13D Filing: OrbiMed Advisors and Rhythm Pharmaceuticals Inc (RYTM)

Item 1.

Security and Issuer

This Schedule 13D (this “Statement”) relates to the common stock, par value $0.001 per share (the “Shares”), of Rhythm Pharmaceuticals, Inc., a corporation organized under the laws of Delaware (the “Issuer”), with its principal executive offices located at 500 Boylston Street, 11^th floor, Boston, MA 02116.  The common stock is listed on the NASDAQ Global Market under the ticker symbol “RYTM”.  Information given in response to each item shall be deemed incorporated by reference in all other items, as applicable.

On October 10, 2017, the Issuer completed its initial public offering pursuant to which the Issuer agreed to issue and sell to the participants 8,107,500 Shares (the “IPO”).  The purchase price for each Share was $17.00.  As a result of the IPO, the Issuer’s total number of outstanding Shares increased to 27,131,484.

Item 2.

Identity and Background

(a)            This Statement is being filed by OrbiMed Advisors LLC (“Advisors”), a limited liability company organized under the laws of Delaware, OrbiMed Capital GP V LLC (“GP V”), a limited liability company organized under the laws of Delaware, and Samuel D. Isaly (“Isaly”), an individual (collectively, the “Reporting Persons”).

(b) – (c)  Advisors, a registered investment adviser under the Investment Advisers Act of 1940, as amended, is the sole managing member of GP V, which is the sole general partner of OrbiMed Private Investments V, LP (“OPI V”).  OPI V holds Shares as described herein.  Advisors, GP V, and Isaly have their principal offices at 601 Lexington Avenue, 54th Floor, New York, New York 10022.

The directors and executive officers of Advisors and GP V are set forth on Schedules I and II, attached hereto.  Schedules I and II set forth the following information with respect to each such person:

(i)

name;

(ii)

business address;

(iii)

present principal occupation or employment and the name, principal business and address of any corporation or other organization in which such employment is conducted;

(iv)

citizenship.

(d) – (e)   During the last five years, neither the Reporting Persons nor any Person named in Schedule I or II have been (i) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

(f)          Isaly is a citizen of the United States.

Item 3.

Source and Amount of Funds or Other Consideration

On and prior to the close of August 3, 2015, Advisors and GP V, pursuant to their authority under the limited partnership agreement of OPI V, as more particularly referred to in Item 6 below, caused OPI V to purchase 10,937,500 shares of Series A Preferred Stock of the Issuer.  Upon closing of the Issuer’s initial public offering, each share of Series A Preferred Stock converted into Shares on the basis of one Share for each 9.17 shares of Series A Preferred Stock.