Document:

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                                                                   EXHIBIT 10.6

                                SECOND AMENDMENT
                                     TO THE
                                  ZONAGEN, INC.
                 2000 NON-EMPLOYEE DIRECTORS' STOCK OPTION PLAN

         This Second Amendment to the Zonagen, Inc. (the "Company") 2000
Non-Employee Directors' Stock Option Plan, as amended, (the "Amendment") is
executed pursuant to Section 12 of the Company's 2000 Non-Employee Directors'
Stock Option Plan (the "Plan"). All capitalized and undefined terms used herein
shall have the meanings ascribed to such terms in the Plan.

         WHEREAS, the Company's Board of Directors (the "Board") is authorized
by Section 12 of the Plan to amend the Plan from time to time, subject to any
required stockholder approval of any such amendments; and

         WHEREAS, the Board desires to amend the Plan, effective as of June 27,
2002, to allow for issuance of stock awards and options under the Plan in order
to allow the Company to pay fees for certain meetings owed to directors in stock
awards and options in lieu of cash; and

         WHEREAS, such amendments do not require stockholder approval as set
forth in Section 12 of the Plan.

         NOW, THEREFORE, in connection with the foregoing, the Plan is hereby
amended as follows:

         1. Section 7(a) of the Plan up to but not including subsections (i) and
(ii) thereunder, which subsections shall remain, is hereby deleted in its
entirety and replaced with the following:

                  "(a) PER-MEETING FEE. The Company shall pay each Non-Employee
                  Director One Thousand Dollars ($1,000) (the "Director Fee") in
                  (x) cash, (y) shares of Common Stock; or (z) an Option (the
                  "Director Fee Option") to purchase shares of Common Stock, at
                  his or her election, for each meeting of the Board or any
                  committee of the Board at which he or she attends in person or
                  telephonically. If a Non-Employee Director elects to receive
                  Common Stock or an Option, the number of shares to be granted
                  pursuant to this Section 7(a) shall be determined in
                  accordance with the following:"

         2. Except as amended hereby, the terms and provisions of the Plan shall
remain in full force and effect, and the Plan and this Amendment shall be read,
taken and construed as one and the same instrument.

         IN WITNESS WHEREOF, and as conclusive evidence of the adoption and
approval of the foregoing Second Amendment to the Plan by the Board, the Company
has caused this Amendment to be duly executed in its name and behalf by its
proper officers thereunto duly authorized as of the 24th day of October, 2002.

                                     ZONAGEN, INC.

                                     By:  /s/ Joseph S. Podolski
                                          -------------------------------------
                                          Joseph S. Podolski,
                                          President and Chief Executive Officer<PAGE>
                                                                  EXHIBIT 10.17

                               SECOND AMENDMENT TO
                              EMPLOYMENT AGREEMENT

         This Second Amendment to Employment Agreement (the "Second Amendment")
is executed and dated effective as of the 29th day of October, 2002 between
Zonagen, Inc. (the "Company") and Joseph S. Podolski (the "Employee").

         WHEREAS, the Company and Employee entered into an Employment Agreement
dated as of January 1, 1993, as amended by the First Amendment to Employment
Agreement dated January 31, 2001 (as amended, the "Employment Agreement") which
has been renewed for successive terms pursuant to its terms;

         WHEREAS, the Company and Employee now wish to amend certain provisions
of the Employment Agreement for clarification;

         NOW THEREFORE, in consideration of the foregoing and the mutual
covenants herein, the parties hereto agree as follows:

         1. Capitalized terms used but not defined herein have the respective
meanings set forth in the Employment Agreement.

         2. Section 4(e) of the Employment Agreement is hereby amended by
replacing it in its entirety with the following:

                  "(e) In the event that Employee terminates his employment for
         Good Reason (as defined in Section 6(c) below) or Employee's employment
         is terminated by the Company without Cause within twelve months
         following a Change of Control (as defined below) of the Company, the
         Employee shall receive a cash lump sum bonus payment of the amount
         necessary to provide him with the present value of the aggregate amount
         of payments (plus interest as described below) set forth in the
         schedule below. For this purpose, such present value shall be
         determined as of the closing of the Change of Control (i) assuming that
         a termination of Employee's employment for one of the reasons described
         in the immediately preceding sentence will occur upon such closing date
         and (ii) using an annual interest rate equal to the prime rate posted
         by the bank that serves as the Employer's (or any successor's)
         principal banking connection as of the closing date of the Change of
         Control. Such bonus payment shall be in consideration for (i) past
         services and services rendered in connection with Change of Control and
         (ii) to the extent reasonable and to the extent necessary to avoid
         application of an excise tax under Section 4999 of the Internal Revenue
         Code of 1986, as amended, the consulting services required to be
         rendered by Employee during the first twelve (12) months after a Change
         of Control pursuant to Section 6(c) below. Employee agrees to defer
         payment of such lump sum bonus payment (and any earnings thereon) in
         accordance with and upon the following schedule, subject only to such
         payroll and withholding deductions as are required by applicable
         federal and state laws. Such payments shall be in lieu of any other
         severance payments payable to Employee under Section 6(a) of the
         Employment Agreement, provided however that Employee shall be entitled
         to continue to receive the benefits coverage for twelve (12) months
         following termination of employment as provided in such Section 6(a).
         All funds required

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         to be paid to Employee pursuant to the terms hereof shall be segregated
         and contributed to the irrevocable Joe Podolski Rabbi Trust, a copy of
         which is attached hereto, by the Company or the successor or acquiring
         company for the benefit of the Employee upon closing of the Change of
         Control, and maintained there (subject to the terms of such trust
         regarding insolvency of the Company) until paid pursuant to the terms
         hereof in accordance with the following schedule:

                  On the closing of the Change of Control: The Employee's then
         current monthly rate of base salary in affect on the date of closing of
         the Change of Control multiplied by twelve (12)

         On first, second, third, and fourth anniversary dates of the Change of
         Control:                                                $150,000.00

         On the fifth anniversary date of the Change of Control: $125,000.00

         On the sixth anniversary date of the Change of Control:  $75,000.00

         Such payments shall be made to Employee, or to his heirs or
         representative in the event of his death, and shall be credited with
         interest, from such due date until paid, at an annual rate equal to the
         prime rate posted by the bank that serves as the Employer's (or any
         successor's) principal banking connection as of the due date of the
         payment. Employee shall have the status of a general unsecured creditor
         of the Company with respect to the bonus payments required to be paid
         by the Company under this Section 4(e), and the Company's obligation to
         pay such bonus constitutes a mere promise by the Company to make such
         payments in the future. Employee's rights to receive such bonus
         payments shall not be subject in any manner to anticipation,
         alienation, sale, transfer, assignment, pledge, encumbrance,
         attachment, or garnishment by creditors of Employee or any beneficiary
         of Employee. It is the intention of the parties hereto that this
         deferred bonus arrangement be unfunded for tax purposes and for
         purposes of Title I of the Employee Retirement Income Security Act of
         1974, as amended, to the extent applicable.

         3. Except as amended and modified by this Second Amendment, the
Employment Agreement shall continue in full force and effect. The Employment
Agreement and this Second Amendment shall be construed as one and the same
instrument.

         4. This Second Amendment may be signed in any number of counterparts,
each of which shall be deemed an original, but all of which together shall
constitute one and the same instrument, and it shall not be necessary in making
proof of this Second Amendment to produce or account for more than one such
counterpart.

         5. This Second Amendment (i) constitutes the entire contract between
the parties relative to the amendments to the Employment Agreement made hereby,
(ii) supersedes all prior agreements, consents and undertakings relating to such
amendments and (iii) may not be contradicted by evidence of prior
contemporaneous or subsequent oral agreements of the parties.

         6. This Second Amendment shall be construed and enforced in accordance
with the laws of the State of Texas.

         7. This Second Amendment shall be binding upon and shall inure to the
benefit of and enforceable by the parties hereto and their respective successors
and assigns.

                                      -2-

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         IN WITNESS WHEREOF, the parties have executed this Second Amendment to
the Employment Agreement effective (the "Effective Date") for all purposes as of
the date first above written.

EMPLOYEE:                                    COMPANY:

                                             ZONAGEN, INC.

/s/ Joseph S. Podolski                       By:  /s/ Martin P. Sutter
---------------------------                       ---------------------------
Joseph S. Podolski                                Name:  Martin P. Sutter
                                                  Title: Chairman of the Board

                                      -3-

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