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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:

        ""Net Sales" shall mean, the gross invoiced sales amount of the Cardene
PMB Product or any Ularitide product, as applicable, [****]*, and in each case
less the following items ("Net Sales Adjustments") as applicable to the Cardene
PMB Product or the Ularitide product, as applicable, to the extent such items
are reasonable and customary under industry practices and [****]* and are
consistent in application with [****]*:

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

        (a)   actual credits or allowances granted upon returns, rejections or
recalls (due to spoilage, damage, expiration of useful life or otherwise),
retroactive price reductions, or billing corrections during the accounting
period in which such sales are recorded;

        (b)   invoiced freight, postage, shipping and insurance, handling,
export fees or tariffs, customs expenses and other transportation costs actually
incurred by Buyer;

        (c)   credits or allowances actually granted including, without
limitation, quantity, cash and other trade discounts (collectively, "Credits"),
provided, however, Credits shall not include any credit, allowance or discount
given with respect to the sale of the [****]*;

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

        (d)   taxes (including, without limitation, sales, value-added or excise
taxes, but excluding income taxes imposed on the income of Buyer or its
Affiliates and withholding taxes imposed on amounts payable to Buyer or its
Affiliates), tariffs, customs duties, surcharges and other governmental charges
incurred in connection with the production, sale, transportation, delivery, use,
exportation or importation of CV Products that are incurred at time of sale or
are directly related to the sale;

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        (e)   discounts, refunds, rebates, charge backs, fees, credits or
allowances (including, without limitation, amounts incurred in connection with
government-mandated rebate and discount programs, third party rebates and charge
backs, hospital buying group/group purchasing organization administration fees
and managed care organization rebates) actually deducted from payment of
invoices by customers or paid to customers during the accounting period in which
such sales are recorded, offset by any such amounts that had been deducted from
invoices or paid to customers in error and have been paid back to Buyer; and

        (f)    distribution fees and sales commissions to third parties,
actually paid or incurred at the time of sale and which effectively reduce the
selling price,

all in accordance with standard allocation procedures, allowance methodologies
and accounting methods consistently applied. For the avoidance of doubt, the
transfer of any Cardene PMB Product by Buyer or its Affiliates to another
Affiliate of Buyer for purposes of sale to an independent third party shall not
be considered a sale; in such cases, Net Sales shall be determined based on the
gross invoiced sales by such Affiliate to an independent third party, less the
Net Sales Adjustments allowed under this Section."

        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:

        "(A) the following royalties on Net Sales of the Cardene PMB Product
commencing on July 1, 2009 through June 30, 2010 and each 12-month period
thereafter until December 31, 2017:

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 %

however, in the event of a Successful Launch of a Generic PMB, the royalty rates
set forth in this Section 3.3(b)(iii)(A) shall be reduced by fifty percent (50%)
(i.e., divided by two (2));"

        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:

"iv.    If Buyer or its Affiliates shall enter into an agreement to out-license
rights to sell the Cardene PMB Product outside the Territory, which agreement
would not be deemed a Distribution Agreement (as defined below) (an
"Outlicense"), or enter into a distributor, reseller or other similar agreement
(a "Distribution Agreement") for the sale of the Cardene PMB Product outside the
Territory, then Buyer shall pay Seller twenty percent (20%) of all consideration
and contingent payments, whether in cash or in kind, received by Buyer or its
Affiliates under such Outlicenses and Distribution Agreements, including, but
not limited to, upfront payments, milestones and royalties, to the extent Buyer
or its Affiliates earns such consideration or payments before December 31, 2017.
If Buyer or its Affiliates shall receive non-cash consideration or contingent
payments under any Outlicense or Distribution Agreement, the fair market value
of such non-cash consideration or payment on the date of

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such transfer as known to Buyer, or as reasonably estimated by Buyer if unknown,
shall be included in determining payments due to Seller hereunder."

        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 Corporation
 
 
By:
 
/s/ Andrew Guggenhime

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    Name:   Andrew Guggenhime     Title:   SVP & CFO
 
 
EKR Therapeutics, Inc.
 
 
By:
 
/s/ Howard Weisman

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    Name:   Howard Weisman     Title:   President and Chief Executive Officer

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Exhibit 10.25

CONFIDENTIAL PROVISIONS REDACTED
Amendment No. 2 to Asset Purchase Agreement