to receive if Gannet BioChem were liquidated at book value, adjusted for any contributions made and distributions received during the period, as well as basis differences between the initial fair value of our investment

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in Gannet BioChem and our claim on the net assets of Gannet BioChem. Our loss from our investment in Gannet BioChem for the twelve months ended December 31, 2025 is as follows (in thousands):

Claim on net assets of Gannet BioChem - beginning of period $ 12,218

Claim on net assets of Gannet BioChem - end of period 3,491

Change in claim on net assets of Gannet BioChem $ (8,727 )

Gannet BioChem is considered a related party to Nektar. Concurrently with the closing of the transaction, we entered into certain ancillary agreements with Gannet BioChem, including supply agreements for rezpegaldesleukin and NKTR-255, and certain services agreements.

Supply Agreements

Under the terms of the supply agreements, Gannet BioChem has agreed to manufacture and supply the PEG reagents for use in clinical trials of these drug candidates at prices defined within the agreements. There are no minimum purchase commitments and Nektar can terminate the agreement for convenience upon prior written notice. For the twelve months ended December 31, 2025, we recorded $0.7 million as research and development expense for services provided by Gannet BioChem to us in our Consolidated Statements of Operations under the supply agreements.

Services Agreements

Pursuant to a transition services agreement and full-time employee equivalent agreement, Nektar is performing certain transition services for the benefit of Gannet BioChem, primarily related to information technology and accounting, and Gannet BioChem is performing certain services for the benefit of Nektar, primarily to support research and development activities. The terms of these agreements are no more than two years, subject to certain termination provisions. For the twelve months ended December 31, 2025, we recorded $1.9 million as research and development expense for services provided by Gannet BioChem to us in our Consolidated Statements of Operations. For the twelve months ended December 31, 2025, we recorded $1.1 million as other income in our Consolidated Statements of Operations for services provided by us to Gannet BioChem.

As of December 31, 2025, we recorded a net receivable of $0.4 million from Gannet BioChem and payables of $1.1 million to Gannet BioChem, consisting of amounts billable under the services agreements. We report the net receivable in other current asset and the payables in accounts payable and accrued expenses, respectively, in our Consolidated Balance Sheets.

Note 5 — Operating Leases

Our leases consist of a Lease Agreement (the Mission Bay Lease) with ARE-San Francisco No. 19, LLC (ARE) for our 155,215 square foot corporate office and R&D facility located at 455 Mission Bay Boulevard South, San Francisco, California (the Mission Bay Facility) and a Lease Agreement (the Third Street Lease) with Kilroy Realty Finance Partnership, L.P. (Kilroy) for an additional 135,936 square foot of office space at 360 Third Street, San Francisco, California (the Third Street Facility). Both leases terminate on January 31, 2030, subject to two consecutive five year renewal options for the Mission Bay Facility and onefive year renewal option for the Third Street Facility. Other key terms include the following:

•

The monthly base rent for both facilities will escalate over the term of the lease at various intervals.

•

Both leases include various covenants, indemnities, defaults, termination rights, letters of credit and other provisions customary for lease transactions of this nature.

•

During the term of the Mission Bay Lease, we are responsible for paying our share of operating expenses specified in the lease, including utilities, common area maintenance, insurance costs and taxes.

•

For the Third Street Lease, our fixed annual base rent on an industrial gross lease basis includes certain expenses and property taxes paid directly by the landlord.

Due to our 2022 and 2023 Restructuring Plans, during the years ended December 31, 2025 and 2024, we recorded impairment charges of $3.8 million and $7.3 million, respectively, for our right-of-use assets which we are seeking to sublease. See Note 10 for additional information.

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We generally recognize lease expense for our operating leases on a straight-line basis over the lease term. For spaces where we have recognized an impairment charge, the aggregate lease expense recognized over the remaining term is reduced by the amount of the impairment charge, but we recognize the remaining lease expense on an accelerated basis. The components of lease expense, which we include in general and administrative expense in our Consolidated Statements of Operations, were as follows (in thousands):

Year Ended December 31,

During the years ended December 31, 2025 and 2024, we paid $22.3 million and $21.6 million, respectively, of operating lease payments related to our lease liabilities, which we include in net cash used in operating activities in our Consolidated Statements of Cash Flows.

As of December 31, 2025, the maturities of our operating lease liabilities were as follows (in thousands):

Year ending December 31,

Total lease payments 96,508

Less: portion representing interest (10,757 )

Operating lease liabilities 85,751

Less: current portion (20,495 )

Operating lease liabilities, less current portion $ 65,256

As of December 31, 2025, the weighted-average remaining lease term is 4.1 years and the weighted-average discount rate was 5.8%.

We have entered into subleases for approximately 29,000 square feet of space in our Mission Bay Facility that provide for fixed lease payments, as well as full recovery of the subtenants’ share of operating expenses under our master lease agreement, subject to certain free rent periods. We record the total sublease income as a reduction of general and administrative expense, which totaled $3.7 million and $3.2 million for the years ended December 31, 2025 and 2024, respectively.

As of December 31, 2025, maturities of our operating lease receivables from subleases for each of the next five years and thereafter were as follows:

Year ending December 31,

2030 and thereafter —

Gross lease receivable $ 7,033

Note 6 — Liabilities Related to the Sales of Future Royalties

On February 24, 2012, for gross proceeds of $124.0 million, we entered into a purchase and sale agreement (the 2012 Purchase and Sale Agreement) with RPI Finance Trust (RPI), an affiliate of Royalty Pharma, pursuant to which we sold, and RPI purchased, our right to receive royalty payments (the 2012 Transaction Royalties) arising from the worldwide net sales, from and after January 1, 2012, of (a) CIMZIA®, under our license, manufacturing and supply agreement with UCB Pharma (UCB), and (b) MIRCERA®, under our license, manufacturing and supply agreement with F. Hoffmann-La Roche Ltd and Hoffmann-La Roche Inc. (together referred to as Roche). As a result of our ongoing manufacturing and supply obligations related to the generation of these royalties, we recorded the proceeds as debt, and we recognize non-cash royalty revenue, as

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royalties from the CIMZIA® and MIRCERA® products are remitted directly to RPI, and non-cash interest expense to amortize the liability using the effective interest method over the estimated life of the 2012 Purchase and Sale Agreement.

We were required to pay RPI an aggregate $10.0 million as a result of worldwide net sales of MIRCERA® during the years 2013 and 2012 not reaching certain minimum thresholds. The 2012 Purchase and Sale Agreement does not include any other potential payments related to minimum net sales thresholds.

On June 5, 2020, UCB served notice of a Declaratory Judgment of Patent Invalidity, filed in the United States District Court for the District of Delaware, seeking a declaration of invalidity of certain of our patents that we had licensed to UCB and pursued similar actions in other jurisdictions. On October 14, 2021, RPI and we entered into a Letter Agreement which permitted us to enter into a Settlement Agreement, effective October 13, 2021, with UCB to effect the negotiation between RPI and UCB in which UCB and RPI agreed to a reduction in the royalty term and annual decreases in the royalty rate over the remaining royalty term in exchange for UCB’s withdrawal of all of UCB’s litigation and challenges.

We concluded that we should account for the decrease in royalty payments to RPI as a result of these agreements as a modification of our liability. Due to the significance of the change in the estimated royalty payments, we concluded that we should treat the modification as an extinguishment of the prior liability and recognize a new liability based on the revised royalty payments and term, discounted to fair value. Accordingly, we estimated the fair value to be approximately $84.7million. As a result, we recognized a non-cash loss of $23.5 million on the revaluation of the prior liability in the three months ended December 31, 2021, and we wrote off the remaining $0.9 million of unamortized transaction costs.

On December 16, 2020, for gross proceeds of $150.0 million, we entered into a capped purchase and sale agreement (the 2020 Purchase and Sale Agreement) with entities managed by Healthcare Royalty Management, LLC (collectively, HCR). Pursuant to the 2020 Purchase and Sale Agreement, we agreed to sell to HCR certain of our rights to receive royalty payments arising from the worldwide net sales, from and after October 1, 2020, of (a) MOVANTIK® under our license agreement with AstraZeneca AB (Astra Zeneca), as amended, (b) ADYNOVATE® under our research, development, license and manufacturing and supply agreement with Baxalta US Inc. and Baxalta GmbH (collectively, Baxalta), as amended, (c) REBINYN® under our settlement and license agreement with Novo Nordisk Inc., Novo Nordisk A/S and Novo Nordisk A/G and (d) licensed products under that our right to sublicense agreement with Baxalta. As a result of the cap on the royalties to be received by HCR and our ongoing manufacturing and supply obligations related to the generation of these royalties, we recorded the proceeds as debt, and we recognize non-cash royalty revenue, as royalties from these products are remitted directly to HCR, and non-cash interest expense to amortize the liability using the effective interest method over the estimated life of the 2020 Purchase and Sale Agreement. As of December 31, 2025, our prospective effective interest rate used to amortize the liability is 49.2%.

The original 2020 Purchase and Sale Agreement was to expire -- and wherein the right to receive royalties would revert to us -- if HCR received aggregate royalties of $210.0 million on or prior to December 31, 2025 (the 2025 Threshold), or, if the 2025 Threshold was not achieved by December 31, 2025, when HCR received aggregate royalties of $240.0 million. On March 4, 2024, Nektar and HCR amended the original 2020 Purchase and Sale Agreement (the Amendment), pursuant to which the parties agreed to remove our reversionary rights in the royalties in exchange for a $15.0 million payment from HCR. Accordingly, HCR will receive all future royalties of the products, and none of these royalties will return to Nektar. We accounted for the Amendment as a modification of the existing arrangement, and therefore recorded the $15.0 million proceeds as an increase to the liability.

The sale of the Facility did not alter the 2012 or the 2020 Purchase and Sale Agreements, nor royalties payable under the related license agreements.

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The following table shows the activity within the liability account of each arrangement (in thousands):

Year-EndedDecember 31, 2025 Period from inception toDecember 31, 2025

Less: unamortized transaction costs — (814 ) (814 ) — (814 ) (814 )

Note 7 — Commitments and Contingencies

Purchase Commitments

In the normal course of business, we enter into various firm purchase commitments related to contract manufacturing, clinical development and certain other items. As of December 31, 2025, these commitments were approximately $3.7 million.

Legal Matters

From time to time, we are involved in lawsuits, arbitrations, claims, investigations and proceedings, consisting of intellectual property, commercial, employment and other matters, which arise in the ordinary course of business. We make provisions for liabilities when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Such provisions are reviewed at each reporting date and adjusted to reflect the impact of settlement negotiations, judicial and administrative rulings, advice of legal counsel, and other information and events pertaining to a particular case. Litigation is inherently unpredictable. If any unfavorable ruling were to occur in any specific period, there exists the possibility of a material adverse impact on the results of our operations for that period and on our cash flows and liquidity.

On August 7, 2023, we filed a complaint in the United States District Court for the Northern District of California (the Court) against Eli Lilly and Company (Lilly) alleging, among other claims, breach of contract and breach of implied covenant of good faith and fair dealing (the Complaint), in connection with our collaboration with Lilly. Following the denial of its motion to dismiss the Complaint entirely, Lilly filed an answer that included counterclaims against us alleging breach of specified confidentiality provisions and defamation. On September 19, 2025, Lilly filed a motion to voluntarily dismiss its counterclaims with prejudice, which the Court granted on October 7, 2025. Lilly has filed a motion for summary judgment, and the court has not yet issued a decision on this motion, as well as other pre-trial motions filed by both parties that remain pending before the Court. Following the shutdown of the federal government, on October 14, 2025, the Court postponed the previously calendared October 27, 2025 starting date of the jury trial. The Court has set a new jury trial date of September 8, 2026.

After previously authorizing and paying good and service tax (GST) refunds of approximately $3.3 million for the period of July 2017 to September 2019, the Indian GST authorities issued a show cause notice in October 2023 seeking to recover this refund, plus penalties and interest, for which we have subsequently received a demand in September 2025 seeking payment to Indian GST authorities. We have not paid the demand in view of an appeal we filed with the Indian authorities, and believe that we have meritorious defenses against the demand. We believe a loss is not probable and therefore have not accrued a liability as of December 31, 2025.

On March 6, 2026, a putative class action complaint was filed in the U.S. District Court for the Northern District of California against the Company, our CEO, CFO and Chief Research and Development Officer, captioned Schramke v. Nektar Therapeutics, et al. The complaint asserts claims for violations of Sections 10(b) and 20(a) of the Securities Exchange Act and SEC rules promulgated thereunder, seeks damages, attorneys’ fees and other relief, and alleges, among other things, that from February 26, 2025 through December 15, 2025, the defendants made misleading statements and/or failed to

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disclose material information regarding the REZOLVE-AA trial. The Company denies the claims, believes they are without merit, and intends to defend vigorously against this litigation. We have not recorded a liability for this matter as of December 31, 2025.

We have recorded no liability for any litigation matters in our Consolidated Balance Sheets at either December 31, 2025 or December 31, 2024.

Indemnification Obligations

During the course of our normal operating activities, we have agreed to certain contingent indemnification obligations as further described below. The term of our indemnification obligations is generally perpetual. There is generally no limitation on the potential amount of future payments we could be required to make under these indemnification obligations. To date, we have not incurred significant costs to defend lawsuits or settle claims based on our indemnification obligations. If any of our indemnification obligations is triggered, we may incur substantial liabilities. Because the aggregate amount of any of these potential indemnification obligations is not a stated amount, we cannot reasonably estimate the overall maximum amount of any such obligations. We have recorded no liabilities for these obligations in our Consolidated Balance Sheets at either December 31, 2025 or December 31, 2024.

Indemnifications in Connection with Commercial Agreements

As part of our collaboration agreements with our partners related to the license, development, manufacture and supply of our proprietary drug candidates, we generally agree to defend, indemnify and hold harmless our partners from and against third party liabilities arising out of the agreement, including product liability (with respect to our activities) and infringement of intellectual property to the extent the intellectual property is developed by us and licensed to our partners. The term of these indemnification obligations is generally perpetual commencing after execution of the agreement. There is generally no limitation on the potential amount of future payments we could be required to make under these indemnification obligations.

From time to time, we enter into other strategic agreements such as divestitures and financing transactions pursuant to which we are required to make representations and warranties and undertake to perform or comply with certain covenants. For example, we made certain intellectual property representations in connection with our RPI and HCR transactions, however, the time limitation we have to indemnify RPI with respect to any breach of these intellectual property-based representations and warranties has passed. In the event it is determined that we breached certain of the representations and warranties or covenants made by us in any such agreements or certain express indemnification provisions are applicable, we could incur substantial indemnification liabilities depending on the timing, nature, and amount of any such claims.

To date, we have not incurred any costs to defend lawsuits or settle claims related to these indemnification obligations, nor any breaches of representations or warranties or covenants. Because the aggregate amount of any potential indemnification obligation is not a stated amount, we cannot reasonably estimate the overall maximum amount of any such obligations.

Indemnification of Underwriters and Initial Purchasers of our Securities

In connection with our sale of equity we have agreed to defend, indemnify and hold harmless our underwriters or initial purchasers, as applicable, as well as certain related parties from and against certain liabilities, including liabilities under the Securities Act of 1933, as amended.

Director and Officer Indemnifications

As permitted under Delaware law, and as set forth in our Certificate of Incorporation and our Bylaws, we indemnify our directors, executive officers, other officers, employees, and other agents for certain events or occurrences that may arise while in such capacity. The maximum potential amount of future payments we could be required to make under this indemnification is unlimited; however, we have insurance policies that may limit our exposure and may enable us to recover a portion of any future amounts paid. Assuming the applicability of coverage, the willingness of the insurer to assume coverage, and subject to certain retention, loss limits and other policy provisions, we believe any obligations under this indemnification would not be material, other than retention of up to $2.5 million per incident for merger and acquisition related claims, $2.5 million per incident for securities related claims and $2.5 million per incident for non-securities related claims per our insurance policy. However, no assurances can be given that the covering insurers will not attempt to dispute the validity, applicability, or amount of coverage without expensive litigation against these insurers, in which case we may incur substantial liabilities as a result of these indemnification obligations.

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Note 8 — Stockholders’ Equity

On June 6, 2025, we filed a Certificate of Amendment to the Certificate of Incorporation, or the Increase in Shares Amendment, to increase the number of authorized shares of the Company’s common stock from 300,000,000 shares to 390,000,000 shares. The increase in authorized shares amendment was previously approved by our stockholders at the Annual Meeting of Stockholders held on May 23, 2025 and became effective upon its filing.

On June 6, 2025, we also filed a Certificate of Amendment to Nektar’s Certificate of Incorporation (the Reverse Stock Split Amendment) to effect a reverse stock split of our common stock at a ratio of one-for-fifteen (the Reverse Stock Split). The Reverse Stock Split Amendment became effective as of 11:59 p.m. Eastern Time on June 8, 2025 (the Effective Time), at which time every fifteen shares of our common stock issued and outstanding immediately prior to the Effective Time were combined into one share of common stock. No fractional shares of our common stock were issued as a result of the Reverse Stock Split. Instead, any fractional shares resulting from the Reverse Stock Split were rounded up at the participant level if such shares of our common stock (including shares subject to issuance upon exercise of the pre-funded warrant) were held directly or rounded down to the nearest whole share of our common stock, if such shares were subject to an award granted under the 2017 Amended and Restated Performance Incentive Plan. Upon effectiveness of the Reverse Stock Split, the number of shares of common stock for which each outstanding option and pre-funded warrant to purchase common stock is exercisable was adjusted, and the exercise price of each outstanding option and pre-funded warrant to purchase common stock was adjusted. The Reverse Stock Split did not change the par value per share or the authorized number of shares of common stock and preferred stock. As a result of the Reverse Stock Split, we have retrospectively recast prior periods for shares of our common stock, including those issued, outstanding and treasury stock, weighted-average shares outstanding and loss per share.

TCG Pre-Funded Warrant

In March 2024, we issued a pre-funded warrant to purchase an aggregate of 1,666,667 shares of our common stock to TCG Crossover Fund II, L.P. (TCG) at a price of $18.00 per share for gross proceeds of $30.0 million. Transaction costs were immaterial. The TCG Pre-funded Warrant had an exercise price of $0.0015 per share and was exercisable at any time after the original issuance date. TCG could not exercise the warrant if TCG, together with its affiliates, would beneficially own more than 9.99% of the number of shares of our common stock outstanding immediately after giving effect to such exercise. TCG could increase or decrease this percentage not in excess of 19.99% by providing at least 61 days prior notice to the Company. On May 28, 2024, we filed with the SEC a registration statement on Form S-3 (file no. 333-279760) registering for resale of up to 1,666,667 shares of our common stock issuable upon exercise of the TCG Pre-funded Warrant. The registration statement became effective on June 5, 2024.

We classified the TCG Pre-funded Warrant as a component of permanent equity in our Consolidated Balance Sheets as it is a freestanding financial instrument that was immediately exercisable, does not embody an obligation for the Company to repurchase its own shares and permits the holder to receive a fixed number of shares of common stock upon exercise. All of the shares underlying the TCG Pre-funded Warrant have been included in the weighted-average number of shares of common stock used to calculate net loss per share attributable to common stockholders because the shares may be issued for little or no consideration, are fully vested and are exercisable after the original issuance date of the TCG Pre-funded Warrant.

On July 1, and July 11, 2025, TCG exercised the TCG Pre-funded Warrant to purchase 780,000 and 886,667 shares of common stock, respectively. Exercise proceeds are immaterial. As a result of these exercises, no shares remain issuable under the warrant.

Secondary Offerings

On July 2, 2025, pursuant to the April 2025 Shelf Registration Statement, we completed the sale and issuance of 4,893,618 shares of our common stock in an underwritten public offering (the 2025 Offering) at a price of $23.50 per share, which included 638,298 shares sold upon exercise in full by the underwriters of their option to purchase additional shares of common stock in the 2025 Offering. The net proceeds to the Company from the 2025 Offering totaled approximately $107.2 million, after deducting underwriting discounts and commissions and other offering costs.

In connection with the 2025 Offering, we re-issued all 552,307 shares held in treasury stock as of June 30, 2025.

On February 13, 2026, pursuant to the November 2025 Shelf Registration Statement, we completed the sale and issuance of 7,637,931 shares of common stock at a price of $58.00 per share, which included 1,034,482 shares sold upon exercise in full by the underwriters of their option to purchase additional shares of common stock in the 2026 Offering, and 293,103 pre-funded warrants at price of $57.9999 per pre-funded warrant in an underwritten public offering. The estimated net proceeds from the 2026 Offering totaled approximately $432.0 million, after deducting underwriting discounts and

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commissions and estimated offering expenses of approximately $28.0 million. Each pre-funded warrant has an exercise price of $0.0001 per share.

At-The-Market Offerings

In September and October 2025, we issued 1,273,923 shares of our common stock under the April 2025 ATM Sales Agreement at a weighted average price of $58.87 per share for net proceeds of $72.5 million after deducting related commissions and offering costs. No shares remain available for issuance under the April 2025 ATM Sales Agreement.

On November 12, 2025, we also entered into the November 2025 ATM Sales Agreement with Piper Sandler & Co. and BTIG, LLC, relating to the sale of our common stock having an aggregate offering price of up to $110.0 million in an “at-the-market” offering. As of December 31, 2025, no shares were issued under the November 2025 ATM Sales Agreement. From February 20, 2026 through March 11, 2026, we issued 639,131 shares of our common stock under the November 2025 ATM Sales Agreement at a weighted average price of $71.15 per share for net proceeds of $44.1 million after deducting related commissions of approximately $1.4 million.

Shares Reserve for Issuance

Shares of common stock reserved for future issuance are as follows:

December 31,

Shares reserved for TCG Pre-funded Warrant — 1,666,667

Shares available for future grant under the 2025 Inducement Plan 231,690 —

Note 9 — License and Collaboration Agreements

We have entered into various collaboration agreements including license agreements and collaborative research, development and commercialization agreements with various pharmaceutical and biotechnology companies. Under these collaboration arrangements, we are entitled to receive license fees, upfront payments, milestone and other contingent payments, royalties, sales milestone payments, reimbursements for research and development activities and (before the sale of the Facility) payments for the manufacture and supply of our PEG reagents. We generally include our costs of performing these services in research and development expense, except for costs for product sales to our collaboration partners which we include in cost of goods sold. We analyze our agreements to determine whether we should account for the agreements within the scope of ASC 808 Collaborative Arrangements, and, if so, we analyze whether we should account for any elements under ASC 606 Revenue from Contracts with Customers.

Biolojic Design, Ltd. (Biolojic): NKTR-0165

In 2021, we entered into a research collaboration and license option agreement with Biolojic to discover and develop agonistic antibodies that activate a novel and previously un-drugged target for the treatment of autoimmune diseases. In 2023, we exercised an option to gain an exclusive license to specified agonistic antibodies and other materials that were developed pursuant to this arrangement in all fields of use (other than in the field of oncology). As a result of exercising the option to gain an exclusive license, we may be required to pay up to $18.0 million based on the achievement of certain development milestones, including the first milestone of $3.0 million payable upon the acceptance of the first investigational new drug application, and up to $35.0 million based on the achievement of certain regulatory approval milestones. Each milestone is payable only once, regardless of the number of indications for which we develop the licensed product. We record a liability when a milestone payment becomes probable. As of December 31, 2025, no milestones have been achieved or are considered probable, and no liability has been recorded.

Bristol-Myers Squibb Company (BMS): Bempegaldesleukin, also referred to as NKTR-214

Effective April 3, 2018, we entered into a Strategic Collaboration Agreement (the BMS Collaboration Agreement) and a Share Purchase Agreement with BMS. Pursuant to the BMS Collaboration Agreement, we and BMS jointly developed bempegaldesleukin in combination with BMS’ Opdivo®. Upon the effective date of these agreements, BMS paid us a non-refundable upfront cash payment of $1.0 billion and purchased 552,307 shares of our common stock for total additional cash consideration of $850.0 million.

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In April 2022, we announced that BMS and we decided to discontinue all development of bempegaldesleukin in combination with Opdivo®. On September 6, 2023, BMS and we terminated the BMS Collaboration Agreement. On February 12, 2024, we repurchased the 552,307 shares previously sold to BMS for total cash consideration of $3.0 million.

Other

We have other collaboration agreements that have resulted in commercialized products for our collaborations partners. Under these agreements, we are entitled to receive royalties based on net sales of these products as well as sales milestones. As discussed in Note 6, we have sold our rights to receive royalties from these other collaboration agreements.

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NKTR · 10-K · period ended 2025-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

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NKTR · 10-K · period ended 2025-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

NKTR US Equity