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

You should read the following discussion and analysis of our financial condition and results of operations together with our consolidated financial statements and related notes appearing elsewhere in this Annual Report. In addition to historical information, this discussion and analysis contains forward-looking statements that involve risks, uncertainties and assumptions. Our actual results may differ materially from those anticipated in these forward-looking statements as a result of certain factors. We discuss factors that we believe could cause or contribute to these differences

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below and elsewhere in this report, including those set forth under Item 1A. “Risk Factors” and under “Cautionary Note Regarding Forward-Looking Statements” in this Annual Report.

In this Item 7, we discuss the results of operations for the years ended December 31, 2023 and 2022 and comparisons of our cash flows for the year ended December 31, 2023 to the year ended December 31, 2022. Discussion and analysis of our 2021 fiscal year, as well as the year-over-year comparison of our 2022 financial performance to 2021, are located in Part II, Item 7 - Management’s Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the fiscal year ended December 31, 2022, filed with the SEC on March 1, 2023.

Overview

We are a global, commercial-stage biopharmaceutical company dedicated to transforming the lives of patients and their families living with rare neuroendocrine diseases. We are focused on advancing our melanocortin-4 recptor (MC4R) agonists, including our lead asset, IMCIVREE® (setmelanotide), as a precision medicine designed to treat hyperphagia and severe obesity caused by MC4R pathway diseases. While obesity affects hundreds of millions of people worldwide, we are advancing developing therapies for a subset of individuals who have hyperphagia, a pathological hunger, and severe obesity due to an impaired MC4R pathway, which may be caused by traumatic injury or genetic variants. The MC4R pathway is an endocrine pathway in the brain that is responsible for regulating hunger, caloric intake and energy expenditure, which consequently affect body weight. IMCIVREE, an MC4R agonist for which we hold worldwide rights, is the first-ever therapy developed for patients with certain rare diseases that is approved or authorized in the United States, European Union (EU), Great Britain, Canada and other countries and regions. IMCIVREE is approved by the U.S. Food and Drug Administration (FDA) for chronic weight management in adult and pediatric patients 6 years of age and older with monogenic or syndromic obesity due to: (i) proopiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1) or leptin receptor (LEPR) deficiency as determined by an FDA-approved test demonstrating variants in POMC, PCSK1, or LEPR genes that are interpreted as pathogenic, likely pathogenic, or of uncertain significance (VUS); or (ii) Bardet-Biedl syndrome (BBS). The European Commission (EC) and Great Britain’s Medicines & Healthcare Products Regulatory Agency (MHRA) have authorized IMCIVREE for the treatment of obesity and the control of hunger associated with genetically confirmed BBS or genetically confirmed loss-of-function biallelic POMC, including PCSK1, deficiency or biallelic LEPR deficiency in adults and children 6 years of age and above. In addition to the United States and Canada, we have achieved market access for IMCIVREE for BBS or POMC and LEPR deficiencies, or both, in 14 countries outside the United States, and we continue to collaborate with authorities to achieve access in additional markets.

In addition to initial commercial efforts, we are advancing what we believe is the most comprehensive clinical research program ever initiated in MC4R pathway diseases, with multiple ongoing and planned clinical trials. Our MC4R pathway program is designed to expand the total number of patients who would benefit from setmelanotide therapy or our one of our new drug candidates, RM-718, which is designed to be a more selective MC4R agonist with weekly administration, or LB54640, an investigational oral small molecule MC4R agonist now in Phase 2 clinical trials. With setmelanotide, we have completed enrollment in our Phase 3 trial in patients with hypothalamic obesity. Our Phase 3 EMANATE trial, comprised of four independent substudies evaluating setmelanotide in genetically caused MC4R pathway diseases, and our Phase 2 DAYBREAK trial evaluating setmelanotide in additional genetic indications, are ongoing. With RM-718, we anticipate initiating Phase 1 in-human trials in the first half of 2024, including a multiple-ascending dose study in patients with hypothalamic obesity. In our recently completed Phase 3 pediatrics trial in 12 patients between the ages of 2 and younger than 6 with BBS or POMC or LEPR deficiency obesities, setmelanotide achieved the primary endpoint with a 3.04 mean reduction in BMI-Z score (a measure of body mass index deviations from what is considered normal) and 18.4 percent mean reduction in BMI. We are seeking regulatory approval in the United States and Europe to expand the label for IMCIVREE to treat patients as young as 2 with these diseases based on these data.

We are leveraging what we believe is the largest known DNA database focused on obesity - with almost 80,000 sequencing samples as of December 31, 2023 - to improve the understanding, diagnosis and care of people living with severe obesity due to certain variants in genes associated with the MC4R pathway. Our sequencing-based epidemiology estimates show that each of these genetically-defined MC4R pathway deficiencies are considered rare diseases, according to established definitions based on patient populations. Our epidemiology estimates are approximately 4,600 to 7,500 for U.S. patients in initial FDA-approved indications, including obesity due to biallelic POMC, PCSK1 or LEPR deficiencies,

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and BBS. We estimate the epidemiology for patients with hypothalamic obesity to be between 5,000 and 10,000 in the United States, based on our analysis of published literature. Our epidemiology estimates for the indications being studied in our Phase 3 EMANATE trial suggest that approximately 53,000 U.S. patients with one of these genetically driven obesities have the potential to respond well to setmelanotide. Similarly, our epidemiology estimates for patients with genetic indications who demonstrated an initial response in our Phase 2 DAYBREAK trial is approximately 65,300. All these patients face similar challenges as other patients with rare diseases, namely lack of awareness, resources, tests, tools and, especially, therapeutic options. We are developing setmelanotide to address additional patients with acquired hypothalamic obesity. In our Phase 2 trial evaluating setmelanotide as a treatment for hypothalamic obesity, as announced in November 2022, 16 of 18 patients achieved the primary endpoint with a body mass index (BMI) decrease greater than 5 percent on setmelanotide therapy, and we observed a 14.5 mean percent reduction in BMI across all patients. Fourteen of these patients transitioned from this Phase 2 trial into our open-label, long-term extension trial and they remain on therapy, as of November. 3, 2023. Twelve of these 14 patients had achieved a 25.5% reduction in mean BMI from baseline at one year on setmelanotide therapy. On February 22, 2024, we provided an update on progress of our pivotal, Phase 3 clinical trial evaluating setmelanotide in patients with acquired hypothalamic obesity. We completed enrollment in the Phase 3 clinical trial is designed to enroll 120 patients aged 4 years or older randomized 2:1 to setmelanotide therapy or placebo for a total of 60 weeks, including up to eight weeks for dose titration. The primary endpoint is the percent change in BMI after approximately 52 weeks on a therapeutic regimen of setmelanotide versus placebo. Key secondary endpoints include the proportion of patients who achieve ≥5% reduction in BMI from baseline in adults (≥18) or BMI Z-score reduction of ≥0.2 from baseline in pediatrics after approximately 52 weeks on a therapeutic regimen of compared with placebo, and mean change in the weekly average of the daily most hunger score in patients ≥12 years from baseline after approximately 52 weeks on a therapeutic regimen of setmelanotide versus placebo. We expect to report top-line study results in the first half of 2025.

Up until recently, our operations have been limited primarily to conducting research and development activities for setmelanotide. To date, we have not generated sufficient cash flow from product sales and have financed our operations primarily through the proceeds received from the sales of common and preferred stock, royalty interest financing, asset sales, as well as capital contributions from the former parent company, Rhythm Holdings LLC. From August 2015 through August 2017, we raised aggregate net proceeds of $80.8 million through our issuance of series A preferred stock. Since our initial public offering, or IPO, on October 10, 2017 and our underwritten follow-on offerings through October 2022, we have raised aggregate net proceeds of approximately $791.5 million through the issuance of our common stock after deducting underwriting discounts, commissions and offering related transaction costs. We also received $100.0 million from the sale of our Rare Pediatric Disease Priority Review Voucher, or PRV, to Alexion Pharmaceuticals, Inc. in February 2021. In June 2022, we entered into the Revenue Interest Financing Agreement (“RIFA”), with entities managed by HealthCare Royalty Partners, collectively referred to as the Investors, and through December 31, 2023 have received cumulative proceeds of $96.7 million, net of certain transaction costs.

IMCIVREE became commercially available to patients 6 years of age and older with obesity due to POMC, PCSK1 or LEPR deficiency in the U.S. in the first quarter of 2021 and patients 6 years of age and older with obesity due to BBS during June 2022. Following marketing authorizations in the EU and Great Britain, we are pursuing a country-by-country strategy to establish market access and reimbursement for IMCIVREE in several countries. During March 2022, we treated the first patients with IMCIVREE in France under the paid early access program and we treated the first patients with IMCIVREE in Germany during June 2022. We expect to continue to fund our operations through the sale of equity, debt financings or other sources. We have built our own marketing and commercial sales infrastructure in the United States and are in the process of building a similar infrastructure in several European markets and the United Kingdom. We may enter into collaborations with other parties for certain markets outside the United States. However, we may be unable to raise additional funds or enter into such other arrangements when needed on favorable terms, or at all. If we fail to raise capital or enter into such other arrangements as, and when, needed, we may have to significantly delay, scale back or discontinue the development or commercialization of setmelanotide.

As of December 31, 2023, we had an accumulated deficit of $894.7 million. Our net losses were $184.7 million and $181.1 million for the years ended December 31, 2023 and 2022, respectively. We expect to continue to incur

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significant expenses and increasing operating losses over the foreseeable future. We expect our expenses will increase substantially in connection with our ongoing activities, as we:

● continue to operate as a public company.

As of December 31, 2023, our cash and cash equivalents and short-term investments were approximately $275.8 million. We expect that our cash and cash equivalents and short-term investments as of December 31, 2023, will enable us to fund our operating expenses into the second half of 2025.

Corporate Background

We are a Delaware corporation organized in February 2013 under the name Rhythm Metabolic, Inc., and as of October 2015, under the name Rhythm Pharmaceuticals, Inc.

Financial Operations Overview

Revenue

To date, we have generated approximately $97.0 million of revenue from product sales. Our lead product candidate, IMCIVREE, was approved by the FDA in November 2020 for chronic weight management in adult and pediatric patients six years of age and older with obesity due to POMC, PCSK1 or LEPR deficiency confirmed by genetic testing. IMCIVREE became commercially available in the United States in the first quarter of 2021. We recorded our first sales of IMCIVREE in the United States in March 2021 and we made our first sales in France in March 2022 under the paid early access program. IMCIVREE was approval by the FDA and the EC in adult and pediatric patients six years of age and older with obesity due to BBS in June and September 2022, respectively. Following these approvals for BBS, sales of IMCIVREE have grown, and we expect will continue to grow as we identify and treat more patients with this disease and obtain reimbursement throughout the international markets in which we operate.

Cost of sales

All of our inventory of IMCIVREE produced prior to FDA approval is available for commercial or clinical use. Most of the manufacturing costs have been recorded as research and development expenses in prior periods. Accordingly, the costs for IMCIVREE included in our cost of sales for the year ended December 31, 2022 were insignificant. Cost of sales increased in 2023 as we sold inventory that was produced after we began capitalizing manufacturing costs for IMCIVREE commercial inventory and experienced increased enrollment in our patient assistance programs.

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Research and development expenses

Research and development expenses consist primarily of costs incurred for our research activities, including our drug discovery and genetic sequencing efforts, and the clinical development of setmelanotide, which include:

● the cost of genetic sequencing of potential patients in clinical studies;

We expense research and development costs to operations as incurred. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are recorded as prepaid expenses. The capitalized amounts are expensed as the related goods are delivered or the services are performed.

The following table summarizes our current research and development expenses:

December 31,

Research and development summary 2023 2022

We are unable to predict the duration and costs of the current or future clinical trials of our product candidates. The duration, costs, and timing of clinical trials and development of setmelanotide, RM-718, LB54640, and a potential therapeutic product candidate for CHI will depend on a variety of factors, including:

● the rate of enrollment in clinical trials;

● changes in regulatory requirements;

● changes in clinical trial design; and

● the timing and receipt of any regulatory approvals.

A change in the outcome of any of these variables with respect to the development of our product candidates would significantly change the costs and timing associated with its development and potential commercialization.

Research and development activities are central to our business model. Product candidates in later stages of clinical development generally have higher development costs than those in earlier stages of clinical development,

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primarily due to the increased size and duration of later-stage clinical trials. We expect research and development costs to increase significantly for the foreseeable future as our setmelanotide and other development programs progress. However, we do not believe that it is possible at this time to accurately project total program-specific expenses to commercialization and there can be no guarantee that we can meet the funding needs associated with these expenses.

Selling, general and administrative expenses

Selling expenses consist of professional fees related to preparation for the commercialization of setmelanotide as well as salaries and related benefits for commercial employees, including stock-based compensation. As we further implement and execute our commercialization plans to market setmelanotide in new territories and as we explore new collaborations to develop and commercialize setmelanotide, we anticipate that these expenses will materially increase.

General and administrative expenses consist primarily of salaries and other related costs, including stock-based compensation, relating to our full-time employees not involved in R&D or commercial activities. Other significant costs include rent, legal fees relating to patent and corporate matters and fees for accounting and consulting services.

The following table summarizes our current selling, general and administrative expenses.

December 31,

Selling, general and administrative summary 2023 2022

Selling, general and administrative expense $ 117,532 $ 92,032

We anticipate that our selling, general and administrative expenses will increase in the future to support continued and expanding commercialization efforts for IMCIVREE in the United States and the European Union as well as increased costs of operating as a global commercial stage biopharmaceutical public company. These increases will likely include increased costs related to the hiring of additional personnel and fees to outside consultants, lawyers and accountants, compliance with local rules and regulations in the United States and foreign jurisdictions, exchange listing and SEC expenses, insurance and investor relations costs, among other expenses.

Critical Accounting Policies and Estimates

Our management's discussion and analysis of our financial condition and results of operations are based on our financial statements, which we have prepared in accordance with accounting principles generally accepted in the United States, or GAAP. The preparation of these financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements, as well as the reported amounts of revenues and expenses during the reporting periods. These items are monitored and analyzed by us for changes in facts and circumstances on an ongoing basis, and material changes in these estimates could occur in the future. We base our estimates on historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

While our significant accounting policies are described in more detail in the notes to our consolidated financial statements included elsewhere in this Annual Report, we believe that the following accounting policies are the most critical to aid in fully understanding and evaluating our financial condition and results of operations.

Accrued research and development expenses

As part of the process of preparing our financial statements, we are required to estimate the value associated with goods and services received in the period in connection with research and development activities. This process involves reviewing quotations and contracts, identifying services that have been performed on our behalf and estimating the level of service performed and the associated cost incurred for the service when we have not yet been invoiced or otherwise notified of the actual cost, or alternatively, the deferral of amounts paid for goods or services to be incurred in the future.

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The majority of our service providers invoice us monthly in arrears for services performed or when contractual milestones are met. We make estimates of our accrued expenses or prepaid expenses as of each balance sheet date in our financial statements based on facts and circumstances known to us at the time those financial statements are prepared. We periodically confirm the accuracy of our estimates with the service providers and make adjustments if necessary. The significant estimates in our accrued research and development expenses include fees paid to CROs, CMOs and consultants in connection with research and development activities.

We accrue our expenses related to CROs, CMOs and consultants based on our estimates of the services received and efforts expended pursuant to quotes and contracts with CROs, CMOs and consultants that conduct research and development and manufacturing on our behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. The allocation of CRO upfront expenses for both clinical trials and preclinical studies generally tracks actual work activity. However, there may be instances in which payments made to our vendors will exceed the level of services provided and result in a prepayment of the research and development expense. In accruing service fees delivered over a period of time, we estimate the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from our estimate, we adjust accrued or prepaid expense accordingly. Although we do not expect our estimates to be materially different from amounts actually incurred, if our estimates of the status and timing of services performed differ from the actual status and timing of services performed, it could result in us reporting amounts that are too high or too low in any particular period. To date, there have been no material differences between our estimates of such expenses and the amounts actually incurred.

Stock-based compensation

We maintain the Rhythm Pharmaceuticals, Inc. 2017 Equity Incentive Plan, (the “2017 Plan”) which provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, performance units, restricted stock awards, restricted stock units and stock grants to employees, consultants, advisors and directors, as determined by the board of directors. As of December 31, 2023, we had reserved 12,669,203 shares of common stock under the 2017 Plan. Shares of common stock issued pursuant to awards are generally issued from authorized but unissued shares. The 2017 Plan provides that the exercise price of incentive stock options cannot be less than 100% of the fair market value of the common stock on the date of the award for participants who own less than 10% of the total combined voting power of stock, and not less than 110% for participants who own more than 10% of the voting power. Awards granted under the 2017 Plan will vest over periods as determined by our Compensation Committee and approved by our board of directors.

On February 9, 2022, our board of directors adopted the Rhythm Pharmaceuticals, Inc. 2022 Employment Inducement Plan (the “2022 Inducement Plan”), which became effective on such date without stockholder approval pursuant to Rule 5635(c)(4) of the Nasdaq Stock Market LLC listing rules (“Rule 5635(c)(4)”). The 2022 Inducement Plan provides for the grant of non-qualified stock options, stock appreciation rights, performance units, restricted stock awards, restricted stock units and stock grants. In accordance with Rule 5635(c)(4), awards under the 2022 Inducement Plan may only be made to a newly hired employee who has not previously been a member of our board of directors, or an employee who is being rehired following a bona fide period of non-employment by the Company or a subsidiary, as a material inducement to the employee’s entering into employment with the Company or its subsidiary. An aggregate of 1,000,000 shares of our common stock have been reserved for issuance under the 2022 Inducement Plan.

The exercise price of stock options granted under the 2022 Inducement Plan will not be less than the fair market value of a share of our common stock on the grant date. Other terms of awards, including vesting requirements, are determined by our board of directors and are subject to the provisions of the 2022 Inducement Plan. Stock options granted to employees generally vest over a four-year period but may be granted with different vesting terms. Certain options may provide for accelerated vesting in the event of a change in control. Stock options granted under the 2022 Inducement Plan expire no more than 10 years from the date of grant. As of December 31, 2023, there were 526,177 stock option awards outstanding, 233,719 restricted stock unit awards outstanding and 179,925 shares of common stock available for future grant under the 2022 Inducement Plan.

We estimate the fair value of our stock option awards to employees and non-employees using the Black-Scholes option-pricing model, which requires the input of subjective assumptions, including (a) the expected volatility of our stock,

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(b) the expected term of the award, (c) the risk-free interest rate, and (d) expected dividends. Due to the lack of a public market for the trading of our common stock and a lack of company-specific historical and implied volatility data, we previously based our estimate of expected volatility on the historical volatility of a group of companies in the pharmaceutical and biotechnology industries in a similar stage of development as us and that are publicly traded. For these analyses, we selected companies with comparable characteristics to ours including enterprise value, risk profiles and with historical share price information sufficient to meet the expected life of the stock-based awards. We computed the historical volatility data using the daily closing prices for the selected companies' shares during the equivalent period of the calculated expected term of our stock-based awards. We estimate volatility by using a blend of our stock price history for the length of time we have market data for our stock and the historical volatility of similar public companies for the expected term of each grant. We will continue to apply this process until a sufficient amount of historical information regarding the volatility of our own stock price becomes available.

We have estimated the expected life of our employee stock options using the "simplified" method, whereby, the expected life equals the average of the vesting term and the original contractual term of the option. The risk-free interest rates for periods within the expected life of the option are based on the U.S. Treasury yield curve in effect during the period the options were granted. We have elected to account for forfeitures as they occur. Upon adopting Accounting Standards Update 2018-07, Improvements to Nonemployee Share-Based Payment Accounting (Topic 718) on July 1, 2018, we elected that unsettled equity-classified awards to nonemployees for which a measurement date has not been established be measured using the adoption date fair value.

Income taxes

We account for uncertain tax positions in accordance with the provisions of Accounting Standards Codification, or ASC, Topic 740, Accounting for Income Taxes, or ASC 740. When uncertain tax positions exist, we recognize the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. As of December 31, 2023, we did not have any uncertain tax positions.

Income taxes are recorded in accordance with ASC 740, which provides for deferred taxes using an asset and liability approach. We recognize deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements or tax returns. We determine our deferred tax assets and liabilities based on differences between financial reporting and tax bases of assets and liabilities, which are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. Valuation allowances are provided, if based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized.

As of December 31, 2023, we had net operating loss carryforwards to reduce federal and state incomes taxes of approximately $555.6 million and $598.0 million, respectively. If not utilized, these carryforwards begin to expire in 2033. Of the federal net operating loss carryforwards at December 31, 2023, $482.4 million can be carried forward indefinitely. In addition, as of December 31, 2023, we had foreign net operating loss carryforwards of approximately $1.3 million which have an indefinite carryforward period. At December 31, 2023, we also had available research and development tax credits for federal and state income tax purposes of approximately $13.1 million and $3.8 million, respectively. Additionally, as of December 31, 2023, we had federal orphan drug credits related to qualifying research of $25.5 million. These tax credit carryforwards begin to expire in 2033 for federal purposes and 2028 for state purposes.

Utilization of the net operating loss and tax credit carryforwards may be subject to a substantial annual limitation due to ownership change limitations that have occurred previously or that could occur in the future, as provided by Section 382 of the Internal Revenue Code of 1986, as amended, or the Code, or Section 382, as well as similar state provisions and other provisions of the Code. Ownership changes may limit the amount of net operating losses and tax credit carryforwards that can be utilized annually to offset future taxable income and tax, respectively. In general, an ownership change, as defined by Section 382, occurs when there is a greater than 50% change in the ownership of stock among certain 5% shareholders over a three-year period.

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Results of Operations

Comparison of years ended December 31, 2023 and 2022

The following table summarizes our results of operations for the years ended December 31, 2023 and 2022, together with the changes in those items in dollars and as a percentage:

Year Ended

December 31, Change

(in thousands)

Statement of Operations Data:

Costs and expenses:

Provision for income taxes 564 — 564 100 %

Product revenue, net increased by $60.5 million to $77.4 million in 2023 from $16.9 million in 2022 an increase of 359%. We expect our sales of IMCIVREE to continue to increase following the FDA approval for the treatment of patients with BBS in the United States in June 2022 and ten other countries since then. For the years ended December 31, 2023 and 2022, a substantial amount of our product revenue, or 81% and 89%, respectively, was generated from sales of our product to patients in the United States. Product revenue for the year ended December 31, 2023 was affected by a single state Medicaid program change to documentation requirements for reimbursement that resulted in some patients transitioning to the Company’s free-drug bridging program during the fourth quarter of 2023.

License revenue. We did not recognize license revenue in 2023, compared to $6.8 million of license revenue in 2022 related entirely to the RareStone license agreement. We entered into a license agreement with RareStone in December 2021 and completed our activities required to transfer the license to RareStone during the second quarter of 2022, which resulted in the recognition of the license revenue.

Cost of sales. Cost of sales increased by $7.2 million to $9.3 million in 2023 from $2.1 million in 2022, an increase of 336%, which was driven by a similar increase in revenue in 2023. Cost of sales is composed of royalty expense due to Ipsen Pharma S.A.S., or Ipsen, on our net product sales and the amortization of our capitalized sales-based milestone payment made to Ipsen, upon our first commercial sale in the U.S. and EU, the cost of product, as well as costs associated with our patient assistance programs. Specifically, the $7.2 million increase in cost of sales in 2023 was due to $3.0 million of additional royalties due to our growth in sales, $3.7 million attributed to increased product cost associated with higher sales volume and $0.4 million of amortization of our capitalized sales-based milestone payment, which began to accrue in the second half of 2022. We expect cost of sales as a percentage of product revenue, net to continue to be in a range of 10% to 12% in foreseeable future.

Research and development expense. Research and development expense increased by $26.3 million to $135.0 million in 2023 from $108.6 million in 2022, an increase of 24%. The increase was primarily due to the following:

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Selling, general and administrative expense. Selling, general and administrative expense increased by $25.5 million to $117.5 million in 2023 from $92.0 million in 2022, an increase of 28%. The increase was primarily due to the following:

The above increases were partially offset by:

Other (expense) income, net. Other (expense) income, net increased by $2.2 million to $0.2 million in 2023, a increase of 112%. The net increase was primarily due to the following:

These increases were slightly offset by:

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Liquidity and Capital Resources

As of December 31, 2023, our cash and cash equivalents and short-term investments were approximately $275.8 million.

Cash flows

The following table provides information regarding our cash flows for the years ended December 31, 2023 and 2022:

Year Ended December 31,

(in thousands)

Net cash (used in) provided by:

Effect of exchange rates on cash (142) —

Net cash used in operating activities

The use of cash in all periods resulted primarily from our net losses, adjusted for non-cash charges and changes in components of working capital.

Net cash used in operating activities was $136.2 million for the year ended December 31, 2023, and consisted primarily of a net loss of $184.7 million adjusted for non-cash items of $38.0 million, which consisted of stock-based compensation, depreciation and amortization, non-cash rent expense, accretion and amortization of our short-term investments and the change in the fair value of our embedded derivative liability. Our net loss also includes $5.7 million of acquired In-Process Research and Development (IPR&D) assets, which are classified as investing activities. The change in operating assets and liabilities reflected a total net source of cash of approximately $4.8 million primarily driven by a net increase in accounts payable and accrued expenses of $14.8 million, decreases in long term assets of $1.7 million and decreases in prepaid expenses and other current assets of $2.7 million. The net cash sources described above were partially offset by net cash uses from increases in accounts receivable and inventory totaling $14.4 million, based on the ongoing growth in the business.

Net cash used in operating activities was $173.4 million for the year ended December 31, 2022, and consisted primarily of a net loss of $156.0 million adjusted for non-cash items, which consisted of stock-based compensation, depreciation and amortization, non-cash rent expense, the change in the fair value of our embedded derrivative liability, and the impairment of RareStone equity. The change in operating assets and liabilities reflected a total use of cash of approximately $17.4 million primarily driven by an increase of $12.3 million in accounts receivable, inventory, prepaid expenses, other current and a decrease in deferred revenue of $6.6 million. The net cash uses were partially offset by an increase in accounts payable and accrued expenses of $1.5 million due to the timing of payments.

Net cash provided by (used in) investing activities

Net cash used in investing activities was $5.7 million for the year ended December 31, 2023 which relates primarily to cash used to purchase Xinvento’s IPR&D assets for $5.7 million in February 2023. Our gross purchases of short-term investments of $354.9 million were generally offset by gross proceeds from maturities of short-term investments of $355.0 million.

Net cash provided by investing activities was $28.0 million for the year ended December 31, 2022 which relates to the proceeds from short-term investments of $32.2 million, partially offset by $0.3 million related to the purchase of property plant and equipment and $4.0 million for the acquisition of an intangible asset.

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Net cash provided by financing activities

Net cash provided by financing activities was $74.4 million for the year ended December 31, 2023, which is composed of net proceeds of $48.9 million from the issuance of common stock in August 2023, net proceeds of $24.4 million from the final investment tranche of our deferred royalty obligation and $8.5 million of cash proceeds from the exercise of stock options and the issuance of common stock from our 2017 Employee Stock Purchase Plan, or the ESPP. These proceeds were partially offset by $7.4 million of repayments of our deferred royalty obligation.

Net cash provided by financing activities was $213.8 million for the year ended December 31, 2022, which represents the net proceeds of $131.1 million from our common stock offering in September 2022, $72.3 million of aggregate proceeds, net of issuance costs from the RIFA, and $10.4 million of cash proceeds from the exercise of stock options and the issuance of common stock from our ESPP.

Revenue Interest Financing Agreement

On June 16, 2022, we entered into the RIFA with HealthCare Royalty, for a total investment amount of up to $100 million. In exchange for the total investment amount to be received by Rhythm, HealthCare Royalty will receive a tiered royalty based on global net product sales generated by IMCIVREE. For additional information, see Note 11, “Long-term Obligations” to the consolidated financial statements included elsewhere in this Annual Report.

Funding requirements

We expect our expenses to increase in connection with our ongoing activities, particularly as we continue the clinical development of and seek marketing approval for setmelanotide for future indications and build out our global organization. In addition, we expect to incur significant commercialization expenses related to product sales, marketing, manufacturing and distribution to the extent that such sales, marketing and distribution are not the responsibility of potential collaborators. We also expect to incur additional costs associated with operating as a public company.

We expect that our existing cash and cash equivalents and short-term investments will be sufficient to fund our operations into the second half of 2025. Our cash and cash equivalents are maintained at financial institutions in amounts that exceed federally-insured limits. In the event of failure of any of the financial institutions where we maintain our cash and cash equivalents, there can be no assurance that we will be able to access uninsured funds in a timely manner or at all.

We may need to obtain substantial additional funding in connection with our research and development activities and any continuing operations thereafter. If we are unable to raise capital when needed or on favorable terms, we would be forced to delay, reduce or eliminate our research and development programs or future commercialization efforts.

Our future capital requirements will depend on many factors, including:

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Although IMCIVREE has been approved by the FDA in certain indications, and became commercially available in the first quarter of 2021, IMCIVREE may not achieve commercial success. In addition, developing our setmelanotide program is a time-consuming, expensive and uncertain process that may take years to complete, and we may never generate the necessary data or results required to obtain future marketing approvals and achieve product sales. Accordingly, we will need to continue to rely on additional financing to achieve our business objectives. Adequate additional financing may not be available to us on acceptable terms, or at all.

Further, the global economy, including credit and financial markets, has recently experienced extreme volatility and disruptions, including severely diminished liquidity and credit availability, rising interest and inflation rates, declines in consumer confidence, declines in economic growth, increases in unemployment rates and uncertainty about economic stability. All of these factors could impact our liquidity and future funding requirements, including but not limited to our ability to raise additional capital when needed on acceptable terms, if at all. The duration of this economic slowdown is uncertain and the impact on our business is difficult to predict. See “Risk Factors— Unfavorable global political or economic conditions could adversely affect our business, financial condition or results of operations.”

Until such time, if ever, as we can generate substantial product revenues, we expect to finance our cash needs through a combination of equity offerings, debt financings, collaborations, strategic alliances and licensing arrangements.

To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our stockholders will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our common stockholders. Debt financing, if available, involves agreements that include covenants limiting or restricting our ability to take specific actions, such as incurring additional debt, making capital expenditures or declaring dividends.

If we raise funds through additional collaborations, strategic alliances or licensing arrangements with third parties, we may have to relinquish valuable rights to our setmelanotide program on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings when needed, we may be required to delay, limit, reduce or terminate our product development or future commercialization efforts or grant rights to develop and market our setmelanotide program that we would otherwise prefer to develop and market ourselves.

ATM

On November 2, 2021, we entered into a Sales Agreement with Cowen and Company, LLC (“Cowen”), pursuant to which we may issue and sell shares of its common stock, having an aggregate offering price of up to $100.0 million, from time to time through an “at the market” equity offering program under which Cowen acts as sales agent (the “ATM Program”). Between August 10, 2023 and August 21, 2023, we sold approximately two million shares of our common stock in the ATM Program for net proceeds of approximately $48.9 million.

On September 19, 2022, we completed a public offering of 4,800,000 shares of common stock at a price to the public of $26.00 per share. We received $116,887 in net proceeds after deducting underwriting discounts, commissions and offering expenses. In addition, we granted the underwriters a 30-day option to purchase up to an additional 720,000

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shares of its common stock at the price to the public, less underwriting discounts and commissions. On October 18, 2022, we completed the sale of an additional 580,000 shares of common stock at a price to the public of $26.00 per share pursuant to the partial exercise of the underwriters’ option to purchase additional shares, for aggregate net proceeds of approximately $14,175, after deducting underwriting discounts, commissions and offering expenses.

Contractual obligations

We enter into agreements in the normal course of business with CROs and CMOs for clinical trials and clinical supply manufacturing and with vendors for clinical research studies and other services and products for operating purposes. We do not classify these as contractual obligations where the contracts are cancelable at any time by us, generally upon 30 days' prior written notice to the vendor.

Milestone and royalty payments associated with our license agreements with Ipsen, Camurus, Takeda, and LG Chem, have not been included as contractual obligations as we cannot reasonably estimate if or when they will occur. Under the terms of the Ipsen license agreement, assuming that setmelanotide is successfully developed, receives regulatory approval and is commercialized, Ipsen may receive aggregate payments of up to $40.0 million upon the achievement of certain development and commercial milestones under the license agreement and royalties on future product sales and at December 31, 2023 there were $27.0 million of remaining milestones that may be achieved and due to Ipsen at a future date. During 2022, we paid Ipsen a $4.0 million milestone upon our first commercial sale of IMCIVREE in Europe. We did not make additional milestone payments to Ipsen during 2023. In the event that we enter into a sublicense agreement, we will make payments to Ipsen, depending on the date of the sublicense agreement, ranging from 10% to 20% of all revenues actually received under the sublicense agreement.

Under the terms of the Camurus license agreement, assuming that the weekly formulation of setmelanotide is successfully developed, receives regulatory approval and is commercialized, Camurus may receive aggregate payments of up to $64.8 million upon the achievement of certain development and commercial milestones under the license agreement and royalties on future product sales. As of December 31, 2023, there were $62.5 million of remaining milestones that may be achieved and for which Camurus would receive payment at a future date. We paid Camurus a $1.0 million milestone in 2022 upon the achievement of a development milestone. We did not make any milestone payments to Camurus during 2023. The majority of the aggregate payments under the Camurus license agreement are for milestones that may be achieved no earlier than first commercial sale of this weekly formulation of setmelanotide.

Under the terms of the Takeda license agreement, assuming that RM-853, is successfully developed, receives regulatory approval and is commercialized, Takeda may receive aggregate payments of up to $140.0 million upon the achievement of certain development and commercial milestones under the license agreement and royalties on future product sales. The majority of the aggregate payments under the Takeda license agreement are for milestones that may be achieved no earlier than first commercial sale of the RM-853. We have notified Takeda that we have halted development activities related to RM-853. We did not make milestone payments to Takeda during 2023.

Under the terms of the LG Chem license agreement, we have paid LG Chem $40 million in cash and issued shares of our common stock with an aggregate value of $20 million. We have also agreed to pay LG Chem up to $205 million in cash upon achieving various regulatory and sales milestones based on net sales of LB54640. In addition and subject to the completion of Phase 2 development of LB54640, the Company has agreed to pay LGC royalties of between low-to-mid single digit percent of net revenues from its MC4R portfolio, including LB54640, commencing in 2029 and dependent upon achievement of various regulatory and indication approvals, and subject to customary deductions and anti-stacking. Royalties may further increase to a low double digit percent royalty, though such royalty would only be applicable on net sales of LB54640 in a region if LB54640 is covered by a composition of matter or method of use patent controlled by LGC in such region and the Company’s MC4R portfolio is not covered by any composition of matter or method of use patents controlled by the Company in such region. Such increased rate would only apply on net sales of LB54640 for the limited remainder of the royalty term in the relevant region. We entered into this agreement in 2024 and have not yet made any milestone payments.

Based on our current development plans as of December 31, 2023, we do not expect to make any milestone payments to third parties, during the next 12 months from the filing of this Annual Report. Milestones generally become due and payable upon achievement of such milestones or sales. When the achievement of these milestones or

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sales have not occurred, such contingencies are not recorded in our financial statements and are excluded from the table below.

In August 2018, we amended our existing Lease Agreement for our head office facility in Boston, Massachusetts. The new lease term commenced in May 2019 and has a term of six years with a five-year renewal option to extend the lease. The new lease includes approximately 13,600 square feet of office space.

Recent Accounting Pronouncements

For a discussion of pending and recently adopted accounting pronouncements, see Note 2 to our audited consolidated financial statements included elsewhere in this Annual Report.

Item 7A. Quantitative and Qualitative Disclosures About Market 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, particularly because our investments, including cash equivalents, are in the form, or may be in the form of, money market funds or marketable securities and are or may be invested in U.S. Treasury and U.S. government agency obligations. Due to the short-term maturities and low risk profiles of our investments, an immediate 100 basis point change in interest rates would not have a material effect on the fair market value of our investments.

We are not materially exposed to market risk related to changes in foreign currency exchange rates.

Item 8. Financial Statements and Supplementary Data

See the consolidated financial statements filed as part of this Annual Report as listed under Item 15 below.

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosures

Not Applicable.

Item 9A. Controls and Procedures

Limitations on Effectiveness of Controls and Procedures

We maintain disclosure controls and procedures (as that term is defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act). In designing and evaluating our disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives. In addition, the design of disclosure controls and procedures must reflect the fact that there are resource constraints and that management is required to apply judgment in evaluating the benefits of possible controls and procedures relative to their costs.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our principal executive officer and principal financial officer, has evaluated the effectiveness of our disclosure controls and procedures (as defined in Rules 13a- 15(e) and 15d- 15(e) under the Exchange Act), as of the end of the period covered by this Annual Report. Based on such evaluation, our principal executive officer and principal financial officer have concluded that as of December 31, 2023, our disclosure controls and procedures were not effective at the reasonable assurance level due to the material weakness in internal control over financial reporting described below.

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Management’s Annual Report on Internal Control over Financial Reporting

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) of the Exchange Act). Our management assessed the effectiveness of our internal control over financial reporting as of December 31, 2023. In making this assessment, it used the criteria established in Internal Control—Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

Based upon this evaluation and the material weakness identified below, our management concluded that our internal control over financial reporting was not effective as of December 31, 2023.

Material Weakness in Internal Control

We identified a material weakness in internal control related to ineffective information technology general controls, or ITGCs, in the areas of user access and program change management over our key accounting and reporting information technology, or IT, system. As a result, the related business process controls (IT application controls and IT-dependent manual controls) that are dependent on the ineffective ITGCs, or that use data produced from the system impacted by the ineffective ITGCs, were also ineffective.

The material weakness identified above did not result in any material misstatements in our financial statements or disclosures, and there were no changes to previously released financial results. Our management concluded that the consolidated financial statements included in this Annual Report on Form 10-K, present fairly, in all material respects, our financial position, results of operations, and cash flows for the periods presented in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP.

The Company’s independent registered public accounting firm, Ernst & Young LLP, has audited the effectiveness of the Company’s internal control over financial reporting as of December 31, 2023. Their report is set forth herein under the heading “Report of Independent Registered Public Accounting Firm” below.

Remediation of Material Weakness

Our management is committed to maintaining a strong internal control environment. In response to the identified material weakness above, management intends to take comprehensive actions to remediate the material weakness in internal control over financial reporting.

The remediation actions include: (i) developing and implementing additional training and awareness programs addressing ITGCs and policies, including educating control owners concerning the principles and requirements of each control, with a focus on user access; (ii) increasing the extent of oversight and verification checks included in the operation of user access and program change management controls and processes; (iii) deploying additional tools to support administration of user access and program change management; and (iv) enhancing quarterly management reporting on the remediation measures to the Audit Committee of the Board of Directors.

We believe that these actions, when fully implemented, will remediate the material weakness. The weakness will not be considered remediated, however, until the applicable controls operate for a sufficient period of time and management has concluded, through testing, that these controls are operating effectively. We may also conclude that additional measures may be required to remediate the material weakness in our internal control over financial reporting, which may necessitate additional implementation and evaluation time. We will continue to assess the effectiveness of our internal control over financial reporting and take steps to remediate the known material weakness expeditiously.

Changes in Internal Control Over Financial Reporting

Except as described above, there were no changes in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d 15(f) under the Exchange Act) that occurred during the fourth quarter of 2023 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of Rhythm Pharmaceuticals, Inc.

Opinion on Internal Control Over Financial Reporting

We have audited Rhythm Pharmaceuticals, Inc.’s internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework) (the COSO criteria). In our opinion, because of the effect of the material weakness described below on the achievement of the objectives of the control criteria, Rhythm Pharmaceuticals, Inc. (the Company) has not maintained effective internal control over financial reporting as of December 31, 2023, based on the COSO criteria.

A material weakness is a deficiency, or combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of the company’s annual or interim financial statements will not be prevented or detected on a timely basis. The following material weakness has been identified and included in management’s assessment. Management has identified a material weakness in internal control related to ineffective information technology general controls, or ITGCs, in the areas of user access and program change management over its key accounting and reporting information technology, or IT, system. As a result, the related business process controls (IT application controls and IT-dependent manual controls) that are dependent on the ineffective ITGCs, or that use data produced from the system impacted by the ineffective ITGCs, were also ineffective.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets of the Company as of December 31, 2023 and 2022, the related consolidated statements of operations and comprehensive loss, stockholders’ equity and cash flows for each of the three years in the period ended December 31, 2023, and the related notes. The material weakness was considered in determining the nature, timing and extent of audit tests applied in our audit of the 2023 consolidated financial statements, and this report does not affect our report dated February 29, 2024, which expressed an unqualified opinion thereon.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting included in the accompanying Management’s Annual Report on Internal Control over Financial Reporting. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. 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 U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects.

Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control Over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions

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are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Ernst & Young LLP

Boston, Massachusetts

February 29, 2024

Item 9B. Other Information

a)Disclosure in lieu of reporting on a Current Report on Form 8-K.

None.

b)Insider Trading Arrangements and Policies.

During the three months ended December 31, 2023, no director or officer of the Company adopted or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 tradingarrangement,” as each term is defined in Item 408(a) of Regulation S-K.

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Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections.

Not applicable.

PART III

Item 10. Directors, Executive Officers and Corporate Governance

We have adopted a Code of Business Conduct and Ethics for all of our directors, officers and employees, including our principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. We have posted a current copy of our Code of Business Conduct and Ethics on our website at www.rhythmtx.com in the “Investors & Media” section under “Corporate Governance.” We intend to disclose on our website any amendments to, or waivers from, our Code of Business Conduct and Ethics that are required to be disclosed pursuant to the rules of the SEC, as well as Nasdaq’s requirement to disclose waivers with respect to directors and executive officers. The information contained on our website is not considered part of, or incorporated by reference into, this Annual Report or any other filing that we make with the SEC.

The remaining information required under this item is incorporated herein by reference to our definitive proxy statement for our 2024 annual meeting of stockholders, which proxy statement will be filed with the Securities and Exchange Commission not later than 120 days after the close of our fiscal year ended December 31, 2023.

Item 11. Executive Compensation

The information required under this item is incorporated herein by reference to our definitive proxy statement for our 2024 annual meeting of stockholders, which proxy statement will be filed with the Securities and Exchange commission not later than 120 days after the close of our fiscal year ended December 31, 2023.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Equity Compensation Plan Information

The following table provides information as of December 31, 2023, regarding our common stock that may be issued under (1) the 2017 Plan; (2) our 2017 Employee Stock Purchase Plan, (the 2017 ESPP); and (3) the 2022 Inducement Plan.

Number of Securities Weighted-Average Number of Securities

to be Issued Upon Exercise Exercise Price Available for Future

Equity compensation plans approved by stockholders

Equity compensation plans not approved by stockholders — — —

(1) The 2017 Plan provides for an annual increase on each January 1 commencing in 2018 and ending in 2027, by an amount equal to 4% of the number of shares of common stock outstanding as of the end of the immediately preceding fiscal year, provided that the Board may provide for no increase or that the increase will be a lesser number of shares.

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(2) The 2017 ESPP provides for an annual increase on each January 1 commencing in 2018 and ending in 2027, by an amount equal to the lesser of (i) 1% of the number of shares of common stock outstanding as of the end of the immediately preceding fiscal year or (ii) 682,102, provided that the Board may provide for no increase or that the increase will be a lesser number of shares.

(3) The 2022 Inducement Plan adopted on February 9, 2022. Awards issued under the 2022 Inducement Plan may only be made to a newly hired employee who has not previously been a member of the Company’s board of directors, or an employee who is being rehired following a bona fide period of non-employment by the Company or a subsidiary, as a material inducement to the employee’s entering into employment with the Company or its subsidiary. An aggregate of 1,000,000 shares of the Company’s common stock were reserved for issuance under the 2022 Inducement Plan. The material terms of the 2022 Inducement Plan are described in Note 9 to the consolidated financial statements included herein.

Other

The remaining information required under this item is incorporated herein by reference to our definitive proxy statement for our 2024 annual meeting of stockholders, which proxy statement will be filed with the Securities and Exchange commission not later than 120 days after the close of our fiscal year ended December 31, 2023

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accountant Fees and Services

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PART IV

Item 15. Exhibits and Financial Statement Schedules

(a)1. Consolidated Financial Statements.

For a list of the consolidated financial statements included herein, see Index on page F-1 of this report.

2. Financial Statement Schedules.

All financial statement schedules have been omitted because the required information is either presented in the consolidated financial statements or the notes thereto or is not applicable or required.

3. List of Exhibits.

The following is a list of exhibits filed as part of this Annual Report.

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Exhibit Index

Incorporated by Reference

Exhibit Number Exhibit Description Form Date Number

4.1 Form of Common Stock Certificate. S-1/A 9/25/2017 4.1

10.1† Form of Indemnification Agreement. S-1/A 9/25/2017 10.1

10.6†* Summary of Non-Employee Director Compensation Policy

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21.1* List of Subsidiaries.

97†* Policy for Recovery of Erroneously Awarded Compensation

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because its XBRL tags are embedded within the Inline XBRL document.

101.SCH* Inline XBRL Taxonomy Extension Schema Document.

101.LAB* Inline XBRL Taxonomy Extension Label Linkbase Document.

* Filed herewith.

** Furnished and not filed herewith.

† Indicates management contract or compensatory plan.

‡ Indicates confidential treatment has been requested with respect to specific portions of this exhibit. Omitted portions have been filed with the Securities and Exchange Commission pursuant to Rule 406 of the Securities Act.

Item 16. Form 10-K Summary

None

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SIGNATURES

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

RHYTHM PHARMACEUTICALS, INC.

By: /s/ David P. Meeker M.D.

David P. Meeker M.D.

President and Chief Executive Officer

Pursuant to the requirements of the Securities 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.

Name Title Date

David P. Meeker M.D. (Principal Executive Officer)

/s/ Hunter Smith Chief Financial Officer February 29, 2024

Hunter Smith (Principal Financial Officer)

/s/ Christopher P. German Corporate Controller February 29, 2024

Christopher P. German (Principal Accounting Officer)

/s/ Edward T. Mathers Lead Director February 29, 2024

Edward T. Mathers

/s/ Stuart Arbuckle Director February 29, 2024

Stuart Arbuckle

/s/ Camille L. Bedrosian, M.D. Director February 29, 2024

Camille L. Bedrosian M.D.

/s/ Jennifer L. Good Director February 29, 2024

Jennifer L. Good

/s/ Christophe R. Jean Director February 29, 2024

Christophe R. Jean

/s/ David W. J. McGirr Director February 29, 2024

David W. J. McGirr

/s/ Lynn A. Tetrault Director February 29, 2024

Lynn A. Tetrault

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RHYTHM PHARMACEUTICALS, INC.

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Page No.

Report of Independent Registered Public Accounting Firm (PCAOB ID No. 42) F-2

Audited Consolidated Financial Statements:

Consolidated Balance Sheets F-4

Consolidated Statements of Operations and Comprehensive Loss F-5

Consolidated Statements of Stockholders’ Equity F-6

Consolidated Statements of Cash Flows F-7

Notes to Consolidated Financial Statements F-8

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Stockholders and the Board of Directors of Rhythm Pharmaceuticals, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Rhythm Pharmaceuticals, Inc. (the Company) as of December 31, 2023 and 2022, the related consolidated statements of operations and comprehensive loss, stockholders’ equity and cash flows for each of the three years in the period ended December 31, 2023, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Company at December 31, 2023 and 2022, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2023, in conformity with U.S. generally accepted accounting principles.

We also have audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2023, based on criteria established in Internal Control-Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (2013 framework), and our report dated February 29, 2024 expressed an adverse opinion thereon.

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 U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

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

Accrued and Prepaid Research and Development Expenses

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/s/ Ernst & Young LLP

We have served as the Company’s auditor since 2015.

Boston, Massachusetts

February 29, 2024

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RHYTHM PHARMACEUTICALS, INC.

CONSOLIDATED BALANCE SHEETS

(in thousands, except share and per share data)

December 31, December 31,

Assets

Current assets:

Prepaid expenses and other current assets 8,931 11,807

Property and equipment, net 1,341 2,197

Right-of-use asset 781 1,182

Intangible assets, net 7,028 7,883

Liabilities and stockholders’ equity

Current liabilities:

Accrued expenses and other current liabilities 48,262 32,894

Long-term liabilities:

Lease liability, non-current 490 1,260

Commitments and contingencies (Note 12)

Stockholders’ equity:

Accumulated other comprehensive income (loss) 134 (92)

Total liabilities and stockholders’ equity $ 332,745 $ 382,481

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

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RHYTHM PHARMACEUTICALS, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

(in thousands, except share and per share data)

Year Ended Year Ended Year Ended

December 31, December 31, December 31,

Revenues:

License revenue — 6,754 —

Costs and expenses:

Other income (expense):

Interest expense (13,892) (5,201) —

Provision for income taxes 564 — —

Net loss per share, basic and diluted $ (3.20) $ (3.47) $ (1.40)

Other comprehensive loss:

Foreign currency translation adjustment (140) — —

Unrealized gain (loss), net on marketable securities 366 (91) (1)

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

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RHYTHM PHARMACEUTICALS, INC.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY

(in thousands, except share data)

Accumulated

Additional Other Total

Common Stock Paid-In Comprehensive Accumulated Stockholders’

Shares Amount Capital Income (Loss) Deficit Equity

Stock compensation expense — — 20,804 — — 20,804

Net unrealized loss on marketable securities — — — (50) — (50)

Net loss — — — — (69,612) (69,612)

Stock compensation expense — — 19,831 — — 19,831

Net unrealized loss on marketable securities — — — (91) — (91)

Stock compensation expense — — 32,553 — — 32,553

Net unrealized gain on marketable securities — — — 366 — 366

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

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RHYTHM PHARMACEUTICALS, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(in thousands)

Year ended December 31,

Operating activities

Gain on sale of priority review voucher — — (100,000)

Loss on RareStone equity investment — 1,040 —

Change in fair value of embedded derivative liability (190) (250) —

Acquired IPR&D assets classified as investing activities 5,667 — —

Changes in operating assets and liabilities:

Prepaid expenses and other current assets 2,876 498 (3,339)

Deferred revenue (148) (6,606) —

Investing activities

Proceeds from sale of priority review voucher — — 100,000

Proceeds from out-license agreement — — 7,000

Acquisition of IPR&D assets, including transaction costs (5,667) — —

Purchases of property and equipment (47) (281) (434)

Financing activities

Repayment of deferred royalty obligation (7,398) — —

Proceeds from the exercise of stock options 7,468 9,752 4,134

Proceeds from issuance of common stock from ESPP 1,053 626 621

Effect of exchange rates on cash (142) — —

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

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Rhythm Pharmaceuticals, Inc.

Notes to Consolidated Financial Statements

(In thousands, except share and per share information)

1. Nature of Business

Rhythm Pharmaceuticals, Inc. (the “Company” or “we”) is a global, commercial-stage biopharmaceutical company dedicated to transforming the lives of patients and their families living with rare neuroendocrine diseases. We are focused on advancing our melanocortin-4 receptor agonists, including our lead asset, IMCIVREE® (setmelanotide), as a precision medicine designed to treat hyperphagia and severe obesity caused by MC4R pathway diseases. While obesity affects hundreds of millions of people worldwide, we are developing therapies for a subset of individuals who have hyperphagia, a pathological hunger, and severe obesity due to an impaired MC4R pathway, which may be caused by traumatic injury or genetic variants. The MC4R pathway is an endocrine pathway in the brain that is responsible for regulating hunger, caloric intake and energy expenditure, which consequently affect body weight. IMCIVREE, an MC4R agonist for which we hold worldwide rights, is the first-ever therapy developed for patients with certain rare diseases that is approved or authorized in the United States, European Union (EU), Great Britain, Canada and other countries and regions.

The Company is a Delaware corporation organized in February 2013 under the name Rhythm Metabolic, Inc., and as of October 2015, under the name Rhythm Pharmaceuticals, Inc. The Company has wholly owned subsidiaries in the US, Ireland, the United Kingdom, the Netherlands, France, Germany, Italy, Spain and Canada.

The Company is subject to risks and uncertainties common to commercial-stage companies in the biotechnology industry, including but not limited to, risks associated with the commercialization of approved products, completing preclinical studies and clinical trials, receiving regulatory approvals for product candidates, development by competitors of new biopharmaceutical products, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. Commercialization of approved products will require significant resources and in order to market IMCIVREE, the Company must continue to build its sales, marketing, managerial and other non-technical capabilities or make arrangements with third parties to perform these services. Product candidates currently under development will require significant additional research and development efforts, including preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel and infrastructure and extensive compliance-reporting capabilities. Even though the Company has an approved product, and even if the Company’s further product development efforts are successful, it is uncertain when, if ever, the Company will realize sufficient revenue from product sales to fund operations.

Liquidity

The Company has incurred operating losses and negative cash flows from operations since inception. As of December 31, 2023, the Company had an accumulated deficit of $894,736. The Company has primarily funded these losses through the proceeds from the sales of common and preferred stock, asset sales, royalty financing, out-license arrangements, as well as capital contributions received from the former parent company, Rhythm Holdings LLC. To date, the Company has minimal product revenue and management expects operating losses to continue for the foreseeable future. The Company has devoted substantially all of its resources to its drug development efforts, comprising of research and development, the acquisition of in process research and development assets, manufacturing, conducting clinical trials for its product candidates, protecting its intellectual property, commercialization activities and general and administrative functions relating to these operations. The future success of the Company is dependent on its ability to develop its product candidates and ultimately upon its ability to attain profitable operations.

At December 31, 2023, the Company had $275,846 of cash and cash equivalents and short-term investments on hand. In the future, the Company will be dependent on obtaining funding from third parties, such as proceeds from the

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issuance of debt, sale of equity, proceeds from out license arrangements, product sales and funded research and development programs to maintain the Company's operations and meet the Company's obligations. There is no guarantee that additional equity or other financings will be available to the Company on acceptable terms, or at all. If the Company fails to obtain additional funding when needed, the Company would be forced to scale back, terminate its operations or seek to merge with or be acquired by another company. Management believes that the Company's existing cash resources will be sufficient to fund the Company's operations through at least the next twelve months from the filing of this Annual Report on Form 10-K with the SEC.

2. Summary of Significant Accounting Policies

Basis of Presentation

The Company's consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”).

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. The Company bases its estimates on historical experience and other market-specific or other relevant assumptions that it believes to be reasonable under the circumstances. This process may result in actual results differing materially from those estimated amounts used in the preparation of the financial statements if these results differ from historical experience, or other assumptions do not turn out to be substantially accurate, even if such assumptions are reasonable when made. Significant estimates relied upon in preparing these financial statements include estimates related to determining our net product revenue, license revenue, accruals related to research and development expenses, assumptions used to record stock-based compensation expense, interest expense on our deferred royalty obligation, assumptions used to value the embedded derivative in our deferred royalty obligation, assumptions used to value the common stock received from RareStone Group Ltd., or RareStone, and the valuation allowance on the Company's deferred tax assets. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ materially from those estimates.

Principles of Consolidation

The consolidated financial statements include the accounts of Rhythm Pharmaceuticals, Inc. and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.

Reclassifications

Certain prior year amounts have been reclassified to conform to the current period presentation. These reclassifications had no effect on the reported results of operations or cash flows. Specifically, in the consolidated statement of cash flows for the year ended December 31, 2022, the Company has reclassified $2,314 from changes in prepaid expenses and other current assets to non-cash accretion and amortization of short-term investments.

Segment Information

Operating segments are defined as components of an entity about which separate discrete information is available for evaluation by the chief operating decision maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company currently operates in one business segment, which is the development and commercialization of therapies for patients with rare diseases. A single management team that reports to the Chief

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Executive Officer comprehensively manages the entire business. The Company does not operate separate lines of business with respect to its product or product candidates. Accordingly, the Company has one reportable segment.

Off-Balance Sheet Risk and Concentrations of Credit Risk

Financial instruments, which potentially subject the Company to significant concentration of credit risk, consist primarily of cash and cash equivalents and short-term investments, which are maintained at two federally insured financial institutions. The deposits held at these two institutions are in excess of federally insured limits. The Company has not experienced any losses in such accounts and management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held. The Company has no off-balance sheet risk, such as foreign exchange contracts, option contracts, or other foreign hedging arrangements.

The Company is exposed to risks associated with extending credit to customers related to the sale of products. The Company does not require collateral to secure amounts due from its customers. For the years ended December 31, 2023 and 2022, approximately 77% and 85%, respectively, of all of the Company’s revenue was generated from a single customer in the United States. As of December 31, 2023 and 2022, approximately 67% and 80%, respectively, of the Company’s accounts receivable was outstanding from a single customer in the United States.

The Company relies on third-party manufacturers and suppliers for manufacturing and supply of its product. The inability of the suppliers or manufacturers to fulfill supply requirements of the Company could materially impact future operating results. A change in the relationship with the suppliers or manufacturer, or an adverse change in their business, could materially impact future operating results.

The Company relies on separate third parties to perform genetic testing in the United States and Europe, respectively. The inability of the vendor to fulfill testing services for the Company could materially impact future operating results and adversely impact our ability to further develop setmelanotide. A change in the relationship with the genetic testing service providers, or an adverse change in their business, could materially impact future operating results.

Cash and Cash Equivalents

The Company considers all highly liquid investments with remaining maturity from the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents includes bank demand deposits, U.S. treasury bills and money market funds that invest primarily in U.S. government treasuries.

Short-Term Investments

Short-term investments consist of investments with maturities greater than 90 days, as of the date of purchase. The Company has classified its investments with maturities beyond one year as short term, based on their highly liquid nature and because such marketable securities represent the investment of cash that is available for current operations. The Company considers its investment portfolio available-for-sale. Accordingly, these investments are recorded at fair value, which is based on quoted market prices. Unrealized gains and losses are reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity. To the extent the amortized cost basis of the available-for-sale debt securities exceeds the fair value, management assesses the debt securities for credit loss; however, management considers the risk of credit loss to be minimized by the Company's policy of investing in financial instruments issued by highly-rated financial institutions. When assessing the risk of credit loss, management considers factors such as the severity and the reason of the decline in value (i.e., any changes to the rating of the security by a rating agency or other adverse conditions specifically related to the security) and management's intended holding period and time horizon for selling. During the years ended December 31, 2023, 2022, and 2021, the Company did not recognize any credit losses related to its available-for-sale debt securities. Further, as of December 31, 2023 and 2022, the Company did not record an allowance for credit losses related to its available-for-sale debt securities.

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Restricted Cash

Restricted cash consists of security deposits in the form of letters of credit placed in separate restricted bank accounts as required under the terms of the Company’s lease arrangement for its corporate office in Boston, Massachusetts and the Company’s corporate travel credit card.

Accounts Receivable, net

Accounts receivable consists of amounts due from customers, net of customer allowances for cash discounts and any estimated expected credit losses. The Company's measurement of expected credit losses is based on relevant information about past events, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. To date, the Company has not experienced any credit losses. The Company's contracts with its customers have customary payment terms that generally require payment within 90 days. The Company analyzes amounts that are past due for collectability, and periodically evaluates the creditworthiness of its customer. At December 31, 2023 and 2022, the Company determined an allowance for doubtful account was not required based upon our review of contractual payments and our customer circumstances.

Revenue Recognition

The Company recognizes revenue in accordance with ASC Topic 606, Revenue from Contracts with Customers, or ASC 606. Under ASC 606, an entity recognizes revenue when its customer obtains control of promised goods or services in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services.

Product Revenue, Net

In the United States (the “U.S.”), which accounts for the largest portion of our total revenues, the Company sells its product to a limited number of specialty pharmacies. The product is distributed through a third-party logistics, or 3PL, distribution agent that does not take title to the product. Once the product is delivered to the Company’s specialty pharmacy provider, our customer in the U.S., the customer (or “wholesaler”) takes title to the product. The wholesaler then distributes the product to patients. In our distribution agreement with the 3PL company, the Company acts as principal because we retain control of the product. Internationally, we make sales primarily to specialty distributors and retail pharmacy chains, as well as hospitals, many of which are government-owned or supported. The Company generally does not offer returns of product sold to the customer.

Revenue from product sales is recognized when the customer obtains control of our product, which occurs at a point in time, upon transfer of title to the customer because at that point in time we have no ongoing obligations to the customer. There are no other performance obligations besides the sale of product. We classify payments to our customers or other parties in the distribution channel for services that are distinct and priced at fair value as selling, general and administrative expenses in our consolidated statements of operations and comprehensive (loss) income. Otherwise, payments to a customer or other parties in the distribution channel that do not meet those criteria are classified as a reduction of revenue, as discussed further below. Taxes collected from the customer relating to product sales and remitted to governmental authorities are excluded from revenue. Because our payment terms are generally ninety days or less, the Company concluded there is not a significant financing component because the period between the transfer of a promised good or service to the customer and when the customer pays for that good or service will be one year or less. The Company expenses incremental costs of obtaining a contract as and when incurred since the expected amortization period of the asset that we would have recognized is one year or less.

Reserves for Variable Consideration

Revenues from product sales are recorded at the net sales price, or the transaction price, which includes estimates of variable consideration for which reserves are established and which result from discounts, returns, chargebacks, rebates, co-pay assistance and other allowances that are offered within contracts between us and our customers, health care providers and other indirect customers relating to the sale of IMCIVREE. These reserves are based on the amounts earned or to be claimed on the related sales and are classified as reductions of accounts receivable (if the amount is payable to the

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customer) or a current liability (if the amount is payable to a party other than a customer). Where appropriate, these estimates take into consideration a range of possible outcomes that are probability-weighted for relevant factors such as our historical experience, current contractual and statutory requirements, specific known market events and trends, industry data and forecasted customer buying and payment patterns. Overall, these reserves reflect our best estimates of the amount of consideration to which we are entitled based on the terms of the contract. The amount of variable consideration that is included in the transaction price may be constrained and is included in the net sales price only to the extent that it is considered probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. Actual amounts of consideration ultimately received may differ from our estimates. If actual results in the future vary from our estimates, we will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known.

The following are the components of variable consideration related to product revenue:

Chargebacks: The Company estimates obligations resulting from contractual commitments with the government and other entities to sell products to qualified healthcare providers and patients at prices lower than the list prices charged to our customers. The government and other entities charge us for the difference between what they pay for the product and the selling price to our customers. The Company records reserves for these chargebacks related to product sold to our customers during the reporting period, as well as our estimate of product that remains in the distribution channel at the end of the reporting period that we expect will be sold to qualified healthcare providers and patients in future periods.

Government rebates: The Company is subject to discount obligations under government programs, including Medicaid programs, Medicare and Tricare in the United States as well as certain government rebates and pricing adjustments in certain international markets that we operate. We estimate Medicaid, Medicare and Tricare rebates based upon a range of possible outcomes that are probability-weighted for the estimated payer mix. These reserves are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a liability that is included in accrued expenses and other current liabilities on our consolidated balance sheets. For Medicare, we also estimate the number of patients in the prescription drug coverage gap for whom we will owe an additional liability under the Medicare Part D program. On a quarterly basis, we update our estimates and record any adjustments in the period that we identify the adjustments.

Trade discounts and allowances: The Company provides customary invoice discounts on IMCIVREE sales to certain of our customers for prompt payment that are recorded as a reduction of revenue in the period the related product revenue is recognized. In addition, we receive and pay for various distribution services from our customers in the distribution channel. For services that are either not distinct from the sale of our product or for which we cannot reasonably estimate the fair value, such fees are classified as a reduction of product revenue.

Product returns: Our customers have limited return rights related to the product’s damage or defect. The Company estimates the amount of product sales that may be returned and records the estimate as a reduction of revenue and a refund liability in the period the related product revenue is recognized. Based on the distribution model for IMCIVREE and the price of IMCIVREE, the Company believes there will be minimal returns.

Other incentives: Other incentives include co-payment assistance the Company provides to patients with commercial insurance that have coverage and reside in states that allow co-payment assistance. The calculation of the accrual for co-pay assistance is based on an estimate of claims and the cost per claim that we expect to receive associated with product that has been recognized as revenue. The estimate is recorded as a reduction of revenue in the same period the related revenue is recognized.

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The table below summarizes balances and activity in each of the product revenue allowance and reserve categories as follows:

Provision for Cash Discounts Fees, Rebates and Other Incentives Total

Provision related to sales in the current year 367 3,299 3,666

Provision related to sales in the current year 1,672 17,351 19,023

RYTM US Equity

RYTM · 10-K · period ended 2023-12-31

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

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosures

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections.

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accountant Fees and Services

Item 15. Exhibits and Financial Statement Schedules

Item 16. Form 10-K Summary

RYTM US Equity☆

RYTM · 10-K · period ended 2023-12-31

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

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosures

Item 9A. Controls and Procedures

Item 9B. Other Information​​

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections.

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Transactions, and Director Independence

Item 14. Principal Accountant Fees and Services

Item 15. Exhibits and Financial Statement Schedules

Item 16. Form 10-K Summary

RYTM US Equity

Item 9B. Other Information