Exhibit 10.25

CONFIDENTIAL PROVISIONS REDACTED

Amendment No. 2  to  Asset Purchase Agreement

This Amendment No. 2 to Asset Purchase Agreement (this "Amendment"), effective
as of October 19, 2009 (the "Amendment Effective Date"), is made by and between Facet Biotech Corporation, a Delaware corporation
("Facet"), and EKR Therapeutics, Inc., a Delaware corporation ("EKR"). Unless otherwise defined
in this Amendment, capitalized terms used in this Amendment shall have the meanings assigned thereto in the Asset Purchase Agreement, effective February 4, 2008, between Facet (as successor in
interest to PDL BioPharma, Inc. thereunder) and EKR, as amended March 7, 2008 (as amended, the "Agreement").

WHEREAS, Facet and EKR desire to amend the Agreement in accordance with Section 14.7 of the Agreement;

NOW, THEREFORE, in consideration of the mutual covenants and agreements set forth in this Amendment, Facet and EKR agree as follows:

1.     Within
two (2) business days after the Amendment Effective Date, EKR shall pay to Facet a one-time, non-refundable,
non-creditable amendment fee of Two Million United States Dollars ($2,000,000), which payment EKR shall make by wire transfer in immediately available funds to such account as Facet has
notified EKR.

2.     The
definition of "Net Sales" in Section 1.60 of the Agreement is deleted in its entirety and replaced with the following definition:







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3.     Section 3.1(b)(ii)
of the Agreement is deleted in its entirety.

4.     Subpart (A)
of Section 3.1(b)(iii) is amended and replaced in its entirety with the following:



Net Sales Per 12-month Period
(July 1 through the following June 30)

Royalty Rate$0 - $40,000,000


12
%$40,000,001 - $80,000,000


14
%>$80,000,001


17
%




5.     EKR
and Facet acknowledge that the amendment of Section 3.1(b)(iii)(A) set forth in Section 4 of this Amendment is retroactively effective and applies to
all Net Sales of the Cardene PMB Product on or after July 1, 2009. Within two (2) business days after the Amendment Effective Date, EKR shall pay to Facet the royalties that would have
been due to Facet under Section 3.1(b)(iii)(A) through the Amendment Effective Date, less the amount of royalties EKR has paid to Facet with respect to Net Sales of the Cardene PMB Product
occurring on or after July 1, 2009. EKR and Facet further acknowledge that all royalties on Net Sales of Cardene PMB Product reported by EKR to Facet for the quarter ending June 30, 2009
have been paid and that no amounts are due and owing with respect to the amount of such Net Sales EKR reported to Facet.

6.     The
Agreement is amended by adding new Section 3.1(b)(iv), which provides:



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7.     EKR
acknowledges that it assumed at the Closing, and hereby expressly assumes, all of the obligations of PDL BioPharma, Inc. (which obligations were originally
obligations of Centocor, Inc.) (the "Obligations") under the Amended and Restated Agreement dated November 23, 1998 (the
"DuPont Agreement"), between Centocor, Inc. and DuPont Pharmaceuticals Company ("DuPont"). EKR
shall perform all of the Obligations arising on or after the Closing Date and thereafter, including the royalty payment obligations to Royalty Pharma Finance Trust (the assignee of DuPont with respect
to certain rights under the DuPont Agreement), and shall promptly pay to Royalty Pharma Finance Trust or its designee or assignee all amounts due and owing under the DuPont Agreement within five
(5) business days after the Amendment Effective Date. For the avoidance of doubt, the DuPont Agreement is hereby added to the list of Assumed Contracts set forth in Attachment 2.1(p).

8.     Except
as amended herein, all other terms and conditions of the Agreement shall remain in full force and effect.

9.     This
Amendment may be executed in counterparts, each of which shall be deemed an original and all of which together shall constitute one and the same instrument. Any
signature page delivered by facsimile or electronic image transmission shall be binding to the same extent as an original signature page.

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IN WITNESS WHEREOF, the parties hereby accept and agree to the terms and conditions of this Amendment as of the date set forth above.

Facet Biotech CorporationBy:

/s/ Andrew GuggenhimeName:

Andrew GuggenhimeTitle:

SVP & CFOEKR Therapeutics, Inc.By:

/s/ Howard WeismanName:

Howard WeismanTitle:

President and Chief Executive Officer


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