PENWEST PHARMACEUTICALS CO Executive Retention Agreement

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                                                                   Exhibit 10.28

                           PENWEST PHARMACEUTICALS CO.

                          Executive Retention Agreement


     THIS EXECUTIVE RETENTION AGREEMENT by and between Penwest Pharmaceuticals
Co., a Washington corporation (the "Company"), and [__________] (the
"Executive") is made as of December [__], 2005 (the "Effective Date").

     WHEREAS, the Company recognizes that, as is the case with many
publicly-held corporations, the possibility of a change in control of the
Company exists and that such possibility, and the uncertainty and questions
which it may raise among key personnel, may result in the departure or
distraction of key personnel to the detriment of the Company and its
stockholders, and

     WHEREAS, the Company desires to reinforce and encourage the continued
employment and dedication of the Company's key personnel without distraction
from the possibility of a change in control of the Company and related events
and circumstances.

     NOW, THEREFORE, as an inducement for and in consideration of the Executive
remaining in its employ, the Company agrees that the Executive shall receive the
severance benefits set forth in this Agreement in the event the Executive's
employment with the Company is terminated under the circumstances described
below in connection with or subsequent to a Change in Control (as defined
below).

     1. Key Definitions.

     As used herein, the following terms shall have the following respective
meanings:

        1.1 "Change in Control" means an event or occurrence set forth in any
one or more of subsections (a) through (d) below (including an event or
occurrence that constitutes a Change in Control under one of such subsections
but is specifically exempted from another such subsection):

             (a) the acquisition by an individual, entity or group (within the
meaning of Section 13(d)(3) or 14(d)(2) of the 1934 Securities Exchange Act, as
amended) (a "Person") of beneficial ownership of any capital stock of the
Company if, after such acquisition, such Person beneficially owns (within the
meaning of Rule 13d-3 promulgated under the 1934 Securities Exchange Act, as
amended) 50% or more of the combined voting power of the then-outstanding
securities of the Company entitled to vote generally in the election of
directors (the "Outstanding Company Voting Securities"); provided, however, that
for purposes of this subsection (a), the following acquisitions shall not
constitute a Change in Control Event: (i) any acquisition directly from the
Company, (ii) any acquisition by any employee benefit plan (or related trust)
sponsored or maintained by the Company or any corporation controlled by the
Company or (iii) any acquisition by any corporation pursuant to a Business
Combination (as defined below) which complies with clauses (i) and (ii) of
subsection (c) of this definition; or

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             (b) such time as the Continuing Directors (as defined below) do not
constitute a majority of the Board of Directors of the Company (or, if
applicable, the Board of Directors of a successor corporation to the Company),
where the term "Continuing Director" means at any date a member of the Board (i)
who was a member of the Board on the date of execution of this Agreement or (ii)
who was nominated or elected subsequent to such date by at least a majority of
the directors who were Continuing Directors at the time of such nomination or
election or whose election to the Board was recommended or endorsed by at least
a majority of the directors who were Continuing Directors at the time of such
nomination or election; provided, however, that there shall be excluded from
this clause (ii) any individual whose initial assumption of office occurred as a
result of an actual or threatened election contest with respect to the election
or removal of directors or other actual or threatened solicitation of proxies or
consents, by or on behalf of a person other than the Board; or

             (c) the consummation of a merger, consolidation, reorganization,
recapitalization or share exchange involving the Company or a sale or other
disposition of all or substantially all of the assets of the Company (a
"Business Combination"), unless, immediately following such Business
Combination, each of the following two conditions is satisfied: (i) all or
substantially all of the individuals and entities who were the beneficial owners
of the Outstanding Company Voting Securities immediately prior to such Business
Combination beneficially own, directly or indirectly, more than 60% the combined
voting power of the then-outstanding securities entitled to vote generally in
the election of directors, of the resulting or acquiring corporation in such
Business Combination (which shall include, without limitation, a corporation
which as a result of such transaction owns the Company or substantially all of
the Company's assets either directly or through one or more subsidiaries) (such
resulting or acquiring corporation is referred to herein as the "Acquiring
Corporation") in substantially the same proportions as their ownership of the
Outstanding Company Voting Securities immediately prior to such Business
Combination and (ii) no Person (excluding any employee benefit plan (or related
trust) maintained or sponsored by the Company or by the Acquiring Corporation)
beneficially owns, directly or indirectly, 50% of the combined voting power of
the then-outstanding securities of the Acquiring Corporation entitled to vote
generally in the election of directors (except to the extent that such ownership
existed prior to the Business Combination); or

             (d) the liquidation or dissolution of the Company.

        1.2 "Change in Control Date" means the first date during the Term (as
defined in Section 2) on which a Change in Control occurs.

        1.3 "Cause" means willful misconduct by the Executive or willful failure
by the Executive to perform his/her responsibilities to the Company (including,
without limitation, breach by the Executive of any provision of any employment,
consulting, advisory, nondisclosure, non-competition or other similar agreement
between the Executive and the Company), as determined by the Company, which
determination shall be conclusive.

        1.4 "Good Reason" means the occurrence, without the Executive's written
consent, of any of the following events or circumstances:


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             (a) the assignment to the Executive of duties inconsistent in any
material respect with the Executive's position (including status, offices,
titles and reporting requirements), authority or responsibilities in effect
immediately prior to the earliest to occur of (i) the Change in Control Date,
(ii) the date of the execution by the Company of the initial written agreement
or instrument providing for the Change in Control or (iii) the date of the
adoption by the Board of a resolution providing for the Change in Control (with
the earliest to occur of such dates referred to herein as the "Measurement
Date"), or any other action or omission by the Company which results in a
material diminution in such position, authority or responsibilities; or

             (b) a change by the Company in the location at which the Executive
performs his/her principal duties for the Company to a new location that is
outside a radius of 35 miles from the City of Danbury, Connecticut.

Notwithstanding the occurrence of any event or circumstance set forth in clauses
(a) or (b) above, such occurrence shall not be deemed to constitute Good Reason
if, prior to the Date of Termination specified in the Notice of Termination
(each as defined in Section 3.2(a)) given by the Executive in respect thereof,
such event or circumstance has been fully corrected and the Executive has been
reasonably compensated for any losses or damages resulting therefrom (provided
that such right of correction by the Company shall only apply to the first
Notice of Termination for Good Reason given by the Executive).

        1.5 "Disability" means a condition causing the Executive to be disabled
within the meaning of Section 22(e)(3) of the Internal Revenue Code of 1986, as
amended, and any regulations promulgated thereunder.

     2. Term of Agreement. This Agreement, and all rights and obligations of the
parties hereunder, shall take effect upon the Effective Date and shall expire
upon the first to occur of (a) the expiration of the Term (as defined below) if
a Change in Control has not occurred during the Term, (b) the termination of the
Executive's employment with the Company prior to the Change in Control Date, (c)
the date 12 months after the Change in Control Date, if the Executive is still
employed by the Company as of such later date, or (d) the fulfillment by the
Company of all of its obligations under this Agreement if the Executive's
employment with the Company terminates within 12 months following the Change in
Control Date. "Term" shall mean the period commencing as of the Effective Date
and continuing in effect through December 31, 2008.

     3. Employment Status; Termination Following Change in Control.

        3.1 Not an Employment Contract. The Executive acknowledges that this
Agreement does not constitute a contract of employment or impose on the Company
any obligation to retain the Executive as an employee and that this Agreement
does not prevent the Executive from terminating employment at any time. If the
Executive's employment with the Company terminates for any reason and
subsequently a Change in Control shall occur, the Executive shall not be
entitled to any benefits hereunder.

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        3.2 Notice of Termination of Employment.

             (a) If the Change in Control Date occurs during the Term, any
termination of the Executive's employment by the Company or by the Executive
within 12 months following the Change in Control Date shall be communicated by a
written notice to the other party hereto (the "Notice of Termination"), given in
accordance with Section 7. Any Notice of Termination shall specify the effective
date of the employment termination (the "Date of Termination").

             (b) If the Executive seeks to terminate his/her employment with the
Company for Good Reason, then the Notice of Termination shall set forth in
reasonable detail the facts and circumstances claimed to provide a basis for
termination of the Executive's employment. The Date of Termination set forth in
such Notice of Termination shall not be less than 30 days or more than 60 days
after the date of delivery of such Notice of Termination. Any Notice of
Termination for Good Reason given by the