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Rhythm PHARMACEUTICALS Rhythm Pharmaceuticals Reports First Quarter 2021 Financial Results May 3 , 2021 -- First U.S. commercial sales of IMCIVREE ™ M ( setmelanotide ) completed late in first quarter- -- Late - breaking data presentations at ENDO 2021 demonstrated continued weight loss with setmelanotide at up to nine months in HET obesity , as well as weight loss data in adults and BMI - Z reductions in adolescents with Bardet - Biedl syndrome -- -- Delivered proof - of - concept data from Phase 2 Basket Study in HET POMC , PCSK1 or LEPR deficiencies , and obesity due to SRC1 and SH2B1 deficiencies -- -- Closed $ 172.5 million public offering and sold Priority Review Voucher for $ 100 million , providing additional funding to advance continued development of setmelanotide -- BOSTON , May 03 , 2021 ( GLOBE NEWSWIRE ) -- Rhythm Pharmaceuticals , Inc. ( Nasdaq : RYTM ) , a commercial - stage biopharmaceutical company committed to transforming the treatment paradigm for people living with rare genetic diseases of obesity , today reported financial results and provided a business update for the first quarter ended March 31 , 2021 . " This is an exciting time of growth and momentum for Rhythm , as we made several significant steps on our journey to transform the care of patients with rare genetic diseases of obesity and to expand the reach of setmelanotide , " said David Meeker , M.D. , Chair , President and Chief Executive Officer of Rhythm . “ In the first quarter of 2021 , we delivered proof - of - concept data in HET obesity and obesity due to SRC1 or SH2B1 deficiencies , three indications with a combined total addressable population estimated between 100,000 and 200,000 patients in the United States . In addition , we presented compelling Phase 3 data that showed weight loss in adults and BMI - Z reductions in adolescents with Bardet - Biedl syndrome ( BBS ) . We are pleased to have completed our first U.S. commercial sales of IMCIVREE ™ ( setmelanotide ) in the first quarter . " Dr. Meeker continued , “ Looking forward , we anticipate an initial European approval of IMCIVREE in obesity due to POMC , PCSK1 and LEPR deficiency in the second half of 2021 , and we are putting in place the global infrastructure to support commercial availability . We also remain on track to complete U.S. and EU regulatory submissions for BBS in the second half of 2021. In addition , we expect to initiate a pivotal Phase 3 MC4R pathway trial to evaluate setmelanotide in HETS , SRC1 or SH2B1 deficiencies , a new exploratory Phase 2 Basket trial to evaluate setmelanotide's ability to treat patients with genetic variants in one of 31 additional genes , a registrational trial for our weekly formulation of setmelanotide , an exploratory trial in hypothalamic obesity , and a pediatrics trial for patients between 2 and 6 years old . " First Quarter and Recent Business Highlights : Pipeline and Business Developments : • Late in March 2021 , Rhythm completed the first commercial sales of IMCIVREE following U.S. Food and Drug Administration ( FDA ) approval in November 2020. IMCIVREE was approved for chronic weight management in adult and pediatric patients six years of age and older with obesity due to proopiomelanocortin ( POMC ) , proprotein convertase subtilisin / kexin type 1 ( PCSK1 ) or leptin receptor ( LEPR ) deficiency confirmed by genetic testing . • In March 2021 , Rhythm had three late - breaking data presentations from Phase 2 and Phase 3 studies of setmelanotide during the 103rd Annual Meeting and Expo of the Endocrine Society ( ENDO 2021 ) . Sadaf Farooqi , M.D. , Ph.D. , University of Cambridge , UK , presented proof - of - concept data from the Company's Phase 2 study evaluating setmelanotide in individuals living with heterozygous ( HET ) obesity due to genetic variants in one of two alleles of the POMC , PCSK1 or LEPR gene . The oral presentation included new weight loss data that showed patients with HET obesity who were classified as setmelanotide - responsive at three months continued to lose weight as they remained on treatment , with a mean weight loss of 12.3 percent at nine months on therapy . • Additional poster presentations at ENDO 2021 included previously disclosed topline Phase 3 data in BBS and Alström syndromes and new analyses of adverse events in Phase 2 and Phase 3 studies in POMC , PCSK1 , or LEPR deficiency showing consistent safety results for setmelanotide . • Rhythm also presented an encore poster of the topline Phase 3 BBS data at the 2021 Pediatric Endocrine Society Virtual Annual Meeting on April 30 . • In January 2021 , Rhythm announced new proof - of - concept interim data from its ongoing Phase 2 Basket Study across individuals with HET obesity , obesity due to SRC1 deficiency or obesity due to SH2B1 deficiency . Across all three populations , setmelanotide led to meaningful weight loss in approximately 30 percent to greater than 50 percent of treated patients . Rhythm believes that these data , coupled with updated sequencing results , suggest that there are approximately 100,000-200,000 potentially setmelanotide - responsive patients with HET , SRC1 or SH2B1 obesity in the United States . • Also in January 2021 , Rhythm announced that it has leveraged its proprietary gene curation and selection strategy to identify an additional 31 genes with strong or very strong MC4R pathway relevance , paving the way for the Company to