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                                                                 EXHIBIT 10.5.1

        AMENDMENT NO. 1 RESEARCH, DEVELOPMENT AND COLLABORATION AGREEMENT

This Amendment No. 1 to Research, Development and Collaboration Agreement (the
"Amendment No. 1") effective as of January 1, 1999, is entered into by and
between GenVec, Inc. ("GenVec") and Warner-Lambert Company ("Warner"), and
amends that certain Research, Development and Collaboration Agreement entered
into by Warner and GenVec effective as of July 21, 1997 (the "Agreement").

1.       All capitalized terms not defined in this Amendment No. 1 shall have
the meanings given to them in the Agreement.

2.       The Agreement is hereby amended to revise Section 1.5 as follows:

         1.5 "COLLABORATION PRODUCT" shall mean a Product Configuration for
         which Development has commenced pursuant to this Agreement. On a
         country-by-country basis, a Product Configuration which has commenced
         sales shall continue to be a Collaboration Product unless Warner or its
         Affiliates or Sublicensees discontinue sales of such Collaboration
         Product in the applicable country and have no intent to resume such
         sales.

3.       The Agreement is hereby amended to revise Section 2.2.3(a) as follows:

         2.2.3    ASIAN COMPANY.

                  (a) GenVec may enter into an agreement(s) with one or more
companies for the research, development and/or commercialization of one or more
Product Configurations in Japan or other countries outside the Territory and the
Co-Promotion Countries, any such company (an "Asian Partner" and collectively,
the "Asian Partners") shall have the right to obtain access to and the right to
use the Data Package for the purpose of seeking Regulatory Approval for any
Product Configurations for any indication to which the Asian Partner has
commercialization rights in Japan and/or any other country, subject to Section
15.2. Notwithstanding the foregoing, Warner shall only be obligated to provide
each component of the Data Package a single time and GenVec shall designate
which of GenVec or the Asian Partners shall be the party to whom Warner shall
provide the Data Package components; provided, however, that the party receiving
the Data Package may provide the Data Package to GenVec and one or more other
Asian Partners, and GenVec (or its Asian Partner designee) shall reasonably seek
to minimize the number and frequency of requests for the components of the Data
Package. In exchange for receiving such access and rights, the Asian Partner(s)
must agree to pay to Warner amounts to be agreed by Warner and the Asian
Partner(s), which shall not, in the aggregate, exceed one-fourth of all costs
incurred in connection with those aspects of the Research Program or the
Development in which data contained in the Data Package was generated or
obtained. In addition to the payment to Warner described above, each Asian
Partner shall be obligated to pay all expenses it incurs in conducting research
and development activities with respect to any Product Configuration
specifically and solely for obtaining Regulatory Approvals in Japan and/or any
other country for which it has commercialization rights.


[*] = CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY
      WITH THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH
      RESPECT TO THE OMITTED PORTIONS. OMITTED TEXT IS INDICATED BY A "*".

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4.       The Agreement is hereby amended to revise Section 1.27 by amending
the formula therein to read as follows:
         Average percentage
         discount on a                      =  (1-A/B) x 100
         particular "bundle"

5.       The Agreement is hereby amended by adding the following clause to
the beginning of the first sentence of Section 4.5.1: "Subject to the terms
of Section 6.3.5, and . . ."

6.       The Agreement is hereby amended to add the following to the end of
Section 6.1:

         On or before March 20, 1999, Warner shall pay to GenVec the amount of
         three million seven hundred fifty thousand dollars ($3,750,000).

7.       The Agreement is hereby amended to revise Section 6.3 by the addition
         of new Section 6.3.5:

         6.3.5 REIMBURSEMENT. On or before March 20, 1999, Warner shall pay to
         GenVec one million two hundred fifty thousand dollars ($1,250,000) as
         reimbursement of certain Development Costs described on Exhibit A
         hereto incurred by GenVec in the period July 1, 1997 through December
         31, 1998 with respect to Collaboration Products. No further Development
         Costs shall be owed to GenVec by Warner for the period July 1, 1997
         through December 31, 1998. Each year the Executive Committee shall
         approve a twelve (12) month budget for all Development Costs
         anticipated to be incurred by GenVec and reimbursed by Warner (the
         "Budget"). The Executive Committee shall review such Budget every six
         (6) months. Except as specifically approved in the Budget, after
         December 31, 1998, GenVec shall not receive funding for any Development
         Costs in excess of the funds paid by Warner pursuant to Sections 6.3 or
         11.7, without the prior written consent of the Executive Committee or a
         Warner designee and only such pre-approved Development Costs shall be
         reimbursed to GenVec by Warner. For any of the above approved
         Development Costs in excess of the funds paid by Warner pursuant to
         Sections 6.3 or 11.7, GenVec shall be reimbursed by Warner for
         Development Costs, if any, incurred by GenVec up to a maximum of 110%
         of the approved amount. GenVec shall further not expend any of the
         funds received by it under Sections 6.3.1, 6.3.2 and 11.7 for
         Development Costs except pursuant to the Budget. In the event that
         GenVec believes that additional Development funding in excess of 110%
         of that approved by the Executive Committee is required or desirable
         for the conduct of activities to be conducted by GenVec in connection
         with the Development, it may notify the Executive Committee; provided,
         Warner shall have no obligation to reimburse GenVec for any such excess
         without the prior written approval of the Executive Committee or a
         Warner designee.

8.       Section 6.4.1 of the Agreement is hereby revised to restate the
third and fourth milestone payments due to GenVec for the "Filing of a PLA"
with respect to Collaboration Products for the first occurrence for each of
CAD and PVD as follows:

                                                                           -2-
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         Filing of a PLA *
         Filing of a PLA *

         All other milestones set forth in Section 6.4.1 shall remain unchanged.

9.       Section 6.5.1 of the Agreement is hereby revised to replace the
following :

                  "Annual Net Sales up to *
                  Annual Net Sales over *

         with the following new description of royalties:

                  "Annual Net Sales up to *
                  Annual Net Sales over *
                  and less than or equal *
                  Annual Net Sales above *

10.       Section 6.5.4 of the Agreement is hereby amended to replace the
words "*" with the words "*".

11.       The Agreement is hereby amended to revise Section 6.6.2 to provide
in its entirety as follows:

         Except as expressly provided in Sections 6.6.1 or 6.6.3, Warner shall
         be responsible for the payment of all royalties, license fees and
         milestone and other payments due from GenVec or Warner to any Third
         Party(ies) under licenses or similar agreements (including license or
         similar agreement entered into by GenVec only if approved by the
         Executive Committee) for the manufacture, use, import, or sale of
         Collaboration Products in the Territory; provided, if the Executive
         Committee fails to approve a particular license or other agreement(s)
         with a Third Party, Warner shall have no rights to any intellectual
         property or other subject matter within the scope of such agreements,
         and GenVec shall have no liability under this Agreement for not
         providing such rights to Warner.

12.       The Agreement is hereby amended to revise Section 6.6.3 to provide
in its entirety as follows:

         6.6.3 SHARED RESPONSIBILITIES. Subject to Section 6.5.4, in the event
         that (y) the aggregate amount paid or otherwise due or owing by Warner
         for royalties with respect to a particular Collaboration Product (i) to
         GenVec for royalties pursuant to Section 6.5.1, and (ii) for royalty
         payments to Third Parties pursuant to Section 6.6.2, and (z) the Cost
         of Manufacture of such Collaboration Product, in the aggregate, exceed
         thirty percent (30%) of the Net Sales of such Collaboration Product,
         then Warner and GenVec shall equally share the portion of the aggregate
         of the payments for (y) and (z) by Warner which are in excess of thirty
         percent (30%) of Net Sales of the applicable Collaboration Product, to
         the extent such payments in excess of thirty percent (30%) of Net Sales
         are attributable to (y) (ii) above. It is understood and agreed that
         Warner shall be solely responsible for any such payment obligations for
         (y) and (z) which in the aggregate are less than or equal to thirty
         percent (30%) of the Net Sales

                                                                           -3-
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         of the applicable Collaboration Product. In each such case, such
         determination shall be made on a country-by-country basis and Warner
         shall provide to GenVec documentation establishing the royalty due to
         the Third Party(ies) and the Cost of Manufacture, in each case, with
         respect to the applicable Collaboration Product and the payment due
         from GenVec with respect thereto at least thirty (30) days before such
         amount is due.

13.      The Agreement is hereby amended to revise Section 11.1 by deleting
Section 11.1.

14.      Section 11.2.1 is amended to provide in its entirety as follows:

         11.2.1     Warner shall control all issues relating to, and shall have
                    the sole right to, at its expense, manufacture or have
                    manufactured Bulk Product and Finished Product for clinical
                    use and for commercial sale in the Territory and in any or
                    all Co-Promotion Countries. All costs associated with the
                    qualification or validation of Warner or a Third Party
                    manufacturer for the production of such Bulk Product and
                    Finished Product for sale in the Territory and in the
                    Co-Promotion Countries, pursuant to this Section 11.2 shall
                    be borne by Warner, subject to the terms of Section 9 and
                    Exhibit B as they relate to reimbursement of Warner's
                    Development Costs. If Warner provides GenVec notice that
                    Warner wishes to assume the performance of those activities
                    being conducted by GenVec as of March 12, 1999 with respect
                    to the manufacture of Collaboration Products, GenVec and
                    Warner agree to cooperate in good faith to transfer such
                    activities to Warner. With respect to any agreements entered
                    by GenVec on or before March 12, 1999 which relate solely to
                    Collaboration Products for the manufacture of clinical or
                    commercial supplies of Bulk Product or Finished Product with
                    Third Parties, GenVec shall promptly provide Warner with a
                    list of, and where it legally may do so, copies of all such
                    agreements, and at Warner's request, shall (i) assign such
                    agreements to Warner, if it has the right to do so without
                    incurring a penalty, or (ii) otherwise terminate such
                    agreements as soon as practicable, provided GenVec shall
                    have no obligation to terminate any such agreement if it
                    would incur a penalty for doing so. At Warner's written
                    request and expense for out-of-pocket costs, GenVec shall
                    promptly supply to Warner substantially all written and
                    electronic records in its control or possession relating to
                    the manufacture of Bulk Product or Finished Product for
                    clinical trials and shall provide reasonable assistance to
                    Warner in interpreting such information; provided, GenVec
                    shall not be in breach of this Agreement if after GenVec
                    makes a good faith effort to comply with the foregoing
                    obligation to supply records, GenVec supplies substantially
                    all, but not all such records.

15.      The Agreement is hereby amended to revise Sections 11.3, 11.4 and
11.5 by deleting the existing Sections and replacing them with the following:

         11.3     WARNER'S RIGHT TO IDENTIFY AND QUALIFY SECOND SOURCE FOR BULK
                  PRODUCT.  [deleted]

         11.4     USE OF SECOND SOURCE FOR BULK PRODUCT.  [deleted]

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         11.5     Terms of Manufacture and Supply.  [deleted]

16.      The Agreement is hereby amended to revise Article 11 by the addition
of the following new Sections:

         11.7 PROCESS DEVELOPMENT. GenVec shall be responsible for the conduct
         of activities for the development of a manufacturing process for Bulk
         Products according to the activity schedule attached as Exhibit B
         hereto, as may be amended by the written agreement of the Executive
         Committee. At Warner's expense for out-of-pocket costs, GenVec shall
         supply Warner with both electronic and hard copies of substantially all
         information and data arising out of such activities, Warner and GenVec
         shall meet promptly after March 15, 1999 to discuss the frequency of
         such information and data transfers and Warner shall indicate what
         information and/or data, if any, it does not desire to receive. GenVec
         shall provide Warner with reasonable assistance in interpreting such
         information and data. In consideration for such activities, Warner
         shall pay GenVec               *          , in accordance with
         the payment schedule, and subject to the achievement of the milestone
         set forth on Exhibit C, a total of *.
         GenVec shall not be obligated to expend amounts or incur costs on such
         activities in excess of the * received from Warner, unless
         otherwise agreed in writing by the Executive Committee. Warner shall
         have the right to visit GenVec's facilities during reasonable business
         hours and upon reasonable advance notice, to inspect GenVec's
         facilities and applicable records to confirm that the amounts being
         paid under this Section 11.7 are being expended by GenVec and are
         intended for the development of a manufacturing process for the Bulk
         Product.

         11.8 COOPERATION. At GenVec's written request, Warner shall provide
         GenVec with reasonable cooperation and assistance to establish, qualify
         and validate, at GenVec's election, GenVec and/or a Third Party
         manufacturer to manufacture requirements of Collaboration Products for
         clinical and commercial use outside the Territory and the Co-Promotion
         Countries. GenVec shall reimburse Warner for Warner's reasonable
         out-of-pocket costs incurred in providing such cooperation and
         assistance. In addition, if Warner wishes to have a Third Party
         manufacture Bulk Product within the United States for use within the
         Territory, it shall consider, but shall have no obligation to enter
         into any agreement to utilize GenVec to supply any such Bulk Product,
         for compensation to be reasonably agreed by Warner and GenVec.

         11.9 WARNER MANUFACTURING TECHNOLOGY. All manufacturing and related
         technology developed by Warner or its Affiliates or a Third Party on
         behalf of Warner with respect to any one or more Collaboration
         Products, to the extent applicable to the manufacture of gene therapy
         products and directly developed as a result of such activities
         ("Manufacturing Technology"), shall be treated as follows: With respect
         to any such Manufacturing Technology solely developed by Warner in the
         period from January 1, 1999 until December 31, 2000, GenVec shall have
         a non-exclusive, fully paid-up, royalty-free, worldwide license (with
         the right to sublicense, but only to the extent required to permit a
         Third Party or an Affiliate of GenVec to manufacture products,
         including without limitation, Collaboration Products pursuant to the
         license granted in this sentence), to make, have made, use, import,
         offer for sale and sell Collaboration Products outside the Territory
         and products

                                                                           -5-
<PAGE>

         other than Collaboration Products, subject to Article 15. With
         respect to such Manufacturing Technology solely developed by Warner
         in the period from January 1, 2001 to December 31, 2001, GenVec
         shall have a non-exclusive, worldwide license thereto (with the
         right to sublicense, but only to the extent required to permit a
         Third Party or an Affiliate of GenVec to manufacture products,
         including without limitation, Collaboration Products pursuant to the
         license granted in this sentence), to make, have made, use, import,
         offer for sale and sell Collaboration Products outside the Territory
         and products other than Collaboration Products, subject to Article
         15; provided GenVec's payment obligations under such a license shall
         be * of the applicable product. Net sales for such purpose shall be
         based on the definition in Section 1.27 and calculated in accordance
         with Section 1.27 (with appropriate contextual adjustments). GenVec
         shall have no rights in any Manufacturing Technology developed by
         Warner after December 31, 2001, but any licenses granted prior to
         such date shall remain in effect after December 31, 2001; provided,
         that if process development with respect to a Collaboration Product
         continues after December 31, 2001 the foregoing dates in this
         Section 11.9 shall be extended until the date determined by the
         Executive Committee to have been the date on which such process
         development ceased. Notwithstanding the foregoing and any other
         provision of this Agreement, it is understood and agreed that GenVec
         may make, have made and use (but not sell or permit to be sold or
         used in any human clinical trials) Collaboration Products in the
         Territory to facilitate its ability to enter into an agreement with
         the Asian Partner and to develop and commercialize Collaboration
         Products with the Asian Partner.

17.      The Agreement is hereby amended to revise Article 12 by the addition of
the following new Section 12.6:

         12.6     ACCESS.

                  (a) Until the first commercial sale of a Collaboration
                  Product, Warner shall provide GenVec and its sublicensees with
                  such data, documents and information as GenVec may reasonably
                  believe is required to be submitted to a regulatory agency in
                  connection with regulatory filings or audits or inspections by
                  an Agency, including, without limitation, a right of reference
                  or authorization to any Collaboration Product approvals,
                  and/or modifications made by Warner to the manufacturing
                  process developed by GenVec as described in Section 11.7,
                  subject to Section 2.2.3 and Section 15.2. GenVec shall pay
                  Warner reasonable costs necessary to provide such access and
                  use.

                  (b) After the first commercial sale of a Collaboration
                  Product, Warner shall provide GenVec and its sublicensees with
                  such data, documents and information as GenVec or its designee
                  is required to be submitted to a regulatory agency in
                  connection with regulatory filings or audits or inspections by
                  an Agency.

                  (c) It is understood and agreed that GenVec may only use the
                  data, information and documents made available pursuant to
                  Sections 12.5(a) and (b) above for the development and
                  commercialization of (i) Collaboration Products outside the
                  Territory and (ii) for products other than Collaboration
                  Products.

                                                                           -6-
<PAGE>

18.      The Agreement is hereby amended to revise Section 14.1.1 to provide
in its entirety as follows:

         14.1.1   BACKGROUND TECHNOLOGY.

                  (a) Except as otherwise set forth herein, each Party shall
                  retain ownership or Control, as the case may be, over its
                  Background Technology. The owner of any patentable Background
                  Technology shall have the right, at its option and expense, to
                  prepare, file and prosecute in its own name any patent
                  applications with respect to such Background Technology and to
                  maintain any patents issued thereon.

                  (b) Notwithstanding Section 14.1.1(a) above, GenVec agrees to
                  keep Warner reasonably informed of the countries in which
                  GenVec intends to seek and maintain patent protection with
                  respect to Background Technology owned or Controlled by
                  GenVec. Warner shall have the right to request GenVec to seek
                  or maintain patent protection with respect to Background
                  Technology in countries in which GenVec does not intend to
                  seek or continue to maintain patent protection (each an
                  "Additional Country"). In such event, GenVec may elect to seek
                  or maintain patent protection in the Additional Countries in
                  GenVec's name and at Warner's expense. Warner shall pay GenVec
                  the amount due for any such activities within * days
                  of receipt of an invoice therefor. All amounts paid by Warner
                  in connection with such activities in the Additional Countries
                  shall be credited, on an Additional Country-by-Additional
                  Country and Collaboration Product-by-Collaboration Product
                  basis, against royalties owed by Warner to GenVec with respect
                  to the applicable Collaboration Product(s) in the applicable
                  Additional Country. With respect to activities for which
                  Warner is paying expenses pursuant to this Section, GenVec
                  shall use patent counsel reasonably acceptable to Warner, and
                  shall keep Warner fully informed and provide the opportunity
                  for Warner to review and comment with respect to such patent
                  matters, including, without limitation, (a) providing Warner
                  with copies of all communications, including, without
                  limitation, all applications and other filings, with all
                  patent offices in sufficient advance of filing to permit
                  Warner and its patent counsel to review and comment on such
                  communications, (b) providing sufficient advance notice to
                  Warner of all meetings at all patent offices where such
                  patents and patent applications may be discussed to permit
                  Warner to attend all meetings at such patent offices, and (c)
                  providing to Warner, at Warner's request, copies of all
                  documentation (except documents subject to GenVec's
                  attorney-client privilege) relating to the filing, prosecution
                  and maintenance of all such patents and patent applications.

19.      Revise Article 17 by addition of new Section 17.5:

         17.5 OTHER DISCLOSURES. Clinical data relating to Collaboration
         Products shall be published in a timely manner upon the prior written
         consent of Warner. The publications committee under the Drug
         Development Committee shall consider all publications initially,
         provided if the publication committee does not approve the timely
         publication of any disclosure of clinical data regarding a
         Collaboration Product, GenVec may submit such matter to the

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         Executive Committee for final determination and the publication
         shall only go forward upon approval of the Executive Committee. At
         GenVec's request, and with Warner's prior written consent, which
         consent shall not be unreasonably withheld, GenVec shall be
         permitted to make reasonable disclosures in a timely manner
         regarding the status of the Development of Collaboration Products
         and related information to prospective lenders, investment bankers
         and other financial institutions of its choice for the sole purpose
         of seeking financing for its business operations.

20.      Except as specifically modified or amended hereby, the Agreement shall
remain in full force and effect and, as modified or amended, is hereby ratified,
confirmed and approved. No provision of this Amendment No. 1 may be modified or
amended except expressly in a writing signed by both parties nor shall any terms
be waived except expressly in a writing signed by the party charged therewith.
This Amendment No. 1 shall be governed in accordance with the laws of the State
of Maryland, without regard to principles of conflicts of laws.


         IN WITNESS WHEREOF, each of the parties has executed this Amendment No.
1 as of the Effective Date of this Amendment No. 1.

GENVEC, INC.                                WARNER-LAMBERT COMPANY


By:                                         By:
   ------------------------------              ------------------------------
Name:                                       Name:
     ----------------------------                ----------------------------
Title:                                      Title:
      ---------------------------                 ---------------------------


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                                   Exhibit A




                   SCHEDULE FOR REIMBURSABLE 1998 EXPENSES



                                       *


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                                   Exhibit B



                                       *

<PAGE>

                                   Exhibit C


Process Development Payment Schedule



                                       *


                              Total $10.0 million