Release Details

-- Amendment revised royalty structure from low-to-mid-single digits to 1% on global net sales of Rhythm MC4R agonists, including setmelanotide, bivamelagon and RM-718 --

-- Rhythm to pay LG Chem additional fixed payments totaling $350 million over four years --

-- Rhythm secures $750 million term-loan facility led by KKR’s HealthCare Royalty in partnership with Blackstone to support the amended LG Chem agreement, global commercialization efforts and continued pipeline investment --

BOSTON, Nov. 02, 2026 (GLOBE NEWSWIRE) -- Rhythm Pharmaceuticals, Inc. (Nasdaq: RYTM) today announced an amendment to the global exclusive license agreement with LG Chem, Ltd. for bivamelagon, an investigational oral small-molecule melanocortin-4 receptor (MC4R) agonist. The Company also announced a five-year term loan facility led by KKR’s HealthCare Royalty (“HealthCare Royalty”) in partnership with funds managed by Blackstone (“Blackstone”), providing access to up to $750 million of capital.

“MC4R agonism has been shown to achieve a profound impact on patients living with hyperphagia and severe obesity associated with rare MC4R pathway diseases,” said David Meeker, M.D., Chairman, President and Chief Executive Officer of Rhythm. “With its deep scientific expertise, LG Chem succeeded where many failed in developing the first oral MC4R agonist in bivamelagon, which has been shown to achieve clinically meaningful weight loss in patients living with acquired hypothalamic obesity (HO). Our commitment to this program reflects our confidence in bivamelagon’s potential to deliver meaningful benefits for patients and create substantial long-term value for shareholders.”

“This amendment reflects the strong confidence both companies have in the value and potential of bivamelagon,” said Jeewoong Son, President of LG Chem Life Sciences Company. “By expanding global development efforts, we hope to accelerate patient access to an innovative treatment option for rare obesity diseases.”

Bivamelagon Licensing Agreement
In January 2024, Rhythm entered into a global licensing agreement with LG Chem for exclusive worldwide rights to develop and commercialize bivamelagon, then known as LB54640. Under the original agreement, Rhythm paid LG Chem a total of $80 million in cash and $20 million in Rhythm common stock and agreed to potential regulatory and sales milestone payments of up to $205 million, as well as commercial sales royalties of low-to-mid-single digits on global net sales of products within Rhythm’s MC4R portfolio, dependent upon the number of indications approved by regulatory authorities.

Under the terms of the amended agreement, Rhythm will make additional fixed payments totaling $350 million to LG Chem in four installments: $70 million within 15 business days following the effective date of the Amendment, which is Nov. 2, 2026; $100 million in September 2027; $100 million in September 2028; and $80 million in September 2029. In addition, the variable royalty structure in the original agreement will be replaced with a 1% royalty on global net sales of products within Rhythm’s MC4R portfolio, beginning on January 1, 2029, or upon the first commercial sale of bivamelagon, if earlier.

With LG Chem's agreement, Rhythm may satisfy certain of the foregoing fixed payment obligations through additional royalties.

In addition to potential development, regulatory and commercial milestone payments totaling up to $205 million in the original agreement, the amendment includes an additional milestone payment of up to $200 million based on achievement of $3 billion in annual global net sales of its MC4R portfolio.

Term Loan Facility Highlights:
Today, Rhythm also announced that it has entered into a $750 million term-loan facility, with $500 million committed, led by KKR’s HealthCare Royalty in partnership with Blackstone, to support the amended licensing agreement with LG Chem as well as ongoing global commercialization efforts and R&D programs.

The five-year term loan facility includes an initial $250 million draw at closing, which is expected to occur on November 6, 2026, subject to the satisfaction of customary closing conditions, and up to $250 million of additional committed capital through June 30, 2028 at Rhythm’s option, in three delayed-draw tranches consisting of two tranches of $100 million and one tranche of $50 million. In addition, Rhythm has access to an additional $250 million by mutual agreement. Borrowings under the facility will bear interest at the Secured Overnight Financing Rate, or SOFR, plus 4.60%. The five-year loan has no scheduled principal amortization prior to maturity and no equity component. The facility includes customary prepayment premiums that decline over the term of the loan.

In connection with the term loan, Rhythm and HealthCare Royalty have agreed to amend the Company’s existing revenue interest financing agreement, with the amendment expected to become effective upon the closing of the term loan. The amendments remove the debt-like covenants and default provisions, limit the collateral securing the agreement and modify the agreement’s material adverse effect provisions.

“We value our partnership with HealthCare Royalty and welcome our new partnership with Blackstone. We believe the mutually beneficial terms of this financing agreement enhance our financial flexibility while positioning us to create meaningful long-term shareholder value,” said Hunter C. Smith, Chief Financial Officer of Rhythm.

“Rhythm has established a clear leadership position in MC4R pathway diseases, supported by a growing commercial foundation and a differentiated pipeline spanning multiple potential indications,” said Clarke B. Futch, Chairman and Chief Executive Officer of HealthCare Royalty.

M. Craig Shepherd, Senior Managing Director, Blackstone, added, “We are pleased to partner with Rhythm and HealthCare Royalty through a financing structure that supports the Company’s long-term strategy and reflects our shared confidence in the value and potential of its MC4R portfolio.”

J. Wood Capital Advisors served as financial advisor to Rhythm in connection with the financing.

About Rhythm Pharmaceuticals
Rhythm is a commercial-stage biopharmaceutical company committed to transforming the lives of patients and their families living with rare neuroendocrine diseases. Rhythm’s lead asset, IMCIVREE^® (setmelanotide), an MC4R agonist designed to treat hyperphagia and severe obesity, is approved by the U.S. Food and Drug Administration (FDA) to reduce excess body weight and maintain weight reduction long term in adult and pediatric patients aged 4 years and older with acquired hypothalamic obesity, adult and pediatric patients 2 years of age and older with syndromic or monogenic obesity due to Bardet-Biedl syndrome (BBS) or genetically confirmed pro-opiomelanocortin (POMC), including proprotein convertase subtilisin/kexin type 1 (PCSK1), deficiency or leptin receptor (LEPR) deficiency. Both the European Commission (EC) and the UK’s Medicines and Healthcare Products Regulatory Agency (MHRA) have authorized setmelanotide for the treatment of obesity and control of hunger in patients 4 years of age and above with acquired hypothalamic obesity due to hypothalamic injury or impairment; and 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 2 years of age and above. Additionally, Rhythm is advancing a broad clinical development program for setmelanotide in other rare diseases, as well as investigational MC4R agonists bivamelagon and RM-718, and a preclinical suite of small molecules for the treatment of congenital hyperinsulinism. Rhythm’s headquarters is in Boston, MA.

About LG Chem
LG Chem is a leading global chemical company with a diversified business portfolio spanning across petrochemicals, advanced materials, and life sciences. LG Chem Life Sciences, the life sciences business division of LG Chem, is dedicated to developing and delivering innovative medicines across a broad range of therapeutic areas. Guided by its mission to transform people’s lives through inspiring science and leading innovation, LG Chem Life Sciences is offering differentiated solutions to its customers. For more information, please visit www.lgchem.com.

About HealthCare Royalty, a business of KKR
HealthCare Royalty is a leading royalty acquisition company founded in 2006 that is majority owned by KKR & Co. Inc. (NYSE: KKR). Over two decades, the HealthCare Royalty team has developed a strong track record of investing in commercial-stage and near-commercial-stage biopharmaceutical assets, committing $8+ billion in over 110 biopharmaceutical products. With offices in New York, San Francisco, Boston, London and Miami, HealthCare Royalty continues to advance biopharmaceutical innovation by providing innovative capital solutions to counterparties. For more information, visit https://www.hcrx.com. HEALTHCARE ROYALTY^® and HCRx^® are registered trademarks of HealthCare Royalty Management, LLC.

About Blackstone
Blackstone is the world’s largest alternative asset manager. Blackstone seeks to deliver compelling returns for institutional and individual investors by strengthening the companies in which the firm invests. Blackstone’s nearly $1.4 trillion in assets under management include global investment strategies focused on real estate, private equity, credit, infrastructure, life sciences, growth equity, secondaries and hedge funds. Further information is available at www.blackstone.com. Follow @blackstone on LinkedIn, X (Twitter), and Instagram.  

Setmelanotide Indication
In the United States, setmelanotide is indicated to reduce excess body weight and maintain weight reduction long term in adults and pediatric patients aged 4 years and older with acquired hypothalamic obesity, in adult and pediatric patients aged 2 years and older with syndromic or monogenic obesity due to Bardet-Biedl syndrome (BBS) or Pro-opiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1), or leptin receptor (LEPR) deficiency confirmed by genetic testing demonstrating variants in POMC, PCSK1, or LEPR genes that are interpreted as pathogenic, likely pathogenic, or of uncertain significance (VUS).

In the European Union and the United Kingdom, setmelanotide is indicated for the treatment of obesity and the control of hunger associated with genetically confirmed BBS or loss-of-function biallelic POMC, including PCSK1, deficiency or biallelic LEPR deficiency in adults and children 2 years of age and above, and for the treatment of obesity and control of hunger in adults and children 4 years of age and above with acquired hypothalamic obesity due to hypothalamic injury or impairment. In the European Union and the United Kingdom, setmelanotide should be prescribed and supervised by a physician experienced in the diagnosis and management of rare forms of obesity with genetic or hypothalamic origin.

Limitations of Use

Setmelanotide is not indicated for the treatment of patients with the following conditions as setmelanotide would not be expected to be effective:

• Obesity due to suspected POMC, PCSK1, or LEPR deficiency with POMC, PCSK1, or LEPR variants classified as benign or likely benign
• Other types of obesity not related to acquired HO, BBS, or POMC, PCSK1 or LEPR deficiency, including obesity associated with other genetic syndromes and general (polygenic) obesity.

Important Safety Information

CONTRAINDICATIONS

Prior serious hypersensitivity to setmelanotide or any of the excipients in IMCIVREE. Serious hypersensitivity reactions (e.g., anaphylaxis) have been reported.

WARNINGS AND PRECAUTIONS

Disturbance in Sexual Arousal: Spontaneous penile erections and increased frequency of penile erections in males have occurred. Inform patients that these events may occur and instruct patients who have an erection lasting longer than 4 hours to seek emergency medical attention.

Depression and Suicidal Ideation: Depression and suicidal ideation have occurred. Monitor patients for new onset or worsening depression or suicidal thoughts or behaviors. Consider discontinuing IMCIVREE if patients experience suicidal thoughts or behaviors, or clinically significant or persistent depression symptoms occur.

Hypersensitivity Reactions: Serious hypersensitivity reactions (e.g., anaphylaxis) have been reported. If suspected, advise patients to promptly seek medical attention and discontinue IMCIVREE.

Skin Hyperpigmentation, Darkening of Pre-existing Nevi, and Development of New Melanocytic Nevi: Generalized or focal increases in skin pigmentation occurred in the majority of IMCIVREE-treated patients. IMCIVREE may also cause development of new melanocytic nevi or darkening of pre-existing nevi. Perform a full body skin examination prior to initiation and periodically during treatment to monitor pre-existing and new pigmented lesions.

Acute Adrenal Insufficiency with Acquired HO: Patients with acquired HO and secondary adrenal insufficiency reported serious adverse reactions related to acute adrenal insufficiency in 5% of IMCIVREE-treated patients and no placebo-treated patients. In patients with secondary adrenal insufficiency, monitor for clinical signs of acute adrenal insufficiency.

Sodium Imbalance in Patients with Acquired HO and Central Diabetes Insipidus: Patients with acquired HO and concomitant central diabetes insipidus (DI)/arginine vasopressin (AVP) deficiency reported hyponatremia in 6% of IMCIVREE-treated patients and 2% of placebo-treated patients and hypernatremia in 5% of IMCIVREE-treated patients and 4% of placebo-treated patients. Monitor serum sodium levels with changes in fluid intake and hydration status. Adjust the doses of concomitant therapies for DI/AVP deficiency as needed.

ADVERSE REACTIONS

Most common adverse reactions (incidence ≥20% in at least 1 indication) included skin hyperpigmentation, injection site reactions, nausea, headache, diarrhea, abdominal pain, vomiting, depression, and spontaneous penile erection.

USE IN SPECIFIC POPULATIONS

Treatment with IMCIVREE is not recommended when breastfeeding. Discontinue IMCIVREE when pregnancy is recognized unless the benefits of therapy outweigh the potential risks to the fetus.

To report SUSPECTED ADVERSE REACTIONS, contact Rhythm Pharmaceuticals at +1 (833) 789-6337 or FDA at 1-800-FDA-1088 or http://www.fda.gov/medwatch. See section 4.8 of the Summary of Product Characteristics for information on reporting suspected adverse reactions in Europe.

Please see the full Prescribing Information for additional Important Safety Information.

Forward-looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. All statements contained in this press release that do not relate to matters of historical fact should be considered forward-looking statements, including, without limitation, statements regarding the safety, efficacy, potential benefits of, and clinical design or progress of any of our products or product candidates at any dosage or in any indication, including, setmelanotide, bivamelagon, and RM-718; our continued collaboration with LG Chem; the anticipated benefits of the term loan; the expected timing of the closing and initial funding of the term loan and the effectiveness of the amendment to our revenue interest financing agreement; the estimated market size and addressable population for our drug products, including setmelanotide for the treatment of acquired HO; and the timing of any of the foregoing. Statements using words such as “expect”, “anticipate”, “believe”, “may”, “will” and similar terms are also forward-looking statements. Such statements are subject to numerous risks and uncertainties, including, but not limited to, the satisfaction of the conditions to closing of the term loan, our ability to enroll patients in clinical trials, the design and outcome of clinical trials, the impact of competition, the ability to achieve or obtain necessary regulatory approvals, risks associated with data analysis and reporting, unfavorable pricing regulations, third-party reimbursement practices or healthcare reform initiatives, risks associated with the laws and regulations governing our international operations and the costs of any related compliance programs, our ability to successfully commercialize setmelanotide, our liquidity and expenses, our ability to retain our key employees and consultants, and to attract, retain and motivate qualified personnel, and general economic conditions, and the other important factors, including those discussed under the caption “Risk Factors” in Rhythm’s Quarterly Report on Form 10-Q for the three months ended June 30, 2026, and in Rhythm’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2026 to be filed with the Securities and Exchange Commission (the “SEC”) and our other filings with the SEC. Except as required by law, we undertake no obligations to make any revisions to the forward-looking statements contained in this release or to update them to reflect events or circumstances occurring after the date of this release, whether as a result of new information, future developments or otherwise.

Corporate Contacts:
David Connolly
Head of Investor Relations and Corporate Communications
Rhythm Pharmaceuticals, Inc.
857-264-4280
dconnolly@rhythmtx.com  

Kate Walsh
Director, Corporate Communications
Rhythm Pharmaceuticals, Inc.
(857) 264-4280
kwalsh@rhythmtx.com