Exhibit 10.28

                  2003 NONEMPLOYEE DIRECTORS STOCK OPTION PLAN
                                       OF
                         HUMAN PHEROMONE SCIENCES, INC.

     1. PURPOSES OF THE PLAN

         The  purposes of the 2003  Nonemployee  Directors  Stock Option Plan of
Human Pheromone Sciences, Inc., a California corporation,  are: (a) to encourage
Nonemployee  Directors to accept or continue their association with the Company;
and  (b)  to  increase   their  interest  in  the  Company's   success   through
participation in the growth in value of the Common Stock of the Company. Options
granted  hereunder  shall be  "Nonstatutory  Options,"  and  shall  not  include
"incentive  stock options"  intended to qualify for treatment under Sections 421
and 422 of the Internal Revenue Code of 1986, as amended.

     2. DEFINITIONS

         As used herein, the following definitions shall apply:

         (a)  "Administrator"  shall  mean the  entity,  either  the  Board or a
committee  appointed by the Board,  responsible for administering  this Plan, as
provided in Section 5.

         (b)  "Affiliate"  shall  mean a parent  or  subsidiary  corporation  as
defined in the applicable provisions of the Code.

         (c) "Annual Option" shall have the meaning set forth in Section 6(b).

         (d)  "Board"  shall  mean the Board of  Directors  of the  Company,  as
constituted from time to time.

         (e) "Change in  Control"  shall mean the  occurrence  of any one of the
following:

     (i) any "person",  as such term is used in Sections  13(d) and 14(d) of the
Exchange  Act (other  than the  Company,  an  Affiliate,  or a Company  employee
benefit  plan,  including  any  trustee of such plan  acting as  trustee)  is or
becomes the  "beneficial  owner" (as  defined in Rule 13d-3  under the  Exchange
Act), directly or indirectly,  of securities of the Company  representing 20% or
more of the combined voting power of the

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Company's then outstanding securities;

     (ii) the solicitation of proxies (within the meaning of Rule 14a-1(k) under
the Exchange Act and any successor  rule) resulting in the election of directors
constituting  a majority of the board of  directors  of the Company who were not
candidates  proposed by a majority  of the Board in office  prior to the time of
such election; or

     (iii) the dissolution or liquidation (partial or total) of the Company or a
sale of assets involving 50% or more of the assets of the Company, or any merger
or reorganization of the Company, whether or not another entity is the survivor,
or other  transaction  pursuant to which the holders,  as a group, of all of the
shares of the Company  outstanding  prior to the  transaction  hold, as a group,
less than 50% of the shares of the Company outstanding after the transaction.

         (f) "Code" shall mean the Internal Revenue Code of 1986, as amended.

         (g) "Common Stock" shall mean the Common Stock of the Company.

         (h) "Company"  shall mean Human Pheromone  Sciences,  Inc, a California
corporation.

         (i)  "Exchange  Act"  means the  Securities  Exchange  Act of 1934,  as
amended from time to time, and any successor statute.

         (j) "Fair  Market  Value" shall mean,  as of the date in question,  the
last  transaction  price  quoted  by  the  Nadsaq  Stock  Market  or on  another
established stock exchange or quoted on any established interdealer quotation or
bulletin  board system,  on the date of grant;  provided,  however,  that if the
Common Stock is not so traded or the foregoing shall otherwise be inappropriate,
then the Fair Market  Value shall be  determined  by the  Administrator  in good
faith at its sole  discretion  and on such basis as it shall  deem  appropriate.
Such determination shall be conclusive and binding on all persons.

         (k) "Initial Option" shall have the meaning set forth in Section 6(a).

         (l) "Nonemployee Director" shall mean any person who is a member of the
Board but is not an employee of the Company or any Parent or  Subsidiary  of the
Company and has not been an employee of the Company or any Parent or  Subsidiary
of the Company at any time during the preceding 12 months.

         (m) "Option" shall mean a stock option granted pursuant to this Plan.

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         (n) "Option  Agreement" shall mean the written  agreement  described in
Section 6(c)  evidencing  the grant of an Option to a  Nonemployee  Director and
containing the terms, conditions and restrictions pertaining to such Option.

         (o) "Option  Shares" shall mean the Shares subject to an Option granted
under this Plan.

         (p) "Optionee" shall mean a Nonemployee Director who holds an Option.

         (q)  "Parent"  shall  mean  a  "parent  corporation,"  whether  now  or
hereafter existing, as defined in Section 424(e) of the Code.

         (r) "Plan" shall mean this 2003 Nonemployee Directors Stock Option Plan
of Human Pheromone Sciences, Inc., as it may be amended from time to time.

         (s) "Rule 16b-3" shall mean Rule 16b-3  promulgated  by the  Securities
and Exchange Commission, or any successor rule thereto.

         (t) "Section"  unless the context clearly  indicates  otherwise,  shall
refer to a Section of this Plan.

         (u)  "Share"  shall  mean a share  of  Common  Stock,  as  adjusted  in
accordance with Section 7(a).

         (v) "Subsidiary" shall mean a "subsidiary  corporation" of the Company,
whether now or hereafter  existing,  within the meaning of Section 424(f) of the
Code, but only for so long as it is a "subsidiary corporation".

     3. ELIGIBLE PERSONS

         Every  person  who at the date of grant of an Option  is a  Nonemployee
Director  is eligible to receive  Options  under this Plan and only  Nonemployee
Directors may receive Options under this Plan.

     4. STOCK SUBJECT TO THIS PLAN

         (a) Subject to Section 7(a) of this Plan, the maximum  aggregate number
of Shares  which may be issued on exercise of Options  granted  pursuant to this
Plan is  300,000  Shares.  Such  shares  may  consist,  in whole or in part,  of
authorized and unissued shares or shares  reacquired in private  transactions or
open market purchases, but all shares issued under the Plan regardless of source
shall be counted against the 300,000

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share limitation. If any Option terminates or expires without being exercised in
full,  the shares  issuable  under such  Option  shall  again be  available  for
issuance in  connection  with other  Options.  If shares of Common  Stock issued
pursuant to an Option are  repurchased  by the Company,  such Common Stock shall
not again be available  for issuance in connection  with Options.  To the extent
the number of shares of Common Stock issued  pursuant to an Option is reduced to
satisfy  withholding tax  obligations,  the number of shares withheld to satisfy
the withholding tax obligations shall not be available for later grant under the
Plan.

         (b) An Optionee  shall have no rights as a shareholder  with respect to
any Shares  covered by his or her Option until the issuance (as evidenced by the
appropriate  entry on the books of the Company or its duly  authorized  transfer
agent) of a stock certificate  evidencing such Shares.  Subject to Section 7(a),
no adjustment shall be made for dividends (ordinary or extraordinary, whether in
cash,  securities or other property),  distributions,  or other rights for which
the record date is prior to the date the certificate is issued.

     5. ADMINISTRATION

         (a) This Plan shall be  administered  by the Board,  or by a  committee
(the "Committee") of at least two Board members who are Nonemployee Directors to
which   administration   of  the  Plan  is  delegated   (in  either  case,   the
"Administrator"), in accordance with the requirements of Rule 16b-3.

         (b) Subject to the other  provisions  of this Plan,  the  Administrator
shall have the  authority,  in its sole  discretion:  (i) to determine  the Fair
Market Value of the Shares subject to Option; (ii) to interpret this Plan; (iii)
to  prescribe,  amend and rescind rules and  regulations  relating to this Plan;
(iv) to defer (with the consent of the Optionee) or accelerate the exercise date
of any Option;  (v) to authorize  any person to execute on behalf of the Company
any  instrument  evidencing  the grant of an Option;  and (vi) to make all other
determinations  deemed  necessary or advisable  for the  administration  of this
Plan. The Administrator may delegate  nondiscretionary  administrative duties to
such employees of the Company as it deems proper.

         (c) All questions of interpretation,  implementation and application of
this Plan shall be determined by the Administrator.  Such determination shall be
final and binding on all persons.

     6. GRANT OF OPTIONS

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         (a) Grant for Initial Election or Appointment to Board.  Subject to the
terms and  conditions  of this Plan,  beginning at any time after the  Company's
2003 Annual  Stockholder's  meeting if any person who qualifies as a Nonemployee
Director  as defined  herein is first  elected or  appointed  as a member of the
Board, then the Company shall grant to such Nonemployee  Director on such day an
Option to purchase 20,000 Shares  ("Initial  Option") at an exercise price equal
to the Fair  Market  Value of such  Shares  on the date of such  Initial  Option
grant, subject to the limitation of Section 7(i).

         (b) Grant for Re-election to Board. Subject to the terms and conditions
of this  Plan,  on the  date  of the  first  meeting  of the  Board  immediately
following each annual meeting of stockholders of the Company  beginning with the
Company's 2003 Annual Stockholders  Meeting (even if held on the same day as the
meeting of stockholders)  the Company shall grant to each  Nonemployee  Director
then in office for longer than six months,  an Option to purchase  20,000 shares
(the  "Annual  Option") at an exercise  price equal to the Fair Market  Value of
such Shares.

         (c) Optional Grants.  Subject to the terms and conditions of this Plan,
the  Administrator,  at its sole  discretion,  may grant an  Option to  purchase
shares of the  Company's  Common  Stock at an  exercise  price equal to the Fair
Market  Value of such  Shares  to any  Nonemployee  Director  from time to time.
Nothing in this Section shall confer upon any Nonemployee  Director any right to
receive any  additional  Options  other than the  Initial  Option and the Annual
Option.

         (d) No Option  shall be granted  under this Plan after seven years from
the date of adoption of this Plan by the Board.  Each Option  shall be evidenced
by a  written  Option  Agreement,  in form  and  substance  satisfactory  to the
Company,  executed by the Company and the Optionee.  Failure by the Company, the
Nonemployee  Director,  or  both  to  execute  an  Option  Agreement  shall  not
invalidate the granting of an Option;  however,  the Option may not be exercised
until the Option Agreement has been executed by both parties.

     7. TERMS AND CONDITIONS OF OPTIONS

         Each Option  granted  under this Plan shall be subject to the terms and
conditions set forth in this Section 7.

         (a) Changes in Capital  Structure.  Subject to subsection  7(b), if the
Common Stock is changed by reason of a stock split,  reverse stock split,  stock
dividend,  or  recapitalization,  or  converted  into  or  exchanged  for  other
securities  as  a  result  of  a  merger,   consolidation,   or  reorganization,
appropriate  adjustments shall be made in: (i) the number and class of shares of
stock subject to this Plan and each Option outstanding

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under  this  Plan;  and (ii) the  exercise  price  of each  outstanding  Option;
provided,  however,  that the Company shall not be required to issue  fractional
shares as a result of any such adjustment. Each such adjustment shall be subject
to approval by the Administrator in its sole discretion.

         (b) Time of Option  Exercise.  Subject to the other  provisions of this
Plan,  each Option shall be for a term of seven years.  Each Option shall become
exercisable  with respect to one-twelfth of the number of Shares covered by such
Option on the first day of each month  following the date of grant, so that such
Option shall be fully exercisable twelve months after the first day of the month
following the date of grant.

         (c)  Limitation  on  Other  Grants.  The  Administrator  shall  have no
discretion  to grant Options under this Plan other than as set forth in Sections
6(a), 6(b) and 6(c).

         (d)  Nonassignability of Option Rights.  Unless determined otherwise by
the Administrator in its absolute  discretion,  no Option shall be assignable or
otherwise  transferable  by the Optionee,  except by will or the laws of descent
and  distribution,  and  during  the life of an  Optionee,  an  Option  shall be
exercisable only by the Optionee.

         (e) Payment.  Except as provided below, payment in full, in cash, shall
be made for all Option Shares  purchased at the time written  notice of exercise
of an  Option  is  given to the  Company,  and  proceeds  of any  payment  shall
constitute  general  funds of the  Company.  At the time an Option is granted or
exercised,  the  Administrator,  in its absolute  discretion,  may authorize (i)
delivery by the Optionee of Common Stock  already  owned by the Optionee for all
or part of the Option price, provided the Fair Market Value of such Common Stock
is equal on the date of exercise to the Option price, or such portion thereof as
the Optionee is authorized to pay by delivery of such stock; provided,  however,
that if an  Optionee  has  exercised  any  portion of any Option  granted by the
Company by delivery of Common  Stock,  the Optionee  may not,  within six months
following such exercise, exercise any Option granted under this Plan by delivery
of Common Stock,  (ii) the  consideration  to be received by the Company under a
"cashless  exercise/sale"  procedure or program  implemented  or approved by the
Company  in  connection  with the Plan,  and (iii) any other  consideration  and
method of payment to the extent permitted under the California Corporation Code.

         (f)  Termination  as  Director.  Unless  determined  otherwise  by  the
Administrator in its absolute  discretion,  to the extent not already expired or
exercised,  an Option shall  terminate at the earlier of: (i) the  expiration of
the term of the Option;  or (ii) three  months  after the last day served by the
Optionee as a director of the Company;

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provided,  that an Option shall be exercisable  after the date of termination of
service as a director only to the extent exercisable on the date of termination;
and provided  further,  that if an Optionee dies or suffers a  "disability"  (as
determined in accordance  with Section  22(e)(3) of the Code) while serving as a
director (or, in the event of death,  within the period that the Option  remains
exercisable  after termination of service as a director),  the Optionee,  or the
Optionee's personal  representative (or any other person who acquires the Option
from the Optionee by will or the applicable  laws of descent and  distribution),
may at any time within 12 months after the  termination of service as a director
(or such lesser  period as is specified in the Option  Agreement but in no event
after the  expiration  of the term of the  Option),  exercise  the rights to the
extent they were exercisable on the date of the termination.

         (g)  Withholding  and Employment  Taxes.  At the time of exercise of an
Option  (or at such later  time(s)  as the  Administrator  may  prescribe),  the
Optionee  shall  remit to the Company in cash all  applicable  federal and state
withholding and employment taxes. If authorized by the Administrator in its sole
discretion,  an  Optionee  shall be  permitted  to elect,  by means of a form of
election to be prescribed by the  Administrator,  to have shares of Common Stock
which are  acquired  upon  exercise of the Option  withheld by the Company or to
tender to the Company  other shares of Common Stock or other  securities  of the
Company owned by the Optionee on the date of  determination of the amount of tax
to be  withheld  as a result of the  exercise of such Option (the "Tax Date") to
pay the amount of withholding  taxes due. Any securities so withheld or tendered
shall be valued by the Company as of the Tax Date.

         (h) Option Term. Each Option shall expire seven years after the date of
grant.

     8. EFFECT OF CHANGE IN CONTROL.

         In the event of a "Change in Control,"  any Options  outstanding  as of
the date such  Change in Control is  determined  to have  occurred  and not then
exercisable and vested shall become fully exercisable and vested.

     9. MANNER OF EXERCISE

         (a) An Optionee wishing to exercise an Option shall give written notice
to the  Company at its  principal  executive  office,  to the  attention  of the
officer of the Company designated by the  Administrator,  accompanied by payment
of the exercise  price as provided in Section 7(e) and, if required,  by payment
of any federal or state  withholding or employment taxes required to be withheld
due to exercise of the Option.  The date the Company  receives written notice of
an exercise accompanied by payment of

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the exercise price and any required  federal or state  withholding or employment
taxes will be considered as the date such Option was exercised. Unless otherwise
provided  by the  Administrator,  Options  may be  exercised  only  twice in any
calendar year.

         (b) Promptly after the date an Option is exercised,  the Company shall,
without stock issue or transfer  taxes to the optionee or other person  entitled
to  exercise  the  Option,  deliver  to the  Optionee  or such  other  person  a
certificate or certificates  for the requisite number of shares of Common Stock.
An Optionee or  transferee  of an Optionee  shall not have any  privileges  as a
stockholder  with  respect to any Common  Stock  covered by the Option until the
date of issuance of a stock certificate.

     10. NO RIGHT TO DIRECTORSHIP

         Neither  this Plan nor any Option  shall  confer upon any  Optionee any
right with respect to continuation of the Optionee's  membership on the Board or
shall  interfere in any way with  provisions  in the  Company's  Certificate  of
Incorporation,  as amended,  and Bylaws,  as amended,  relating to the election,
appointment, terms of office, and removal of members of the Board.

     11. LEGAL REQUIREMENTS

         The  Company  shall not be  obligated  to offer or sell any Shares upon
exercise of any Option unless the Shares are at that time effectively registered
or exempt from registration  under the federal securities laws and the offer and
sale of the Shares are otherwise in compliance  with all  applicable  securities
laws and the regulations of any stock exchange on which the Company's securities
may then be listed.  The Company shall have no obligation to register the Shares
covered by this Plan under the federal  securities  laws or take any other steps
as may be necessary to enable the Shares  covered by this Plan to be offered and
sold under federal or other  securities laws. Upon exercising all or any portion
of an  Option,  an  Optionee  may be  required  to  furnish  representations  or
undertakings  deemed  appropriate by the Company to enable the offer and sale of
the Shares or subsequent  transfers of any interest in the Shares to comply with
applicable  securities  laws.   Certificates  evidencing  Shares  acquired  upon
exercise of Options shall bear any legend required by, or useful for purposes of
compliance with, applicable securities laws, this Plan or the Option Agreements.

     12. AMENDMENTS TO PLAN

         The Board may amend this Plan at any time.  Without  the  consent of an
Optionee,  no amendment may adversely affect outstanding  Options.  No amendment
shall

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require   stockholder   approval  unless  the  Board  otherwise  concludes  that
stockholder approval is advisable.

     13. TERM

         This  Plan  shall  become  effective  upon  adoption  by the  Board  of
Directors.  This Plan shall  terminate  seven years after  adoption by the Board
unless terminated earlier by the Board. The Board may terminate this Plan at any
time.  No  Options  shall  be  granted  after  termination  of  this  Plan,  but
termination  shall not affect  rights  and  obligations  under  then-outstanding
Options.


Adopted by the Board of Directors:  June 25, 2003

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