Exhibit 10.42

FIRST AMENDMENT TO
DEVELOPMENT AND COMMERCIALIZATION AGREEMENT

     This Amendment to Development and Commercialization Agreement (this
“Amendment”) is made and entered into this Fourteenth day of December, 2004 (the
“Effective Date”), by and between Advancis Pharmaceutical Corporation, a
Delaware corporation (“Advancis”), and Par Pharmaceutical, Inc., a Delaware
corporation (“Par”).

     WHEREAS, Advancis and Par are parties to that certain Development and
Commercialization Agreement dated May 28, 2004 (the “Development and
Commercialization Agreement”); and

     WHEREAS, Advancis and Par wish to modify the Development and
Commercialization Agreement so that the development and commercialization of an
amoxicillin-only product for the pediatric population targeting acute otitis
media will be replaced by the development and commercialization of an
amoxicillin clavulanic acid product for such indication, in accordance with the
terms of this Amendment.

     NOW, THEREFORE, in consideration of the mutual covenants and promises
contained in this Amendment and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, Advancis and Par agree
as follows:

     1. Definitions; Format. All capitalized terms not otherwise defined in this
Amendment shall have the definitions ascribed to such terms in the Development
and Commercialization Agreement. Where a textual passage is amended in part
only, new language will be shown double underlined, deleted language will be
shown in strikeout, and language that is unmodified will be shown as an ellipsis
(“...”). Double underlining, deleted language and ellipses are for convenience
only and are not part of the Development and Commercialization Agreement, as
amended.

     2. Development Plan. Pursuant to Section 4.1 of the Development and
Commercialization Agreement, the Development Plan had been agreed to by the
Parties by letter dated June 2, 2004. The Parties agree to work together in good
faith to mutually agree in writing upon an amended and restated Development Plan
within one week of the Effective Date of this Amendment which will reflect the
modifications to the Development Program set forth in this Amendment (the
“Amended and Restated Development Plan”). The Amended and Restated Development
Plan will be substantially similar to the most recent development plan materials
circulated by Advancis to Par as of the date of this Amendment.

     3. Modification of Definition of Compound. Section 1.20, the definition of
“Compound” is amended to read as follows:

“Compound” means, individually and collectively, as applicable, the Amox-Only
Compound and the Amox-Clav Compound.  the compound amoxicillin, including all
racemates, chelates, complexes, enantiomers, diastereoisomers, salts, bases,
esters, hydrates, solvates, polymorphs, crystal forms, crystal habits,

-1-

 

--------------------------------------------------------------------------------

 

prodrugs, isotopic or radiolabeled equivalents, metabolites, or the like,
thereof and all mixtures of any of the foregoing.

     4. Addition of New Definition of Amox-Only Compound. A new Section 1.20.1,
the definition of “Amox-Only Compound” is inserted to read as follows:

“Amox-Only Compound” means the compound amoxicillin, including all racemates,
chelates, complexes, enantiomers, diastereoisomers, salts, bases, esters,
hydrates, solvates, polymorphs, crystal forms, crystal habits, prodrugs,
isotopic or radiolabeled equivalents, metabolites, or the like, thereof and all
mixtures of any of the foregoing.

     5. Addition of New Definition of Amox-Clav Compound. A new Section 1.20.2,
the definition of “Amox-Clav Compound” is inserted to read as follows:

“Amox-Clav Compound” means the compounds amoxicillin and clavulanic acid,
including all racemates, chelates, complexes, enantiomers, diastereoisomers,
salts, bases, esters, hydrates, solvates, polymorphs, crystal forms, crystal
habits, prodrugs, isotopic or radiolabeled equivalents, metabolites, or the
like, thereof and all mixtures of any of the foregoing.

     6. Modification of Definition of Adult Product. Section 1.1, the definition
of “Adult Product” is amended to read as follows:

“Adult Product” means a pharmaceutical presentation of the Amox-Only Compound
(a) that utilizes or incorporates PULSYSÔ, and (b) that contains no active
pharmaceutical ingredient (including any active pharmaceutical ingredient that
acts as an [***]) other than the Amox-Only Compound, and (c) that is used or is
being developed for the Adult Product Indication., and (c) that is used or is
being developed for the Adult Product Indication, other than formulations of
Exhibit A.

     7. Modification of Definition of Pediatric Product. Section 1.59, the
definition of “Pediatric Product” is amended to read as follows:

“Pediatric Product” means, as the case may be, (a) a pharmaceutical presentation
of the Amox-Only Compound (a)(i) that utilizes or incorporates PULSYSÔ, (b)(ii)
that contains no active pharmaceutical ingredient (including any active
pharmaceutical ingredient that acts as a [***]) other than the Amox-Only
Compound, and (c) (iii) that is used or is being developed for the Pediatric
Product Indications, [***]; and/or (b) the pharmaceutical presentation of the
Amox-Clav Compound (i) that utilizes or incorporates PULSYSÔ,

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 UNDER THE SECURITIES
AND EXCHANGE ACT OF 1934, AS AMENDED.

-2-

 

--------------------------------------------------------------------------------

 

that contains no active pharmaceutical ingredient other than the Amox-Clav
Compound, and (iii) that is used or is being developed for the Pediatric Product
Indication [***] other than formulations of Exhibit A.

     8. Modification of Definition of Adult Product Indication. Section 1.2, the
definition of “Adult Product Indication” is amended to read as follows:

“Adult Product Indication” means [***] in adolescents/adults in accordance with
the protocols set forth in the Amended and Restated Development Plan, [***] and
any other indication agreed to by the Parties.

     9. Modification of Definition of Pediatric Product Indications.
Section 1.60, the definition of “Pediatric Product Indications” is amended to
read as follows:

“Pediatric Product Indications” means (i)  [***]; (ii)  [***] , both in
accordance with the protocols set forth in the Amended and Restated Development
Plan,; and (c) any other indications agreed to by the Parties.

     10. Deletion of Exhibit A. Exhibit A is deleted from the Development and
Commercialization Agreement. In addition, the last sentence of Section 14.2 (No
Conflicts), which refers to Exhibit A, is deleted.

     11. Modification of Section 2.3 Non-Competition. Section 2.3,
“Non-Competition” is amended to read as follows:

Non-Competition. During the Term, and except as through the Collaboration
pursuant to this Agreement neither pParty for the Territory shall develop,
market, sell or distribute any pharmaceutical product that [***], wherein (a)
the sole active pharmaceutical ingredient in such product is the Amox-Only
Compound; or (b) with respect to indications for acute otitis media in the
pediatric population, the only active pharmaceutical ingredients in such product
are the Amox-Clav Compound. Notwithstanding the foregoing, it is expressly
agreed that this Section 2.3 does not apply to any formulations of Exhibit A.

     12. Section 4.2.2.2. The Parties hereby understand and agree that
Section 4.2.2.2 of the Development and Commercialization Agreement shall apply
with the following clarifications: (a) [***], and (b) [***].

     13. No Other Changes; Execution. Except as explicitly set forth in this
Amendment, no amendment or modification to the Development and Commercialization
Agreement is hereby made. This Amendment may be executed in counterparts and
delivered by facsimile.

[***] INDICATES MATERIAL THAT HAS BEEN OMITTED AND FOR WHICH CONFIDENTIAL
TREATMENT HAS BEEN REQUESTED. ALL SUCH OMITTED MATERIAL HAS BEEN FILED WITH THE
SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 UNDER THE SECURITIES
AND EXCHANGE ACT OF 1934, AS AMENDED.

-3-

 

--------------------------------------------------------------------------------

 

     IN WITNESS WHEREOF, the Parties hereto have caused this Amendment to be
executed as a sealed instrument in their names by their properly and duly
authorized officers or representatives as of the date first above written.

ADVANCIS PHARMACEUTICAL CORPORATION

By: /s/ Edward M. Rudnic                    

Print Name: Edward M. Rudnic            

Title: Chairman, President and CEO    

 

PAR PHARMACEUTICAL, INC.

By: /s/ Scott Tarriff                                 

Print Name: Scott Tarriff                         

Title: President and CEO                         

-4-