FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person * MPM BIOVENTURES III LLC   2. Issuer Name and Ticker or Trading Symbol Radius Health, Inc. [NONE] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director __X__ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O MPM ASSET MANAGEMENT, 200 CLARENDON ST., 54TH FLOOR 3. Date of Earliest Transaction (Month/Day/Year) 12/14/2011 (Street) BOSTON, MA 02116 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) ___ Form filed by One Reporting Person _X_ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Series A-1 Convertible Preferred Stock

(1)

12/14/2011

P

61,408 (2)

(1)

(1)

Common Stock

614,080 (1)

(1)

269,724

I

See footnote (3)

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
MPM BIOVENTURES III LLC C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X
MPM BIOVENTURES III PARALLEL FUND, L.P. C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X
MPM BIOVENTURES III GMBH & CO. Beteiligungs KG C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X
MPM BIOVENTURES III L.P. C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X
MPM BIOVENTURES III GP L.P. C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X
MPM BIOVENTURES III-QP L.P. C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X
MPM ASSET MANAGEMENT INVESTORS 2003 BVIII LLC C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X
HENNER DENNIS C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X
STEINMETZ MICHAEL C/O MPM ASSET MANAGEMENT 200 CLARENDON ST., 54TH FLOOR BOSTON, MA 02116		X

Signatures

/s/ Luke Evnin, Series A Member of MPM BioVentures III LLC		12/16/2011
**Signature of Reporting Person		Date
/s/ Luke Evnin, Series A Member of MPM BioVentures III LLC, the general partner of MPM BioVentures III GP, L.P., the general partner of MPM BioVentures III Parallel Fund, L.P.		12/16/2011
**Signature of Reporting Person		Date
/s/ Luke Evnin, Series A Member of MPM BioVentures III LLC, the general partner of MPM BioVentures III GP, L.P., in its capacity as the Managing Limited Partner of MPM BioVentures III GmbH & Co. Beteiligungs KG		12/16/2011
**Signature of Reporting Person		Date
/s/ Luke Evnin, Series A Member of MPM BioVentures III LLC, the general partner of MPM BioVentures III GP, L.P., the general partner of MPM BioVentures III, L.P.		12/16/2011
**Signature of Reporting Person		Date
/s/ Luke Evnin, Series A Member of MPM BioVentures III LLC, the general partner of MPM BioVentures III GP, L.P.		12/16/2011
**Signature of Reporting Person		Date
/s/ Luke Evnin, Series A Member of MPM BioVentures III LLC, the general partner of MPM BioVentures III GP, L.P., the general partner of MPM BioVentures III-QP, L.P.		12/16/2011
**Signature of Reporting Person		Date
/s/ Luke Evnin, member of MPM Asset Management Investors 2003 BVIII LLC		12/16/2011
**Signature of Reporting Person		Date
/s/ Dennis Henner		12/16/2011
**Signature of Reporting Person		Date
/s/ Michael Steinmetz		12/16/2011
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Each share of Series A-1 Convertible Preferred Stock (the "Preferred Stock") has no expiration date and is convertible at any time, in whole or in part, at the election of the holder at a conversion ratio of 10 shares of Common Stock for every 1 share of Preferred Stock.
(2)	The shares were purchased as follows: 51,119 by MPM BioVentures III-QP, L.P. ("BV III QP"), 3,437 by MPM BioVentures III, L.P. ("BV III"), 989 by MPM Asset Management Investors 2003 BVIII LLC ("AM 2003"), 1,543 by MPM BioVentures III Parallel Fund, L.P. ("BV Parallel") and 4,320 by MPM BioVentures III GmbH & Co. Beteiligungs KG ("BV KG"). MPM BioVentures III GP, L.P. ("MPM III GP") and MPM BioVentures III LLC ("MPM III LLC") are the direct and indirect general partners of BV III QP, BV III, BV Parallel and BV KG. Luke Evnin, Ansbert Gadicke, Nicholas Galakatos, Dennis Henner, Nicholas Simon III, Michael Steinmetz and Kurt Wheeler are the Series A members of MPM III LLC and the managers of AM 2003. Each reporting person disclaims beneficial ownership of the securities reported herein except to the extent of his or its respective pecuniary interest therein.
(3)	The shares are held as follows: 224,528 by BV III QP, 15,096 by BV III, 4,346 by AM 2003, 6,779 by BV Parallel and 18,975 by BV KG. Each reporting person disclaims beneficial ownership of the securities reported herein except to the extent of his or its respective pecuniary interest therein.
Remarks: See Form 4 for Nicholas Galakatos filed simultaneously herewith for additional members of this joint filing.

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