EXHIBIT 10.15



                             FORM OF PROMISSORY NOTE
                             -----------------------


$100,000.00
                                                                November 2, 1998

      1.  AMOUNT;  MATURITY.  FOR  VALUE  RECEIVED,  the  undersigned,   GENETIC
VECTORS, INC., a Florida corporation (the "Maker"), promises to pay to JEROME P.
SEIDEN IRREVOCABLE TRUST DATED APRIL 22, 1998 (the "Holder"),  the principal sum
of One Hundred Thousand Dollars ($100,000.00),  which principal sum shall mature
on November 2, 1999 and shall bear simple interest at the rate set forth herein.

      2.  INTEREST.  Interest  shall  accrue  as of the date of this Note at the
simple interest rate of twelve percent (12%) per annum which rate shall increase
one  percent  (1%) per annum on the first day of each month that any  portion of
this Note remains unpaid after April 1, 1999 up to the maximum amount  permitted
by law.  Interest  shall be payable  monthly in arrears,  commencing on April 1,
1999 and each successive  interest payment shall be due on the first day of each
successive month thereafter.


      3.  MODE OF PAYMENT.  All  payments  of  principal and  interest due under
this Note  shall be made in legal  tender in the United  States of  America  and
delivered to the Holder at or, at the option of the Holder, in such other manner
and at such other  place as the  Holder  shall  have  designated  to the Make in
writing.

      4.  PREPAYMENT.

          (a) This Note may be voluntarily prepaid,  without penalty or premium,
in whole or in part,  at any time and from  time to time.  Any  prepayment  must
include all accrued interest on the principal being prepaid, through the date of
prepayment.

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          (b)  Notwithstanding  anything contained herein to the contrary,  this
Note shall be mandatorily prepaid in the event that the Maker closes an offering
of its securities,  whether through one or more private  placements or secondary
public offerings, in which the Maker raises gross proceeds from such transaction
or transactions of at least $3,000,000.

      5.  ACCELERATION UPON EVENT OF DEFAULT.  This Note may  be  accelerated at
the  option of the  Holder,  upon  the  occurrence of  any event  of default  as
described below:

          (a) any  default,  whether  in whole or in  part,  shall  occur in the
payment to the Holder of principal,  interest or other item  comprising the Note
as and when due which shall  continue for a period of thirty (30) days after the
receipt of written notice by the Maker thereof;

          (b) the Maker shall (1) make a general  assignment  for the benefit of
its  creditors,  (2) apply for or  consent  to the  appointment  of a  receiver,
trustee,  assignee,  custodian sequestrator,  liquidator or similar official for
itself or any of its assets and  properties,  (3) commence a voluntary  case for
relief as a debtor under the United  States  Bankruptcy  Code,  (4) file with or
otherwise  submit to any  governmental  authority any petition,  answer or other
document seeking (A) reorganization, (B) an arrangement with creditors or (C) to
take  advantage  of any  other  present  or  future  applicable  law  respecting
bankruptcy,  reorganization,   insolvency,  readjustment  of  debts,  relief  of
debtors,  dissolution or liquidation, (5) file or otherwise submit any answer or
other  document  admitting or failing to contest the material  allegations  of a
petition  or other  document  filed or  otherwise  submitted  against  it in any
proceeding  under any such  applicable  law, or (6) be adjudicated a bankrupt or
insolvent by a court of competent jurisdiction; or

          (c) any case,  proceeding  or other action shall be commenced  against
the Maker for the purpose of effecting, or an order, judgment or decree shall be
entered by any court of competent  jurisdiction  approving (in whole or in part)

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anything specified in Section 4(d) hereof, or any receiver,  trustee,  assignee,
custodian,  sequestrator,  liquidator or other  official shall be appointed with
respect to the Maker, or shall be appointed to take or shall  otherwise  acquire
possession or control of all or a substantial  part of the assets and properties
of the Maker, and any of the foregoing shall continue unstayed and in effect for
any period of 60 days.

      6.  DELAY IN  EXERCISE  OF  RIGHTS.  No delay on the part of the Holder in
exercising  any of its  options,  powers or  rights  nor any  partial  or single
exercise of its options, power or rights shall constitute a waiver thereof or of
any other option, power or right, and no waiver on the part of the Holder of any
of its options,  powers or rights shall constitute a waiver of any other option,
power or right.

      7.  WAIVER OF PRESENTMENT; NO OFFSETS. The Maker hereby waives presentment
for payment, dishonor, protest, notice of protest and any demand whatsoever with
respect  to this Note and the right to  interpose  any  defense  based  upon any
statute of limitation or any claim of laches and any set-off or  counterclaim of
any nature or description.  

      8.  COLLECTION COSTS; MAXIMUM INTEREST LIMITATIONS.

          (a) The  Maker  agrees  to pay all  reasonable  costs,  including  all
reasonable  attorneys'  fees  and  disbursements   incurred  by  the  Holder  in
collecting or enforcing payment of this Note in accordance with its terms.

          (b)  After  this  Note   becomes   due,  at  stated   maturity  or  on
acceleration,  any unpaid  balance hereof shall  thereafter  bear interest until
paid at a rate of 16% simple  interest per annum,  but such  interest rate shall
not exceed at any time the maximum  interest  rate  allowable  under  applicable
state usury laws.


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      9.  GOVERNING LAW.

          (a)  This  Note  and the  rights  of the  parties  hereunder  shall be
governed by and construed in  accordance  with the laws of the State of Florida,
without regard to its conflicts of law principles.  All parties hereto (1) agree
that any legal  suit,  action or  proceeding  arising out of or relating to this
note shall be instituted only in a Federal or state court in Miami-Dade  County,
Florida,  (2) waive any  objection  which they may now or hereafter  have to the
laying of the venue of any such suit, action or proceeding,  and (3) irrevocably
submit to the jurisdiction of such Federal or state court in Miami-Dade  County,
Florida in any such  suit,  action or  proceeding,  but such  consent  shall not
constitute a general appearance or be available to any other person who is not a
party to this Note.  All parties hereto agree that the mailing of any process in
any suit,  action or proceeding in accordance with the notice provisions of this
Note shall constitute personal service thereof.

          (b) THE MAKER  HEREBY  WAIVES  ANY RIGHT TO TRIAL BY JURY IN ANY LEGAL
PROCEEDING RELATED IN ANY WAY TO THIS NOTE.

      10. NOTICES.  All notices or other communications required or permitted to
be given  pursuant to this Note shall be in writing and shall be  considered  as
duly given on (a) the date of delivery,  if delivered in person or by nationally
recognized  overnight  delivery service or (b) five days after mailing if mailed
by registered or certified mail,  return receipt requested to the party entitled
to receive the same,  if to the  Holder,  at his or its address on the books and
records of the Maker, and if to the Maker, to Genetic  Vectors,  Inc., 5201 N.W.
77th Avenue,  Suite 100, Miami, Florida 33166,  Attention:  Mead M. McCabe, Jr.,
with a copy to Kirkpatrick & Lockhart LLP, Miami Center - 20th Floor,  201 South
Biscayne Boulevard, Miami, Florida 33131, Attention: Clayton E. Parker, Esq. Any
party may change its address by giving notice to the other party stating its new


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address. Commencing on the tenth day after the giving of such notice, such newly
designated  address shall be such party's address for the purpose of all notices
or other communications required or permitted to be given pursuant to this Note.

      11. SEVERABILITY.  If any provision of  this Note shall be held invalid or
unenforceable,  such  invalidity or  unenforceability  shall attach only to such
provision and shall not in any manner affect or render invalid or  unenforceable
any other  severable  provision of this Note, and this Note shall be carried out
as if any such invalid or unenforceable provision were not contained herein. 

      12. AMENDMENT.  This Note shall not be  amended  without the prior written
consent of the Holder. 

                                      GENETIC VECTORS, INC.




                                      By:   ___________________________________
                                      Its:  ___________________________________
ATTEST:




By:   _____________________________
Its:  _____________________________

Corporate Seal:


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