<PAGE>

                                                           Registration No. 333-


                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                            AASTROM BIOSCIENCES, INC.
             (Exact name of registrant as specified in its charter)

             Michigan                                    94-3096597
----------------------------------          ------------------------------------
   (State or other jurisdiction             (I.R.S. employer identification no.)
 of incorporation or organization)

                           24 Frank Lloyd Wright Drive
                            Ann Arbor, Michigan 48106
               ---------------------------------------------------
               (Address of principal executive offices) (Zip code)

     AMENDED AND RESTATED 1992 INCENTIVE AND NON-QUALIFIED STOCK OPTION PLAN
     -----------------------------------------------------------------------
                            (Full title of the plan)


                                  Todd Simpson
                             Chief Financial Officer
                            Aastrom Biosciences, Inc.
                           24 Frank Lloyd Wright Drive
                            Ann Arbor, Michigan 48106
                    ---------------------------------------
                    (Name and address of agent for service)

Telephone number, including area code, of agent for service: 734/930-5555

This registration statement shall become effective in accordance with Rule 462
promulgated under the Securities Act of 1933, as amended.

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------------------------
                                         CALCULATION OF REGISTRATION FEE
--------------------------------------------------------------------------------------------------------------------
<S>                            <C>                    <C>                   <C>                    <C>
                                                      Proposed maximum      Proposed maximum
Title of securities            Amount                 offering price per    aggregate offering     Amount of
to be registered               to be registered       share(1)              price                  registration fee

Common Stock, no par value     1,400,000              $    3.2656           $   4,571,840.00       $     1,206.96
TOTAL                          1,400,000              $    3.2656           $   4,571,840.00       $     1,206.96
                               =========
</TABLE>

-----------------------------
(1)     Estimated pursuant to Rule 457 solely for purposes of calculating the
        registration fee. The price is based upon the average of the high and
        low prices of the common stock on June 7, 2000, as reported on the
        Nasdaq National Market.
<PAGE>

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


Item 3. Incorporation of Documents by Reference

        Aastrom Biosciences, Inc. (the "Company") hereby incorporates by
reference in this registration statement the following documents:

        (a)  The Company's latest Annual Report filed on Form 10-K filed on
September 20, 1999 for fiscal year ended June 30, 1999, as amended on Form 8-K
filed December 10, 1999.

        (b)  The Company's Definitive Proxy Statement filed on October 6, 1999.

        (c)  The Company's Current Report on Form 8-K filed on October 27, 1999.

        (d)  The Company's Quarterly Report on Form 10-Q for the quarter ended
September 30, 1999 filed on November 12, 1999.

        (e)  The Company's Current Report on Form 8-K filed on December 10,
1999.

        (f)  The Company's Current Report on Form 8-K filed on January 19, 2000.

        (g)  The Company's Quarterly Report on Form 10-Q for the quarter ended
December 31, 1999 filed on February 14, 2000.

        (h)  The Company's Current Report on Form 8-K filed on March 3, 2000.

        (i)  The Company's Definitive Proxy Statement filed on April 4, 2000.
<PAGE>

        (j)  The Company's Quarterly Report on Form 10-Q for the quarter ended
March 31, 2000 filed on May 12, 2000.

        (k)  The final prospectus filed pursuant to Rule 424(b) containing
audited financial statements for the Company's fiscal year ended November 26,
1997.

        (l)  All other reports filed pursuant to Section 13(a) or 15(d) of the
Securities Exchange Act of 1934, as amended ("Exchange Act"), since the end of
the fiscal year covered by the document referred to in (a) above.

        (m)  The description of the Company's Common Stock contained in the
Company's Registration Statement on Form 8-A, filed pursuant to Section 12 of
the Exchange Act, including any amendment or report filed for the purpose of
updating such description.

        All documents subsequently filed by the Company pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-
effective amendment to this registration statement which indicates that all
securities offered hereby have been sold or which deregisters all securities
remaining unsold, shall be deemed to be incorporated by reference in this
registration statement and to be a part hereof from the date of filing of such
documents.


Item 4. Description of Securities

        The class of securities to be offered is registered under Section 12 of
the Exchange Act.


Item 5. Interests of Named Experts and Counsel

        The validity of the shares of Common Stock to be offered hereunder has
been passed upon for the Company by Pepper Hamilton LLP ("PH"), Detroit,
Michigan. As of June 8, 2000, Michael B. Staebler, a partner at PH, is the
beneficial owner of 1,333 shares of Common Stock.

Item 6. Indemnification of Directors and Officers

        Sections 1561 through 1565 of the Michigan Business Corporation Act (the
"MBCA") authorize a corporation to grant or a court to award, indemnity to
directors, officers, employees and agents in terms sufficiently broad to permit
such indemnification under certain circumstances for liabilities (including
reimbursement for expenses incurred) arising under the Securities Act of 1933.
<PAGE>

        The Bylaws of the Company provide that the Company shall, to the fullest
extent authorized or permitted by the MBCA, or other applicable law, indemnify a
director or officer who was or is a party or is threatened to be made a party to
any proceeding by or in the right of the Company to procure a judgment in its
favor by reason of the fact that such person is or was a director, officer,
employee or agent of the Company, against expenses, including actual and
reasonable attorneys' fees, and amounts paid in settlement incurred in
connection with the action or suit, if the indemnitee acted in good faith and in
a manner the person reasonably believed to be in, or not opposed to, the best
interests of the Company or its shareholders. This section also authorizes the
Company to advance expenses incurred by any agent of the Company in defending
any proceeding prior to the final disposition of such proceeding upon receipt of
an undertaking by or on behalf of the agent to repay such amount unless it shall
be determined ultimately that the agent is entitled to be indemnified.

        The Bylaws also authorize the Company to purchase and maintain insurance
on behalf of any person who is or was a director, officer, employee or agent of
the Company against any liability asserted against or incurred by such person in
such capacity or arising out of such person's status as such, regardless of
whether the Company would have the power to indemnify such person against such
liability under the provisions of the MBCA.

        The Company has entered into an indemnification agreement with certain
of its directors, officers and other key personnel, which contains provisions
that may in some respects be broader than the specific indemnification
provisions contained under applicable law. The indemnification agreement may
require the Company, among other things, to indemnify such directors, officers
and key personnel against certain liabilities that may arise by reason of their
status or service as directors, officers or employees of the Company, to advance
the expenses incurred by such parties as a result of any threatened claims or
proceedings brought against them as to which they could be indemnified, and to
the maximum extent that insurance coverage of such directors, officers and key
employees under the Company's directors' and officers' liability insurance
policies is maintained.

        Section 1209 of the MBCA permits a Michigan corporation to include in
its Articles of Incorporation a provision eliminating or limiting a director's
liability to a corporation or its shareholders for monetary damages for breaches
of fiduciary duty. The enabling statute provides, however, that liability for
breaches of the duty of loyalty, acts or omissions not in good faith or
involving intentional misconduct or knowing violations of the law, or the
receipt of improper personal benefits cannot be eliminated or limited in this
manner. The Company's Restated Articles of Incorporation include a provision
which eliminates, to the fullest extent permitted by the MBCA, director
liability for monetary damages for breaches of fiduciary duty.

Item 7. Exemption From Registration Claimed

        Inapplicable.

Item 8. Exhibits

        See Exhibit Index.
<PAGE>

Item 9. Undertakings

        (a)  Rule 415 Offering

        The undersigned registrant hereby undertakes:

             (1)  To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

                  (i)   To include any prospectus required by Section 10(a)(3)
of the Securities Act;

                  (ii)  To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent post-
effective amendment thereof) which, individually or in the aggregate, represent
a fundamental change in the information set forth in the registration statement;

                  (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement; provided,
however, that paragraphs (a)(1)(i) and (a)(l)(ii) do not apply if the
registration statement is on Form S-3 or Form S-8, and the information required
to be included in a post-effective amendment by those paragraphs is contained in
periodic reports filed by the registrant pursuant to Section 13 or Section 15(d)
of the Exchange Act that are incorporated by reference in the registration
statement.

             (2)  That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

             (3)  To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

        (b)  Filing incorporating subsequent Exchange Act documents by reference

        The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Exchange Act) that is
incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

        (h)  Request for acceleration of effective date or filing of
registration statement on Form S-8
<PAGE>

        Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
registrant pursuant to the foregoing provisions, or otherwise, the registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the registrant of expenses
incurred or paid by a director, officer or controlling person of the registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.
<PAGE>

                                    SIGNATURE

     Pursuant to the requirements of the Securities Act, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Ann Arbor, State of Michigan, on June 8, 2000.


                                        AASTROM BIOSCIENCES, INC.



                                        By: /s/ R. Douglas Armstrong
                                           -------------------------------------
                                           R. Douglas Armstrong, Ph.D.
                                           President and Chief Executive Officer
<PAGE>

                                POWER OF ATTORNEY

     The officers and directors of Aastrom Biosciences, Inc. whose signatures
appear below, hereby constitute and appoint R. Douglas Armstrong, and Todd E.
Simpson, and each of them, their true and lawful attorneys and agents, with full
power of substitution, each with power to act alone, to sign and execute on
behalf of the undersigned any amendment or amendments to this registration
statement on Form S-8, and each of the undersigned does hereby ratify and
confirm all that each of said attorney and agent, or their or his substitutes,
shall do or cause to be done by virtue hereof.

     Pursuant to the requirements of the Securities Act this registration
statement has been signed by the following persons in the capacities indicated
on June 8, 2000.

<TABLE>
<CAPTION>

Signature                                                   Title
----------------------------------------------------------- --------------------------------------------------------
<S>                                                         <C>
/s/ R. Douglas Armstrong                                    President, Chief Executive Officer and Director
-------------------------------------------------------     (Principal Executive Officer)
R. Douglas Armstrong, Ph.D.


/s/ Todd E. Simpson                                         Vice President, Finance and Administration and Chief
-------------------------------------------------------     Financial Officer (Principal Financial and Accounting
Todd E. Simpson                                             Officer)


/s/ Mary L. Campbell                                        Director
-------------------------------------------------------
Mary L. Campbell


/s/ Stephen E. Emerson                                      Director
-------------------------------------------------------
Stephen E. Emerson, M.D., Ph.D.

/s/ Arthur F. Staubitz                                      Director
-------------------------------------------------------
Arthur F. Staubitz

/s/ Joseph A. Taylor                                        Director
-------------------------------------------------------
Joseph A. Taylor
</TABLE>
<PAGE>

                                  EXHIBIT INDEX





 5       Opinion re legality

23.1     Consent of Counsel (included in Exhibit 5)

23.2     Consent of Independent Accountants

24       Power of Attorney (included in the signature pages to this registration
         statement)
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{"company-data": {"conformed-name": "AASTROM BIOSCIENCES INC", "cik": "0000887359", "assigned-sic": "2834", "irs-number": "943096597", "state-of-incorporation": "MI", "fiscal-year-end": "0630"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-38886", "film-number": "651748"}, "business-address": {"street1": "24 FRANKL LLOYD WRIGHT DR", "street2": "PO BOX 376", "city": "ANN ARBOR", "state": "MI", "zip": "48106", "phone": "7349305555"}}
Registration No. 333-

                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933

                            AASTROM BIOSCIENCES, INC.
             (Exact name of registrant as specified in its charter)

             Michigan                                    94-3096597
----------------------------------          ------------------------------------
   (State or other jurisdiction             (I.R.S. employer identification no.)
 of incorporation or organization)

                           24 Frank Lloyd Wright Drive
                            Ann Arbor, Michigan 48106
               ---------------------------------------------------
               (Address of principal executive offices) (Zip code)

     AMENDED AND RESTATED 1992 INCENTIVE AND NON-QUALIFIED STOCK OPTION PLAN
     -----------------------------------------------------------------------
                            (Full title of the plan)

                                  Todd Simpson
                             Chief Financial Officer
                            Aastrom Biosciences, Inc.
                           24 Frank Lloyd Wright Drive
                            Ann Arbor, Michigan 48106
                    ---------------------------------------
                    (Name and address of agent for service)

Telephone number, including area code, of agent for service: 734/930-5555

This registration statement shall become effective in accordance with Rule 462
promulgated under the Securities Act of 1933, as amended.
--------------------------------------------------------------------------------------------------------------------
                                         CALCULATION OF REGISTRATION FEE
--------------------------------------------------------------------------------------------------------------------
Proposed maximum      Proposed maximum
Title of securities            Amount                 offering price per    aggregate offering     Amount of
to be registered               to be registered       share(1)              price                  registration fee

Common Stock, no par value     1,400,000              $    3.2656           $   4,571,840.00       $     1,206.96
TOTAL                          1,400,000              $    3.2656           $   4,571,840.00       $     1,206.96
                               =========
-----------------------------
(1)     Estimated pursuant to Rule 457 solely for purposes of calculating the
        registration fee. The price is based upon the average of the high and
        low prices of the common stock on June 7, 2000, as reported on the
        Nasdaq National Market.
PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3. Incorporation of Documents by Reference

        Aastrom Biosciences, Inc. (the "Company") hereby incorporates by
reference in this registration statement the following documents:

        (a)  The Company's latest Annual Report filed on Form 10-K filed on
September 20, 1999 for fiscal year ended June 30, 1999, as amended on Form 8-K
filed December 10, 1999.

        (b)  The Company's Definitive Proxy Statement filed on October 6, 1999.

        (c)  The Company's Current Report on Form 8-K filed on October 27, 1999.

        (d)  The Company's Quarterly Report on Form 10-Q for the quarter ended
September 30, 1999 filed on November 12, 1999.

        (e)  The Company's Current Report on Form 8-K filed on December 10,
1999.

        (f)  The Company's Current Report on Form 8-K filed on January 19, 2000.

        (g)  The Company's Quarterly Report on Form 10-Q for the quarter ended
December 31, 1999 filed on February 14, 2000.

        (h)  The Company's Current Report on Form 8-K filed on March 3, 2000.

        (i)  The Company's Definitive Proxy Statement filed on April 4, 2000.
(j)  The Company's Quarterly Report on Form 10-Q for the quarter ended
March 31, 2000 filed on May 12, 2000.

        (k)  The final prospectus filed pursuant to Rule 424(b) containing
audited financial statements for the Company's fiscal year ended November 26,
1997.

        (l)  All other reports filed pursuant to Section 13(a) or 15(d) of the
Securities Exchange Act of 1934, as amended ("Exchange Act"), since the end of
the fiscal year covered by the document referred to in (a) above.

        (m)  The description of the Company's Common Stock contained in the
Company's Registration Statement on Form 8-A, filed pursuant to Section 12 of
the Exchange Act, including any amendment or report filed for the purpose of
updating such description.

        All documents subsequently filed by the Company pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act, prior to the filing of a post-
effective amendment to this registration statement which indicates that all
securities offered hereby have been sold or which deregisters all securities
remaining unsold, shall be deemed to be incorporated by reference in this
registration statement and to be a part hereof from the date of filing of such
documents.

Item 4. Description of Securities

        The class of securities to be offered is registered under Section 12 of
the Exchange Act.

Item 5. Interests of Named Experts and Counsel

        The validity of the shares of Common Stock to be offered hereunder has
been passed upon for the Company by Pepper Hamilton LLP ("PH"), Detroit,
Michigan. As of June 8, 2000, Michael B. Staebler, a partner at PH, is the
beneficial owner of 1,333 shares of Common Stock.

Item 6. Indemnification of Directors and Officers

        Sections 1561 through 1565 of the Michigan Business Corporation Act (the
"MBCA") authorize a corporation to grant or a court to award, indemnity to
directors, officers, employees and agents in terms sufficiently broad to permit
such indemnification under certain circumstances for liabilities (including
reimbursement for expenses incurred) arising under the Securities Act of 1933.
The Bylaws of the Company provide that the Company shall, to the fullest
extent authorized or permitted by the MBCA, or other applicable law, indemnify a
director or officer who was or is a party or is threatened to be made a party to
any proceeding by or in the right of the Company to procure a judgment in its
favor by reason of the fact that such person is or was a director, officer,
employee or agent of the Company, against expenses, including actual and
reasonable attorneys' fees, and amounts paid in settlement incurred in
connection with the action or suit, if the indemnitee acted in good faith and in
a manner the person reasonably believed to be in, or not opposed to, the best
interests of the Company or its shareholders. This section also authorizes the
Company to advance expenses incurred by any agent of the Company in defending
any proceeding prior to the final disposition of such proceeding upon receipt of
an undertaking by or on behalf of the agent to repay such amount unless it shall
be determined ultimately that the agent is entitled to be indemnified.

        The Bylaws also authorize the Company to purchase and maintain insurance
on behalf of any person who is or was a director, officer, employee or agent of
the Company against any liability asserted against or incurred by such person in
such capacity or arising out of such person's status as such, regardless of
whether the Company would have the power to indemnify such person against such
liability under the provisions of the MBCA.

        The Company has entered into an indemnification agreement with certain
of its directors, officers and other key personnel, which contains provisions
that may in some respects be broader than the specific indemnification
provisions contained under applicable law. The indemnification agreement may
require the Company, among other things, to indemnify such directors, officers
and key personnel against certain liabilities that may arise by reason of their
status or service as directors, officers or employees of the Company, to advance
the expenses incurred by such parties as a result of any threatened claims or
proceedings brought against them as to which they could be indemnified, and to
the maximum extent that insurance coverage of such directors, officers and key
employees under the Company's directors' and officers' liability insurance
policies is maintained.

        Section 1209 of the MBCA permits a Michigan corporation to include in
its Articles of Incorporation a provision eliminating or limiting a director's
liability to a corporation or its shareholders for monetary damages for breaches
of fiduciary duty. The enabling statute provides, however, that liability for
breaches of the duty of loyalty, acts or omissions not in good faith or
involving intentional misconduct or knowing violations of the law, or the
receipt of improper personal benefits cannot be eliminated or limited in this
manner. The Company's Restated Articles of Incorporation include a provision
which eliminates, to the fullest extent permitted by the MBCA, director
liability for monetary damages for breaches of fiduciary duty.

Item 7. Exemption From Registration Claimed

        Inapplicable.

Item 8. Exhibits

        See Exhibit Index.
Item 9. Undertakings

        (a)  Rule 415 Offering

        The undersigned registrant hereby undertakes:

             (1)  To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

                  (i)   To include any prospectus required by Section 10(a)(3)
of the Securities Act;

                  (ii)  To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent post-
effective amendment thereof) which, individually or in the aggregate, represent
a fundamental change in the information set forth in the registration statement;

                  (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement; provided,
however, that paragraphs (a)(1)(i) and (a)(l)(ii) do not apply if the
registration statement is on Form S-3 or Form S-8, and the information required
to be included in a post-effective amendment by those paragraphs is contained in
periodic reports filed by the registrant pursuant to Section 13 or Section 15(d)
of the Exchange Act that are incorporated by reference in the registration
statement.

             (2)  That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

             (3)  To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

        (b)  Filing incorporating subsequent Exchange Act documents by reference

        The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to Section 15(d) of the Exchange Act) that is
incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

        (h)  Request for acceleration of effective date or filing of
registration statement on Form S-8
Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
registrant pursuant to the foregoing provisions, or otherwise, the registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore, unenforceable. In the event that a claim for indemnification
against such liabilities (other than the payment by the registrant of expenses
incurred or paid by a director, officer or controlling person of the registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.
SIGNATURE

     Pursuant to the requirements of the Securities Act, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Ann Arbor, State of Michigan, on June 8, 2000.

                                        AASTROM BIOSCIENCES, INC.

                                        By: /s/ R. Douglas Armstrong
                                           -------------------------------------
                                           R. Douglas Armstrong, Ph.D.
                                           President and Chief Executive Officer
POWER OF ATTORNEY

     The officers and directors of Aastrom Biosciences, Inc. whose signatures
appear below, hereby constitute and appoint R. Douglas Armstrong, and Todd E.
Simpson, and each of them, their true and lawful attorneys and agents, with full
power of substitution, each with power to act alone, to sign and execute on
behalf of the undersigned any amendment or amendments to this registration
statement on Form S-8, and each of the undersigned does hereby ratify and
confirm all that each of said attorney and agent, or their or his substitutes,
shall do or cause to be done by virtue hereof.

     Pursuant to the requirements of the Securities Act this registration
statement has been signed by the following persons in the capacities indicated
on June 8, 2000.
Signature                                                   Title
----------------------------------------------------------- --------------------------------------------------------
/s/ R. Douglas Armstrong                                    President, Chief Executive Officer and Director
-------------------------------------------------------     (Principal Executive Officer)
R. Douglas Armstrong, Ph.D.

/s/ Todd E. Simpson                                         Vice President, Finance and Administration and Chief
-------------------------------------------------------     Financial Officer (Principal Financial and Accounting
Todd E. Simpson                                             Officer)

/s/ Mary L. Campbell                                        Director
-------------------------------------------------------
Mary L. Campbell

/s/ Stephen E. Emerson                                      Director
-------------------------------------------------------
Stephen E. Emerson, M.D., Ph.D.

/s/ Arthur F. Staubitz                                      Director
-------------------------------------------------------
Arthur F. Staubitz

/s/ Joseph A. Taylor                                        Director
-------------------------------------------------------
Joseph A. Taylor
EXHIBIT INDEX

 5       Opinion re legality

23.1     Consent of Counsel (included in Exhibit 5)

23.2     Consent of Independent Accountants

24       Power of Attorney (included in the signature pages to this registration
         statement)