Rhythm Pharmaceuticals Targeting MC4R pathway and transforming the care of patients with rare genetic diseases of obesity May 2021 ® © Rhythm® Pharmaceuticals, Inc. All rights reserved. Forward Looking Statements 2 This presentation contains certain statements that are forward-looking within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, and that involve risks and uncertainties, including without limitations statement ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2021 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38223 RHYTHM PHARMACEUTICALS, INC. (Exact name of registrant as specified in its charter) (State or other jurisdiction of ...

Washington, D.C. 20549 Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION FORM 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38223 RHYTHM PHARMACEUTICALS, INC. (Exact name of registrant as specified in its charter) (State or other jurisdiction of (I.R ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38223 RHYTHM PHARMACEUTICALS, INC. (Exact name of registrant as specified in its charter) (State or other jurisdictio ...

Rhythm Pharmaceuticals Targeting MC4R pathway and transforming the care of patients with rare genetic disorders of obesity August 2020 ® © Rhythm® Pharmaceuticals, Inc. All rights reserved. Forward Looking Statements ® 2 This presentation contains certain statements that are forward-looking within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, and that involve risks and uncertainties, including without limitations sta ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38223 RHYTHM PHARMACEUTICALS, INC. (Exact name of registrant as specified in its charter) (State or other jurisdiction of ...

Rhythm Pharmaceuticals Targeting MC4R pathway and transforming the care of patients with rare genetic disorders of obesity June 2020 ® © Rhythm® Pharmaceuticals, Inc. All rights reserved. Forward Looking Statements ® 2 This presentation contains certain statements that are forward-looking within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, and that involve risks and uncertainties, including statements regarding Rhyt ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2020 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38223 RHYTHM PHARMACEUTICALS, INC. (Exact name of registrant as specified in its charter) Delaware 46‑2159271 (State or o ...

Table of Contents ' UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38223 RHYTHM PHARMACEUTICALS, INC. (Exact name of registrant as specified in its charter) (State or other jurisdiction of (I ...

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2019 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission file number 001-38223 RHYTHM PHARMACEUTICALS, INC. (Exact name of registrant as specified in its charter) Delaware 46‑2159271 (State ...