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The securities were sold in multiple transactions at prices ranging from $105.00 to $105.31 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":239258,"source":{"system":"sec-edgar","filing":"0001649904-26-000026","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":6,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000026/form4.xml","form_type":"4"}},{"id":4617529,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":36265,"kind":"person","name":"Meeker David P","position":1,"cik":"0001385155","reported_name":"Meeker David P","relationship":{"director":true,"officer":true,"officer_title":"President and CEO"}}],"security":"Common Stock","published_at":"2026-09-14T23:37:32.000Z","date":"2026-09-14","kind":"sale","planned":true,"acquired":false,"shares":1817,"price":104.5487,"value":189964.9879,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 15, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F6","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $103.97 to $104.94 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":241558,"source":{"system":"sec-edgar","filing":"0001649904-26-000026","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000026/form4.xml","form_type":"4"}},{"id":4617528,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":36265,"kind":"person","name":"Meeker David P","position":1,"cik":"0001385155","reported_name":"Meeker David P","relationship":{"director":true,"officer":true,"officer_title":"President and CEO"}}],"security":"Common Stock","published_at":"2026-09-14T23:37:32.000Z","date":"2026-09-14","kind":"sale","planned":true,"acquired":false,"shares":8698,"price":103.43,"value":899634.14,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 15, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $102.97 to $103.96 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":243375,"source":{"system":"sec-edgar","filing":"0001649904-26-000026","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000026/form4.xml","form_type":"4"}},{"id":4617527,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":36265,"kind":"person","name":"Meeker David P","position":1,"cik":"0001385155","reported_name":"Meeker David P","relationship":{"director":true,"officer":true,"officer_title":"President and CEO"}}],"security":"Common Stock","published_at":"2026-09-14T23:37:32.000Z","date":"2026-09-14","kind":"sale","planned":true,"acquired":false,"shares":30746,"price":102.347,"value":3146760.862,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 15, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $101.96 to $102.94 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":252073,"source":{"system":"sec-edgar","filing":"0001649904-26-000026","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000026/form4.xml","form_type":"4"}},{"id":4617526,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":36265,"kind":"person","name":"Meeker David P","position":1,"cik":"0001385155","reported_name":"Meeker David P","relationship":{"director":true,"officer":true,"officer_title":"President and CEO"}}],"security":"Common Stock","published_at":"2026-09-14T23:37:32.000Z","date":"2026-09-14","kind":"sale","planned":true,"acquired":false,"shares":6439,"price":101.7464,"value":655145.0696,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 15, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $100.96 to $101.95 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":282819,"source":{"system":"sec-edgar","filing":"0001649904-26-000026","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000026/form4.xml","form_type":"4"}},{"id":4617525,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":36265,"kind":"person","name":"Meeker David P","position":1,"cik":"0001385155","reported_name":"Meeker David P","relationship":{"director":true,"officer":true,"officer_title":"President and CEO"}}],"security":"Common Stock","published_at":"2026-09-14T23:37:32.000Z","date":"2026-09-14","kind":"exercise","planned":true,"acquired":true,"shares":50000,"price":6.05,"value":302500.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 15, 2026."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 242 shares acquired under the Rhythm Pharmaceuticals, Inc. employee stock purchase plan on 2-28-2026."}],"balance_after":289258,"source":{"system":"sec-edgar","filing":"0001649904-26-000026","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000026/form4.xml","form_type":"4"}},{"id":670850,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":17845,"kind":"person","name":"Smith Hunter C","position":1,"cik":"0001636385","reported_name":"Smith Hunter C","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Employee Stock Option (Right to Buy)","published_at":"2026-09-01T20:22:52.000Z","date":"2026-08-31","kind":"exercise","planned":true,"acquired":false,"shares":57187,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 13, 2026."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F5","text":"This option was granted on February 14, 2018 and the shares underlying this option vested in sixteen equal quarterly installments."}],"balance_after":3813,"derivative":{"exercise_price":25.79,"expiration_date":"2028-02-13","underlying":"Common Stock","underlying_shares":57187},"source":{"system":"sec-edgar","filing":"0001649904-26-000023","document":"form4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1636385/000164990426000023/form4.xml","form_type":"4"}},{"id":670849,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":17845,"kind":"person","name":"Smith Hunter C","position":1,"cik":"0001636385","reported_name":"Smith Hunter C","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2026-09-01T20:22:52.000Z","date":"2026-08-31","kind":"sale","planned":true,"acquired":false,"shares":28188,"price":106.2029,"value":2993647.3452,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 13, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $106.05 to $106.88 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":114024,"source":{"system":"sec-edgar","filing":"0001649904-26-000023","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1636385/000164990426000023/form4.xml","form_type":"4"}},{"id":670848,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":17845,"kind":"person","name":"Smith Hunter C","position":1,"cik":"0001636385","reported_name":"Smith Hunter C","relationship":{"officer":true,"officer_title":"Chief Financial Officer"}}],"security":"Common Stock","published_at":"2026-09-01T20:22:52.000Z","date":"2026-08-31","kind":"sale","planned":true,"acquired":false,"shares":11514,"price":105.3702,"value":1213232.4828,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on May 13, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $105.04 to $106.01 per common stock. 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The securities were sold in multiple transactions at prices ranging from $104.04 to $105.03 per common stock. 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shares subject to the option on the first anniversary of the grant date and as to 6.25% of the total number of shares subject to the option upon the Reporting Person's completion of each successive three months of service to the Corporation."}],"balance_after":50000,"derivative":{"exercise_price":115.44,"expiration_date":"2036-08-16","underlying":"Common Stock","underlying_shares":50000},"source":{"system":"sec-edgar","filing":"0001649904-26-000020","document":"form4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000020/form4.xml","form_type":"4"}},{"id":685117,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":22763,"kind":"person","name":"Shulman Joseph","position":1,"cik":"0001909855","reported_name":"Shulman Joseph","relationship":{"officer":true,"officer_title":"Chief Technical Officer"}}],"security":"Stock Options 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The options vested and become exercisable in 16 substantially equal installments upon the Reporting Person's completion of each three full months of successive service to the Issuer following the grant date."}],"balance_after":5945,"derivative":{"exercise_price":6.8,"expiration_date":"2032-02-08","underlying":"Common Stock","underlying_shares":2024},"source":{"system":"sec-edgar","filing":"0001649904-26-000015","document":"form4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000015/form4.xml","form_type":"4"}},{"id":685116,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":22763,"kind":"person","name":"Shulman Joseph","position":1,"cik":"0001909855","reported_name":"Shulman Joseph","relationship":{"officer":true,"officer_title":"Chief Technical Officer"}}],"security":"Common Stock","published_at":"2026-08-17T22:00:24.000Z","date":"2026-08-13","kind":"sale","planned":true,"acquired":false,"shares":5079,"price":119.75,"value":608210.25,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The Exercise and sale reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 15, 2025."}],"balance_after":15915,"source":{"system":"sec-edgar","filing":"0001649904-26-000015","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000015/form4.xml","form_type":"4"}},{"id":685115,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":22763,"kind":"person","name":"Shulman Joseph","position":1,"cik":"0001909855","reported_name":"Shulman Joseph","relationship":{"officer":true,"officer_title":"Chief Technical Officer"}}],"security":"Common Stock","published_at":"2026-08-17T22:00:24.000Z","date":"2026-08-13","kind":"exercise","planned":true,"acquired":true,"shares":2024,"price":6.8,"value":13763.2,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The Exercise and sale reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 15, 2025."}],"balance_after":20994,"source":{"system":"sec-edgar","filing":"0001649904-26-000015","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000015/form4.xml","form_type":"4"}},{"id":685791,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":22964,"kind":"person","name":"Garfield Alastair","position":1,"cik":"0002027261","reported_name":"Garfield Alastair","relationship":{"officer":true,"officer_title":"Chief Scientific Officer"}}],"security":"Common Stock","published_at":"2026-08-17T21:57:29.000Z","date":"2026-08-13","kind":"sale","planned":true,"acquired":false,"shares":800,"price":119.1688,"value":95335.04,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in the Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 14, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $118.73 to $119.52 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":2295,"source":{"system":"sec-edgar","filing":"0001649904-26-000013","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/2027261/000164990426000013/form4.xml","form_type":"4"}},{"id":685790,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":22964,"kind":"person","name":"Garfield Alastair","position":1,"cik":"0002027261","reported_name":"Garfield Alastair","relationship":{"officer":true,"officer_title":"Chief Scientific Officer"}}],"security":"Common Stock","published_at":"2026-08-17T21:57:29.000Z","date":"2026-08-13","kind":"sale","planned":true,"acquired":false,"shares":3400,"price":118.2843,"value":402166.62,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in the Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 14, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $117.73 to $118.71 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":3095,"source":{"system":"sec-edgar","filing":"0001649904-26-000013","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/2027261/000164990426000013/form4.xml","form_type":"4"}},{"id":685789,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":22964,"kind":"person","name":"Garfield Alastair","position":1,"cik":"0002027261","reported_name":"Garfield Alastair","relationship":{"officer":true,"officer_title":"Chief Scientific Officer"}}],"security":"Common Stock","published_at":"2026-08-17T21:57:29.000Z","date":"2026-08-13","kind":"sale","planned":true,"acquired":false,"shares":1556,"price":117.0759,"value":182170.1004,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in the Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 14, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $116.72 to $117.66 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":6495,"source":{"system":"sec-edgar","filing":"0001649904-26-000013","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/2027261/000164990426000013/form4.xml","form_type":"4"}},{"id":685788,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":22964,"kind":"person","name":"Garfield Alastair","position":1,"cik":"0002027261","reported_name":"Garfield Alastair","relationship":{"officer":true,"officer_title":"Chief Scientific Officer"}}],"security":"Common Stock","published_at":"2026-08-17T21:57:29.000Z","date":"2026-08-13","kind":"sale","planned":true,"acquired":false,"shares":2007,"price":116.1093,"value":233031.3651,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The sales reported in the Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 14, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $115.67 to $116.62 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":8051,"source":{"system":"sec-edgar","filing":"0001649904-26-000013","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/2027261/000164990426000013/form4.xml","form_type":"4"}},{"id":686982,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23364,"kind":"person","name":"Lee Jennifer Kayden","position":1,"cik":"0001801372","reported_name":"Lee Jennifer Kayden","relationship":{"officer":true,"officer_title":"EVP, Head of North America"}}],"security":"Stock Options (Right to Buy)","published_at":"2026-08-14T23:04:44.000Z","date":"2026-08-13","kind":"exercise","planned":true,"acquired":false,"shares":21601,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercises and sales reported in the Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 14, 2026."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F3","text":"The stock options were granted on February 9, 2022. The options vested and became exercisable in 16 substantially equal installments upon the Reporting Person's completion of each three full months of successive service to the Issuer following the grant date."}],"balance_after":0,"derivative":{"exercise_price":6.8,"expiration_date":"2032-02-08","underlying":"Common Stock","underlying_shares":21601},"source":{"system":"sec-edgar","filing":"0001649904-26-000009","document":"form4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1801372/000164990426000009/form4.xml","form_type":"4"}},{"id":686981,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23364,"kind":"person","name":"Lee Jennifer Kayden","position":1,"cik":"0001801372","reported_name":"Lee Jennifer Kayden","relationship":{"officer":true,"officer_title":"EVP, Head of North America"}}],"security":"Stock Options (Right to 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The options vest and become exercisable in 16 substantially equal installments upon the Reporting Person's completion of each three full months of successive service to the Issuer following the grant date."}],"balance_after":35875,"derivative":{"exercise_price":6.8,"expiration_date":"2032-02-08","underlying":"Common Stock","underlying_shares":46625},"source":{"system":"sec-edgar","filing":"0001649904-26-000007","document":"form4.xml","document_sequence":1,"table":"derivative","row_type":"transaction","position":8,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000007/form4.xml","form_type":"4"}},{"id":686464,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23226,"kind":"person","name":"Mazabraud Yann","position":1,"cik":"0001774702","reported_name":"Mazabraud Yann","relationship":{"officer":true,"officer_title":"EVP, Head of International"}}],"security":"Common Stock","published_at":"2026-08-14T23:01:59.000Z","date":"2026-08-12","kind":"sale","planned":true,"acquired":false,"shares":17319,"price":117.4686,"value":2034438.6834,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F7","text":"The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $117.01 to $117.60 per share. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":55655,"source":{"system":"sec-edgar","filing":"0001649904-26-000007","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":7,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000007/form4.xml","form_type":"4"}},{"id":686463,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23226,"kind":"person","name":"Mazabraud Yann","position":1,"cik":"0001774702","reported_name":"Mazabraud Yann","relationship":{"officer":true,"officer_title":"EVP, Head of International"}}],"security":"Common Stock","published_at":"2026-08-14T23:01:59.000Z","date":"2026-08-12","kind":"sale","planned":true,"acquired":false,"shares":18208,"price":116.4941,"value":2121124.5728,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F6","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $116.01 to $117.00 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":72974,"source":{"system":"sec-edgar","filing":"0001649904-26-000007","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":6,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000007/form4.xml","form_type":"4"}},{"id":686462,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23226,"kind":"person","name":"Mazabraud Yann","position":1,"cik":"0001774702","reported_name":"Mazabraud Yann","relationship":{"officer":true,"officer_title":"EVP, Head of International"}}],"security":"Common Stock","published_at":"2026-08-14T23:01:59.000Z","date":"2026-08-12","kind":"sale","planned":true,"acquired":false,"shares":14568,"price":115.427,"value":1681540.536,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $115.01 to $116.00 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":91182,"source":{"system":"sec-edgar","filing":"0001649904-26-000007","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":5,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000007/form4.xml","form_type":"4"}},{"id":686461,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23226,"kind":"person","name":"Mazabraud Yann","position":1,"cik":"0001774702","reported_name":"Mazabraud Yann","relationship":{"officer":true,"officer_title":"EVP, Head of International"}}],"security":"Common Stock","published_at":"2026-08-14T23:01:59.000Z","date":"2026-08-12","kind":"sale","planned":true,"acquired":false,"shares":3605,"price":114.6955,"value":413477.2775,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $114.01 to $115.00 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":105750,"source":{"system":"sec-edgar","filing":"0001649904-26-000007","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000007/form4.xml","form_type":"4"}},{"id":686460,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23226,"kind":"person","name":"Mazabraud Yann","position":1,"cik":"0001774702","reported_name":"Mazabraud Yann","relationship":{"officer":true,"officer_title":"EVP, Head of International"}}],"security":"Common Stock","published_at":"2026-08-14T23:01:59.000Z","date":"2026-08-12","kind":"sale","planned":true,"acquired":false,"shares":1000,"price":112.856,"value":112856.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F3","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $112.84 to $112.92 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":109355,"source":{"system":"sec-edgar","filing":"0001649904-26-000007","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000007/form4.xml","form_type":"4"}},{"id":686459,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23226,"kind":"person","name":"Mazabraud Yann","position":1,"cik":"0001774702","reported_name":"Mazabraud Yann","relationship":{"officer":true,"officer_title":"EVP, Head of International"}}],"security":"Common Stock","published_at":"2026-08-14T23:01:59.000Z","date":"2026-08-12","kind":"sale","planned":true,"acquired":false,"shares":2300,"price":111.7992,"value":257138.16,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2026."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is a weighted average price. The securities were sold in multiple transactions at prices ranging from $111.58 to $112.30 per common stock. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."}],"balance_after":110355,"source":{"system":"sec-edgar","filing":"0001649904-26-000007","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000007/form4.xml","form_type":"4"}},{"id":686458,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":23226,"kind":"person","name":"Mazabraud Yann","position":1,"cik":"0001774702","reported_name":"Mazabraud Yann","relationship":{"officer":true,"officer_title":"EVP, Head of International"}}],"security":"Common Stock","published_at":"2026-08-14T23:01:59.000Z","date":"2026-08-12","kind":"exercise","planned":true,"acquired":true,"shares":46625,"price":6.8,"value":317050.0,"ownership":{"direct":true},"footnotes":[{"field":"kind","element":"transactionCoding","label":"F1","text":"The exercise and sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 13, 2026."}],"balance_after":112655,"source":{"system":"sec-edgar","filing":"0001649904-26-000007","document":"form4.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1649904/000164990426000007/form4.xml","form_type":"4"}},{"id":718606,"issuer":{"id":3693,"kind":"organization","name":"RHYTHM PHARMACEUTICALS, INC.","symbol":"RYTM"},"owners":[{"id":22964,"kind":"person","name":"Garfield Alastair","position":1,"cik":"0002027261","reported_name":"Garfield Alastair","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"Chief Scientific Officer"}}],"security":"Restricted Stock Units","published_at":"2026-07-02T20:52:49.000Z","date":"2026-07-01","kind":"exercise","planned":false,"acquired":false,"shares":4445,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"derivative.exercise_price","element":"conversionOrExercisePrice","label":"F1","text":"Each restricted stock unit represents a contingent right to receive one share of Issuer common stock."},{"field":"derivative.exercise_date","element":"exerciseDate","label":"F3","text":"The restricted stock units vest as to 25% of the total restricted stock units on each of the first four anniversaries of July 1, 2024, subject to the Reporting Person's continued service on each such vesting date. The restricted stock units have no expiration date."},{"field":"derivative.expiration_date","element":"expirationDate","label":"F3","text":"The restricted stock units vest as to 25% of the total restricted stock units on each of the first four anniversaries of July 1, 2024, subject to the Reporting Person's continued service on each such vesting date. 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