MAGEL2

-- Four Pediatric patients treated in French early-access program achieved meaningful weight reduction at three months on setmelanotide therapy -- -- Rhythm announced plans for a new substudy to evaluate setmelanotide therapy in patients with congenital hypothalamic obesity -- BOSTON, Nov. 18, 2024 (GLOBE NEWSWIRE) -- Rhythm Pharmaceuticals, Inc. (Nasdaq: RYTM), a commercial-stage biopharmaceutical company focused on transforming the lives of patients living with rare neuroendocrine diseases, today announced the presentation of new, real-world data that showed four pediatric patients with acquired hypothalamic obesity or congenital hypothalamic obesity achieved >5% weight reduction at three months on setmelanotide, a melanocortin-4 receptor (MC4R) agonist. These data were among five Rhythm-related presentations delivered during the 62nd annual meeting of the European Society for Paediatric Endocrinology (EPSE) in Liverpool, England. “Patients living with hypothalamic obesity – whether acquired or congenital –are mostly refractory to lifestyle programs and anti-obesity medicines that do not address the underlying cause,” said David Meeker, M.D., Chairman, Chief Executive Officer and President of Rhythm. “Based on these case reports and insight generated through our pre-approval early-access program for setmelanotide in France, we look forward to exploring the potential efficacy of setmelanotide to offer a new therapy for these patients.” 3-month real-world setmelanotide hunger and weight outcomes in four French pediatric patients with acquired or congenital hypothalamic obesityThe presentation includes results from four case reports of patients <18 years old, two with acquired hypothalamic obesity and two with congenital hypothalamic obesity, at month three on setmelanotide therapy: Congenital hypothalamic obesity: Female, age 15, with septo-optic dysplasia as cause of hypothalamic obesity, achieved a body weight decrease of 9.6% from baseline (94 kg) at month 3 and BMI-Z score change from 3.1 at baseline to 2.8;Male, age 9, with pituitary stalk interruption syndrome (PSIS) as cause of hypothalamic obesity, achieved a body weight decrease of 5.2% from baseline (64 kg) at month 3 and BMI-Z score change from 3.7 at baseline to 3.5; Acquired hypothalamic obesity: Male, age 13, with acquired hypothalamic obesity related to craniopharyngioma resected at age 9, achieved a body weight decrease of 5.6% from baseline (116 kg) at month 3 and 9.5% weight reduction at month 6, and BMI-Z score change from 3.7 at baseline to 3.4 at month six of setmelanotide therapy; andMale, age 13, with acquired hypothalamic obesity related to radiotherapy for juvenile pilocytic astrocytoma, achieved a body weight decrease of 8.3% from baseline (88.3 kg) at month 3 and BMI-Z score change from 3.1 at baseline to 2.8. These patients were treated with setmelanotide at four different hospitals in France under a pre-marketing, early-access authorization program. All four patients remain on therapy, as of November 15, 2024, and there were no new safety signals observed. “These patients present with differences and complexities associated with hypothalamic obesity, but these conditions share the same disrupted MC4R pathway signaling,” said Dr. Ahlam Azar-Kolakez, MD, Endocrinology-Diabetology Department, Reference Center for Endocrine Growth and Developmental Diseases, Robert Debré Hospital, Assistance Publique-Hôpitaux de Paris, France. “These real-world results are the first reported evidence of setmelanotide treatment for patients with congenital hypothalamic obesity demonstrating that it may be an effective, targeted therapy for both acquired and congenital hypothalamic obesity despite differences in etiology.” Also today, Rhythm announced plans for a new, 34-week substudy designed to evaluate setmelanotide in 39 patients with congenital hypothalamic obesity aged 4 years and older. Rhythm is seeking approval from the U.S. Food and Drug Administration (FDA) for the independent substudy for congenital hypothalamic obesity as a protocol amendment to the Company’s ongoing Phase 3 trial evaluating setmelanotide in patients with acquired hypothalamic obesity. Rhythm anticipates enrolling the first patients with congenital hypothalamic obesity in the first quarter of 2025. The substudy in congenital hypothalamic obesity is independent from Rhythm’s pivotal Phase 3 trial in acquired hypothalamic obesity. The Company remains on track to disclose topline data from that pivotal trial in the first half of 2025. About Congenital Hypothalamic ObesityCongenital hypothalamic obesity is a rare disease caused by certain inborn brain abnormalities that may impair the function of the MC4R pathway, which regulates satiety or food intake and energy expenditure. The hallmark features of this disease include hyperphagia and early-onset, refractory obesity that is often linked to an impairment in the MC4R pathway associated with several pituitary deficiencies. Rare diseases that may cause congenital hypothalamic obesity include septo-optic displasia (or de Morsier syndrome), optic nerve hypoplasia, multiple pituitary hormone deficiency (also known as combined pituitary hormone deficiency) and pituitary stalk interruption syndrome. Each of these diseases is considered rare, and between 12% and 40% of patients with these diseases may have congenital hypothalamic obesity. Rhythm’s preliminary estimate of the prevalence of congenital hypothalamic obesity is in excess of 1,000 patients in the United States with a similar prevalence in Europe. Additional Presentations at ESPE 2024In a poster entitled, “Evaluating Setmelanotide Treatment for 12 Months in Pediatric Age Groups With Rare Melanocortin-4 Receptor Pathway–Related Obesity: Efficacy in Weight Reduction and Safety Outcomes,” presenters highlighted the importance of early intervention in young patients with rare MC4R pathway diseases. A cross-sectional analysis of 50 patients aged 2 to 17 years with rare MC4R pathway diseases who participated in one of five different clinical trials of setmelanotide was presented showing that patients regardless of age achieved clinically meaningful weight reductions, and that children between 2 and 5 years old achieved a greater absolute BMI Z reduction. Additionally, the Company delivered three oral presentations based on analyses of more than 5,000 sequencing samples from the Company’s European genetic testing program for individuals with suspected rare MC4R pathway diseases, Rare Obesity Advanced Diagnosis or ROAD®. Genetic testing of individuals with early-onset obesity can help improve disease etiology understanding and identify patients who may benefit from specialized care. Highlights from these three presentations included: 1.74% of individuals tested carried a biallelic variant in one of 22 tested genes related to Bardet-Biedl syndrome (BBS), and the frequency in Turkey was 5.82%, potentially due to consanguinity rates;22.5% of tested individuals with early-onset obesity carried a variant classified as pathogenic, likely pathogenic or of unknown significance (VUS) of one or more genes closely associated with MC4R pathway function: SIM1, SEMA3 family, PLXNA family, POMC, PCSK1, LEPR, SH2B1 and NCOA1; and4.9% of tested individuals carried a biallelic or heterozygous pathogenic, likely pathogenic or VUS variant in one or more of these genes: ALMS1, BBS, MAGEL2, PHIP, or TBX3 genes. These genes are associated with certain debilitating syndromes. All of the Rhythm-related presentations from ESPE 2024 are available here: https://hcp.rhythmtx.com/publications-presentations/. About Rhythm PharmaceuticalsRhythm 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) for chronic weight management in adult and pediatric patients 6 years of age and older with monogenic or syndromic obesity due to pro-opiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1) or leptin receptor (LEPR) deficiency confirmed by genetic testing, or patients with a clinical diagnosis of Bardet-Biedl syndrome (BBS). Both the European Commission (EC) and the UK’s Medicines & Healthcare Products Regulatory Agency (MHRA) have authorized setmelanotide 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. The EC has also authorized setmelanotide for control of hunger and treatment of obesity in children as young as 2 years old, living with BBS or POMC, PCSK1, or LEPR deficiency. Additionally, Rhythm is advancing a broad clinical development program for setmelanotide in other rare diseases, as well as investigational MC4R agonists LB54640 and RM-718, and a preclinical suite of small molecules for the treatment of congenital hyperinsulinism. Rhythm’s headquarters is in Boston, MA. Setmelanotide IndicationIn the United States, setmelanotide is indicated for chronic weight management in adult and pediatric patients 6 years of age and older with monogenic or syndromic obesity due to POMC, PCSK1 or 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 BBS. In the European Union, 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. In Europe, setmelanotide should be prescribed and supervised by a physician with expertise in obesity with underlying genetic etiology. Limitations of UseSetmelanotide 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 POMC, PCSK1 or LEPR deficiency, or BBS, including obesity associated with other genetic syndromes and general (polygenic) obesity. ContraindicationPrior serious hypersensitivity to setmelanotide or any of the excipients in IMCIVREE. Serious hypersensitivity reactions (e.g., anaphylaxis) have been reported. WARNINGS AND PRECAUTIONS Skin Pigmentation and Darkening of Pre-Existing Nevi: Generalized increased skin pigmentation and darkening of pre-existing nevi have occurred because of its pharmacologic effect. Full body skin examinations prior to initiation and periodically during treatment should be conducted to monitor pre-existing and new pigmentary lesions. Heart rate and blood pressure monitoring: In Europe, heart rate and blood pressure should be monitored as part of standard clinical practice at each medical visit (at least every 6 months) for patients treated with setmelanotide. Disturbance in Sexual Arousal: Spontaneous penile erections in males and sexual adverse reactions in females have occurred. Patients who have an erection lasting longer than 4 hours should seek emergency medical attention. Depression and Suicidal Ideation: Depression and suicidal ideation have occurred. Patients should be monitored for new onset or worsening depression or suicidal thoughts or behaviors. Consideration should be given to discontinuing setmelanotide 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 setmelanotide. Pediatric Population: The prescribing physician should periodically assess response to setmelanotide therapy. In growing children, the impact of weight loss on growth and maturation should be evaluated. In Europe, the prescribing physician should monitor growth (height and weight) using age- and sex-appropriate growth curves. Risk of Serious Adverse Reactions Due to Benzyl Alcohol Preservative in Neonates and Low Birth Weight Infants: Setmelanotide is not approved for use in neonates or infants. Serious and fatal adverse reactions including “gasping syndrome” can occur in neonates and low birth weight infants treated with benzyl alcohol-preserved drugs. ADVERSE REACTIONSMost common adverse reactions (incidence ≥20%) included skin hyperpigmentation, injection site reactions, nausea, headache, diarrhea, abdominal pain, vomiting, depression, and spontaneous penile erection. USE IN SPECIFIC POPULATIONS Lactation: Not recommended when breastfeeding.To report SUSPECTED ADVERSE REACTIONS, contact Rhythm Pharmaceuticals at +1 (833) 789-6337 or FDA at 1-800-FDA-1088 or 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 U.S. Prescribing Information and EU Summary of Product Characteristics 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 potential, safety, efficacy, and regulatory and clinical progress, potential regulatory submissions, approvals and timing thereof of setmelanotide and other product candidates; the timing of results from our global Phase 3 trial evaluating setmelanotide in patients with acquired hypothalamic obesity; the planned new substudy to the ongoing Phase 3 trial evaluating setmelanotide in patients with acquired hypothalamic obesity that would add and evaluate patients with congenital hypothalamic obesity and the timing of enrollment for the substudy; the potential benefits of any of the Company’s products or product candidates for any specific disease indication or at any dosage, including the potential benefits of setmelanotide for patients with acquired hypothalamic obesity or congenital hypothalamic obesity, POMC, PCSK1, or LEPR variants or genetically confirmed Bardet-Biedl syndrome (BBS); expectations surrounding potential clinical trial results, regulatory submissions and approvals; our participation in upcoming events and presentations, the content thereof 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, 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, 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 discussed under the caption “Risk Factors” in Rhythm’s Quarterly Report on Form 10-Q for the three months ended September 30, 2024 and other filings with the Securities and Exchange Commission. 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 Contact:David ConnollyHead of Investor Relations and Corporate CommunicationsRhythm Pharmaceuticals, Inc.857-264-4280dconnolly@rhythmtx.com Media Contact:Sheryl SeapyReal Chemistry(949) 903-4750sseapy@realchemistry.com

- Participants from the completed Phase 2 hypothalamic obesity trial reported positive changes in sleep, energy levels during setmelanotide therapy in qualitative interviews - - Separate analysis of patients across MC4R pathway diseases showed one year of treatment with setmelanotide improved NIH, WHO weight classifications - - Previously reported stage one results from Phase 2 DAYBREAK trial showed potential setmelanotide efficacy in multiple MC4R pathway variants; stage two data expected in Q3 2024 - - Preclinical data demonstrated potential of RM-718 to reduce body weight and hunger - - Additional posters feature design of Phase 1 trial of RM-718 and real-world RESTORE study - BOSTON, June 03, 2024 (GLOBE NEWSWIRE) -- Rhythm Pharmaceuticals, Inc. (Nasdaq: RYTM), a global commercial-stage biopharmaceutical company focused on transforming the lives of patients and their families living with rare neuroendocrine diseases, today announced the presentation of the first patient and caregiver reported experiences from qualitative interviews following the completion of a Phase 2 trial that evaluated treatment with setmelanotide in hypothalamic obesity (HO). These results were among six Rhythm presentations at the Endocrine Society Annual Meeting & Expo (ENDO 2024) being held June 1-4 in Boston. “We continue to advance what we believe to be the most comprehensive clinical research program ever initiated for the treatment of hyperphagia and severe obesity associated with rare melanocortin-4 receptor (MC4R) pathway diseases,” said David Meeker, M.D., Chair, President and Chief Executive Officer of Rhythm. “For the first time, we presented patient and caregiver reported results showing that setmelanotide therapy in patients with hypothalamic obesity was associated with meaningful improvements in their lives beyond clinical outcomes and reductions in body mass index (BMI).” Christian Roth, M.D., Seattle Children’s Research Institute and Division of Endocrinology, Department of Pediatrics, University of Washington, presented, “Patient- and Caregiver-reported Experiences of Hunger, Weight and Energy in Acquired Hypothalamic Obesity Before and During Setmelanotide Therapy.” In qualitative interviews before setmelanotide therapy, five participants (three patients, two caregivers) all reported experiencing substantial weight gain, unrelenting hunger, drastically reduced energy or physical activity, and interrupted nighttime sleep, primarily due to hunger associated with acquired hypothalamic obesity. In their experiences following initiation of setmelanotide therapy, all study participants reported improved energy and ability and desire to be more active, and four of five participants reported reductions in hunger, positive changes in eating behavior and improvements in sleep. Rhythm and its collaborators also delivered two rapid-fire oral presentations and accompanying posters at ENDO 2024: Dr. Roth presented results from an analysis of the clinical characteristics of 58 individuals who participated in trials of setmelanotide across MC4R pathway diseases including hypothalamic obesity, proopiomelanocortin (POMC) or leptin receptor (LEPR) deficiency obesities, or Bardet-Biedl syndrome (BBS). After one year of treatment with setmelanotide, improvements of at least one obesity class were observed across all cohorts (HO: 92%; POMC deficiency: 89%; LEPR deficiency: 36%; BBS: 42%). Patients with LEPR deficiency and BBS had more severe weight categories at baseline but still showed general improvement in weight categories after one year of treatment.Danica Grujic, Ph.D., Senior Director, Non-Clinical Development, Translational Research & Development, Rhythm Pharmaceuticals, presented results from a preclinical study that evaluated treatment with RM-718, a selective MC4R agonist designed to be administered weekly with potential to avoid MC1R-related hyperpigmentation, in a rodent model of obesity, hyperphagia, and insulin resistance. Treatment was well-tolerated and stable weight and food intake reductions and improved insulin sensitivity were observed after three weeks. Rhythm and its collaborators also presented three additional posters at ENDO 2024: Elif Oral, M.D., Associate Professor in the Division of Metabolism, Endocrinology and Diabetes (MEND) at The University of Michigan, presented previously reported stage one results from the two-stage, double-blind, placebo-controlled DAYBREAK trial that show potential setmelanotide efficacy in individuals who carry variants in SEMA3[A-G], PLXNA[1-4], PHIP, TBX3, MAGEL2, or SIM1. At least one patient in each of those cohorts achieved ≥10% body mass index (BMI) reduction at the end of the 16-week, open-label run-in period. Overall, 49 responders were randomized into stage two, which is a 24-week, double-blind, randomized, placebo-controlled period. Setmelanotide was well tolerated with no new safety concerns.Dr. Roth presented the design of Rhythm’s first-in-human Phase 1 trial of once-weekly RM-718 in individuals with obesity or patients with HO.Caroline Huber, Director, Value & Evidence, Rhythm Pharmaceuticals, presented the design of Real-world Evidence of SeTmelanotide fOr Hyperphagia and ChRonic Weight ManagEment (RESTORE), the first study to assess the real-world effectiveness of setmelanotide to provide a greater understanding of patient outcomes, such as hyperphagia and quality of life, in a clinical practice setting. About Rhythm PharmaceuticalsRhythm 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) for chronic weight management in adult and pediatric patients 6 years of age and older with monogenic or syndromic obesity due to pro-opiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1) or leptin receptor (LEPR) deficiency confirmed by genetic testing, or patients with a clinical diagnosis of Bardet-Biedl syndrome (BBS). Both the European Commission (EC) and the UK’s Medicines & Healthcare Products Regulatory Agency (MHRA) have authorized setmelanotide 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. Additionally, Rhythm is advancing a broad clinical development program for setmelanotide in other rare diseases, as well as investigational MC4R agonists LB54640 and RM-718, and a preclinical suite of small molecules for the treatment of congenital hyperinsulinism. Rhythm’s headquarters is in Boston, MA. Setmelanotide IndicationIn the United States, setmelanotide is indicated for chronic weight management in adult and pediatric patients 6 years of age and older with monogenic or syndromic obesity due to POMC, PCSK1 or 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 BBS. In the European Union and 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 6 years of age and above. In the European Union and United Kingdom, setmelanotide should be prescribed and supervised by a physician with expertise in obesity with underlying genetic etiology. Limitations of UseSetmelanotide 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 benignOther types of obesity not related to POMC, PCSK1 or LEPR deficiency, or BBS, including obesity associated with other genetic syndromes and general (polygenic) obesity. ContraindicationPrior serious hypersensitivity to setmelanotide or any of the excipients in IMCIVREE. Serious hypersensitivity reactions (e.g., anaphylaxis) have been reported. WARNINGS AND PRECAUTIONS Skin Pigmentation and Darkening of Pre-Existing Nevi: Generalized increased skin pigmentation and darkening of pre-existing nevi have occurred because of its pharmacologic effect. Full body skin examinations prior to initiation and periodically during treatment should be conducted to monitor pre-existing and new pigmentary lesions. Heart rate and blood pressure monitoring: In Europe, heart rate and blood pressure should be monitored as part of standard clinical practice at each medical visit (at least every 6 months) for patients treated with setmelanotide. Disturbance in Sexual Arousal: Spontaneous penile erections in males and sexual adverse reactions in females have occurred. Patients who have an erection lasting longer than 4 hours should seek emergency medical attention. Depression and Suicidal Ideation: Depression and suicidal ideation have occurred. Patients should be monitored for new onset or worsening depression or suicidal thoughts or behaviors. Consideration should be given to discontinuing setmelanotide 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 setmelanotide. Pediatric Population: The prescribing physician should periodically assess response to setmelanotide therapy. In growing children, the impact of weight loss on growth and maturation should be evaluated. In Europe, the prescribing physician should monitor growth (height and weight) using age- and sex-appropriate growth curves. Risk of Serious Adverse Reactions Due to Benzyl Alcohol Preservative in Neonates and Low Birth Weight Infants: Setmelanotide is not approved for use in neonates or infants. Serious and fatal adverse reactions including “gasping syndrome” can occur in neonates and low birth weight infants treated with benzyl alcohol-preserved drugs. ADVERSE REACTIONS Most common adverse reactions (incidence ≥20%) included skin hyperpigmentation, injection site reactions, nausea, headache, diarrhea, abdominal pain, vomiting, depression, and spontaneous penile erection. USE IN SPECIFIC POPULATIONS Lactation: Not recommended when breastfeeding. REPORTING OF SIDE EFFECTS If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in the package leaflet. You can also contact Rhythm Pharmaceuticals at +1 (833) 789-6337. To report directly via the Yellow Card Scheme please do so via: www.mhra.gov.uk/yellowcard. To report directly to the FDA contact 1-800-FDA-1088 or www.fda.gov/medwatch. [See section 4.8 of the Summary of Product Characteristics for information on reporting suspected adverse reactions in Europe.] By reporting side effects, you can help provide more information on the safety of this medicine. Please see the Summary of Product Characteristics and full Prescribing Information for additional Important Safety Information. Forward-looking StatementsThis 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 Company’s participation in and the content of its presentations at conferences including the ENDO 2024 conference; the promise and potential impact of the Company’s preclinical or clinical trial data; the initiation, timing, design, or results of any clinical trials or readouts; and the potential benefits of any of the Company’s products or product candidates for any specific disease indication or at any dosage, including the potential for setmelanotide to treat hyperphagia and severe obesity associated with melanocortin-4 receptor (MC4R) pathway diseases and additional genetic indications, as well as improve patient and caregiver quality of life, and the potential for RM-718 to reduce body weight and hunger and treat obesity. 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 ability to achieve necessary regulatory approvals, risks associated with data analysis and reporting, failure to identify and develop additional product candidates, 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, the impact of competition, risks relating to product liability lawsuits, inability to maintain collaborations, or the failure of these collaborations, our reliance on third parties, risks relating to intellectual property, our ability to hire and retain necessary personnel, general economic conditions, and the other important factors discussed under the caption “Risk Factors” in our Quarterly Report on Form 10-Q for the three months ended March 31, 2024 and our other filings with the Securities and Exchange Commission. 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 Contact:David ConnollyHead of Investor Relations and Corporate CommunicationsRhythm Pharmaceuticals, Inc.857-264-4280dconnolly@rhythmtx.com Media Contact:Adam DaleyBerry & Company Public Relations212-253-8881adaley@berrypr.com

TNX-2900 is a proprietary magnesium-potentiated formulation of intranasal oxytocin, a naturally occurring hormone that reduces appetite and eating Prader Willi syndrome is the most common genetic cause of life-threatening childhood obesity March 25, 2024 -- Tonix Pharmaceuticals Holding Corp. (Nasdaq: TNXP) (Tonix or the Company), a biopharmaceutical company with marketed products and a pipeline of development candidates, today announced the U.S. Food and Drug Administration (FDA) has granted Rare Pediatric Disease Designation to TNX-2900* (intranasal potentiated oxytocin), a proprietary magnesium (Mg2+)-potentiated formulation of intranasal oxytocin, to treat Prader-Willi syndrome (PWS) in children and adolescents. TNX-2900 was previously granted Orphan Drug designation by the FDA in 2022 for the treatment of PWS and the investigational new drug (IND) application was cleared by the FDA in 2023. The Company may be eligible to receive a transferable Priority Review Voucher if TNX-2900 for PWS is approved for marketing. Recently, vouchers have sold for approximately $100 million. “The Rare Pediatric Disease Designation is an important regulatory milestone in the development of TNX-2900. With PWS being the most common genetic cause of life-threatening childhood obesity, we are excited that the FDA has recognized this significant unmet need in children and adolescents, particularly for PWS hyperphagia, which currently has no approved treatments1,2,” said Seth Lederman, M.D., Chief Executive Officer of Tonix Pharmaceuticals. “As PWS is a genetic disorder associated with abnormalities of the oxytocin system, Tonix believes TNX-2900’s unique formulation has the potential to improve intranasal oxytocin’s therapeutic action by addressing limitations in efficacy observed at high-dose intranasal oxytocin that is not Mg2+-potentiated3,4.” The FDA defines a rare pediatric disease as a serious or life-threating disease that primarily affects individuals aged from birth to 18 years and affects under 200,000 people in the United States. The FDA’s Rare Pediatric Disease Priority Voucher Program is intended to encourage the development of new drugs to treat certain rare pediatric diseases. Under the FDA’s Rare Pediatric Disease Designation and Voucher Program, if TNX-2900 is approved for marketing, Tonix may qualify for a priority review voucher that can be redeemed to receive priority review of a subsequent marketing application for a different product. Priority review vouchers may also be sold or transferred to another sponsor. The new sponsor can redeem the voucher to receive priority review for a different product, which reduces the review time of NDAs from 10 months to six months. There is no limit on the number of times a priority review voucher can be transferred. A 2020 U.S. Government Accounting Office analysis5 of the voucher program found that in the ten years since launch of the program in 2009, the price of buying priority review vouchers ranged from $67 million to $350 million. More recently, priority review vouchers were acquired by Novo Nordisk for $110 million in June of 2022, and by Novartis for $100 million from Marinus in July of 2022.6 Bluebird Bio sold vouchers for $102 million, $95 million and $103 million in November 2022, January 2023, and October 2023, respectively.7-9 In June of 2023, Novartis bought a priority review voucher from Pharming for $21 million, a price that had been negotiated as part of a purchase agreement when Pharming acquired the asset from Novartis.5 PWS is recognized as the most common genetic cause of life-threatening childhood obesity and affects males and females with equal frequency and all races and ethnicities. PWS results from the absence of expression of a group of genes on the paternally acquired chromosome 15. The hallmarks of PWS are lack of suckling in newborns and, in children and adolescents, severe hyperphagia – an overriding physiological drive to eat, leading to severe obesity and other complications associated with significant mortality. A systematic review of the morbidity and mortality as a consequence of hyperphagia in PWS found that the average age of death in PWS was 22.1 years.10 There is no approved medication to treat poor feeding in newborns or hyperphagia in children and adolescents with PWS. Given the serious or life-threatening manifestations of these conditions, there is a critical need for effective treatments to decrease morbidity and mortality, improve quality of life, and increase life expectancy in people with PWS. Oxytocin has potent effects in correcting behavioral characteristics of the Magel2 knock-out mouse model for PWS and autism.11-13 Six clinical trials have investigated intranasal oxytocin as a treatment in pediatric patients with PWS. Four studies showed evidence for improvement in PWS-related behaviors/symptoms14-17; three clinical studies reported evidence for improvement in hyperphagia14,15,17; and one clinical study showed an improvement in sucking in infants16. TNX-2900 is based on Tonix’s patented intranasal Mg2+-potentiated oxytocin formulation intended for use by children and adolescents. This formulation is believed to enhance the potency of oxytocin as well as increase specificity for oxytocin receptors relative to vasopressin receptors, potentially reducing unwanted side effects from activating vasopressin receptors. Tonix is also developing a different intranasal formulation, designated TNX-1900 for adolescent obesity, binge eating disorder, bone health in autism, and social anxiety disorder. Oxytocin is a naturally occurring human hormone that acts as a neurotransmitter in the brain. Oxytocin is believed to be more than 600 million years old and is present in vertebrates including mammals, birds, reptiles, amphibians, and fish.18 It was initially approved by the U.S. Food and Drug Administration as Pitocin®**, an intravenous infusion or intramuscular injection drug, for use in pregnant women to induce labor and control postpartum bleeding or hemorrhage. An intranasal formulation of oxytocin is marketed in some European countries to assist in breast milk production as Syntocinon®*** (oxytocin nasal 40 units/ml). Tonix is a biopharmaceutical company focused on developing, licensing and commercializing therapeutics to treat and prevent human disease and alleviate suffering. Tonix’s development portfolio is focused on central nervous system (CNS) disorders. Tonix’s priority is to submit a New Drug Application (NDA) to the FDA in the second half of 2024 for Tonmya, a product candidate for which two positive Phase 3 studies have been completed for the management of fibromyalgia. TNX-102 SL is also being developed to treat acute stress reaction as well as fibromyalgia-type Long COVID. Tonix’s CNS portfolio includes TNX-1300 (cocaine esterase) a biologic designed to treat cocaine intoxication with Breakthrough Therapy designation. Tonix’s immunology development portfolio consists of biologics to address organ transplant rejection, autoimmunity and cancer, including TNX-1500, which is a humanized monoclonal antibody targeting CD40-ligand (CD40L or CD154) being developed for the prevention of allograft rejection and for the treatment of autoimmune diseases. Tonix also has product candidates in development in the areas of rare disease and infectious disease. Tonix Medicines, our commercial subsidiary, markets Zembrace® SymTouch® (sumatriptan injection) 3 mg and Tosymra® (sumatriptan nasal spray) 10 mg for the treatment of acute migraine with or without aura in adults. Tonix’s product development candidates are investigational new drugs or biologics and have not been approved for any indication. Tonmya™ is conditionally accepted by the U.S. Food and Drug Administration as the tradename for TNX-102 SL for the management of fibromyalgia. Meyerowitz JG, et al. Nat Struct Mol Biol. 2022. 29(3):274-281. Meziane H, et al. Biol Psychiatry. 2015. 78(2):85-94. Correa-da-Silva F, et al. J Neuroendocrinol. 2021. 33(7):e12994. Bharadwaj VN, et al. Pharmaceutics. 2022. 14(5):1105. U.S. Government Accounting Office, Jan 31, 2020. “Drug Development: FDA's Priority Review Voucher Programs”. GAO-20-251. https://www.gao.gov/products/gao-20-251. Waldron, J. Fierce Biotech. June 1, 2023. “Novartis buys priority review voucher from Pharming for discount price of $21 M.” www.fiercebiotech.com/biotech/novartis-buys-priority-review-voucher-pharming-discount-price-21m BlueBird bio Press Release. Nov. 30, 2022 “bluebird bio Sells Priority Review Voucher for $102 Million”. https://investor.bluebirdbio.com/news-releases/news-release-details/bluebird-bio-sells-priority-review-voucher-102-million Kansteiner, F. Fierce Pharma. Jan 6, 2023 “Bluebird scores $95M nest egg after selling second FDA priority review voucher to BMS”. http://www.fiercepharma.com/pharma/bluebird-scores-another-nest-egg-after-selling-second-fda-review-voucher-bms-95m Business Wire. October 30, 2023. “bluebird bio Enters into Advance Agreement to Sell Priority Review Voucher, if Granted, for $103 Million.” http://finance.yahoo.com/news/bluebird-bio-enters-advance-agreement-120000768.html Bellis SA, et al. Eur J Med Genet. 2022. 65(1):104379. Bertoni A, et al. Mol Psychiatry. 2021. 26(12):7582-7595. Schaller F, et al. Hum Mol Genet. 2010. 19:4895-4905. Meziane H, et al. Biol Psychiatry. 2015. 78: 85-94. Kuppens RJ, et al. Clin Endocrinol. 2016. 85:979-987. Miller JL et al. Am J Med Genet A. 2017. 173: 1243-1250. Tauber M, et al. Pediatrics. 2017. 139(2):e20162976. Damen L, et al. Clin Endocrinol. 2020. 94:774-785. Gruber CW. Exp Physiol. 2014. 99(1):55-61. doi: 10.1113/expphysiol.2013.072561. The content above comes from the network. if any infringement, please contact us to modify.