Exhibit 10.27

CERTAIN MATERIAL (INDICATED BY AN ASTERISK) HAS BEEN OMITTED FROM THIS DOCUMENT
PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT. THE OMITTED MATERIAL HAS BEEN
FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

AMENDMENT TO CO-PROMOTION AGREEMENT

THIS AMENDMENT TO CO-PROMOTION AGREEMENT (this “Amendment”) is entered into as
of the 20th day of December, 2011, by and between Astellas Pharma US, Inc.
(“Astellas”), and Zogenix, Inc. This Amendment amends that certain Co-Promotion
Agreement dated as of July 31, 2009 (the “Agreement”), between the Parties (as
defined in the Agreement).

WHEREAS, the Parties desire to amend the Agreement in certain respects,
including providing that the Initial Term shall end on March 31, 2012, all
pursuant to the terms and conditions hereof;

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged by the Parties, the Parties agree as follows:

1. Definitions; Conflict. Unless otherwise defined in this Amendment, the terms
and conditions used in this Amendment shall have the meanings ascribed thereto
in the Agreement. In the event of any conflict between the terms and conditions
of this Amendment and those set forth in the Agreement, those set forth in the
Agreement shall control.

2. Zogenix Promotion to Selected Professionals Within Astellas Segment During
2012 Bridge Period. Notwithstanding anything to the contrary in the Agreement,
for the period commencing upon January 1, 2012, and continuing until March 31,
2012 (the “2012 Bridge Period”), Zogenix shall have the right, subject to
applicable Legal Requirements, to Detail the Product to those Professionals in
the Astellas Segment within the Territory whose identities are set forth in an
exhibit prepared and exchanged by the Parties as of the date of this Amendment
(the “Selected Professionals”). The Parties acknowledge and agree that the lack
of Details of the Product to the Selected Professionals by Astellas during the
2012 Bridge Period shall not be a consideration in whether Astellas has used
commercially reasonable efforts to Detail the Product in the Astellas Segment
during the 2012 Bridge Period.

3. Service Fees During 2012 Bridge Period. With regard to each [***] during the
2012 Bridge Period, the definition of “Astellas Net Sales” in Section 1.16 of
the Agreement is modified by [***] the number of [***] as measured by the third
party national audit by Wolters Kluwer (or such other Third Party data source as
the Parties may agree from time to time), excluding [***].

4. Astellas Promotional Funding Commitment During 2012 Bridge Period; Provision
of Remaining Tool Kits. Notwithstanding anything to the contrary in the
Agreement, with regard to the 2012 Bridge Period, the Parties agree that the
Base Brand A&P Budget and the Commercial Plan shall not contemplate, provide or
require a level of spending by Astellas with respect to A&P Expenses, and
Astellas shall have no obligation [***] in aggregate with respect

 

*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

 

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to A&P Expenses incurred during the 2012 Bridge Period. With regard to the
quantity of [***] identified as [***] that are in Astellas’ possession at its
[***] on December 31, 2011, Astellas shall [***].

5. Promotion Transition Plan. The Parties shall use good faith efforts to agree
on a Promotion transition plan no later than February 1, 2012, setting forth a
defined process to introduce Zogenix Sales Representatives to mutually agreed
Professionals in the Astellas Segment.

6. JPRC Review of Promotional Material. Notwithstanding anything to the contrary
in the Agreement, from the date of this Amendment until termination of the
Agreement, (a) the JPRC shall not be responsible to review or approve any
Promotional Material that is solely for use by Zogenix, (b) Zogenix shall have
sole responsibility for the review and approval of such Promotional Materials,
and (c) Zogenix shall not use any Astellas Trademark in such Promotional
Materials.

7. Term and Termination of Agreement. Sub-Sections 8.2(a)(i) through (v),
8.2(a)(vi)(B), 8.2(a)(vi)(D), 8.2(b), 8.2(c)(ii), 8.2(c)(iii) and 8.4(a) through
(d) of the Agreement, and all references in the Agreement to such sub-Sections,
are amended by deleting such sub-Sections and references in their entirety,
including the terms and conditions set forth in the Agreement to the extent
applicable to each such deleted sub-Sections. Section 8.1 of the Agreement is
amended by deleting such Section in its entirety and substituting the following
in lieu thereof:

“Section 8.1 Term

The term of the Agreement shall commence on the Effective Date and shall
continue, unless terminated sooner in accordance with this Article VIII, until
March 31, 2012 (the “Initial Term” or the “Term”).”

8. Termination of Product Agreements. As of the date of the termination of the
Agreement, Astellas shall have terminated any and all agreements entered into by
Astellas with third parties to the extent relating to the purpose of the
Agreement (the “Product Agreements”). Zogenix shall have no responsibility for
any obligations under the Product Agreements from and after the termination of
the Agreement.

9. Tail Payments. Section 7.8 of the Agreement is amended by deleting such
Section in its entirety and substituting the following in lieu thereof:

“Section 7.8 Tail Payments

Following the Term, Zogenix shall pay Astellas the following payments based on
Astellas Net Sales during the last full twelve (12) months ending March 31, 2012
(such period, the “Final Astellas Promotional Period;” each such payment, a
“Tail Payment”):

 

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the Commission. Confidential treatment has been requested with respect to the
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(a) On July [***] 2013, an amount equal to [***] ([***]%) of the Astellas Net
Sales during the Final Astellas Promotional Period; and

(b) On July [***] 2014, an amount equal to [***] ([***]%) of the Astellas Net
Sales during the Final Astellas Promotional Period.

In the event the Tail Payment due under (a) above is not received by Astellas on
or before the date upon which it is due, the Tail Payment under (b) above shall
become immediately due and payable.”

10. Trademark Consent. The Parties acknowledge and agree that, upon termination
of the Agreement, the Trademark Consent dated as of May 10, 2010, between the
Parties shall also immediately and automatically terminate.

11. No Claim of Material Breach. Each Party acknowledges that the other Party
has not committed a material breach of the Agreement and, in partial
consideration of the execution of this Amendment by the other Party, each Party
hereby waives and releases, as of the date of this Amendment, any claim, demand
and cause of action, of every nature, that it has or may have against the other
Party for any material breach of the Agreement which heretofore has or may have
been committed by the other Party, including, without limitation, any claim for
breach of contract, declaratory relief, misrepresentation, or any other form of
damage or theory of recovery whatsoever arising out of, based upon or relating
to, whether foreseen or unforeseen and whether known or unknown. The foregoing
does not constitute a waiver or release of any material breach of the Agreement
that the other Party hereafter may commit, and does not waive, release or limit
any right or claim to indemnification that a Party may have under Article XI of
the Agreement or any right or claim that either Party has to receive payments as
set forth herein or pursuant to Article VII of the Agreement.

The Parties each acknowledge that they have been advised by legal counsel and
are familiar with the provisions of California Civil Code Section 1542, which
provides as follows:

“A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR
SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF EXECUTING THE RELEASE, WHICH IF
KNOWN BY HIM MUST HAVE MATERIALLY AFFECTED HIS SETTLEMENT WITH THE DEBTOR.”

Each of the Parties recognizes and understands that such section might apply to
and cover the aforementioned claims, demands and/or causes of action, and hereby
expressly waives any rights it may have under this section as well as under any
other statutes or common law principles of similar effect.

12. No Unapproved Offsets. Except for such offsets as are expressly permitted
under Sections 7.6 and 7.7 of the Agreement, neither Party shall reduce from or
offset against any amount due and payable by such Party under the Agreement any
payment or amount that is or

 

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the Commission. Confidential treatment has been requested with respect to the
omitted portions.

 

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may be due to such Party under the Agreement or otherwise, without the prior
written approval of the other Party; in the absence of such approval, all such
payments shall be made when and as due under the Agreement.

13. Survival. The rights and obligations of the Parties arising by virtue of
this Amendment shall survive the termination of the Agreement in accordance with
the provisions of Sections 8.4 and 12.4 of the Agreement, including without
limitation provisions of the Agreement regarding accounting, reconciliation,
reporting and auditing.

14. Publicity. In regard to the termination of the Agreement on March 31, 2012,
neither Party shall issues any publicity, news release, or other public comment
or announcement (including, without limitation, any statements to health care
practitioners or customers) without the prior written consent of the other
Party, except that no such consent shall be required to the extent such
publicity, release, comment or announcement is, in the opinion of legal counsel
to the Party making such disclosure, required by law or the rules or
requirements of any stock exchange. Either Party making any such disclosure
required by law or the rules or requirements of any stock exchange shall (unless
prohibited by law or the rules or requirements of any stock exchange) give the
other Party an opportunity to review and comment upon the form and content of
such disclosure before it is made. Once any such publicity or other statement
has been approved by the other Party for disclosure, either Party may make
subsequent public disclosures of the content thereof (to the extent the
disclosure of such content remains accurate and not misleading) without the
further written approval of the other Party.

15. Further Assurances. Each Party shall undertake such reasonable further acts
and execute and deliver such further documents as may be necessary or as the
other Party may reasonably require to implement or give effect hereto.

16. Counterparts. This Amendment may be signed in any number of counterparts,
each of which shall be deemed to be an original and all of which, when taken
together, shall have the same effect as if the signatures thereon were on the
same instrument.

17. Full Force and Effect. Except as amended hereby, all of the terms and
conditions of the Agreement shall remain in full force and effect.

IN WITNESS WHEREOF, the parties have executed this Amendment as of the date
first above written.

 

ASTELLAS PHARMA US, INC.     ZOGENIX, INC. By:  

/s/ M. Yoshida

    By:  

/s/ Roger L. Hawley

  Title: President & CEO       Title: CEO   Date: December 20, 2011       Date:
Dec. 20, 2011

 

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December 20, 2011

MEMORANDUM OF EXHIBIT

Reference is made to that certain Co-Promotion Agreement by and between Astellas
Pharma US, Inc. (“Astellas”) and Zogenix, Inc. (“Zogenix”) dated as of July 31,
2009, as amended by execution of an Amendment (the “Amendment”) on the date
hereof (as so amended, the “Co-Promotion Agreement”). Capitalized terms used but
not otherwise defined herein have the meaning set forth in the Co-Promotion
Agreement.

Astellas and Zogenix hereby acknowledge and agree as follows:

 

  •  

A list of the Selected Professionals (as referenced in Section 2 of the
Amendment to Co-Promotion Agreement) is attached hereto as Exhibit A.

This Memorandum of Exhibit may be signed in any number of counterparts, each of
which shall be deemed to be an original and all of which, when taken together,
shall have the same effect as if the signatures thereon were on the same
instrument.

 

  Zogenix, Inc.       Astellas Pharma US, Inc.  

/s/ Roger L. Hawley

     

/s/ M. Yoshida

  By: Roger L. Hawley       By: M. Yoshida   Its: CEO       Its: President & CEO

 

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EXHIBIT A

[List of Selected Professionals attached]

 

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[***]

Eighty Four (84) Pages omitted

 

*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

 

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