October 14, 2015 - 3: Initial statement of beneficial ownership of securities

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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3235-0104

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(Print or Type Responses)

1. Name and Address of Reporting Person ^*

MPM BIOVENTURES V, L.P.

2. Date of Event Requiring Statement (Month/Day/Year)
10/14/2015

3. Issuer Name and Ticker or Trading Symbol
Cerecor Inc. [CERC]

(Last)

(First)

(Middle)

C/O MPM ASSET MANAGEMENT, 450 KENDALL STREET

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

_____ Director	__X__ 10% Owner
_____ Officer (give title below)	_____ Other (specify below)

5. If Amendment, Date Original Filed(Month/Day/Year)

(Street)

CAMBRIDGE, MA 02142

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 Beneficially Owned

1.Title of Security
(Instr. 4)

2. Amount of Securities Beneficially Owned
(Instr. 4)

3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)

4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
	Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series B Convertible Preferred Stock	⁽¹⁾	⁽¹⁾	Common Stock	595,436 ⁽²⁾	$ ⁽¹⁾	I	See Footnote ⁽³⁾

Reporting Owners

Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
MPM BIOVENTURES V, L.P. C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X
MPM ASSET MANAGEMENT INVESTORS BV5 LLC C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X
MPM BIOVENTURES V GP LLC C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X
MPM BIOVENTURES V LLC C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X
GADICKE ANSBERT C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X
EVNIN LUKE C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X
KAILIAN VAUGHN M C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X
Scopa James Paul C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X
Foley Todd C/O MPM ASSET MANAGEMENT 450 KENDALL STREET CAMBRIDGE, MA 02142		X

Signatures

By Ansbert Gadicke, member of MPM BioVentures V LLC, the managing member of MPM BioVentures V GP LLC /s/ Ansbert Gadicke		10/14/2015
^**Signature of Reporting Person		Date
By Ansbert Gadicke, member of MPM BioVentures V LLC, the managing member of MPM BioVentures V GP LLC, the general partner of MPM BioVentures V, L.P. /s/ Ansbert Gadicke		10/14/2015
^**Signature of Reporting Person		Date
By Ansbert Gadicke, member of MPM BioVentures V LLC, the manager of MPM Asset Management Investors BV5 LLC /s/ Ansbert Gadicke		10/14/2015
^**Signature of Reporting Person		Date
/s/ Luke Evnin		10/14/2015
^**Signature of Reporting Person		Date
/s/ Todd Foley		10/14/2015
^**Signature of Reporting Person		Date
/s/ Ansbert Gadicke		10/14/2015
^**Signature of Reporting Person		Date
/s/ Vaughn M. Kailian		10/14/2015
^**Signature of Reporting Person		Date
/s/ James Paul Scopa		10/14/2015
^**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(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)	The shares of Series B Convertible Preferred Stock (the "Series B Shares") will convert automatically into Common Stock, on a 1-for-0.03571 basis, immediately prior to the closing of the Issuer's initial public offering, and have no expiration date.
(2)	Reflects the conversion of the Series B Shares into shares of Common Stock.
(3)	The shares are held as follows: 573,170 by MPM BioVentures V, L.P. ("BV V") and 22,266 by MPM Asset Management Investors BV5 LLC ("AM BV5"). MPM BioVentures V GP LLC ("BV GP") is the general partner of BV V. MPM BioVentures V LLC ("BV LLC") is the managing member of BV GP and AM BV5. Ansbert Gadicke, Luke Evnin, Vaughn M. Kailian, James Paul Scopa and Todd Foley are the members of BV LLC. Each Reporting Person disclaims beneficial ownership of the securities except to the extent of his or its respective pecuniary interest therein.

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