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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C.  20549


SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 2)*

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(Name of Issuer)

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(Title of Class of Securities)

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(CUSIP Number)

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

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(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of § 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box ☐.

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits.  See § 240.13d-7(b) for other parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

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(1)

This percentage is calculated based upon 27,530,184 outstanding shares of common stock, par value $0.001 per share (the “Shares”), of Rhythm Pharmaceuticals, Inc. (the “Issuer”), as set forth in the Issuer’s Form 10-Q, filed with the Securities and Exchange Commission on May 14, 2018.

(1)

This percentage is calculated based upon 27,530,184  outstanding shares of common stock, par value $0.001 per share (the “Shares”), of Rhythm Pharmaceuticals, Inc. (the “Issuer”), as set forth in the Issuer’s Form 10-Q, filed with the Securities and Exchange Commission on May 14, 2018.

 

 

Item 1.

Security and Issuer

This Amendment No. 2 (“Amendment No. 2”) to Schedule 13D supplements and amends the Statement on Schedule 13D of OrbiMed Advisors LLC and OrbiMed Capital GP III LLC (the “Statement”) originally filed with the Securities and Exchange Commission (the “SEC”) on October 20, 2017 with Samuel D. Isaly as an additional reporting person, and amended by Amendment No. 1 thereto filed with the SEC on February 7, 2018. The 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 Shares are 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.

This Amendment No. 2 is being filed to report that the beneficial ownership of the outstanding Shares of the Issuer held by the Reporting Persons was reduced by more than one percent following the transactions described in Item 5(c) below.

Item 2.

Identity and Background

(b) – (c), (f) 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 has their principal offices at 601 Lexington Avenue, 54th Floor, New York, New York 10022.

GP V has its 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.

Item 3.

Source and Amount of Funds or Other Consideration

Not applicable.

Item 4.

Purpose of Transaction

This Amendment No. 2 to the Statement relates to the transactions by the Reporting Persons more fully described in Item 5 below. The Shares initially had been acquired by the Reporting Persons for the purpose of making an investment in the Issuer and not with the intention of acquiring control of the Issuer’s business.

The Reporting Persons from time to time intend to review their investment in the Issuer on the basis of various factors, including the Issuer’s business, financial condition, results of operations and prospects, general economic and industry conditions, the securities markets in general and those for the Issuer’s common stock in particular, as well as other developments and other investment opportunities.  Based upon such review, the Reporting Persons will take such actions in the future as the Reporting Persons may deem appropriate in light of the circumstances existing from time to time.  If the Reporting Persons believe that further investment in the Issuer is attractive, whether because of the market price of the common stock or otherwise, they may acquire Shares or other securities of the Issuer either in the open market or in privately negotiated transactions.  Similarly, depending on market and other factors, the Reporting Persons may determine to dispose of some or all of the Shares currently owned by the Reporting Persons or otherwise acquired by the Reporting Persons either in the open market or in privately negotiated transactions.

Except as set forth in this Statement, the Reporting Persons have not formulated any plans or proposals which relate to or would result in: (a) the acquisition by any person of additional securities of the Issuer or the disposition of securities of the Issuer, (b) an extraordinary corporate transaction, such as a merger, reorganization or liquidation, involving the Issuer or any of its subsidiaries, (c) a sale or transfer of a material amount of the assets of the Issuer or any of its subsidiaries, (d) any change in the present Board of Directors or management of the Issuer, including any plans or proposals to change the number or term of directors or to fill any existing vacancies on the board, (e) any material change in the Issuer’s capitalization or dividend policy of the Issuer, (f) any other material change in the Issuer’s business or corporate structure, (g) any change in the Issuer’s charter or bylaws or other instrument corresponding thereto or other action which may impede the acquisition of control of the Issuer by any person, (h) causing a class of the Issuer’s securities to be deregistered or delisted from a national securities exchange or to cease to be authorized to be quoted in an inter-dealer quotation system of a registered national securities association, (i) a class of equity securities of the Issuer becoming eligible for termination of registration pursuant to Section 12(g)(4) of the Act or (j) any action similar to any of those enumerated above.

Item 5.  Interest in Securities of the Issuer

In addition, Advisors and GP V, pursuant to their authority under the limited partnership agreement of OPI V, prior to the date of this filing, caused OPI V to enter into the agreements referred to in Item 6 below.

(c)

Seller	Date of Transaction	Transaction	Number of Shares	Price Per Share*
OPI V	May 18, 2018	Sold	69,136	$30.77
OPI V	May 21, 2018	Sold	62,500	$31.01
OPI V	May 22, 2018	Sold	17,980	$30.38
OPI V	May 22, 2018	Sold	1,600	$30.96
OPI V	May 23, 2018	Sold	36,895	$30.68
OPI V	May 24, 2018	Sold	13,984	$30.24
OPI V	May 31, 2018	Sold	165,100	$32.48
OPI V	May 31, 2018	Sold	18,631	$33.28
OPI V	June 1, 2018	Sold	79,500	$32.60
OPI V	June 1, 2018	Sold	400	$33.31
OPI V	June 4, 2018	Sold	60,369	$32.28
OPI V	June 4, 2018	Sold	200	$33.48

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Except as disclosed above and in Amendment No. 2, the Reporting Persons have not effected any transactions in the Shares during the past sixty (60) days.

 

Item 6.  Contracts, Arrangements, Understandings or Relationship with Respect to Securities of the Issuer

 

In addition to the relationships between the Reporting Persons described in Items 2 and 5 above, GP V is the sole general partner of OPI V, pursuant to the terms of the limited partnership agreement of OPI V. Advisors is the sole managing member of GP V, pursuant to the terms of the limited liability company agreement of GP V. Pursuant to these agreements and relationships, Advisors and GP V have discretionary investment management authority with respect to the assets of OPI V. Such authority includes the power of GP V and Advisors to vote and otherwise dispose of securities purchased by OPI V. The number of outstanding Shares held of record by OPI V is 2,375,000. Advisors and GP V may be considered to hold indirectly 2,375,000 Shares.

 

In addition, OPI V and certain other stockholders of the Issuer entered into an amended and restated investors’ rights agreement with the Issuer (the “Investors Rights Agreement”), dated as of August 21, 2017.  Pursuant to the Investor Rights Agreement and subject to the terms and conditions therein, the parties agreed that:

The Investors Rights Agreement further provides that, in the event that the Issuer determines to register any of its securities under the Securities Act, either for its own account or for the account of other security holders, the stockholders who are party to the Investors Rights Agreement, including OPI V, will be entitled to certain “piggyback” registration rights allowing the holders to include their shares in such registration, subject to certain marketing and other limitations.  The underwriters of any underwritten offering will have the right to limit the number of registrable securities to be included in the registration statement, but such number may not be below 30% of the total number of Shares included in such registration statement.

At any time when the Issuer is eligible to use a Form S-3 registration statement, the holders of at least 10% of the registratable securities then outstanding can request that the Issuer register all or a portion of their Shares on Form S-3, so long as the aggregate price to the public of the securities to be sold under the registration statement on Form S-3 is at least $10.0 million or consists of all the remaining registrable securities, and subject to specified exceptions, conditions and limitations.

Subject to certain limitations, the Issuer will pay the registration expenses of the holders of the shares registered pursuant to the demand, Form S-3 and piggyback registration rights described above.

The Investors Rights Agreement contains customary cross-indemnification provisions, pursuant to which the Issuer is obligated to indemnify the selling stockholders in the event of, among other things, material misstatements or omissions in the registration statement attributable to the Issuer, and the selling stockholders are obligated to indemnify the Issuer for, among other things, material misstatements or omissions attributable to them.

OPI V’s demand, Form S-3 and piggyback registration rights described above generally will terminate upon the earlier of: (i) five years following the closing of the IPO or (ii) such time as SEC Rule 144 or another similar exemption under the Securities Act is available for the sale of all Shares held by OPI V during a three-month period without registration and without the requirement for the Issuer to be in compliance with the current public information required under SEC Rule 144(c)(1).

 

The foregoing description of the Investor Rights Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Investor Rights Agreement, a copy of which is filed as Exhibit 2 and incorporated herein by reference.

Item 7. Materials to Be Filed as Exhibits

Exhibit	Description
1.	Joint Filing Agreement among OrbiMed Advisors LLC and OrbiMed Capital GP V LLC.
2.	Amended and Restated Investors’ Rights Agreement by and among the Issuer and each of the persons listed on Schedule A thereto, dated as of August 21, 2017 (incorporated by reference to Exhibit 4.2 to the Issuer’s Registration Statement on Form S-1 (SEC 333-220337), filed with the SEC on September 5, 2017).

SIGNATURE

After reasonable inquiry and to the best of each of the undersigned’s knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: June 4, 2018

	OrbiMed Advisors LLC
	By:	/s/ Jonathan T. Silverstein
		Name:	Jonathan T. Silverstein
		Title:	Member of OrbiMed Advisors LLC
	By:	/s/ Sven H. Borho
		Name:	Sven H. Borho
		Title:	Member of OrbiMed Advisors LLC
	By:	/s/ Carl L. Gordon
		Name:	Carl L. Gordon
		Title:	Member of OrbiMed Advisors LLC

 

	OrbiMed Capital GP V LLC
	By:	OrbiMed Advisors LLC its Managing Member
	By:	/s/ Jonathan T. Silverstein
		Name:	Jonathan T. Silverstein
		Title:	Member of OrbiMed Advisors LLC
	By:	/s/ Sven H. Borho
		Name:	Sven H. Borho
		Title:	Member of OrbiMed Advisors LLC
	By:	/s/ Carl L. Gordon
		Name:	Carl L. Gordon
		Title:	Member of OrbiMed Advisors LLC

 

Schedule I

 

The name and present principal occupation of each of the executive officers and directors of OrbiMed Advisors LLC are set forth below.  Unless otherwise noted, each of these persons are United States citizens and have as their business address 601 Lexington Avenue, 54th Floor, New York, NY 10022.

 

Name	Position with Reporting Person	Principal Occupation
Carl L. Gordon	Member	Member OrbiMed Advisors LLC
Sven H. Borho German and Swedish Citizen	Member	Member OrbiMed Advisors LLC
Jonathan T. Silverstein	Member	Member OrbiMed Advisors LLC
W. Carter Neild	Member	Member OrbiMed Advisors LLC
Geoffrey C. Hsu	Member	Member OrbiMed Advisors LLC
Evan D. Sotiriou	Chief Financial Officer	Chief Financial Officer OrbiMed Advisors LLC

 

Schedule II

 

The business and operations of OrbiMed Capital GP V LLC are managed by the executive officers and directors of its managing member, OrbiMed Advisors LLC, set forth on Schedule I.

 

EXHIBIT INDEX

Exhibit	Description
1.	Joint Filing Agreement among OrbiMed Advisors LLC and OrbiMed Capital GP V LLC.
2.	Amended and Restated Investors’ Rights Agreement by and among the Issuer and each of the persons listed on Schedule A thereto, dated as of August 21, 2017 (incorporated by reference to Exhibit 4.2 to the Issuer’s Registration Statement on Form S-1 (SEC 333-220337), filed with the SEC on September 5, 2017).

 

 

 

 

 

 

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EXHIBIT 1

JOINT FILING AGREEMENT

 

The undersigned hereby agree that the Statement on this Schedule 13D, dated June 4, 2018 (the “Schedule 13D”), with respect to the Shares of Rhythm Pharmaceuticals, Inc. is filed on behalf of each of us pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, and that this Agreement shall be included as an Exhibit to this Schedule 13D. Each of the undersigned agrees to be responsible for the timely filing of the Schedule 13D, and for the completeness and accuracy of the information concerning itself contained therein. This Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

 

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the 4^th day of June 2018.

 

	OrbiMed Capital GP V LLC
	By:	OrbiMed Advisors LLC its Managing Member
	By:	/s/ Jonathan T. Silverstein
		Name:	Jonathan T. Silverstein
		Title:	Member of OrbiMed Advisors LLC
	By:	/s/ Sven H. Borho
		Name:	Sven H. Borho
		Title:	Member of OrbiMed Advisors LLC
	By:	/s/ Carl L. Gordon
		Name:	Carl L. Gordon
		Title:	Member of OrbiMed Advisors LLC

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