<SEC-DOCUMENT>0001193125-19-075029.txt : 20190314
<SEC-HEADER>0001193125-19-075029.hdr.sgml : 20190314
<ACCEPTANCE-DATETIME>20190314172905
ACCESSION NUMBER:		0001193125-19-075029
CONFORMED SUBMISSION TYPE:	S-8
PUBLIC DOCUMENT COUNT:		3
FILED AS OF DATE:		20190314
DATE AS OF CHANGE:		20190314
EFFECTIVENESS DATE:		20190314

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ZAFGEN, INC.
		CENTRAL INDEX KEY:			0001374690
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				203857670
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-8
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-230291
		FILM NUMBER:		19682047

	BUSINESS ADDRESS:	
		STREET 1:		175 PORTLAND STREET
		STREET 2:		4TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02114
		BUSINESS PHONE:		617-622-4003

	MAIL ADDRESS:	
		STREET 1:		175 PORTLAND STREET
		STREET 2:		4TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02114

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ZAFGEN INC
		DATE OF NAME CHANGE:	20060906
</SEC-HEADER>
<DOCUMENT>
<TYPE>S-8
<SEQUENCE>1
<FILENAME>d715846ds8.htm
<DESCRIPTION>S-8
<TEXT>
<HTML><HEAD>
<TITLE>S-8</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>As filed with the Securities and Exchange Commission on March&nbsp;14, 2019 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration
<FONT STYLE="white-space:nowrap">No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT> </B></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:14pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:14pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>WASHINGTON, D.C. 20549 </B></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM
<FONT STYLE="white-space:nowrap">S-8</FONT> </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><I>UNDER </I></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><I>THE
SECURITIES ACT OF 1933 </I></B></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:22pt; font-family:Times New Roman" ALIGN="center"><B>ZAFGEN, INC. </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Exact Name
of Registrant as Specified in its Charter) </B></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:8pt" ALIGN="center">


<TR>
<TD WIDTH="50%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="48%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" ALIGN="center"><B>Delaware</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"><B><FONT STYLE="white-space:nowrap">20-3857670</FONT></B></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(State or Other Jurisdiction of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Incorporation or Organization)</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(I.R.S. Employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Identification No.)</B></P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Zafgen, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>175 Portland Street, 4th Floor </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boston, Massachusetts 02114 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(617) <FONT STYLE="white-space:nowrap">622-4003</FONT> </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Address of Principal Executive Offices) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Zafgen, Inc. 2014 Stock Option and Incentive Plan </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Full Title of the Plans) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Jeffrey Hatfield </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Chief
Executive Officer </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Zafgen, Inc. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>175 Portland Street, 4th Floor </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boston, Massachusetts 02114 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name and Address of Agent For Service) </B></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><I>Copy to: </I></B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Mitchell S. Bloom, Esq. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Danielle Lauzon, Esq. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Goodwin Procter LLP </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>100
Northern Avenue </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Boston, Massachusetts 02210 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(617) <FONT STYLE="white-space:nowrap">570-1000</FONT> </B></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Indicate by check mark whether the registrant is a
large accelerated filer, an accelerated filer, a <FONT STYLE="white-space:nowrap">non-accelerated</FONT> filer, a smaller reporting company, or an emerging growth company. See the definitions of &#147;large accelerated filer,&#148; &#147;accelerated
filer,&#148; &#147;smaller reporting company,&#148; and &#147;emerging growth company&#148; in Rule <FONT STYLE="white-space:nowrap">12b-2</FONT> of the Exchange Act. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>
<TD WIDTH="33%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="2%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="30%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="30%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="1%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Large&nbsp;accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">&#9744;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">&#9746;</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"><FONT STYLE="white-space:nowrap">Non-accelerated</FONT> filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">&#9744;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Smaller&nbsp;reporting&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">&#9746;</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Emerging growth Company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top">&#9746;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period
for complying with any new or revised financial accounting standards provided pursuant to Section&nbsp;7(a)(2)(B) of the Securities Act.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&#9746; </P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:0pt;margin-bottom:0pt;page-break-before:always"></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>CALCULATION OF REGISTRATION FEE </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:8pt" ALIGN="center">


<TR>
<TD WIDTH="42%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="15%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="13%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="13%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="13%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Title of Securities</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>to be Registered</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Amount</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>to be</B></P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Registered
(1)</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Proposed</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Maximum</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Offering
Price</B></P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>per Share</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Proposed</B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Maximum</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Aggregate</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Offering Price</B></P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000; BORDER-BOTTOM:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Amount of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Registration&nbsp;Fee</B></P></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Common Stock, $0.001 par value per share</P></TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">1,491,488&nbsp;shares&nbsp;(2)</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">$2.89&nbsp;(3)</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">$4,310,400.32</TD>
<TD VALIGN="bottom" STYLE=" BORDER-LEFT:1px solid #000000; BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-BOTTOM:1px solid #000000">$522.42</TD></TR>
</TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Pursuant to Rule 416 under the Securities Act of 1933, as amended (the &#147;Securities Act&#148;), this
registration statement on <FONT STYLE="white-space:nowrap">Form&nbsp;S-8</FONT> (this &#147;Registration Statement&#148;) shall also cover any additional shares of common stock, par value $0.001 per share (the &#147;Common Stock&#148;), of Zafgen,
Inc. (the &#147;Registrant&#148;), which become issuable under the Registrant&#146;s 2014 Stock Option and Incentive Plan (the &#147;Plan&#148;) by reason of any stock dividend, stock split, recapitalization or any other similar transaction effected
without the receipt of consideration which results in an increase in the number of the Registrant&#146;s outstanding shares of Common Stock. </P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Represents an automatic increase to the number of shares available for issuance under the Plan, effective
January&nbsp;1, 2019. Shares available for issuance under the Plan were previously registered on registration statements on Form <FONT STYLE="white-space:nowrap">S-8</FONT> filed with the Securities and Exchange Commission on June&nbsp;19, 2014
(Registration <FONT STYLE="white-space:nowrap">No.&nbsp;333-196900),</FONT> June&nbsp;12, 2015 (Registration <FONT STYLE="white-space:nowrap">No.&nbsp;333-204931),</FONT> March&nbsp;15, 2016 (Registration
<FONT STYLE="white-space:nowrap">No.&nbsp;333-210216),</FONT> March&nbsp;10, 2017 (Registration <FONT STYLE="white-space:nowrap">No.&nbsp;333-216602),</FONT> and March&nbsp;9, 2018 (Registration
<FONT STYLE="white-space:nowrap">No.&nbsp;333-223561).</FONT> </P></TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">(3)</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(h) of the Securities
Act, and based on the average of the high and low sale prices of the Registrant&#146;s Common Stock, as quoted on the Nasdaq Global Select Market, on March&nbsp;13, 2019. </P></TD></TR></TABLE>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>
</DIV></Center>


<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>EXPLANATORY NOTE </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">This Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> registers additional shares of Common Stock under the Registrant&#146;s 2014
Stock Option and Incentive Plan (the &#147;Plan&#148;). The number of shares of Common Stock reserved and available for issuance under the Plan is subject to an automatic annual increase on each January&nbsp;1, beginning in 2015, by an amount equal
to four percent of the number of shares of Common Stock issued and outstanding on the immediately preceding December&nbsp;31 or such lesser number of shares of Common Stock as determined by the Compensation Committee of the Registrant&#146;s Board
of Directors. Accordingly, on January&nbsp;1, 2019, the number of shares of Common Stock reserved and available for issuance under the plan increased by 1,491,488. This Registration Statement registers these additional 1,491,488 shares of Common
Stock. The additional shares are of the same class as other securities relating to the Plan for which the Registrant&#146;s registration statement filed on Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Registration
<FONT STYLE="white-space:nowrap">Nos.&nbsp;333-196900,</FONT> <FONT STYLE="white-space:nowrap">333-204931,</FONT> <FONT STYLE="white-space:nowrap">333-210216,</FONT> <FONT STYLE="white-space:nowrap">333-216602,</FONT> and <FONT
STYLE="white-space:nowrap">333-223561)</FONT> on June&nbsp;19, 2014, June&nbsp;12, 2015, March&nbsp;15, 2016, March&nbsp;10, 2017 and March&nbsp;9, 2018 are effective. The information contained in the Registrant&#146;s registration statements on
Form <FONT STYLE="white-space:nowrap">S-8</FONT> (Registration <FONT STYLE="white-space:nowrap">Nos.&nbsp;333-196900,</FONT> <FONT STYLE="white-space:nowrap">333-204931,</FONT> <FONT STYLE="white-space:nowrap">333-210216,</FONT> <FONT
STYLE="white-space:nowrap">333-216602,</FONT> and <FONT STYLE="white-space:nowrap">333-223561)</FONT> is hereby incorporated by reference pursuant to General Instruction E. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">2 </P>

</DIV></Center>


<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Part II </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>Item&nbsp;8. Exhibits. </B></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">See the Exhibit Index on the page
immediately preceding the exhibits for a list of exhibits filed as part of this registration statement, which Exhibit Index is incorporated herein by reference. </P>
<P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>EXHIBIT INDEX </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Exhibit<BR>No.</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Description</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1374690/000119312514222253/d642727dex41.htm">Form of Common Stock certificate of the registrant (Incorporated by reference to Exhibit 4.1 to the registrant&#146;s Registration Statement on
 Form <FONT STYLE="white-space:nowrap">S-1,</FONT> as amended (File <FONT STYLE="white-space:nowrap">No.&nbsp;333-195391)).</FONT></A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1374690/000119312514227208/d642727dex32.htm">Form of Amended and Restated Certificate of Incorporation (Incorporated by reference to Exhibit 3.2 to the registrant&#146;s Registration Statement
 on Form <FONT STYLE="white-space:nowrap">S-1,</FONT> as amended (File <FONT STYLE="white-space:nowrap">No.&nbsp;333-195391)).</FONT></A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1374690/000119312514222253/d642727dex34.htm">Form of Amended and Restated <FONT STYLE="white-space:nowrap">By-laws</FONT> (Incorporated by reference to Exhibit 3.4 to the registrant&#146;s
 Registration Statement on Form <FONT STYLE="white-space:nowrap">S-1,</FONT> as amended (File <FONT STYLE="white-space:nowrap">No.&nbsp;333-195391)).</FONT> </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>4.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1374690/000119312514149201/d642727dex42.htm">Third Amended and Restated Investors&#146; Rights Agreement by and among the registrant and certain of its stockholders, dated as of November&nbsp;25,
 2013 (Incorporated by reference to Exhibit 4.2 to the registrant&#146;s Registration Statement on Form <FONT STYLE="white-space:nowrap">S-1,</FONT> as amended (File <FONT STYLE="white-space:nowrap">No.&nbsp;333-195391)).</FONT> </A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>5.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d715846dex51.htm">Opinion of Goodwin Procter LLP.</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d715846dex231.htm">Consent of PricewaterhouseCoopers LLP, independent registered public accounting firm.</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="d715846dex51.htm">Consent of Goodwin Procter LLP (included in Exhibit 5.1).</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1*</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="#sig">Power of attorney (included on signature page).</A></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"><A HREF="http://www.sec.gov/Archives/edgar/data/1374690/000119312514227208/d642727dex102.htm">2014 Stock Option and Incentive Plan and forms of agreements thereunder (Incorporated by reference to Exhibit 10.2 to the registrant&#146;s Registration
 Statement on Form <FONT STYLE="white-space:nowrap">S-1</FONT> (File <FONT STYLE="white-space:nowrap">No.&nbsp;333-195391)).</FONT></A></TD></TR>
</TABLE> <P STYLE="line-height:8.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000;width:10%">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">*</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left">Filed herewith. </P></TD></TR></TABLE> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">3 </P>

</DIV></Center>


<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURES </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe that it meets all of
the requirements for filing on Form <FONT STYLE="white-space:nowrap">S-8</FONT> and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Boston, Commonwealth of
Massachusetts, on the 14th day of March, 2019. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>
<TD WIDTH="6%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="92%"></TD></TR>


<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" COLSPAN="3"><B>ZAFGEN, INC.</B></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">By:</TD>
<TD VALIGN="bottom" STYLE=" BORDER-BOTTOM:1px solid #000000">&nbsp;</TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000">/s/ Jeffrey Hatfield</TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Jeffrey Hatfield</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Chief Executive
Officer</P></TD></TR>
</TABLE></DIV> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><A NAME="sig"></A>POWER OF ATTORNEY AND SIGNATURES </B></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">KNOW ALL BY THESE PRESENT, that each individual whose signature appears below hereby constitutes and appoints each of Jeffrey Hatfield and Patricia L. Allen as
such person&#146;s true and lawful <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorney-in-fact</FONT></FONT> and agent with full power of substitution and resubstitution, for such person in such person&#146;s name, place and
stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8,</FONT> and to file the same, with all exhibits thereto, and all
documents in connection therewith, with the Securities and Exchange Commission granting unto each said <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorney-in-fact</FONT></FONT> and agent full power and authority to do and
perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as such person might or could do in person, hereby ratifying and confirming all that any said <FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">attorney-in-fact</FONT></FONT> and agent, or any substitute or substitutes of any of them, may lawfully do or cause to be done by virtue hereof. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement has been signed by the following person in the capacities
and on the date indicated. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>
<TD WIDTH="37%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="44%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="15%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Name</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Title</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Date</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Jeffrey Hatfield</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Jeffrey Hatfield</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Chief Executive Officer and Director</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><I>(Principal Executive Officer)</I></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">March&nbsp;14, 2019</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Patricia L. Allen</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Patricia L. Allen</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Chief Financial Officer</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman"><I>(Principal Financial
and Accounting Officer)</I></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">March&nbsp;14, 2019</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Peter Barrett</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Peter Barrett, Ph.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Chairman of the Board of Directors</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">March&nbsp;14, 2019</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Thomas O. Daniel</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Thomas O. Daniel, M.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">March&nbsp;14, 2019</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Wendy Everett</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Wendy Everett Sc.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">March&nbsp;14, 2019</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Robert J. Perez</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Robert J. Perez</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">March&nbsp;14, 2019</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ John L. LaMattina</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">John L. LaMattina, Ph.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">March&nbsp;14, 2019</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Cameron Geoffrey McDonough</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cameron Geoffrey McDonough, M.D.</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">March&nbsp;14, 2019</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Frank E. Thomas</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Frank E. Thomas</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Director</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" NOWRAP ALIGN="center">March&nbsp;14, 2019</TD></TR>
</TABLE> <P STYLE="font-size:18pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">4 </P>

</DIV></Center>

</BODY></HTML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>2
<FILENAME>d715846dex51.htm
<DESCRIPTION>EX-5.1
<TEXT>
<HTML><HEAD>
<TITLE>EX-5.1</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 5.1 </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:54%; text-indent:-2%; font-size:10pt; font-family:Times New Roman">March&nbsp;14, 2019 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Zafgen,
Inc. </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">175 Portland Street, 4th Floor </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Boston, MA 02114 </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left">Re:</TD>
<TD ALIGN="left" VALIGN="top"> <P STYLE=" margin-top:0pt ; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman; " ALIGN="left"><U>Securities Being Registered under Registration Statement on Form
<FONT STYLE="white-space:nowrap">S-8</FONT></U> </P></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Ladies and Gentlemen: </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We have acted as counsel to you in connection with your filing of a Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT>
(the &#147;Registration Statement&#148;) pursuant to the Securities Act of 1933, as amended (the &#147;Securities Act&#148;), on or about the date hereof relating to an aggregate of 1,491,488 shares (the &#147;Shares&#148;) of Common Stock, $0.001
par value per share, of Zafgen, Inc., a Delaware corporation (the &#147;Company&#148;), that may be issued pursuant to the Company&#146;s 2014 Stock Option and Incentive Plan (the &#147;Plan&#148;). </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We have reviewed such documents and made such examination of law as we have deemed appropriate to give the opinions set forth below. We have
relied, without independent verification, on certificates of public officials and, as to matters of fact material to the opinion set forth below, on certificates of officers of the Company. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The opinion set forth below is limited to the Delaware General Corporation Law. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">For purposes of the opinion set forth below, we have assumed that a sufficient number of authorized but unissued shares of the Company&#146;s
Common Stock will be available for issuance when the Shares are issued. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Based on the foregoing, we are of the opinion that the Shares
have been duly authorized and, upon issuance and delivery against payment therefor in accordance with the terms of the Plan, will be validly issued, fully paid and nonassessable. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">We hereby consent to the inclusion of this opinion as Exhibit 5.1 to the Registration Statement. In giving our consent, we do not admit that
we are in the category of persons whose consent is required under Section&nbsp;7 of the Securities Act or the rules and regulations thereunder. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:54%; text-indent:-2%; font-size:10pt; font-family:Times New Roman">Very truly yours, </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:54%; text-indent:-2%; font-size:10pt; font-family:Times New Roman">/<SMALL>S</SMALL>/ G<SMALL>OODWIN</SMALL> P<SMALL>ROCTER</SMALL> LLP </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; margin-left:54%; text-indent:-2%; font-size:10pt; font-family:Times New Roman">GOODWIN PROCTER LLP </P> <P STYLE="font-size:18pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P>
</DIV></Center>

</BODY></HTML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>3
<FILENAME>d715846dex231.htm
<DESCRIPTION>EX-23.1
<TEXT>
<HTML><HEAD>
<TITLE>EX-23.1</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">


<Center><DIV STYLE="width:8.5in" align="left">
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Exhibit 23.1 </B></P>
<P STYLE="margin-top:24pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">We hereby consent to the incorporation by reference in this Registration Statement on Form <FONT STYLE="white-space:nowrap">S-8</FONT> of our report dated
March&nbsp;14, 2019 relating to the financial statements, which appears in Zafgen, Inc.&#146;s Annual Report on Form <FONT STYLE="white-space:nowrap">10-K</FONT> for the year ended December&nbsp;31, 2018. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">/s/ PricewaterhouseCoopers LLP </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Boston, Massachusetts </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">March&nbsp;14, 2019 </P>
</DIV></Center>

</BODY></HTML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
