CUSIP No.
|
98885E103
|
13G
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Page 2 of 11 Pages
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1.
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NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Deerfield Mgmt, L.P.
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||
2.
|
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
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(a) o
(b) ý
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3.
|
SEC USE ONLY
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||
4.
|
CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
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||
NUMBER OF SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
|
5.
|
SOLE VOTING POWER
0
|
|
6.
|
SHARED VOTING POWER
1,301,018 (1)
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||
7.
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SOLE DISPOSITIVE POWER
0
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||
8.
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SHARED DISPOSITIVE POWER
1,301,018 (1)
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||
9.
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,301,018 (1)
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||
10.
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
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o
|
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11.
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PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
4.78%
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||
12.
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TYPE OF REPORTING PERSON*
PN
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CUSIP No.
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98885E103
|
13G
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Page 3 of 11 Pages
|
1.
|
NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Deerfield Management Company, L.P.
|
||
2.
|
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
|
(a) o
(b) ý
|
|
3.
|
SEC USE ONLY
|
||
4.
|
CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
|
||
NUMBER OF SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
|
5.
|
SOLE VOTING POWER
0
|
|
6.
|
SHARED VOTING POWER
1,301,018 (2)
|
||
7.
|
SOLE DISPOSITIVE POWER
0
|
||
8.
|
SHARED DISPOSITIVE POWER
1,301,018 (2)
|
||
9.
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,301,018 (2)
|
||
10.
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
|
o
|
|
11.
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
4.78%
|
||
12.
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TYPE OF REPORTING PERSON*
PN
|
CUSIP No.
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98885E103
|
13G
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Page 4 of 11 Pages
|
1.
|
NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Deerfield Partners, L.P.
|
||
2.
|
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
|
(a) o
(b) ý
|
|
3.
|
SEC USE ONLY
|
||
4.
|
CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
|
||
NUMBER OF SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
|
5.
|
SOLE VOTING POWER
0
|
|
6.
|
SHARED VOTING POWER
525,888
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||
7.
|
SOLE DISPOSITIVE POWER
0
|
||
8.
|
SHARED DISPOSITIVE POWER
525,888
|
||
9.
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
525,888
|
||
10.
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
|
o
|
|
11.
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PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
1.93%
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||
12.
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TYPE OF REPORTING PERSON*
PN
|
CUSIP No.
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98885E103
|
13G
|
Page 5 of 11 Pages
|
1.
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NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Deerfield International Master Fund, L.P.
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2.
|
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
|
(a) o
(b) ý
|
|
3.
|
SEC USE ONLY
|
||
4.
|
CITIZENSHIP OR PLACE OF ORGANIZATION
British Virgin Islands
|
||
NUMBER OF SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
|
5.
|
SOLE VOTING POWER
0
|
|
6.
|
SHARED VOTING POWER
669,312
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||
7.
|
SOLE DISPOSITIVE POWER
0
|
||
8.
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SHARED DISPOSITIVE POWER
669,312
|
||
9.
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
669,312
|
||
10.
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
|
o
|
|
11.
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PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.46%
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||
12.
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TYPE OF REPORTING PERSON*
PN
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CUSIP No.
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98885E103
|
13G
|
Page 6 of 11 Pages
|
1.
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NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
Deerfield Special Situations Fund, L.P.
|
||
2.
|
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
|
(a) o
(b) ý
|
|
3.
|
SEC USE ONLY
|
||
4.
|
CITIZENSHIP OR PLACE OF ORGANIZATION
Delaware
|
||
NUMBER OF SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
|
5.
|
SOLE VOTING POWER
0
|
|
6.
|
SHARED VOTING POWER
105,818
|
||
7.
|
SOLE DISPOSITIVE POWER
0
|
||
8.
|
SHARED DISPOSITIVE POWER
105,818
|
||
9.
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
105,818
|
||
10.
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
|
o
|
|
11.
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
0.39%
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||
12.
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TYPE OF REPORTING PERSON*
PN
|
CUSIP No.
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98885E103
|
13G
|
Page 7 of 11 Pages
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1.
|
NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
James E. Flynn
|
||
2.
|
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
|
(a) o
(b) ý
|
|
3.
|
SEC USE ONLY
|
||
4.
|
CITIZENSHIP OR PLACE OF ORGANIZATION
United States
|
||
NUMBER OF SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON WITH
|
5.
|
SOLE VOTING POWER
0
|
|
6.
|
SHARED VOTING POWER
1,301,018 (3)
|
||
7.
|
SOLE DISPOSITIVE POWER
0
|
||
8.
|
SHARED DISPOSITIVE POWER
1,301,018 (3)
|
||
9.
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,301,018 (3)
|
||
10.
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
|
o
|
|
11.
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
4.78%
|
||
12.
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TYPE OF REPORTING PERSON*
IN
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CUSIP No.
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98885E103
|
13G
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Page 8 of 11 Pages
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Item 1(a). | Name of Issuer: | |
Zafgen, Inc.
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Item 1(b). | Address of Issuer's Principal Executive Offices: | |
175 Portland Street
Boston, MA 02114
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Item 2(a). | Name of Person Filing: | |
James E. Flynn, Deerfield Mgmt, L.P., Deerfield Management Company, L.P., Deerfield Partners, L.P., Deerfield International Master Fund, L.P., Deerfield Special Situations Fund, L.P.
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Item 2(b). | Address of Principal Business Office, or if None, Residence: | |
780 Third Avenue, 37th Floor, New York, NY 10017
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Item 2(c). | Citizenship: | |
Deerfield Mgmt, L.P., Deerfield Management Company, L.P., Deerfield Partners, L.P., Deerfield Special Situations Fund, L.P. - Delaware limited partnerships;
Deerfield International Master Fund, L.P. – British Virgin Islands limited partnership;
James E. Flynn - United States citizen
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Item 2(d). | Title of Class of Securities: | |
Common Stock
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Item 2(e). | CUSIP Number: | |
98885E103
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Item 3. |
If This Statement is Filed Pursuant to Rule 13d-1(b), or 13d-2(b) or (c), Check Whether the Person Filing is a:
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(a) | o | Broker or dealer registered under Section 15 of the Exchange Act. | |
(b) | o | Bank as defined in Section 3(a)(6) of the Exchange Act. | |
(c) | o | Insurance company as defined in Section 3(a)(19) of the Exchange Act. | |
(d) | o | Investment company registered under Section 8 of the Investment Company Act. |
(e) | o | An investment adviser in accordance with Rule 13d-1(b)(1)(ii)(E); |
(f) | o | An employee benefit plan or endowment fund in accordance with Rule 13d-1(b)(1)(ii)(F); |
(g) | o | A parent holding company or control person in accordance with Rule 13d-1(b)(1)(ii)(G); |
(h) | o | A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act; |
(i) | o | A church plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act; |
CUSIP No.
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98885E103
|
13G
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Page 9 of 11 Pages
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(j) | o |
A non-U.S. institution in accordance with Rule 13d-1(b)(1)(ii)(J);
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k) | o |
Group, in accordance with Rule 13d-1(b)(1)(ii)(K).
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Item 4. | Ownership. |
(a) |
Amount beneficially owned**:
|
||
Deerfield Mgmt, L.P. – 1,301,018 shares
Deerfield Management Company, L.P. – 1,301,018 shares
Deerfield Partners, L.P. – 525,888 shares
Deerfield International Master Fund, L.P. - 669,312 shares
Deerfield Special Situations Fund, L.P. – 105,818 shares
James E. Flynn – 1,301,018 shares
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(b) |
Percent of class**:
|
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Deerfield Mgmt, L.P. – 4.78%
Deerfield Management Company, L.P. – 4.78%
Deerfield Partners, L.P. – 1.93%
Deerfield International Master Fund, L.P. - 2.46%
Deerfield Special Situations Fund, L.P. – 0.39%
James E. Flynn – 4.78%
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(c) |
Number of shares as to which such person has**:
|
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(i) |
Sole power to vote or to direct the vote:
|
All Reporting Persons - 0
|
|||
(ii) |
Shared power to vote or to direct the vote:
|
Deerfield Mgmt, L.P. – 1,301,018
Deerfield Management Company, L.P. – 1,301,018
Deerfield Partners, L.P. – 525,888
Deerfield International Master Fund, L.P. – 669,312
Deerfield Special Situations Fund,L.P. – 105,818
James E. Flynn - 1,301,018
|
(iii) |
Sole power to dispose or to direct the disposition of:
|
All Reporting Persons - 0
|
|||
(iv) |
Shared power to dispose or to direct the disposition of:
|
Deerfield Mgmt, L.P. – 1,301,018
Deerfield Management Company, L.P. – 1,301,018
Deerfield Partners, L.P. – 525,888
Deerfield International Master Fund, L.P. – 669,312
Deerfield Special Situations Fund,L.P. – 105,818
James E. Flynn - 1,301,018
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CUSIP No.
|
98885E103
|
13G
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Page 10 of 11 Pages
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Item 5.
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Ownership of Five Percent or Less of a Class.
|
|
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Item 6.
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Ownership of More Than Five Percent on Behalf of Another Person. |
|
N/A
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Item 7.
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Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person. |
|
N/A
|
Item 8.
|
Identification and Classification of Members of the Group. |
|
See Exhibit B
|
Item 9.
|
Notice of Dissolution of Group. |
|
N/A
|
Item 10.
|
Certifications. |
CUSIP No.
|
98885E103
|
13G
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Page 11 of 11 Pages
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