INO US Equity☆

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

This report contains forward-looking statements, as defined in Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. These statements relate to future events or our future financial performance. In some cases, you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “potential” or “continue,” the negative of such terms or other comparable terminology. These statements are only predictions. Actual events or results may differ materially.

Although we believe that the expectations reflected in the forward-looking statements are reasonable based on our current expectations and projections, we cannot guarantee future results, levels of activity, performance or achievements. Moreover, neither we, nor any other person, assume responsibility for the accuracy and completeness of the forward-looking statements. We are under no obligation to update any of the forward-looking statements after the filing of this Annual Report to conform such statements to actual results or to changes in our expectations.

The following discussion of our financial condition and results of operations should be read in conjunction with our consolidated financial statements and the related notes and other financial information appearing elsewhere in this Annual Report. Readers are also urged to carefully review and consider the various disclosures made by us which attempt to advise interested parties of the factors which affect our business, including without limitation the disclosures made in Item 1A of Part I of this Annual Report under the caption “Risk Factors.”

Risk factors that could cause actual results to differ from those contained in the forward-looking statements include but are not limited to: our history of losses; our lack of products that have received regulatory approval; uncertainties inherent in clinical trials and product development programs, including but not limited to the fact that pre-clinical and clinical results may not be indicative of results achievable in other trials or for other indications, that the studies or trials may not be successful or achieve desired results, that preclinical studies and clinical trials may not commence, have sufficient enrollment or be completed in the time periods anticipated, that results from one study may not necessarily be reflected or supported by the results of other similar studies, that results from an animal study may not be indicative of results achievable in human studies, that clinical testing is expensive and can take many years to complete, that the outcome of any clinical trial is uncertain and failure can occur at any time during the clinical trial process, and that our proprietary smart device technology and DNA medicine candidates may fail to show the desired safety and efficacy traits in clinical trials; the availability of funding; the ability to manufacture our DNA medicine candidates; the availability or potential availability of alternative therapies or treatments for the conditions targeted by us or our collaborators, including alternatives that may be more efficacious or cost-effective than any therapy or treatment that we and our collaborators hope to develop; our ability to receive development, regulatory and commercialization event-based payments under our collaborative agreements; whether our proprietary rights are enforceable or defensible or infringe or allegedly infringe on rights of others or can withstand claims of invalidity; and the impact of government healthcare laws and proposals.

Overview

We are a biotechnology company focused on developing and commercializing DNA medicines to help treat and protect people from diseases associated with HPV, cancer, and infectious diseases. Our goal is to advance our diverse pipeline of product candidates and deliver on the promise of DNA medicines technology in treating and preventing a wide array of diseases.

In clinical trials, our DNA medicine candidates have shown the ability to generate immune responses, especially CD4+, CD8+, and memory T-cell responses against targeted pathogens and cancers, via our precisely designed plasmids. These plasmids are delivered into cells using our investigational proprietary smart device, CELLECTRA.

Many of our lead candidates are focused on diseases associated with HPV. In 2022, we announced data from a Phase 1/2 clinical trial with INO-3107 for the treatment of HPV-6 and HPV-11 associated RRP. In this trial, treatment with INO-3107 resulted in a statistically significant reduction of the median number of surgeries, a result that reinforces our belief that DNA medicines may play a key role in the treatment of HPV-related diseases.

Our partners and collaborators include Advaccine Biopharmaceuticals Suzhou Co, ApolloBio Corporation, AstraZeneca, The Bill & Melinda Gates Foundation (Gates), Coalition for Epidemic Preparedness Innovations (CEPI), Defense Advanced Research Projects Agency (DARPA), The U.S. Department of Defense (DoD), HIV Vaccines Trial Network, International Vaccine Institute (IVI), Kaneka Eurogentec, National Cancer Institute (NCI), National Institutes of Health (NIH), National Institute of Allergy and Infectious Diseases (NIAID), the Parker Institute for Cancer Immunotherapy, Plumbline Life Sciences, Regeneron Pharmaceuticals, Richter-Helm BioLogics, Thermo Fisher Scientific, the University of Pennsylvania, the Walter Reed Army Institute of Research, and The Wistar Institute.

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We or our collaborators are currently evaluating the feasibility of, or conducting or planning clinical studies of, our DNA medicines for Ebola HPV-related precancers, including cervical, vulvar, and anal dysplasia; HPV-related cancers, including head & neck, cervical, anal, penile, vulvar, and vaginal; other HPV-related disorders, such as RRP; and GBM.

All of our DNA medicine candidates are in the research and development phase. We have not generated any revenues from the sale of any products, and we do not expect to generate any such revenues for at least the next several years. We earn revenue from license fees and milestone revenue and collaborative research and development agreements and contracts. Our DNA medicine candidates will require significant additional research and development efforts, including extensive preclinical and clinical testing. All DNA medicine candidates that we advance to clinical testing will require regulatory approval prior to commercial use, and will require significant costs for commercialization. We may not be successful in our research and development efforts, and we may never generate sufficient product revenue to be profitable.

As of December 31, 2022, we had an accumulated deficit of $1.5 billion. We expect to continue to incur substantial operating losses in the future due to our commitment to our research and development programs, the funding of preclinical studies, clinical trials and regulatory activities and the costs of general and administrative activities.

VGX-3100 Update

REVEAL2 is our second Phase 3 trial with VGX-3100. In April 2022, the trial protocol was amended to utilize a biomarker-selected population as the primary population, based on prior analysis of REVEAL1 results suggesting that this investigational biomarker had the potential to identify women more likely to respond to treatment with VGX-3100. We announced that this trial would no longer be considered to be a pivotal trial and would not lead to a BLA filing for a biomarker-selected population, as the FDA advised us that the biomarker-positive population would not be sufficient to support approval of a potential marketing application for VGX-3100. The FDA recommended using REVEAL2 as an exploratory trial and that conducting one or two additional well-controlled trials in the biomarker-selected population would be more likely to provide evidence to support approval of a marketing application.

Trial participants in REVEAL2 included 203 women, 18 years of age or older, who had histologically-confirmed cervical HSIL associated with HPV-16 and/or HPV-18, but who were otherwise healthy. Participants received either VGX-3100 or placebo at 0, 4 and 12 weeks (randomized 2:1). The primary endpoint, as amended, was the percentage of biomarker-selected participants with regression of cervical HSIL and virologic clearance of HPV-16 and/or HPV-18 in the cervix. A secondary endpoint was the percentage of all participants with regression and virologic clearance.

In March 2023, we announced data from our REVEAL2 trial. Statistical significance was not achieved in the investigational biomarker-selected population for the endpoint of lesion regression and viral clearance. However, statistical significance was achieved in the all-participants population for the endpoint of lesion regression and viral clearance.

The percentage of participants in the investigational biomarker-selected population meeting the primary endpoint was 28.6% (6/21) in the treatment group, versus 0% (0/4) in the placebo group (p=0.115; difference in percentage 28.6, 95%CI: -24.6, 50.4), which was not statistically significant.

The result of the all-participants population of 203 participants (134 participants in the treatment group, 69 in the placebo group) was statistically significant, with 27.6% (37/134) of the participants meeting the endpoint in the treatment group, versus 8.7% (6/69) in the placebo group (p=0.001; difference in percentage 18.9, 95%CI: 7.8, 28.6).

In particular, in the all-participants population of REVEAL2, viral clearance was observed in 37.3% (50/134) in the treatment group versus 8.7% (6/69) in the placebo group. Given the importance of viral clearance in removing the underlying cause of the HPV-related diseases, this data may have positive implications in our other HPV-related programs.

An ad-hoc integrated efficacy analysis of the results for both REVEAL1 and REVEAL2 achieved statistical significance in the biomarker-selected and all-participants populations for lesion regression and viral clearance. For the combined biomarker-selected population of 92 participants (68 participants in the treatment group, 24 in the placebo group), the percentage of participants meeting the primary endpoint was 54.4% (37/68 in the treatment group, versus 12.5% (3/24) in the placebo group (p=<0.001; difference in percentage 41.9, 95%CI: 20.4, 57.0). For the combined all-participants population of 404 participants (272 participants in the treatment group, 132 in the placebo group), the percentage of participants meeting the primary endpoint was 25.0% (68/272 in the treatment group, versus 9.8% (13/132) in the placebo group (p=<0.001; difference in percentage 15.2, 95%CI: 7.4, 22.1).

In both REVEAL1 and REVEAL2, VGX-3100 was well-tolerated. There were no treatment-related serious adverse events and most adverse events were considered to be mild to moderate.

This combined data set will be used as supportive data in future regulatory interactions involving VGX-3100. We will continue to evaluate the results to determine next steps for VGX-3100 in our HPV programs. We plan to submit the data for publication in a peer-reviewed journal later this year.

INO-4800 Update

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On October 27, 2022, we announced that we have discontinued our internally funded efforts to develop INO-4800 as a COVID-19 heterologous booster vaccine. The decision was based on our assessment of the current global demand for COVID-19 vaccines, changes in regulatory timelines and requirements, diminishing government financial support, and the overall growing uncertainty related to opportunities for heterologous booster vaccines.

INO-4800 continues to be evaluated as part of the World Health Organization’s Solidarity Trial Vaccines and we continue preclinical development of a potential pan-COVID-19 vaccine candidate. In addition, our clinical collaborator Advaccine is continuing to develop INO-4800 as a potential COVID-19 heterologous booster vaccine in Greater China using its own resources.

Reductions in Force

On January 31, 2023, we committed to and communicated a corporate reorganization plan, including a reduction in force, or the Reduction. The purpose of the Reduction was to decrease expenses and maintain a streamlined organization to support key clinical programs that are expected to drive long-term growth. As part of the Reduction, we reduced overall headcount by approximately 24 employees, which represented 11% of our full-time employees. Along with other planned cost-saving measures, the Reduction is expected to provide annual savings of approximately $4.3 million. We expect to incur a one-time pre-tax charge of approximately $1.1 million in the first quarter of 2023 related to the Reduction, consisting primarily of one-time severance payments upon termination, continued benefits for a specific period of time, and outplacement services.

In the third quarter of 2022, we undertook a separate reorganization and reduced overall headcount by approximately 55 employees, which represented 18% of our full-time employees. We also terminated agreements with approximately 86% of our contractors. We incurred a one-time pre-tax charge of $1.6 million in the third quarter of 2022 related to these actions, consisting primarily of one-time severance payments upon termination, continued benefits and outplacement services.

Securities Class Action Settlement

In January 2023, the United States District Court for the Eastern District of Pennsylvania, or the Court, entered an order, or the Order, granting final approval for the settlement of the class action securities litigation described in this report under “Legal Proceedings.”The settlement includes $30.0 million in cash and $14.0 million in shares of our common stock to settle all outstanding claims. Our insurance carriers have paid the cash component of the settlement and we will therefore not incur any material cash expenses associated with the litigation, other than legal fees and related expenses, which were approximately $11.0 million through December 31, 2022.

In February 2023, pursuant to the securities class action settlement, we issued 7,000,000 shares of common stock. Following the expiration of the appeal period or resolution of an appeal if one is filed, we will make another contribution of common stock to the settlement fund with a value of approximately $2.1 million.

Critical Accounting Policies and Estimates

The SEC defines critical accounting policies as those that are, in management’s view, important to the portrayal of our financial condition and results of operations and require management’s judgment. Our discussion and analysis of our financial condition and results of operations are based on our audited consolidated financial statements, which have been prepared in accordance with U.S. GAAP. Our significant accounting policies are outlined in Note 2 to the consolidated financial statements included in this report.

The preparation of these consolidated financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenue and expenses. We base our estimates on experience and on various assumptions that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from those estimates. We believe the following accounting policies to be critical to the judgments and estimates used in the preparation of our consolidated financial statements:

Collaboration Agreements and Revenue Recognition

We assess whether our collaboration agreements are subject to Accounting Standards Codification ("ASC") Topic 808: Collaborative Arrangements (“Topic 808”) based on whether they involve joint operating activities and whether both parties have active participation in the arrangement and are exposed to significant risks and rewards. To the extent that the arrangement falls within the scope of Topic 808 and we conclude that our collaboration partner is not a customer, we present such payments as a reduction of research and development expense. If payments from our collaboration partner to us represent consideration from a customer, then we account for those payments within the scope of Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (“Topic 606”).

We enter into collaborative arrangements with partners that typically include payment of one or more of the following: (i) license fees; (ii) product supply services; (iii) milestone payments related to the achievement of developmental, regulatory, or

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commercial goals; and (iv) royalties on net sales of licensed products. At contract inception, we assess the goods or services agreed upon within each contract and assess whether each good or service is distinct and determine those that are performance obligations. We then recognize as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

As part of the accounting for these arrangements, we must develop estimates and assumptions that require judgment of management to determine the underlying stand-alone selling price for each performance obligation which determines how the transaction price is allocated among the performance obligation. The standalone selling price may include items such as forecasted revenues, development timelines, discount rates and probabilities of technical and regulatory success. We evaluate each performance obligation to determine if it can be satisfied at a point in time or over time. In addition, variable consideration must be evaluated to determine if it is constrained and, therefore, excluded from the transaction price. Differences in the allocation of the transaction price between delivered and undelivered performance obligations can impact the timing of revenue recognition but do not change the total revenue recognized under any agreement.

For collaboration arrangements that include license fees, we recognize revenues from non-refundable, upfront fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, we utilize judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. We evaluate the measure of progress each reporting period and, if necessary, adjust the measure of performance and related revenue recognition.

For collaboration arrangements that include milestone payments (variable consideration), we evaluate whether the milestones are considered probable of being reached and estimate the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. This assessment is based on our past experience with our collaboration partner, market insight and partner communication. Milestone payments that are not within our or our collaboration partner’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. At the end of each subsequent reporting period, we re-evaluate the probability of achieving such milestones and any related constraint, and if necessary, adjust our estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration or other revenues and earnings in the period of adjustment and could be material.

For collaboration arrangements that include sales-based royalties, including milestone payments based on the level of sales, and for which the license is deemed to be the predominant item to which the royalties relate, we recognize revenue in the period the underlying sales occur. To date, we have not recognized any royalty revenue resulting from any of our collaborative arrangements.

Research and Development Expenses - Clinical Trial Accruals

Our activities have largely consisted of research and development efforts related to developing proprietary smart device technologies, DNA medicine candidates and dMABs. For clinical trial expenses, judgments used in estimating accruals rely on estimates of total costs incurred based on participant enrollment, completion of studies and other events. Accrued clinical trial costs are subject to revisions as trials progress. Revisions are charged to expense in the period in which the facts that give rise to the revision become known. Historically, revisions have not resulted in material changes to research and development expense; however a modification in the protocol of a clinical trial or cancellation of a trial could result in a charge to our results of operations.

Recent Accounting Pronouncements

Information regarding recent accounting pronouncements is contained in Note 2 to the consolidated financial statements, included elsewhere in this report.

Results of Operations

The consolidated financial data for the years ended December 31, 2022, 2021 and 2020 is presented in the following table and the results of these periods are used in the discussion thereafter.

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Operating expenses:

Loss on extinguishment of convertible bonds — — (8,177,043) — * 8,177,043 *

*Not meaningful

Comparison of Years Ended December 31, 2022 and 2021

Revenue

Revenue was primarily derived under collaborative arrangements and contracts, including arrangements with affiliated entities, for the years ended December 31, 2022 and 2021. The $8.5 million increase in revenue was primarily due to higher revenue earned from our Procurement Contract with the DoD.

Research and Development Expenses

Research and development expenses consist of expenses incurred in performing research and development activities, including compensation and benefits for full-time research and development employees, facilities expenses, overhead expenses, cost of laboratory supplies, clinical trial and related clinical manufacturing expenses, fees paid to contract research organizations and other consultants, and outside expenses. We utilize a labor reporting system to record employee compensation on a project-by-project basis. Unallocated research and development expenses include engineering and device-related expenses that are not allocable to a specific project, as well as stock-based compensation, other employee-related expenses that are not related to a specific project, and facilities and depreciation expenses.

Research and development costs are expensed as incurred. Non-refundable advance payments for goods or services to be received in the future for use in research and development activities are deferred and capitalized. The capitalized amounts are expensed as the related goods are delivered or the services are performed.

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The following tables summarize our research and development expense by product candidate for the years ended December 31, 2022 and 2021:

Years Ended December 31, Increase (Decrease)

The $61.6 million overall decrease in research and development expenses year over year was primarily the result of:

•$45.9 million in lower drug manufacturing and outside services related to INO-4800;

•$21.9 million of costs related to the acquisition and installation of manufacturing equipment for INO-4800 during 2021 that did not recur in 2022;

•$15.6 million in lower engineering services and expensed equipment related to our CELLECTRA 3PSP device and array automation project;

•$11.8 million in lower clinical study, outside services and immunology expenses related to VGX-3100;

•$4.9 million in lower expensed inventory related to the CELLECTRA 2000 device; and

•$4.6 million in lower employee stock-based compensation primarily from lower weighted average grant date fair values for the awards granted during 2022.

These decreases were partially offset by:

•$29.2 million of lower contra-research and development expense recorded from grant agreements; and

•$14.4 million of increased drug manufacturing costs related to our COVID-19 variant studies and DARPA COVID-19 dMAb grant.

Contributions received from current grant agreements and recorded as contra-research and development expense were $24.5 million and $53.7 million for the years ended December 31, 2022 and 2021, respectively. The decrease year over year was primarily due to decreases of $21.0 million, $5.8 million, $3.3 million and $3.2 million earned under the DoD 3PSP device development grant, CEPI grants related to INO-4800 and device development activities, reimbursements from Advaccine and the CEPI Lassa and MERS grant, respectively. These decreases were offset by an increase of $5.3 million, earned primarily under the sub-grant through Wistar for DARPA COVID-19 dMAb.

General and Administrative Expenses

General and administrative expenses, which include business development expenses, the amortization of intangible assets and patent expenses, were $90.2 million for the year ended December 31, 2022 as compared to $53.8 million in 2021. The $36.4 overall increase year over year was primarily the result of:

•$44.0 million related to the class action securities litigation settlement, which was reduced by $30.0 million of insurance recoveries, resulting in a net $14.0 million expense, which is the value of our common stock to be issued in connection with the settlement;

•$14.3 million in higher legal expenses, primarily related to litigation matters;

•$6.9 million in severance expenses related to the separation of our former President and Chief Executive Officer in May 2022, including $4.2 million of stock-based compensation expense related to equity award modifications (see Note 10 to our consolidated financial statements included in this report for additional information); and

•$1.6 million in overall higher employee compensation.

Employee stock-based compensation cost is measured at the grant date, based on the fair value of the award, and is recognized as expense over the employee’s requisite service period. Total employee stock-based compensation cost for the

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years ended December 31, 2022 and 2021 was $22.2 million and $25.0 million, of which $8.8 million and $13.4 million was included in research and development expenses and $13.4 million and $11.6 million was included in general and administrative expenses, respectively.

Interest Income

The $1.4 million increase in interest income for the year ended December 31, 2022 as compared to 2021 was primarily due to higher interest rates.

Interest Expense

The $682,000 decrease in interest expense for the year ended December 31, 2022 as compared to 2021 was primarily due to lower non-cash interest expense related to the $78.5 million aggregate principal amount of our 6.50% convertible senior notes due 2024 as a result of the adoption of ASU‐2020-06, and no interest expense recorded on the convertible promissory notes issued in December 2019 due to their full conversion into shares of our common stock in March 2021.

Loss on Investment in Affiliated Entity

The loss on investment in affiliated entity resulted from the declines in the fair market value of our investment in PLS of $1.9 million and $554,000 for the years ended December 31, 2022 and 2021, respectively. We record our investment in PLS at its market value based on the closing price of the shares on the Korea New Exchange Market at each balance sheet date, with changes in fair value reflected in the consolidated statements of operations.

Net Unrealized Loss on Available-for-Sale Equity Securities

The net unrealized loss on available-for-sale equity securities for the years ended December 31, 2022 and 2021 was $7.8 million and $3.2 million, respectively, which resulted from a change in the fair market value of the investments.

Share in Net Loss of Geneos

The share in net loss of Geneos represents our share of Geneos' losses during the period after deconsolidation in June 2020.

Income Taxes

Since inception, we have incurred operating losses and accordingly have not recorded a provision for U.S. income taxes for any of the periods presented. Utilization of net operating losses and tax credits are subject to a substantial annual limitation due to ownership change limitations provided by the Internal Revenue Code of 1986, as amended, or IRC. As of December 31, 2022, we had net operating loss carry forwards for U.S. federal, California and Pennsylvania income tax purposes of $920.6 million, $210.3 million and $89.6 million, respectively, net of the net operating losses that will expire due to IRC Section 382 limitations. We also had U.S. federal and state research and development tax credits of $40.5 million and $4.7 million, respectively, net of the federal research and development credits that will expire due to IRC Section 383 limitations. The net operating losses and credits began to expire during 2022.

Comparison of Years Ended December 31, 2021 and 2020

For a comparison of the years ended December 31, 2021 and 2020, you may refer to Part II, Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC on March 1, 2022.

Liquidity and Capital Resources

Historically, our primary uses of cash have been to finance research and development activities including clinical trial activities for the advancement of DNA medicine candidates. Since inception, we have satisfied our cash requirements principally from proceeds from the sale of equity securities, indebtedness and grants and government contracts.

Working Capital and Liquidity

As of December 31, 2022, we had cash and short-term investments of $253.0 million and working capital of $218.4 million, as compared to $401.3 million and $382.7 million as of December 31, 2021, respectively.

Cash Flows

Operating Activities

Net cash used in operating activities was $216.2 million and $215.7 million for the years ended December 31, 2022 and 2021, respectively. The variance was primarily due to the timing and changes in working capital balances, offset by decreased operating expenses.

Investing Activities

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Net cash provided by (used in) investing activities was $109.6 million and $(175.3) million for the years ended December 31, 2022 and 2021, respectively. The variance was primarily the result of timing differences in short-term investment purchases, sales and maturities.

Financing Activities

Net cash provided by financing activities was $81.8 million and $211.5 million for the years ended December 31, 2022 and 2021, respectively. The variance was primarily due to the proceeds from the January 2021 underwritten public offering, partially offset by an increase in the proceeds from the sale of common stock under the Sales Agreement (defined below) in 2022 compared to 2021.

Issuances of Common Stock

On November 9, 2021, we entered into an ATM Equity OfferingSM Sales Agreement (the “Sales Agreement”) with outside sales agents (collectively, the “Sales Agents”) under which we may offer and sell, from time to time at our sole discretion, shares of our common stock with aggregate gross proceeds of up to $300.0 million, through the Sales Agents.

Subject to the terms and conditions of the Sales Agreement, the Sales Agents may sell the common stock by any method permitted by law deemed to be an “at the market offering”. The Sales Agents will use commercially reasonable efforts to sell the common stock from time to time, based upon instructions from us, including any price, time or size limits or other customary parameters or conditions we may impose. We will pay the Sales Agents a commission of up to three percent (3.0%) of the gross sales proceeds of any common stock sold through the Sales Agents under the Sales Agreement, and we have provided the Sales Agents with certain indemnification rights. During the year ended December 31, 2022, we sold 34,445,743 shares of common stock under the Sales Agreement for aggregate net proceeds of $83.0 million. During the year ended December 31, 2021, we sold 6,955,341 shares of common stock under the Sales Agreement for aggregate net proceeds of $47.7 million.

During the year ended December 31, 2020, we sold 66,064,887 shares of common stock for aggregate net proceeds of $454.5 million under previous ATM sales agreements.

On January 25, 2021, we closed an underwritten public offering of 20,355,000 shares of our common stock at a public offering price of $8.50 per share. The net proceeds, after deducting the underwriters' discounts and commissions and other estimated offering expenses payable by us, were $162.1 million.

During the year ended December 31, 2022, stock options to purchase 118,694 shares of common stock were exercised for aggregate net proceeds of $283,000, which proceeds were offset by tax payments made related to net share settlement of RSU awards of $1.4 million. During the year ended December 31, 2021, stock options to purchase 1,310,263 shares of common stock were exercised for aggregate net proceeds of $6.7 million, which proceeds were offset by tax payments made related to net share settlement of RSU awards of $4.6 million. During the year ended December 31, 2020, stock options to purchase 2,178,252 shares of common stock were exercised for aggregate net proceeds of $12.3 million, which proceeds were offset by tax payments made related to net share settlement of RSU awards of $4.0 million.

FundingRequirements

As of December 31, 2022, we had an accumulated deficit of $1.5 billion and we expect to continue to operate at a loss for some time. The amount of the accumulated deficit will continue to increase, as it will be expensive to continue research and development efforts. Our current cash resources, including amounts that we may be able to obtain through sales of common stock under our “at the market” equity facility, will not be sufficient to complete the clinical development of any of our product candidates, and we anticipate that additional financing will be required in order to commercialize and generate revenues from the sale of any product candidates that receive regulatory approval. If these activities are successful and if we receive approval from the FDA to market our DNA medicine candidates, then we will need to raise additional funding to market and sell the approved products and equipment. In addition to the potential issuance of equity or debt securities in order to raise capital, we are also evaluating potential collaborations as an additional way to fund our operations. We believe that our current cash and short-term investments are sufficient to meet our planned working capital requirements for at least the next twelve months from the date of this report.

As described above, in January 2023 and July 2022, we undertook corporate reorganization plans to decrease our expenses, extend our cash runway, and maintain a streamlined organization to support key clinical programs that we expect to drive our long-term growth. Also, in October 2022, we announced that we have discontinued our internally funded efforts to develop INO-4800 as a COVID-19 heterologous booster vaccine. We expect these actions to reduce our operating expenses incrementally and extend our cash runway into the first quarter of 2025, without giving effect to any further capital raising activities, whether under the Sales Agreement or otherwise.

Contractual Obligations

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As of December 31, 2022, future minimum payments due under our contractual obligations are set forth in the table below. We expect to be able to satisfy these obligations, both in the short-term and in the longer-term, with cash on hand and proceeds from sales of our common stock under the Sales Agreement.

Payments Due by Period

Total Less than1 year 1 – 3 years 3 – 5 years More than5 years

(1) Amounts represent remaining contractual amounts due under our Notes, including interest based on the fixed rate of 6.5% per year. Although these Notes mature in March 2024, they may be converted into shares of our common stock prior to maturity if certain conditions are met. We may also redeem the Notes prior to their maturity if certain conditions are met. Any redemption prior to maturity would result in repayments of the principal amounts sooner than the scheduled repayments as indicated in the table. See Note 9, Convertible Debt, to the consolidated financial statements in this report for additional information.

(2) We have entered into operating leases for our facilities, which expire from 2023 to 2029, and operating leases for office equipment, which expire in 2024. In the fourth quarter of 2019, we entered into two subleases for a portion of our Plymouth Meeting corporate headquarters facility with one period through March 31, 2025 and the other month-to-month after December 31, 2022. As of December 31, 2022, we expect to receive aggregate future minimum lease payments totaling $434,000 (non-discounted) over the duration of the sublease agreements, which expected payments are not included in the table above.

(3) Remaining purchase obligations from supply agreements with contract manufacturers.

In the normal course of business, we are a party to a variety of agreements pursuant to which we may be obligated to indemnify the other party. It is not possible to predict the maximum potential amount of future payments under these types of agreements due to the conditional nature of our obligations and the unique facts and circumstances involved in each particular agreement. Historically, payments made by us under these types of agreements have not had a material effect on our business, consolidated results of operations or financial condition.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Interest Rate Risk

Our primary exposure to market risk is interest rate sensitivity, which is affected by changes in the general level of U.S. interest rates. Under our current policies, we do not use interest rate derivative instruments to manage exposure to interest rate changes. We attempt to increase the safety and preservation of our invested principal funds by limiting default risk, market risk and reinvestment risk. We mitigate default risk by investing in short-term investment-grade securities. During the year ended December 31, 2022, there was a pronounced increase in prevailing interest rates in the United States, which contributed to a loss of $7.8 million in the market value of our investment portfolio during the period.

The interest rate on our indebtedness is fixed and not subject to fluctuations in interest rates.

Foreign Currency Risk

We have operated primarily in the United States and most transactions during the year ended December 31, 2022 were made in United States dollars. Accordingly, we have not had any material exposure to foreign currency rate fluctuations, with the exception of certain cash and cash equivalents held in South Korea that are denominated in South Korean Won and the valuation of our equity investment in PLS, which is denominated in South Korean Won and then translated into United States dollars.

Certain transactions are denominated primarily in foreign currencies, including South Korean Won, Euros, British Pounds and Canadian Dollars. These transactions give rise to monetary assets and liabilities that are denominated in currencies other than the U.S. dollar. The value of these monetary assets and liabilities are subject to changes in currency exchange rates from the time the transactions are originated until settlement in cash. As a result, our financial results could be affected by factors such as changes in foreign currency exchange rates or weak economic conditions in foreign markets where we conduct business.

We do not use derivative financial instruments for speculative purposes and do not engage in exchange rate hedging or hold or issue foreign exchange contracts for trading purposes.

62

Inflation Risk

Inflation generally affects us by increasing our cost of labor. Although inflation has increased generally in the United States in recent months, we do not believe that inflation has had a material effect on our business, financial condition or results of operations during the year ended December 31, 2022.

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

The information required by this Item 8 is incorporated by reference to our Consolidated Financial Statements and the Report of Independent Registered Public Accounting Firm beginning at page F-1 of this report.

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

None.

ITEM 9A. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

We maintain disclosure controls and procedures, which are designed to ensure that information required to be disclosed in the reports we file or submit under the Securities Exchange Act of 1934, as amended, is recorded, processed, summarized and reported within the time periods specified in the SEC's rules and forms, and that such information is accumulated and communicated to our management, including our Chief Executive Officer, or CEO, and Chief Financial Officer, or CFO, as appropriate to allow timely decisions regarding required disclosures.

In designing and evaluating our disclosure controls and procedures, management recognizes that disclosure controls and procedures, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the disclosure controls and procedures are met. Additionally, in designing disclosure controls and procedures, our management necessarily was required to apply its judgment in evaluating the cost-benefit relationship of possible disclosure controls and procedures. The design of any system of controls also is based in part upon certain assumptions about the likelihood of future events, and there can be no assurance that any design will succeed in achieving its stated goals under all potential future conditions; over time, controls may become inadequate because of changes in conditions, or the degree of compliance with policies or procedures may deteriorate. Because of the inherent limitations in a control system, misstatements due to error or fraud may occur and not be detected.

Based on an evaluation carried out as of the end of the period covered by this Annual Report, under the supervision and with the participation of our management, including our CEO and CFO, our CEO and CFO have concluded that, as of the end of such period, our disclosure controls and procedures (as defined in Rule 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934) were effective as of December 31, 2022 at the reasonable assurance level.

Internal Control Over Financial Reporting

Management’s Report on Internal Control Over Financial Reporting and Attestation Report of Registered Public Accounting Firm

Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as defined in Rules 13a-15(f) and 15d-15(f) under the Securities Exchange Act of 1934. Our internal control over financial reporting is a process designed under the supervision of our Chief Executive Officer and Chief Financial Officer to provide reasonable assurance regarding the reliability of financial reporting and the preparation of our financial statements for external purposes in accordance with United States generally accepted accounting principles.

As of December 31, 2022, management, with the participation of the Chief Executive Officer and Chief Financial Officer, assessed the effectiveness of our internal control over financial reporting based on the criteria for effective internal control over financial reporting established in “Internal Control—Integrated Framework,” issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework). Based on the assessment, management determined that we maintained effective internal control over financial reporting as of December 31, 2022.

This Annual Report does not include an attestation report of our registered public accounting firm regarding the effectiveness of internal control over financial reporting as required by Section 404(b) of the Sarbanes-Oxley Act of 2002. Management’s report was not subject to attestation by our registered public accounting firm pursuant to rules of the SEC that permit smaller reporting companies to provide only management’s report in this Annual Report.

Changes in Internal Control over Financial Reporting

63

There have not been any changes in our internal control over financial reporting that occurred during the fourth quarter of our fiscal year ended December 31, 2022, that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

64

ITEM 9B. OTHER INFORMATION

Not applicable.

ITEM 9C. DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

Not applicable.

PART III

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

The information required by this Item 10 is hereby incorporated by reference from our definitive proxy statement, to be filed pursuant to Regulation 14A within 120 days after the end of our 2022 fiscal year, under the captions “Election of Directors” and “Executive Officers and Other Information.”

ITEM 11. EXECUTIVE COMPENSATION

The information required by this Item 11 is hereby incorporated by reference from our definitive proxy statement, to be filed pursuant to Regulation 14A within 120 days after the end of our 2022 fiscal year, under the captions “Compensation Discussion and Analysis,” “Executive Compensation,” “Compensation of Directors” and “Director Compensation Table.”

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

The information required by this Item 12 is hereby incorporated by reference from our definitive proxy statement, to be filed pursuant to Regulation 14A within 120 days after the end of our 2022 fiscal year, under the captions “Security Ownership of Certain Beneficial Owners and Management” and “Equity Compensation Plan Information.”

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE

Director independence and other information required by this Item 13 is hereby incorporated by reference from our definitive proxy statement, to be filed pursuant to Regulation 14A within 120 days after the end of our 2022 fiscal year, under the captions “Certain Relationships and Related Party Transactions” and “Election of Directors.”

ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES

The information required by this Item 14 is hereby incorporated by reference from our definitive proxy statement, to be filed pursuant to Regulation 14A within 120 days after the end of our 2022 fiscal year, under the caption “Ratification of Appointment of Registered Public Accounting Firm.”

65

PART IV

ITEM 15. EXHIBITS, FINANCIAL STATEMENT SCHEDULES

1.Financial Statements

Consolidated financial statements required to be filed hereunder are indexed on Page F-1 hereof.

2.Financial Statement Schedules

Schedules not listed herein have been omitted because the information required to be set forth therein is not applicable or is included in the Financial Statements or notes thereto.

3.Exhibits

The following exhibits are filed as part of this annual report on Form 10-K:

ExhibitNumber Description of Document

66

67

21.1 Subsidiaries of the registrant (filed herewith).

23.1 Consent of Independent Registered Public Accounting Firm (filed herewith).

68

24.1 Power of Attorney (included on signature page).

101.SCH XBRL Taxonomy Extension Schema Document.

101.CAL XBRL Taxonomy Extension Calculation Linkbase Document.

101.DEF XBRL Taxonomy Extension Definition Linkbase Document.

101.LAB XBRL Taxonomy Extension Label Linkbase Document.

101.PRE XBRL Taxonomy Extension Presentation Linkbase Document.

+ Designates management contract, compensatory plan or arrangement.

ITEM 16. FORM 10-K SUMMARY

Not applicable.

69

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized on March 1, 2023.

Inovio Pharmaceuticals, Inc.

By: /s/ JACQUELINE E. SHEA

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Jacqueline E. Shea and Peter Kies, and each of them severally, his or her true and lawful attorney-in-fact with power of substitution and resubstitution to sign in his or her name, place and stead, in any and all capacities, to do any and all things and execute any and all instruments that such attorney may deem necessary or advisable under the Securities Exchange Act of 1934 and any rules, regulations and requirements of the United States Securities and Exchange Commission in connection with the Annual Report on Form 10-K and any and all amendments hereto, as fully for all intents and purposes as he or she might or could do in person, and hereby ratifies and confirms all said attorneys-in-fact and agents, each acting alone, and his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the Registrant and in the capacities and on the dates indicated.

Signature Title Date

Jacqueline E. Shea

/s/ SIMON X. BENITO Chairman of the Board of Directors March 1, 2023

Simon X. Benito

Peter Kies

/s/ ROGER D. DANSEY Director March 1, 2023

Roger D. Dansey

/s/ ANN C. MILLER Director March 1, 2023

Ann C. Miller

/s/ JAY SHEPARD Director March 1, 2023

Jay Shepard

/s/ DAVID B. WEINER Director March 1, 2023

David B. Weiner

/s/ WENDY L. YARNO Director March 1, 2023

Wendy L. Yarno

/s/ LOTA S. ZOTH Director March 1, 2023

Lota S. Zoth

70

INOVIO PHARMACEUTICALS, INC.

Index to Consolidated Financial Statements

Page

Report of Independent Registered Public Accounting Firm (PCAOB ID: 42) F-2

Consolidated Balance Sheets F-4

Consolidated Statements of Operations F-5

Consolidated Statements of Comprehensive Loss F-6

Consolidated Statements of Stockholders' Equity F-7

Consolidated Statements of Cash Flows F-8

Notes to Consolidated Financial Statements F-9

F-1

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Shareholders and the Board of Directors of Inovio Pharmaceuticals, Inc.

Opinion on the Financial Statements

We have audited the consolidated balance sheets of Inovio Pharmaceuticals, Inc. (the “Company”) as of December 31, 2022 and 2021, the related consolidated statements of operations, comprehensive loss, stockholders’ equity, and cash flows for each of the three years in the period ended December 31, 2022, 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 as of December 31, 2022 and 2021, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2022, 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 PCAOB and are required to be independent with respect to the Company in accordance with the US 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. 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 include 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 separate opinions on the critical audit matter or on the accounts or disclosures to which it relates.

F-2

Accrual of Clinical Trial Expenses

/s/ Ernst & Young LLP

We have served as the Company's auditor since 2002.

San Diego, California

F-3

Inovio Pharmaceuticals, Inc.

CONSOLIDATED BALANCE SHEETS

December 31,

ASSETS

Current assets:

LIABILITIES AND STOCKHOLDERS’ EQUITY

Current liabilities:

Grant funding liability from affiliated entities 87,673 37,500

Deferred revenue, net of current portion — 64,361

Other liabilities — 14,826

Commitments and contingencies

Inovio Pharmaceuticals, Inc. stockholders’ equity:

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

F-4

Inovio Pharmaceuticals, Inc.

CONSOLIDATED STATEMENTS OF OPERATIONS

For the Year ended December 31,

Operating expenses:

Other income (expense):

Change in fair value of derivative liability — — (75,670,977)

Gain on deconsolidation of Geneos — — 4,121,075

Loss on extinguishment of convertible bonds — — (8,177,043)

Gain on extinguishment of convertible senior notes — — 8,762,030

Net loss attributable to non-controlling interest — — 1,063,757

Net loss per share attributable to Inovio Pharmaceuticals, Inc. stockholders

Weighted average number of common shares outstanding

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

F-5

Inovio Pharmaceuticals, Inc.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS

For the Year ended December 31,

Other comprehensive (loss) income:

Comprehensive loss attributable to non-controlling interest — — 1,063,757

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

F-6

Inovio Pharmaceuticals, Inc.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY

Numberof shares Amount Numberof shares Amount

Conversion of preferred stock to common stock (14) — 5,147 5 (5) — — — —

Foreign currency translation — — — — — — 27,205 — 27,205

Unrealized gain on short-term investments, net of tax — — — — — — 4,048 — 4,048

Foreign currency translation — — — — — — (30,134) — (30,134)

Foreign currency translation — — — — — — (25,556) — (25,556)

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

F-7

Inovio Pharmaceuticals, Inc.

CONSOLIDATED STATEMENTS OF CASH FLOWS

For the Year ended December 31,

Cash flows from operating activities:

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

Change in fair value of derivative liability — — 75,670,977

Amortization of (discounts) premiums on investments (1,320,546) 1,633,286 —

Gain on deconsolidation of Geneos — — (4,121,075)

Gain on remeasurement of investment in Geneos (165,215) — —

Loss on extinguishment of convertible August 2019 bonds — — 8,177,043

Gain on extinguishment of convertible senior notes — — (8,762,030)

Changes in operating assets and liabilities:

Deferred revenue, including from affiliated entity (85,989) (39,853) (62,353)

Cash flows from investing activities:

Proceeds from sale of investment of GeneOne — — 40,125,418

Decrease in cash resulting from the deconsolidation of Geneos — — (2,774,851)

Cash flows from financing activities:

Acquisition of non-controlling interest — — 2,379,969

Proceeds from Geneos issuance of note payable — — 171,620

Supplemental disclosure:

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

F-8

Inovio Pharmaceuticals, Inc.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. The Company

Inovio Pharmaceuticals, Inc. (the “Company” or “INOVIO”) is a biotechnology company focused on developing and commercializing DNA medicines to help treat and protect people from diseases associated with HPV, cancer, and infectious diseases. The Company’s goal is to advance its diverse pipeline of product candidates and deliver on the promise of DNA medicines technology in treating and preventing a wide array of diseases.

In clinical trials, the INOVIO's DNA medicine candidates have shown the ability to generate immune responses, especially CD4+, CD8+, and memory T-cell responses against targeted pathogens and cancers, via its precisely designed plasmids. These plasmids are delivered into cells using the Company's investigational proprietary smart device, CELLECTRA.

INOVIO's lead candidates are focused on diseases associated with HPV. In 2022, INOVIO announced data from a Phase 1/2 clinical trial with INO-3107 for the treatment of HPV-6 and HPV-11 associated RRP. In this trial, treatment with INO-3107 resulted in a statistically significant reduction of the median number of surgeries, a result that reinforces the Company's belief that DNA medicines may play a key role in the treatment of HPV-related diseases.

The Company's partners and collaborators include Advaccine Biopharmaceuticals Suzhou Co, ApolloBio Corporation, AstraZeneca, The Bill & Melinda Gates Foundation (Gates), Coalition for Epidemic Preparedness Innovations (CEPI), Defense Advanced Research Projects Agency (DARPA), The U.S. Department of Defense (DoD), HIV Vaccines Trial Network, International Vaccine Institute (IVI), Kaneka Eurogentec, National Cancer Institute (NCI), National Institutes of Health (NIH), National Institute of Allergy and Infectious Diseases (NIAID), the Parker Institute for Cancer Immunotherapy, Plumbline Life Sciences, Regeneron Pharmaceuticals, Richter-Helm BioLogics, Thermo Fisher Scientific, the University of Pennsylvania, the Walter Reed Army Institute of Research, and The Wistar Institute.

The Company and its collaborators are currently evaluating the feasibility of, or conducting or planning clinical studies of, DNA medicines for Ebola; HPV-related precancers, including cervical, vulvar, and anal dysplasia; HPV-related cancers, including head & neck; other HPV-related disorders, such as RRP; and GBM.

INOVIO was incorporated in Delaware in June 2001 and has its principal executive offices in Plymouth Meeting, Pennsylvania.

2. Summary of Significant Accounting Policies

Basis of Presentation and Liquidity

The Company incurred a net loss attributable to common stockholders of $279.8 million for the year ended December 31, 2022. The Company had working capital of $218.4 million and an accumulated deficit of $1.5 billion as of December 31, 2022. The Company has incurred losses in each year since its inception and expects to continue to incur significant expenses and operating losses for the foreseeable future in connection with the research and preclinical and clinical development of its product candidates. The Company’s cash, cash equivalents and short-term investments of $253.0 million as of December 31, 2022 are sufficient to support the Company's operations for a period of at least 12 months from the date it is issuing these financial statements.

In order to continue to fund future research and development activities, the Company will need to seek additional capital. This may occur through strategic alliance and licensing arrangements, grant agreements and/or future public or private debt or equity financings including At-the-Market Equity Offering Sales Agreements (“Sales Agreements”). The Company has a history of conducting debt and equity financings, including the receipt of net proceeds of $83.0 million, $47.7 million and $454.5 million under Sales Agreements during the years ending December 31, 2022, 2021 and 2020, respectively, and $162.1 million from a January 2021 underwritten public offering of common stock. During the year ended December 31, 2019, the Company also issued convertible notes and bonds in a series of private placement transactions. However, sufficient funding may not be available in the future, or if available, may be on terms that significantly dilute or otherwise adversely affect the rights of existing stockholders. If adequate funds are not available, the Company may need to delay, reduce the scope of or put on hold one or more of its clinical and/or preclinical programs.

The Company’s ability to continue its operations is dependent upon its ability to obtain additional capital in the future and achieve profitable operations. The Company expects to continue to rely on outside sources of financing to meet its capital needs and the Company may never achieve positive cash flow. These consolidated financial statements do not include any adjustments to the specific amounts and classifications of assets and liabilities, which might be necessary should Inovio be unable to continue as a going concern. The Company's consolidated financial statements as of and for the year ended December 31, 2022 have been prepared on a going concern basis, which contemplates the realization of assets and the settlement of

F-9

liabilities and commitments in the normal course of business for the foreseeable future. The Company has evaluated subsequent events after the balance sheet date through the date it issued these consolidated financial statements.

The Company is and, from time to time, may in the future be subject to various legal proceedings and claims arising in the ordinary course of business. The Company assesses contingencies to determine the degree of probability and range of possible loss for potential accrual in its consolidated financial statements. An estimated loss contingency is accrued in the consolidated financial statements if it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Legal proceedings, including litigation, government investigations and enforcement actions, could result in material costs, occupy significant management resources and entail civil and criminal penalties, even if the Company ultimately prevails. Any of the foregoing consequences could result in serious harm to the Company’s business, results of operations and financial condition.

Consolidation

The consolidated financial statements include the accounts of Inovio Pharmaceuticals, Inc. and its wholly-owned subsidiary Inovio Asia LLC.

Segment Reporting

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business as one segment operating primarily within the United States.

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, disclosures of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and short-term investments. The Company limits its exposure to credit loss by placing its cash and investments with high credit quality financial institutions. Additionally, the Company has established guidelines regarding diversification of its investments and their maturities which are designed to maintain principal and maximize liquidity.

The Company has contracts with certain of its customers that have represented more than 10% of the Company's total revenues, as discussed in Note 3.

Fair Value of Financial Instruments

The guidance regarding fair value measurements establishes a three-tier fair value hierarchy which prioritizes the inputs used in measuring fair value. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets that are accessible at the measurement date; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

The Company’s financial instruments include cash equivalents, short-term investments, investments in affiliated entities, accounts receivable, prepaid expenses and other assets, accounts payable and accrued expenses, and convertible senior notes. The carrying amounts of cash equivalents, accounts receivable, prepaid expenses and other assets, accounts payable and accrued expenses approximate the related fair values due to the short-term maturities of these instruments. Short-term investments are recorded at fair value on a recurring basis, based on current market valuations. The Company carries convertible senior notes at face value less unamortized debt discount and issuance costs on its consolidated balance sheet, and it presents the fair value of such convertible notes and bonds for disclosure purposes only.

Cash and Cash Equivalents

Cash equivalents are considered by the Company to be highly liquid investments purchased with original maturities of three months or less from the date of purchase. Cash and cash equivalents included certain money market accounts and U.S. treasury securities at December 31, 2022 and 2021.

Short-term Investments

The Company defines investments as income-yielding securities that can be readily converted into cash or equity investments classified as available-for-sale. Investments included mutual funds, U.S. treasury securities, commercial paper, certificates of deposit, U.S. agency mortgage-backed securities and an equity investment in the Company’s affiliated entity, PLS, at December 31, 2022 and 2021.

F-10

Short-term investments are recorded at fair value, based on current market valuations. Unrealized gains and losses on the Company's short-term debt investments are excluded from earnings and reported as a separate component of other comprehensive loss until realized. Realized gains and losses and unrealized gains and losses on available-for-sale equity securities are included in non-operating other income (expense) on theconsolidated statements of operations and are derived using the specific identification method for determining the cost of the securities sold.

Accounts Receivable

Accounts receivable are recorded at invoiced amounts and do not bear interest. The Company performs ongoing credit evaluations of its customers’ financial condition. Credit is extended to customers as deemed necessary and generally does not require collateral. Management believes that the risk of loss is significantly reduced due to the quality and financial position of the Company's customers.No allowance for doubtful accounts was deemed necessary at December 31, 2022 and 2021.

Fixed Assets

Property and equipment are stated at cost and depreciated using the straight-line method over the estimated useful life of the assets, generally three to five years. Leasehold improvements are amortized over the shorter of the remaining term of the related leases or the estimated economic useful lives of the improvements. Repairs and maintenance are expensed as incurred.

Long-Lived Assets

All long-lived assets are reviewed for impairment in value when changes in circumstances dictate, based upon undiscounted future operating cash flows, and appropriate losses are recognized and reflected in current earnings, to the extent the carrying amount of an asset exceeds its estimated fair value determined by the use of appraisals, discounted cash flow analyses or comparable fair values of similar assets. The Company has not recognized any losses on long-lived assets through December 31, 2022.

Valuation of Intangible Assets and Goodwill

Intangible assets are amortized over their estimated useful lives ranging from two to 18 years. Acquired intangible assets are continuously being developed for the future economic viability contemplated at the time of acquisition. The Company is concurrently conducting preclinical studies and clinical trials using the acquired intangibles and has entered into licensing agreements for the use of these acquired intangibles.

License costs are recorded based on the fair value of consideration paid and are amortized using the straight-line method over the shorter of the expected useful life of the underlying patents or the term of the related license agreement to the extent the license has an alternative future use. As of December 31, 2022 and 2021, the Company’s intangible assets resulting from prior acquisitions of other companies, and additional intangibles including license costs, net of accumulated amortization, totaled $2.1 million and $2.6 million, respectively.

The determination of the value of intangible assets requires management to make estimates and assumptions that affect the Company’s consolidated financial statements. The Company assesses potential impairments to intangible assets when there is evidence that events or changes in circumstances indicate that the carrying amount of an asset may not be recovered. The Company’s judgments regarding the existence of impairment indicators and future cash flows related to intangible assets are based on operational performance of its acquired businesses, market conditions and other factors. If impairment is indicated, the Company will reduce the carrying value of the intangible asset to fair value. While current and historical operating and cash flow losses are potential indicators of impairment, the Company believes the future cash flows to be received from its intangible assets will exceed the intangible assets’ carrying value, and accordingly, the Company has not recognized any impairment losses through December 31, 2022.

Goodwill represents the excess of acquisition cost over the fair value of the net assets of acquired businesses. Goodwill is reviewed for impairment at least annually at November 30, or more frequently if an event occurs indicating the potential for impairment. During its goodwill impairment review, the Company may assess qualitative factors to determine whether it is likely that the fair value of its reporting unit is less than its carrying amount, including goodwill. The qualitative factors include, but are not limited to, macroeconomic conditions, industry and market considerations, and the overall financial performance of the Company. If, after assessing the totality of these qualitative factors, the Company determines that it is not likely that the fair value of its reporting unit is less than its carrying amount, then no additional assessment is deemed necessary. Otherwise, the Company will proceed to perform the impairment test in which the fair value of the reporting unit is compared with its carrying amount, and an impairment charge will be recorded for the amount by which the carrying amount exceeds the reporting unit's fair value, if any. The Company performed its annual assessment for goodwill impairment as of November 30, 2022, identifying no impairment.

Although there are inherent uncertainties in this assessment process, the estimates and assumptions the Company is using are consistent with its internal planning. If these estimates or their related assumptions change in the future, the Company may be required to record an impairment charge on all or a portion of its goodwill and intangible assets. Furthermore, the Company

F-11

cannot predict the occurrence of future impairment triggering events nor the impact such events might have on its reported asset values. Future events could cause the Company to conclude that impairment indicators exist and that goodwill or other intangible assets associated with its acquired businesses are impaired. Any resulting impairment loss could have an adverse impact on the Company’s results of operations. See Note 8 for further discussion of the Company’s goodwill and intangible assets.

Income Taxes

The Company recognizes deferred tax assets and liabilities for temporary differences between the financial reporting basis and the tax basis of the Company’s assets and liabilities along with net operating loss and tax credit carry forwards. The Company records a valuation allowance against its deferred tax assets to reduce the net carrying value to an amount that it believes is more likely than not to be realized. When the Company establishes or reduces the valuation allowance against its deferred tax assets, its provision for income taxes will increase or decrease, respectively, in the period such determination is made.

Valuation allowances against the Company’s deferred tax assets were $299.1 million and $237.2 million at December 31, 2022 and 2021, respectively. Changes in the valuation allowances, when they are recognized in the provision for income taxes, are included as a component of the estimated annual effective tax rate.

Revenue Recognition

The Company recognizes revenue, in accordance with Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (“Topic 606”), when it transfers promised goods or services to customers in an amount that reflects the consideration to which it expects to be entitled in exchange for those goods or services. To determine revenue recognition for contracts with customers, the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the Company satisfies its performance obligations. At contract inception, the Company assesses the goods or services agreed upon within each contract and assess whether each good or service is distinct and determine those that areperformance obligations. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied.

Collaborative Arrangements

The Company assesses whether its collaboration agreements are subject to ASC Topic 808: Collaborative Arrangements (“Topic 808”) based on whether they involve joint operating activities and whether both parties have active participation in the arrangement and are exposed to significant risks and rewards. To the extent that the arrangement falls within the scope of Topic 808 and the Company concludes that its collaboration partner is not a customer, the Company presents such payments as a reduction of research and development expense. If payments from the collaboration partner to the Company represent consideration from a customer, then the Company accounts for those payments within the scope of ASU Topic 606.

The Company enters into collaborative arrangements with partners that typically include payment of one or more of the following: (i) license fees; (ii) product supply services; (iii) milestone payments related to the achievement of developmental, regulatory, or commercial goals; and (iv) royalties on net sales of licensed products. Where a portion of non-refundable, upfront fees or other payments received are allocated to continuing performance obligations under the terms of a collaborative arrangement, they are recorded as deferred revenue and recognized as revenue when (or as) the underlying performance obligation is satisfied.

As part of the accounting for these arrangements, the Company must develop estimates and assumptions that require judgment of management to determine the underlying stand-alone selling price for each performance obligation which determines how the transaction price is allocated among the performance obligation. The standalone selling price may include items such as forecasted revenues, development timelines, discount rates and probabilities of technical and regulatory success. The Company evaluates each performance obligation to determine if it can be satisfied at a point in time or over time. In addition, variable consideration must be evaluated to determine if it is constrained and, therefore, excluded from the transaction price.

License Fees

If a license to intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company will recognize revenues from non-refundable, up-front fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition.

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Product Supply Services

Arrangements that include a promise for future supply of drug product for either clinical development or commercial supply at the licensee’s discretion are generally considered as options. The Company assesses if these options provide a material right to the licensee and if so, they are accounted for as separate performance obligations. The Company evaluates whether it is the principal or agent in the arrangement. The Company had determined that it is the principal in the current arrangements as the Company controls the product supply before it is transferred to the customer.

Milestone Payments

At the inception of each arrangement that includes milestone payments (variable consideration), the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company's or its collaboration partner’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Company re-evaluates the probability of achieving such milestones and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration or other revenues and earnings in the period of adjustment.

Royalties

For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and for which the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, the Company has not recognized any royalty revenue resulting from any of its collaborative arrangements.

Grants

The Company accounts for various grant agreements under the contributions guidance under Subtopic 958-605, Not-for-Profit Entities-Revenue Recognition, which is outside the scope of Topic 606, as the government agencies granting the Company funds are not receiving reciprocal value for their contributions. All contributions received from current grant agreements are recorded as a contra-expense as opposed to revenue on the consolidated statement of operations.

Foreign Currency Transactions

The functional and presentation currency of the Company is the U.S. dollar. Transactions denominated in a currency other than the functional currency are recorded on the initial recognition at the exchange rate at the date of the transaction. After initial recognition, monetary assets and liabilities denominated in foreign currency are translated at the end of each reporting period into the functional currency at the exchange rate at that date. The cumulative translation adjustment is included in the accumulated other comprehensive income (loss) within the statement of stockholders' equity. Exchange differences are included in general and administrative expenses in the consolidated statement of operations. Non-monetary assets and liabilities measured at cost are remeasured at the exchange rate at the date of the transaction.

Variable Interest Entities (VIE)

The Company evaluates its ownership, contractual and other interests in entities that are not wholly-owned to determine if these entities are VIEs, and, if so, whether the Company is the primary beneficiary of the VIE. In determining whether the Company is the primary beneficiary of a VIE and therefore required to consolidate the VIE, the Company applies a qualitative approach that determines whether it has both (1) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (2) the obligation to absorb losses of, or the rights to receive benefits from, the VIE that could potentially be significant to that VIE. The Company will continuously perform this assessment, as changes to existing relationships or future transactions may result in the consolidation or deconsolidation of a VIE.

Equity Investments

Under ASC Topic 321, Investments - Equity Securities, the Company must measure equity investments (except those accounted for under the equity method, those that result in consolidation of the investee and certain other investments) at fair value and recognize any changes in fair value in the consolidated statement of operations. The Company can elect a measurement alternative for equity investments that do not have readily determinable fair values and do not qualify for the practical expedient in ASC Topic 820, Fair Value Measurement, to estimate fair value using the net asset value per share (or its equivalent). The Company's equity investments that do not have readily determinable fair values and do not qualify for the net asset value practical expedient for estimating fair value are measured at cost, less any impairments, plus or minus changes resulting from observable price changes in orderly transactions for identifiable or similar investments of the same issuer.

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Research and Development Expenses

The Company’s activities have largely consisted of research and development efforts related to developing electroporation delivery technologies, DNA vaccines, DNA immunotherapies and dMABs. Research and development expenses consist of expenses incurred in performing research and development activities including salaries and benefits, facilities and other overhead expenses, clinical trials, contract services and other outside expenses. Research and development expenses are charged to operations as they are incurred. These expenses result from the Company's independent research and development efforts as well as efforts associated with collaborations and licensing arrangements. The Company reviews and accrues clinical trial expense based on work performed, which relies on estimates of total costs incurred based on participant enrollment, completion of studies and other events. Accrued clinical trial costs are subject to revisions as trials progress. Revisions are charged to expense in the period in which the facts that give rise to the revision become known. Historically, revisions have not resulted in material changes to research and development expense; however, a modification in the protocol of a clinical trial or cancellation of a trial could result in a charge to the Company's results of operations.

Advance payments for goods or services to be rendered in the future for use in research and development activities are deferred and included in prepaid expenses and other assets. The deferred amounts are expensed as the related goods are delivered or the services are performed.

Net Loss Per Share

Basic net loss per share is computed by dividing the net loss for the year by the weighted average number of shares of common stock outstanding during the year. Diluted net loss per share is calculated in accordance with the treasury stock method for the outstanding stock options and restricted stock units ("RSUs") and reflects the potential dilution that would occur if securities or other contracts to issue common stock were exercised or converted to common stock. The dilutive impact of the outstanding Notes and Bonds issued by the Company (discussed in Note 9) has been considered using the "if-converted" method. The calculation of diluted net loss per share requires that, to the extent the average market price of the underlying shares for the reporting period exceeds the exercise price of the options or other securities and the presumed exercise of such securities are dilutive to net loss per share for the period, an adjustment to net loss used in the calculation is required to remove the change in fair value of such securities from the numerator for the period. Likewise, an adjustment to the denominator is required to reflect the related dilutive shares, if any. For the years ended December 31, 2022, 2021 and 2020, basic and diluted net loss per share are the same, as the assumed exercise or settlement of stock options, RSUs and the potentially dilutive shares issuable upon conversion of the Notes and Bonds are antidilutive.

The following table summarizes potential shares of common stock that were excluded from diluted net loss per share calculation because of their anti-dilutive effect:

Year Ended December 31,

Leases

For its long-term operating leases, the Company recognized an operating lease right-of-use asset and an operating lease liability on its consolidated balance sheets. The lease liability is determined as the present value of future lease payments using an estimated rate of interest that the Company would pay to borrow equivalent funds on a collateralized basis at the lease commencement date. The right-of-use asset is based on the liability adjusted for any prepaid or deferred rent. The Company determines the lease term at the commencement date by considering whether renewal options and termination options are reasonably assured of exercise.

Fixed rent expense for the Company's operating leases is recognized on a straight-line basis over the term of the lease and is included in operating expenses on the consolidated statements of operations. Variable lease payments including lease operating expenses are recorded as incurred.

Stock-Based Compensation

The Company incurs stock-based compensation expense related to RSUs and stock options. The fair value of restricted stock is determined by the closing price of the Company's common stock reported on the Nasdaq Global Select Market on the

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date of grant. The Company estimates the fair value of stock options granted using the Black-Scholes option pricing model. The Black-Scholes option pricing model was developed for use in estimating the fair value of traded options, which have no vesting restrictions and are fully transferable. In addition, option valuation models require the input of subjective assumptions, including the expected stock price volatility and expected option life. The Company amortizes the fair value of the awards on a straight-line basis over the requisite vesting period of the awards. Expected volatility is based on historical volatility. The expected life of options granted is based on historical expected life. The risk-free interest rate is based on the U.S. Treasury yield in effect at the time of grant. The dividend yield is based on the fact that no dividends have been paid historically and none are currently expected to be paid in the foreseeable future. The Company recognizes forfeitures as they occur.

The weighted average assumptions used in the Black-Scholes model for option grants to employees and directors are presented below:

Year Ended December 31,

Expected volatility 94% 93% 78%

Expected life in years 5.7 6 6

Dividend yield — — —

The weighted average assumptions used in the Black-Scholes model for option grants to non-employees are presented below:

Year Ended December 31,

Expected volatility 87% 87% 76%

Expected life in years 10 10 10

Dividend yield — — —

Recent Accounting Pronouncements

The recent accounting pronouncements below may have a significant effect on the Company's financial statements. Recent accounting pronouncements that are not anticipated to have an impact on or are unrelated to the Company's financial condition, results of operations, or related disclosures are not discussed.

ASU No. 2020-06. In August 2020, the FASB issued ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”), which simplifies the guidance on an issuer’s accounting for convertible instruments and contracts in its own equity. ASU 2020-06 was effective for public entities for fiscal years beginning after December 15, 2021, and interim periods within those fiscal years. The Company adopted ASU 2020-06 as of January 1, 2022 on a modified retrospective basis and recorded a net reduction in accumulated deficit of $1.8 million, a decrease in additional paid-in capital of $3.3 million, and an increase in convertible senior notes of $1.5 million to reflect the impact of the accounting change. The Company derecognized the related deferred tax liabilities of $1.5 million with a corresponding adjustment to the valuation allowance, resulting in no net impact to the cumulative adjustment to retained earnings (see Note 9, Convertible Debt, for additional information).

3. Revenue Recognition and Concentration of Credit Risk

During the years ended December 31, 2022, 2021 and 2020, the Company recognized revenue from various license and other agreements. The following table indicates the percentage of total revenues in excess of 10% with any single customer:

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Of the total revenue recognized during the year ended December 31, 2022, $14,000 was in deferred revenue as of December 31, 2021. During the year ended December 31, 2021, the Company recognized revenue of $46,000 that was included in deferred revenue at December 31, 2020. Performance obligations are generally satisfied within 12 months of the initial contract date.

As of December 31, 2022, all of the Company's accounts receivable was attributable to the CEPI MERS grant. As of December 31, 2021, $3.6 million, or 65%, and $1.9 million, or 34%, of the Company's accounts receivable was attributable to the DoD and CEPI MERS grants, respectively. There is minimal credit risk with these customers based upon collection history, their size and financial condition. Accordingly, the Company does not consider it necessary to record a reserve for uncollectible accounts receivable.

4. Collaborative Agreements

Advaccine Biopharmaceuticals Suzhou Co., Ltd.

On December 31, 2020, the Company entered into a Collaboration and License Agreement with Advaccine Biopharmaceuticals Suzhou Co., Ltd. (“Advaccine”), which was amended and restated on June 7, 2021 (as amended and restated, the “Advaccine Agreement”). Under the terms of the Advaccine Agreement, the Company granted to Advaccine the exclusive right to develop, manufacture and commercialize the Company’s vaccine candidate INO-4800 within the territories of China, Taiwan, Hong Kong and Macau (referred to collectively as “Greater China”) and 33 additional countries in Asia. Advaccine does not have the right to grant sublicenses, other than to affiliated entities, without the Company’s express prior written consent. As part of the collaboration, Advaccine also granted to the Company a non-exclusive license to certain DNA vaccine manufacturing processes.

The June 2021 amendment related to a collaboration between the Company and Advaccine to jointly conduct a global Phase 3 segment of the Company’s clinical trial of INO-4800. The parties were jointly participating in the trial and were to equally share the global development costs for the trial, including the Company’s manufacturing costs to supply INO-4800. Advaccine agreed to be fully responsible for conducting the trial in Greater China, including its costs and expenses incurred. On October 27, 2022, the Company announced that it had discontinued its internally funded efforts to develop INO-4800 as a COVID-19 heterologous booster vaccine. Advaccine will continue to develop INO-4800 with its own resources under the terms of the Advaccine Agreement.

Under the Advaccine Agreement, Advaccine made an upfront payment to the Company of $3.0 million in January 2021. In addition to the upfront payment, the Company is entitled to receive up to an aggregate of $200.0 million upon the achievement of specified milestones related to the development, regulatory approval and commercialization of INO-4800, including the achievement of specified net sales thresholds for INO-4800 in Greater China and the additional covered territories, if approved. The Company will also be entitled to receive a royalty equal to a high single-digit percentage of annual net sales in each region within the licensed territory, subject to reduction in the event of competition from biosimilar products in a particular region and in other specified circumstances. Advaccine’s obligation to pay royalties will continue, on a licensed product-by-licensed product basis and region-by-region basis, for ten years after the first commercial sale in a particular region within Greater China or, if later, until the expiration of the last-to-expire patent covering a given licensed product in a given region.

Beginning in the first calendar year following the first commercial sale of INO-4800 in the licensed territory outside of Greater China, Advaccine will pay the Company an annual maintenance fee of $1.5 million for a period of five years, which fee will be creditable against any royalties payable by Advaccine with respect to sales outside of Greater China.

Under the Advaccine Agreement, the Company will supply Advaccine’s clinical requirements of INO-4800 and devices, although Advaccine may manufacture INO-4800 for its clinical use and may procure alternate suppliers. Advaccine is responsible for the manufacture and supply of INO-4800 itself or through a contract manufacturer for commercial use. Upon Advaccine’s reasonable request, the parties may negotiate a separate clinical and/or commercial supply agreement.

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The Advaccine Agreement will continue in force on a region-by-region basis until Advaccine has no remaining royalty obligations in such region. Either party may terminate the Advaccine Agreement (i) in the event the other party shall have materially breached its obligations thereunder and such default shall have continued for a specified period after written notice thereof or (ii) upon the bankruptcy or insolvency of the other party. In addition, the Company may terminate the agreement, upon prior written notice, if Advaccine (i) ceases all development or commercialization activities for at least nine months, subject to certain exceptions, or (ii) challenges the validity, enforceability or scope of any of the patents licensed by the Company to Advaccine under the Advaccine Agreement, subject to certain conditions. Advaccine may terminate the Advaccine Agreement at any time for convenience upon nine months’ written notice to the Company, if such notice is provided before the first commercial sale of INO-4800 in the licensed territory, or18 months’ written notice thereafter; provided that the Company may accelerate the effectiveness of such termination to the extent permitted by law.

The Company evaluated the terms of the Advaccine Agreement under ASC Topics 606 and 808 at inception and determined that the contract was with a customer and therefore should be accounted for under ASC Topic 606. The license to INO-4800 in the territories was identified as the only distinct performance obligation on a standalone basis as of the inception of the Advaccine Agreement. The Company concluded that the license was distinct from potential future manufacturing and supply obligations. The Company further determined that the transaction price under the Advaccine Agreement consisted of the $3.0 million upfront payment received in January 2021 plus a $2.0 million milestone payment which was achieved upon contract signing. The future potential milestone amounts were not included in the transaction price, as they were all determined to be fully constrained. As part of the evaluation of the development and regulatory milestones constraint, the Company determined that the achievement of such milestones is contingent upon success in future clinical trials and regulatory approvals, each of which is uncertain. Future potential milestone amounts may be recognized as revenue under the Advaccine Agreement, as well as under other collaborative research and development arrangements, if unconstrained. Reimbursable program costs will be recognized proportionately with the performance of the underlying services or delivery of drug supply and are excluded from the transaction price.

Under Topic 606, the entire transaction price of $5.0 million was allocated to the license performance obligation. The Company recognized $0, $0 and $5.0 million of revenue for the years ended December 31, 2022, 2021, and 2020, respectively, under the Advaccine Agreement.

In connection with the June 2021 amendment, the Company determined that the global Phase 3 trial component of the agreement was a collaboration and not a contract with a customer and therefore accounted for the June 2021 amendment under ASC Topic 808. Reimbursements from Advaccine were recognized as contra-research development expense on the consolidated statement of operations once earned and collectibility was assured.During the years ended December 31, 2022, 2021 and 2020 the Company received funding of $1.2 million, $4.5 million and $0, respectively, from Advaccine that was recorded as contra-research and development expense.

ApolloBio Corporation

On December 29, 2017, the Company entered into an Amended and Restated License and Collaboration Agreement (the "ApolloBio Agreement"),with ApolloBio Corporation ("ApolloBio"), with an effective date of March 20, 2018. Under the terms of the ApolloBio Agreement, the Company granted to ApolloBio the exclusive right to develop and commercialize VGX-3100, its DNA immunotherapy product candidate designed to treat pre-cancers caused by HPV, within the agreed upon territories.

The Company is entitled to receive up to an aggregate of $20.0 million, less required income, withholding or other taxes, upon the achievement of specified milestones related to the regulatory approval of VGX-3100 in accordance with the ApolloBio Agreement. In the event that VGX-3100 is approved for marketing, the Company will be entitled to receive royalty payments based on a tiered percentage of annual net sales, with such percentage being in the low- to mid-teens, subject to reduction in the event of generic competition in a particular territory. ApolloBio’s obligation to pay royalties will continue for 10 years after the first commercial sale in a particular territory or, if later, until the expiration of the last-to-expire patent covering the licensed products in the specified territory.

The ApolloBio Agreement will continue in force until ApolloBio has no remaining royalty obligations. Either party may terminate the ApolloBio Agreement in the event the other party shall materially breach or default in the performance of its material obligations thereunder and such default continues for a specified period after written notice thereof. In addition, ApolloBio may terminate the ApolloBio Agreement at any time beginning one year after the effective date for any reason upon 90 days written notice to the Company.

For the years ended December 31, 2022, 2021 and 2020, there has been no significant reimbursable program costs under the ApolloBio Agreement.

Coalition for Epidemic Preparedness Innovations

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The Company previously entered into agreements with CEPI pursuant to which the Company intended to develop vaccine candidates against Lassa fever and MERS. The goal of the collaboration between the Company and CEPI was to conduct research and development so that investigational stockpiles would be ready for clinical efficacy trial testing during potential disease outbreaks. The agreements with CEPI contemplated preclinical studies, as well as Phase 1 and Phase 2 clinical trials, occurring over multiple years. As part of the arrangement between the parties, CEPI agreed to fund up to an aggregate of $56 million of costs over a five-year period for preclinical studies, as well as planned Phase 1 and Phase 2 clinical trials, to be conducted by the Company and collaborators, with funding from CEPI based on the achievement of identified milestones. During the years ended December 31, 2022, 2021 and 2020, the Company received funding of $6.7 million, $10.0 million and $6.4 million, respectively, related to these grants and recorded those payments as contra-research and development expense. As of December 31, 2022 and 2021, the Company had an accounts receivable balance of $1.7 million and $1.9 million, respectively, on the consolidated balance sheet related to these CEPI grants.

In November 2022, the Company announced that it and CEPI would discontinue the development of these product candidates targeting Lassa fever and MERS, following the initial analysis of data from the studies conducted by the Company and funded by CEPI.

In January 2020, CEPI awarded the Company a grant of up to $9.0 million to support preclinical and clinical development of INO-4800 through Phase 1 human testing in the United States. In April 2020, CEPI awarded the Company a grant of $6.9 million to work with the International Vaccine Institute ("IVI") and the Korea National Institute of Health ("KNIH") to conduct clinical trials of INO-4800 in South Korea, a grant of $5.0 million to accelerate development of the Company's next-generation intradermal electroporation device, known as CELLECTRA 3PSP, for the intradermal delivery of INO-4800, and a grant of $1.3 million to support large-scale manufacturing of INO-4800. During the years ended December 31, 2022, 2021 and 2020, the Company received funding of $1.1 million, $6.9 million and $10.0 million, respectively, from CEPI related to these grants for INO-4800 and recorded such amounts as contra-research and development expense. As of December 31, 2022 and 2021, the Company had $2.3 million and $1.8 million recorded as deferred grant funding on the consolidated balance sheet related to the CEPI grants related to INO-4800, respectively

Bill & Melinda Gates Foundation

In October 2018, Gates awarded and funded the Company a grant of $2.2 million to advance the development of dMAbs to address issues in infectious disease prevention and therapy. This technology has high relevance for the control of influenza and HIV. This next-generation approach to the delivery of monoclonal antibodies would make the technology accessible to low and middle-income countries. In August 2019, Gates funded an additional $1.1 million for the project. During the years ended December 31, 2022, 2021 and 2020, the Company recorded $233,000, $182,000 and $463,000, respectively, as contra-research and development expense related to the Gates dMAb grant. As of December 31, 2022 and 2021, the Company had $153,000 and $384,000 recorded as deferred grant funding on the consolidated balance sheet related to the grant, respectively.

In March 2020, Gates awarded and funded the Company a grant of $5.0 million to accelerate the development of the CELLECTRA 3PSP device for the intradermal delivery of INO-4800. During the years ended December 31, 2022, 2021 and 2020, the Company recorded $0, $893,000 and $4.1 million, respectively, as contra-research and development expense related to this Gates grant.

Department of Defense (DoD)

In June 2020, the Company entered into an Other Transaction Authority for Prototype Agreement (the “OTA Agreement”) with the DoD to fund the Company’s efforts in developing the CELLECTRA® 3PSP device and associated arrays to be used for delivery of INO-4800 against COVID-19. The total amount of funding provided to the Company under the OTA Agreement was $54.5 million. The Company determined that the OTA Agreement should be considered under Subtopic 958-605, Not-for-Profit Entities-Revenue Recognition, which is outside the scope of Topic 606, as the government agency granting the Company funds was not receiving reciprocal value for their contributions. The Company recorded contra-research development expense on the consolidated statement of operations in the same period that the underlying expenses were incurred. During the years ended December 31, 2022, 2021 and 2020, the Company recorded $6.1 million, $27.1 million and $21.2 million, respectively, as contra-research and development expense related to the OTA agreement

Additionally, in June 2020, the Company was awarded a fixed-price contract (the “Procurement Contract”) from the DoD for the purchase of the Company’s intradermal CELLECTRA® 2000 device and accessories. The total purchase price under the Procurement Contract was $16.8 million. The Company determined that the Procurement Contract fell under the scope of ASC Topic 606 as the contract was with a customer and the Company was able to satisfy its obligations under the arrangement. Performance obligations under the Procurement Contract consisted of the delivery of a specified number of CELLECTRA® 2000 devices and accessories. The total transaction price was allocated to the individual performance obligations based on the determined standalone selling price for the devices and accessories. In 2021, the DoD announced that it would discontinue funding for the Phase 3 segment of the Company's clinical trials for INO-4800 and in January 2022, the total purchase price under the Procurement Contract was reduced to $10.7 million. During the year ended December 31, 2022, all performance obligations under the Procurement Contract were satisfied. During the years ended December 31, 2022, 2021

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and 2020, the Company recorded revenue of $9.6 million, $755,000 and $0, respectively, from the Procurement Contract.

5. Short-term Investments and Fair Value Measurements

The following is a summary of available-for-sale securities as of December 31, 2022 and 2021:

*No single maturity date.

During the years ended December 31, 2022 and 2021, the Company recorded gross realized gain on investments of $21,000 and $394,000, respectively, and gross realized loss on investments of $4.1 million and $399,000, respectively. During the years ended December 31, 2022 and 2021, the Company recorded net unrealized loss on available-for-sale equity securities of $7.8 million and $3.2 million, respectively. No material balances were reclassified out of accumulated other comprehensive loss for the years ended December 31, 2022, 2021 and 2020. Interest and dividends on investments classified as available-for-sale are included in interest income in the consolidated statements of operations. As of December 31, 2022, the Company had 29 available-for-sale securities in a gross unrealized loss position, of which 21 with an aggregate total unrealized loss of $8.7 million were in such position for longer than 12 months.

The Company periodically reviews its portfolio of available-for-sale debt securities to determine if any investment is impaired due to credit loss or other potential valuation concerns. For the debt securities where the fair value of the investment is less than the amortized cost basis, the Company has assessed at the individual security level for various quantitative factors including, but not limited to, the nature of the investments, changes in credit ratings, interest rate fluctuations, industry analyst reports, and the severity of impairment. Unrealized losses on available-for-sale debt securities as of December 31, 2022 were primarily due to changes in interest rates, and not due to increased credit risks associated with specific securities. Based on the credit quality of the available-for-sale debt securities that are in an unrealized loss position, and the Company’s estimates of future cash flows to be collected from those securities, the Company believes the unrealized losses are not credit losses. Accordingly, at December 31, 2022, the Company has not recorded an allowance for credit losses related to its available-for-sale debt securities.

The following table presents the Company’s assets that were measured at fair value on a recurring basis, determined using the following inputs as of December 31, 2022:

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Fair Value Measurements at

Short-term investments

The following table presents the Company’s assets that were measured at fair value on a recurring basis, determined using the following inputs as of December 31, 2021:

Fair Value Measurements at

Short-term investments

Level 1 assets at December 31, 2022 and 2021 consisted of mutual funds and U.S. treasury securities held by the Company that are valued at quoted market prices, as well as the Company’s investment in its affiliated entity, PLS. The Company accounts for its investment in 597,808 common shares of PLS based on the closing price of the shares on the Korea New Exchange Market on the applicable balance sheet date. Unrealized gains and losses on the Company's equity securities are reported in the consolidated statement of operations as unrealized gain or loss on available-for-sale equity securities or as a gain or loss on investment in affiliated entity.

Level 2 assets at December 31, 2022 consisted of certificates of deposit and U.S. agency mortgage-backed securities held by the Company that are initially valued at the transaction price and subsequently valued, at the end of each reporting period, typically utilizing market observable data. Level 2 assets at December 31, 2021 consisted of commercial paper, certificates of deposit and U.S. agency mortgage-backed securities. The Company obtains the fair value of its Level 2 assets from a professional pricing service, which may use quoted market prices for identical or comparable instruments, or inputs other than quoted prices that are observable either directly or indirectly. The professional pricing service gathers quoted market prices and observable inputs from a variety of industry data providers. The valuation techniques used to measure the fair value of the Company's Level 2 financial instruments were derived from non-binding market consensus prices that are corroborated by observable market data, quoted market prices for similar instruments, or pricing models such as discounted cash flow techniques. The Company validates the quoted market prices provided by the primary pricing service by comparing the

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service's assessment of the fair values of the Company's investment portfolio balance against the fair values of the Company's investment portfolio balance obtained from an independent source.

There were no Level 3 assets held as of December 31, 2022 and 2021.

6. Certain Balance Sheet Items

Prepaid and other current assets at December 31, 2022 and 2021 consisted of the following:

Accounts payable and accrued expenses at December 31, 2022 and 2021 consisted of the following:

Accrued litigation settlement (a) 44,000,000 —

(a)In July 2022, the Company entered into a memorandum of understanding for the proposed settlement of the class action securities litigation described in this report under “Legal Proceedings.” The final judicial order for the settlement was issued in January 2023. The settlement consists of $30.0 million in cash and $14.0 million in shares of the Company's common stock to settle all outstanding claims. As of December 31, 2022, the Company's insurance carriers had paid the cash component of the proposed settlement, which amounts were being held in escrow. The Company's insurance carriers paid $252,000 of other expenses on behalf of the Company, which amounts are being offset against the insurers' cash commitment as part of the settlement.

7. Fixed Assets

Fixed assets at December 31, 2022 and 2021 consisted of the following:

Cost AccumulatedDepreciationandAmortization Net BookValue

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Depreciation expense for the years ended December 31, 2022, 2021 and 2020 was $3.7 million, $3.0 million and $3.0 million, respectively. The Company determined that the carrying value of these long-lived assets was not impaired during the periods presented. During the year ended December 31, 2022 the Company sold fixed assets with a net book value of $6.1 million and disposed of fixed assets with a net book value of $1.1 million. The Company has recorded a receivable from the sale of these assets of $6.1 million, which is included in prepaid expenses and other current assets on the consolidated balance sheet.

8. Goodwill and Intangible Assets

The following sets forth goodwill and intangible assets by major asset class:

Indefinite lived:

Definite lived:

(a)Bioject intangible assets represent the estimated fair value of developed technology and intellectual property which were recorded from an asset acquisition.

(b)Other intangible assets represent the estimated fair value of acquired intellectual property.

Aggregate amortization expense on intangible assets was $496,000, $520,000 and $547,000 for the years ended December 31, 2022, 2021 and 2020, respectively. Amortization expense related to intangible assets at December 31, 2022 is expected to be incurred as follows:

Year ending December 31,

There were no impairment or impairment indicators present and no losses were recorded during the years ended December 31, 2022, 2021 and 2020.

9. Convertible Debt

Convertible Senior Notes

On February 19, 2019 and March 1, 2019, the Company completed a private placement of $78.5 million aggregate principal amount of its 6.50% convertible senior notes due 2024 (the “Notes”). The Notes were sold in a private offering to

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qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended. Net proceeds from the offering were $75.7 million.

The Notes are senior unsecured obligations of the Company and accrue interest payable in cash semi-annually in arrears on March 1 and September 1 of each year at a rate of 6.50% per annum. The Notes mature on March 1, 2024, unless earlier converted, redeemed or repurchased. Prior to the close of business on the business day immediately preceding November 1, 2023, the Notes will be convertible at the option of the holders only upon the satisfaction of certain circumstances. Thereafter, the Notes will be convertible at the option of the holders at any time until the close of business on the scheduled trading day immediately before the maturity date. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of its common stock or a combination of cash and shares of its common stock, at its election. The initial conversion rate was 185.8045 shares per $1,000 principal amount of Notes (equivalent to an initial conversion price of approximately $5.38 per share), subject to adjustment upon the occurrence of specified events.

The Company may redeem all, or any portion, of the Notes for cash if the last reported sale price per share of the Company's common stock exceeds 130% of the conversion price on (i) each of at least 20 trading days (whether or not consecutive) during the 30 consecutive trading days ending on, and including, the trading day immediately before the Company sends the related redemption notice; and (ii) the trading day immediately before the date the Company sends such redemption notice. The redemption price will be equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date.

Initially, in accounting for the issuance of the Notes, the Company separated the Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the fair value of similar debt instruments, which do not have an associated convertible feature. The carrying amount of the equity component representing the conversion option for the Notes was $16.3 million and was recorded as a debt discount, which was being amortized to interest expense at an effective interest rate of 13.1%. In addition, the Company allocated $592,000 of debt issuance costs to the equity component and the remaining debt issuance costs of $2.2 million were allocated to the liability component, which were being amortized to interest expense under the effective interest rate method.

On January 1, 2022, the Company adopted ASU No. 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”), which is intended to simplify the accounting for convertible instruments. The ASU eliminates the cash conversion feature models in ASC 470-20, Debt with Conversion and Other Options, which required an issuer of certain convertible debt to separately account for embedded conversion features as a component of equity. Instead, an issuer will account for these securities as a single unit of account, unless the conversion feature meets certain criteria. The Company adopted the new standard using the modified retrospective method and recorded a net reduction to accumulated deficit of $1.8 million, a decrease to additional paid-in capital of $3.3 million, and an increase to convertible senior notes of $1.5 million to reflect the impact of the accounting change. The Notes are now accounted for as a single liability measured at amortized cost, as no other embedded features require bifurcation and recognition as derivatives.

The balance of the Notes at December 31, 2022 was as follows:

Principal amount converted into common shares (62,085,000)

Unamortized debt issuance cost (155,815)

For the years ended December 31, 2022, 2021 and 2020, the Company recognized $1.3 million, $1.9 million and $6.9 million, respectively, of interest expense related to the Notes, of which $1.1 million, $1.1 million and $4.1 million, respectively, related to the contractual interest coupon.

As of December 31, 2022, future minimum payments due under the Notes, representing contractual amounts due, including interest based on the fixed rate of 6.5% per annum, were as follows:

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December 2019 Convertible Bonds

On December 26, 2019, the Company closed a private placement of convertible promissory notes (the “December 2019 Bonds”) with an aggregate principal amount of 4.7 billion KRW (USD $4.1 million based on the exchange rate on the date of issuance) issued to a Korea-based institutional investor. Net proceeds from the offering were $4.0 million.

The December 2019 Bonds, which were unsecured obligations of the Company, were issued on December 31, 2019 and accrue interest at a coupon rate of 1.00% per annum, payable quarterly. The December 2019 Bonds were scheduled to mature on December 31, 2024, unless earlier converted or repurchased. On March 17, 2021, the December 2019 Bonds were converted in full into an aggregate of 1,009,450 shares of the Company's common stock, leaving no further December 2019 Bonds outstanding. Upon conversion, the $4.4 million carrying value of the December 2019 Bonds was reclassified to stockholders' equity.

During the year ended December 31, 2021, the Company recognized $50,000 of interest expense related to the December 2019 Bonds, of which $9,000 related to the contractual interest coupon. The effective interest rate of the December 2019 Bonds was 6.2%.

10. Stockholders’ Equity

Preferred Stock

Shares Outstanding as ofDecember 31,

Shares Authorized Shares Issued 2022 2021

The holder of a share or shares of Series C preferred stock has the right at any time, at such holder’s option, to convert all or any lesser portion of such holder’s shares of the preferred stock into fully paid and non-assessable shares of common stock. As of December 31, 2021, the conversion value was $27.20 per share, such that the outstanding shares of Series C preferred stock were convertible into an aggregate of 3,309 shares of common stock.

Issuances of Common Stock

On November 9, 2021, the Company entered into an ATM Equity OfferingSM Sales Agreement (the “2021 Sales Agreement”) with outside sales agents (collectively, the “Sales Agents”) for the offer and sale of its common stock for an aggregate offering price of up to $300.0 million. The 2021 Sales Agreement provides that the Sales Agents will be entitled to compensation in an amount equal to up to 3.0% of the gross sales proceeds of any common stock sold through the Sales Agents under the 2021 Sales Agreement. During the years ended December 31, 2022 and 2021, the Company sold 34,445,743 and 6,955,341 shares, respectively, of its common stock under the 2021 Sales Agreement. The sales were made at a weighted average price of $2.44 and $6.96 per share, respectively, resulting in aggregate net proceeds of $83.0 million and $47.7 million, respectively. As of December 31, 2022 there was $167.4 million of remaining capacity under the 2021 Sales Agreement.

On January 25, 2021, the Company closed an underwritten public offering of 20,355,000 shares of common stock at a public offering price of $8.50 per share. The net proceeds to the Company, after deducting the underwriters' discounts and commissions and other offering expenses, were $162.1 million.

Stock Options and Restricted Stock Units

The Company has a stock-based incentive plan, the 2016 Omnibus Incentive Plan (as amended to date, the "2016 Incentive Plan"), pursuant to which the Company may grant stock options, restricted stock awards, RSUs and other stock-based awards or short-term cash incentive awards to employees, directors and consultants.

The 2016 Incentive Plan was originally approved by the Company's stockholders on May 13, 2016, and an amendment to the plan to increase the number of shares available for issuance was approved by the stockholders on May 8, 2019. As of December 31, 2022, the maximum number of shares of the Company’s common stock available for issuance over the term of the 2016 Incentive Plan was 22,000,000 shares. On the first business day of each calendar year, the maximum number of shares is increased by 2,000,000 shares of common stock unless the Company's board of directors determines, prior to January 1 for any such calendar year, to increase the maximum amount by a lesser amount. On January 1, 2022 and again on January 1, 2023, the maximum number of shares increased by 2,000,000. At December 31, 2022, the Company had 3,831,240 shares of common stock available for future grant under the 2016 Incentive Plan, 2,446,257 shares underlying outstanding but unvested service-based RSUs, options outstanding to purchase 10,132,969 shares of common stock and 111,941 shares of performance-based RSUs outstanding under the 2016 Incentive Plan. The awards granted and available for future grant under the 2016 Incentive

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Plan generally vest over three years and have a maximum contractual term of ten years. The 2016 Incentive Plan terminates by its terms on March 9, 2026.

On June 24, 2022, the Company's board of directors adopted a stock-based incentive plan (the "2022 Inducement Plan"), which provides for the discretionary grant of nonstatutory stock options, stock appreciation rights, restricted stock awards, RSU awards, performance awards, and other awards to individuals as a material inducement to entering into employment with the Company. The aggregate number of shares of the Company’s common stock that may be issued under the 2022 Inducement Plan will not exceed 2,000,000 shares. At December 31, 2022 the Company had 1,703,750 shares of common stock available for future grant under the 2022 Inducement Plan, 110,000 shares underlying outstanding but unvested RSUs and options outstanding to purchase 186,250 shares of common stock under the 2022 Inducement Plan. The 2022 Inducement Plan can be terminated by the Company's board of directors at any time.

The Amended and Restated 2007 Omnibus Incentive Plan (the "2007 Incentive Plan") was adopted on March 31, 2007 and terminated by its terms on March 31, 2017. At December 31, 2022, the Company had options outstanding to purchase 1,902,329 shares of common stock under the 2007 Incentive Plan. The awards granted under the 2007 Incentive Plan generally vest over three years and have a maximum contractual term of ten years.

Total employee and director stock-based compensation expense recognized in the consolidated statements of operations for the years ended December 31, 2022, 2021 and 2020 was $22.2 million, $25.0 million and $14.5 million, respectively, of which $8.8 million, $13.4 million and $8.0 million was included in research and development expenses and $13.4 million, $11.6 million and $6.5 million was included in general and administrative expenses, respectively. The Company entered into a Separation Agreement with its former President and Chief Executive Officer on May 10, 2022, under which outstanding RSUs as of the separation date were fully vested, and one-half of the RSUs were settled in the Company's common stock and the remainder settled in cash. The officer's stock options will continue to vest over a certain period and will remain exercisable until five years after the separation date. Stock-based compensation for the year ended December 31, 2022 included a $4.2 million charge related to these RSU and stock option modifications.

At December 31, 2022 and 2021, there was $10.5 million and $16.5 million, respectively, of total unrecognized compensation expense related to unvested stock options, which is expected to be recognized over a weighted-average period of 1.6 years and 2.0 years, respectively.

At December 31, 2022 and 2021, there was $7.2 million and $13.4 million, respectively, of total unrecognized compensation expense related to unvested RSUs, which is expected to be recognized over a weighted-average period of 1.7 years and 1.8 years, respectively.

The fair value of stock options granted to non-employees was estimated using the Black-Scholes pricing model. Total stock-based compensation expense for stock options and RSUs granted to non-employees for the years ended December 31, 2022, 2021 and 2020 was $1.3 million, $1.4 million and $1.2 million, respectively. As of December 31, 2022, options to purchase 665,875 shares of common stock granted to non-employees remained outstanding.

The following table summarizes total stock options outstanding at December 31, 2022:

Options Outstanding Options Exercisable

At December 31, 2022, the aggregate intrinsic value of options outstanding was $0, the aggregate intrinsic value of options exercisable was $0, and the weighted average remaining contractual term of options exercisable was 5.7 years.

At December 31, 2022, the aggregate intrinsic value of unvested RSUs was $4.0 million and the aggregate intrinsic value of RSUs which vested during the year ended December 31, 2022 was $4.6 million.

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At December 31, 2022, options to purchase 12,221,548 shares of common stock and 2,556,257 RSUs were expected to vest.

Stock option activity under the Company’s equity incentive plans during the year ended December 31, 2022 was as follows:

Number ofShares Weighted-AverageExercise Price

Restricted stock unit activity under the Company’s equity incentive plans during the year ended December 31, 2022 was as follows:

Number ofShares

The weighted average exercise price per share was $8.47 for the 77,250 options which expired during the year ended December 31, 2022, $4.56 for the 7,000 options which expired during the year ended December 31, 2021 and $4.44 for the 78,750 options which expired during the year ended December 31, 2020.

The weighted average grant date fair value per share was $2.34, $7.61 and $6.87 for options granted during the years ended December 31, 2022, 2021 and 2020, respectively.

The weighted average grant date fair value was $3.12, $10.37 and $9.12 per share for RSUs granted during the years ended December 31, 2022, 2021 and 2020, respectively.

The Company received $283,000, $6.7 million and $12.3 million in proceeds from the exercise of stock options during the years ended December 31, 2022, 2021 and 2020, respectively. The aggregate intrinsic value of options exercised was $81,000, $7.0 million and $14.2 million during the years ended December 31, 2022, 2021 and 2020, respectively.

As of December 31, 2022, theCompanyhad111,941performance-based RSUs outstanding, which were granted to key employees in August 2020. The underlying performance milestones of the RSUs were not probable of achievement as of December 31, 2022, and no stock-based compensation expense has been recognized to date for the performance-based RSUs.

11. Commitments and Contingencies

Leases

The Company leases approximately 82,200 square feet of office, laboratory, and manufacturing space in San Diego, California and 57,360 square feet of office space in Plymouth Meeting, Pennsylvania under various non-cancellable operating lease agreements with remaining lease terms as of December 31, 2022 of 0.9 years to 7.0 years, which represent the non-cancellable periods of the leases. The Company has excluded the extension options from its lease terms in the calculation of future lease payments as they are not reasonably certain to be exercised. The Company's lease payments consist primarily of fixed rental payments for the right to use the underlying leased assets over the lease terms as well as payments for common area maintenance and administrative services. The Company has received customary incentives from its landlords, such as reimbursements for tenant improvements and rent abatement periods, which effectively reduce the total lease payments owed for these leases.

The Company performed an evaluation of its contracts with customers and suppliers in accordance with ASC Topic 842 and determined that, except for the real estate leases described above and various copier leases, none of its other contracts contain a right-of-use asset.

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Operating lease right-of-use assets and liabilities on the consolidated balance sheet represents the present value of the remaining lease payments over the remaining lease terms. Payments for additional monthly fees to cover the Company's share of certain facility expenses are not included in operating lease right-of-use assets and liabilities. The Company uses its incremental borrowing rate to calculate the present value of its lease payments, as the implicit rates in the leases are not readily determinable.

As of December 31, 2022, the maturities of the Company's operating lease liabilities were as follows:

Year ending December 31,

Total remaining lease payments 20,090,000

Less: present value adjustment (4,630,000)

Total operating lease liabilities 15,460,000

Long-term operating lease liabilities $ 12,656,000

Weighted-average remaining lease term 5.9 years

Weighted-average discount rate 8.6 %

Lease costs included in operating expenses in the consolidated statements of operations for the years ended December 31, 2022, 2021 and 2020 were $3.4 million, $3.4 million and $3.4 million, respectively. Operating lease costs consisting of the fixed lease payments included in operating lease liabilities are recorded on a straight-line basis over the lease terms. Variable lease costs are recorded as incurred.

In the fourth quarter of 2019, the Company entered into two agreements to sublease a total of approximately 13,500 square feet in its Plymouth Meeting headquarters with one period through March 31, 2025 and the other month-to-month after December 31, 2022.

In the normal course of business, the Company is a party to a variety of agreements pursuant to which it may be obligated to indemnify the other party. It is not possible to predict the maximum potential amount of future payments under these types of agreements due to the conditional nature of the Company's obligations and the unique facts and circumstances involved in each particular agreement. Historically, payments made by the Company under these types of agreements have not had a material effect on its business, consolidated results of operations or financial condition.

Legal Proceedings

Securities Class Action Litigation

On March 12, 2020, a purported shareholder class action complaint, McDermid v. Inovio Pharmaceuticals, Inc. and J. Joseph Kim, was filed in the United States District Court for the Eastern District of Pennsylvania, naming the Company and its former President and Chief Executive Officer as defendants. The lawsuit alleged that the Company made materially false and misleading statements regarding its development of a vaccine for COVID-19 in its public disclosures in violation of certain federal securities laws. The plaintiffs sought unspecified monetary damages on behalf of the putative class and an award of costs and expenses, including reasonable attorneys’ fees. The plaintiffs’ complaint was later amended to include certain of the Company’s other officers as defendants. After additional motions were filed in the case, in June 2022 the parties negotiated an agreement in principle to settle the shareholder class action complaint. Under the settlement, the Company will pay $30.0 million in cash and $14.0 million in shares of its common stock to settle all outstanding claims. The Company's insurance carriers have paid the $30.0 million cash component of the settlement. On August 31, 2022, the court granted preliminary approval of the settlement. See Note 16 for events subsequent to December 31, 2022.

Shareholder Derivative Litigation

On April 20, 2020, a purported shareholder derivative complaint, Behesti v. Kim, et al., was filed in the United States District Court for the Eastern District of Pennsylvania, naming eight current and former directors of the Company as defendants. The lawsuit asserts state and federal claims and is based on the same alleged misstatements as the shareholder class

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action complaint described above. The lawsuit accuses the Company’s board of directors of failing to exercise reasonable and prudent supervision over the Company’s management, policies, practices, and internal controls. The plaintiff seeks unspecified monetary damages on behalf of the Company as well as governance reforms. On June 5, 2020, the court stayed the Beheshti action pending resolution of a forthcoming motion to dismiss the McDermid securities class action or until any party provides notice that they no longer consent to the stay. On June 12, 2020 and June 15, 2020, two additional shareholder derivative complaints were filed in the United States District Court for the Eastern District of Pennsylvania, captioned Isman v. Benito, et al. and Devarakonda et al. v Kim, et. al. The complaints assert substantially similar claims as the Beheshti action and name the Company’s current directors as defendants. The Devarakonda complaint also names one of the Company’s former directors as a defendant. On July 21, 2020, the court consolidated the three derivative cases under the caption In re Inovio Pharmaceuticals, Inc. Derivative Litigation. The consolidated action is stayed.

On July 7, 2020, a fourth shareholder derivative complaint, Fettig v. Kim et al., was filed in the United States District Court for the Eastern District of Pennsylvania, naming eight current and former directors of the Company as defendants. The complaint asserts substantially similar claims as those in the consolidated derivative action. On August 27, 2020, the Fettig action was consolidated with the other derivative cases, which remain stayed as explained above.

On March 28, 2022, a fifth shareholder derivative complaint, Schumacher v. Benito et al., was filed in the Delaware Court of Chancery, naming eight current and former directors as defendants. The complaint asserts substantially similar claims as those in the consolidated derivative action.On May 4, 2022, the Delaware Court of Chancery entered a stay of the litigation.

VGXI Litigation

On June 3, 2020, the Company filed a complaint in the Court of Common Pleas of Montgomery County, Pennsylvania against VGXI, Inc. and GeneOne Life Science, Inc., or GeneOne, and together with VGXI, Inc. collectively referred to as VGXI, alleging that VGXI had materially breached the Company’s supply agreement with them. The complaint seeks declaratory judgments, specific performance of the agreement, injunctive relief, an accounting, damages, attorneys’ fees, interest, costs and other relief from VGXI. On June 3, 2020, the Company filed a petition for preliminary injunction, which was denied on June 25, 2020. On June 26, 2020, the Company filed notice of appeal of the denial of the petition with the Pennsylvania Superior Court.

On July 7, 2020, VGXI filed an answer, new matter and counterclaims against the Company, alleging that the Company had breached the supply agreement, as well as misappropriation of trade secrets and unjust enrichment. The counterclaims seek injunctive relief, damages, attorneys’ fees, interest, costs and other relief from the Company. Also, on July 7, 2020, VGXI filed a third-party complaint against Ology Bioservices, Inc., a contract manufacturing organization that the Company had engaged to provide services similar to those that were being provided by VGXI. On July 27, 2020, the Company filed an answer to VGXI’s counterclaims, disputing the allegations and the claims raised in VGXI’s filing. On October 1, 2020, the Company filed a notice of discontinuance of appeal with the Pennsylvania Superior Court. A trial date for the litigation has not been set.

The Company intends to aggressively prosecute the claims set forth in its complaint against VGXI and to vigorously defend itself against VGXI’s counterclaims.

GeneOne Litigation

On December 7, 2020, GeneOne filed a complaint in the Court of Common Pleas of Montgomery County, Pennsylvania against the Company, alleging that the Company had breached the CELLECTRA Device License Agreement, or the Agreement, between the Company and GeneOne. The Company terminated the Agreement on October 9, 2020. The complaint asserts claims for breach of contract, declaratory judgment, unfair competition, and unjust enrichment. The complaint seeks injunctive relief, an accounting, damages, disgorgement of profits, attorneys’ fees, interest, and other relief from the Company. On January 29, 2021, the Company filed preliminary objections to the complaint. On August 23, 2021, the court overruled the Company’s preliminary objections to the complaint. On September 13, 2021, the Company filed an answer to the complaint, new matter, and counterclaims. The Company’s counterclaims allege that GeneOne breached the Agreement and assert claims for breach of contract and declaratory judgment.The counterclaims seek damages, interest, expenses, attorney’s fees, and costs.On October 18, 2021, GeneOne filed its answer to the Company’s counterclaims and new matter. On November 8, 2021, we filed our answer to GeneOne’s new matter. A trial date for this litigation has not been set.

The Company intends to aggressively prosecute the claims set forth in its counterclaims against GeneOne and to vigorously defend itself against the claims in GeneOne’s complaint.

Other Matters

From time to time, the Company may be involved in disputes, including litigation, relating to claims arising out of operations in the normal course of its business. Any of these claims could subject the Company to costly legal expenses and, while the Company generally believes that it has adequate insurance to cover many different types of liabilities, its insurance carriers may deny coverage or its policy limits may be inadequate to fully satisfy any damage awards or settlements. If this were to happen, the payment of any such awards could have a material adverse effect on the Company's consolidated results of

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operations and financial position. Additionally, any such claims, whether or not successful, could damage the Company's reputation and business. Except as described above, the Company is not a party to any legal proceedings, the adverse outcome of which, in management’s opinion, individually or in the aggregate, would be reasonably expected to have a material adverse effect on the Company’s consolidated results of operations or financial position.

12. Income Taxes

In accordance with the guidance pursuant to accounting for income taxes, a deferred tax asset or liability is determined based on the difference between the financial statement and tax basis of assets and liabilities as measured by the enacted tax rates which will be in effect when these differences reverse. The Company provides a valuation allowance against net deferred tax assets unless, based upon the available evidence, it is more likely than not that the deferred tax asset will be realized.

The components of pretax loss from operations are as follows:

Year Ended December 31,

There was no provision for or benefit from income taxes for the years ended December 31, 2022, 2021 and 2020.

The reconciliation of income taxes attributable to continuing operations computed at the statutory tax rates to income tax benefit, using a 21% statutory tax rate for December 31, 2022, 2021 and 2020, is as follows:

Year Ended December 31,

Nondeductible loss on extinguishment of debt — — 14,450,000

Deconsolidation of subsidiary — — 853,000

Change in tax rates (187,000) — —

$ — $ — $ —

Significant components of the Company’s deferred tax assets and liabilities as of December 31, 2022 and 2021 are shown below:

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As of December 31,

Deferred tax assets:

Deferred tax liabilities:

As of December 31, 2022, the Company had federal, California and Pennsylvania tax net operating loss (NOL) carryforwards of $920.6 million, $210.3 million and $89.6 million, respectively, net of the net operating losses that will expire due to IRC Section 382 limitations. The aggregate federal net operating losses generated in 2018 and after for the amount of $625.4 million will carryforward indefinitely and be available to offset up to 80% of future taxable income each year, subject to certain modifications made by the Coronavirus Aid, Relief, and Economic Security Act (CARES Act) enacted in 2020. The federal NOL carryforward began to expire in 2022, and the California and Pennsylvania NOL carryforwards will begin and have begun to expire in 2028 and 2022, respectively, unless previously utilized.

The Company also had Korean NOL carryforwards of $1.0 million as of December 31, 2022. The Korean NOLs are available to offset up to 60% of future taxable income and will begin to expire in 2030, unless previously utilized.

In addition, as of December 31, 2022, the Company had federal and state research and development (R&D) tax credit carryforwards of $40.5 million and $4.7 million, respectively. The federal tax credit carryforwards will begin to expire in 2029. The California research tax credits do not expire.

Based upon statute, federal and state losses and credits are expected to expire as follows (in millions):