<PAGE>


                                                                    EXHIBIT 10.2


                                 PROMISSORY NOTE

$4.0 MILLION                                                    OCTOBER 26, 2006

         FOR VALUE RECEIVED, Boston Life Sciences, Inc., a Delaware corporation
("MAKER"), hereby unconditionally promises to pay to the order of Thomas Gipson
("LENDER"), in lawful money of the United States of America and in immediately
available funds, the principal sum of Four Million Dollars ($4,000,000), or, if
less, the aggregate unpaid principal amount of all Advances (defined in Section
1 below) (the "LOAN"), together with accrued and unpaid interest thereon, each
due and payable on the dates and in the manner set forth below.

         1.       ADVANCES. From time to time prior to the Maturity Date
(defined in Section 2 below), and so long as no Event of Default exists, the
Lender shall make advances (the "Advances") to the Maker, and the Maker may
borrow funds from the Lender hereunder, provided that the aggregate principal
amount of all Advances shall in no event exceed $4,000,000. Each request for an
Advance shall be made by the Maker in writing, delivered to the Lender at least
seven (7) business days prior the requested date of such Advance and shall
specify the date of such Advance, and the amount of such Advance. Each Advance
shall be in the minimum amount of $1,000,000. The Lender shall, and is hereby
authorized to, record on the schedule attached hereto, or to otherwise record in
accordance with its usual practice, the date and amount of each Advance and the
date and amount of each principal payment hereunder, provided, however, that any
failure to so record any Advance or Payment shall not in any manner affect the
obligation of the Maker to repay any Advance in accordance with the terms
hereof.

         2.       PRINCIPAL REPAYMENT. The outstanding principal amount of the
Loan shall be due and payable on the earliest to occur of (i) June 30, 2007,
(ii) the date on which the Maker consummates an equity financing in which the
aggregate gross proceeds to the Maker total at least $10,000,000 and (iii) the
date on which the Lender declares an Event of Default (as defined in Section 8
below) to have occurred (the first of the events set forth in Section 2(i),
2(ii) and 2(iii) to occur being referred to herein as the "Maturity Date"). This
Note may be prepaid in whole or in part at any time without premium or penalty.

         3.       INTEREST RATE AND PAYMENTS. Interest shall accrue on each
Advance from the date of such Advance and all unpaid interest shall be due and
payable on the Maturity Date. The Maker promises to pay interest on the
outstanding principal amount of each Advance from the date of such Advance until
payment in full of such Advance at a per annum interest rate equal to (i) nine
percent (9%) from the date hereof to the Maturity Date, (ii) from and after the
Maturity Date, or during the continuance of an Event of Default (as defined
below), at the rate set forth in clause (i) plus two percent (2%), or (iii) if
less than the rates applicable under both clauses (i) and (ii), the maximum rate
permissible by law. Interest shall be calculated on the basis of a 360-day year
for the actual number of days elapsed.

         4.       PLACE OF PAYMENT. All amounts payable hereunder shall be
payable in immediately available funds at the office of the Lender, c/o Ingalls
& Snyder, 61 Broadway, New York, NY, unless another place of payment shall be
specified in writing by the Lender.


                                                                 Promissory Note

<PAGE>

         5.       APPLICATION OF PAYMENTS. Payment on this Note shall be applied
first to costs and expenses due hereunder, if any, then to accrued interest, and
thereafter to the outstanding principal balance hereof. Any principal repayment
or interest payment hereunder not paid when due, whether at stated maturity, by
acceleration or otherwise, shall bear interest at the rate set forth in clause
(ii) of Section 2 hereof (or, if such rate exceeds the maximum rate permitted by
law, then at such maximum rate permitted by law) until paid in full.

         6.       REPRESENTATIONS AND WARRANTIES. The Maker represents and
warrants to the Lender that:

                  (a)      the Maker is duly organized, validly existing, and in
                           good standing under the laws of its jurisdiction of
                           incorporation and is duly qualified and in good
                           standing in every other jurisdiction where the nature
                           of its business or the location or ownership of its
                           properties requires such qualification and where the
                           failure to be so qualified would reasonably be
                           expected to have a material adverse effect on the
                           Maker's business, operations, properties, assets or
                           condition (financial or otherwise);

                  (b)      the Maker has the full corporate power and authority
                           to execute and deliver this Note and to perform all
                           of the obligations hereunder, and all necessary
                           corporate action has been taken to execute and
                           deliver this Note and to make the borrowings
                           hereunder;

                  (c)      this Note constitutes the legal, valid, and binding
                           obligations of the Maker, enforceable against the
                           Maker in accordance with its terms, subject to
                           applicable bankruptcy, insolvency, reorganization or
                           similar laws generally affecting the enforcement of
                           the rights of creditors; and

                  (d)      the execution, delivery and performance by the Maker
                           of this Note does not (i) violate any provisions of
                           the Maker's Certificate of Incorporation, as amended,
                           bylaws, as amended, or any contract, agreement, law,
                           regulation, order, decree or writ to which the Maker
                           or any of its properties are subject or (ii) require
                           the consent or approval of any person, entity or
                           authority, including, without limitation, any
                           regulatory authority or governmental body of the
                           United States of America or any state thereof or any
                           political subdivision of any of the foregoing.

         7.       NEGATIVE COVENANTS. So long as any principal and interest
remains outstanding under this Note, the Maker shall not:

                  (a)      create, incur, assume, guaranty, become liable with
                           respect to (contingently or otherwise), or permit to
                           be outstanding any indebtedness for money borrowed
                           (including, without limitation, any indebtedness
                           evidenced by any notes, instruments or agreements or
                           in connection with any capitalized lease), except for
                           the obligations under this Note or a promissory note
                           of even date herewith pursuant to which the Maker
                           shall be permitted to

                                                                 Promissory Note

                                      -2-
<PAGE>

                           borrow up to an additional principal sum of
                           $4,000,000 together with interest thereon;

                  (b)      (i) declare or pay any cash dividend, or make a
                           distribution on, repurchase, or redeem, any class of
                           stock of the Maker, other than pursuant to repurchase
                           obligations under existing employee stock purchase or
                           option plans or (ii) sell, lease, transfer or
                           otherwise dispose of any material assets or property
                           of the Maker; or

                  (c)      dissolve or liquidate.

         8.       DEFAULT. Each of the following events shall be an "EVENT OF
DEFAULT" hereunder:

                  (a)      the Maker fails to pay any of the principal, interest
                           or any other amounts payable under this Note when and
                           as the same becomes due and payable;

                  (b)      the Maker files any petition or action for relief
                           under any bankruptcy, reorganization, insolvency or
                           moratorium law or any other law for the relief of, or
                           relating to, Maker, now or hereafter in effect, or
                           seeks the appointment of a custodian, receiver,
                           trustee (or other similar official) of the Maker or
                           all or any substantial portion of the Maker's assets,
                           or makes any assignment for the benefit of creditors
                           or takes any action in furtherance of any of the
                           foregoing, or fails to generally pay its debts as
                           they become due;

                  (c)      an involuntary petition is filed, or any proceeding
                           or case is commenced, against the Maker (unless such
                           proceeding or case is dismissed or discharged within
                           ninety (90) days of the filing or commencement
                           thereof) under any bankruptcy, reorganization,
                           arrangement, insolvency, adjustment of debt,
                           liquidation or moratorium statute now or hereafter in
                           effect, or a custodian, receiver, trustee, assignee
                           for the benefit of creditors (or other similar
                           official) is applied for, appointed for the Maker or
                           to take possession, custody or control of any
                           property of the Maker, or an order for relief is
                           entered against the Maker in any of the foregoing; or

                  (d)      any representation or warranty made or deemed made by
                           the Maker under this Note shall have been false or
                           misleading in any material respect when made or
                           deemed made.

         9.       REMEDIES. Upon the occurrence and during the continuance of an
Event of Default hereunder:

                  (a)      all unpaid principal, accrued interest and other
                           amounts owing hereunder shall, at the option of the
                           Lender, and, in the case of an Event of Default
                           pursuant to Section 8(b) or (c) above, automatically,
                           be immediately due, payable and collectible by the
                           Lender pursuant to applicable law;

                                                                 Promissory Note

                                      -3-
<PAGE>

                  (b)      any and all unpaid principal, interest or other
                           amounts due under this Note shall thereafter bear
                           interest at the maximum rate set forth in Section 3
                           hereof;

                  (c)      any and all of the Lender's obligations to make any
                           additional loans or advances hereunder shall
                           automatically terminate and expire; and

                  (d)      the Lender may exercise any and all rights and
                           remedies it may have under this Note or under
                           applicable law.

         All rights and remedies shall be cumulative and not exclusive. The
failure of the holder hereof to exercise all or any of its rights, remedies,
powers or privileges hereunder or applicable law, in any instance shall not
constitute a waiver thereof in that or any other instance.

         10.      EXPENSES. The Maker agrees to and shall pay to the Lender on
demand, any and all expenses, including, without limitation, reasonable
attorney's fees and disbursements, incurred or paid by the Lender in connection
herewith, including, without limitation, such fees, costs and expenses incurred
for collection or enforcement of amounts outstanding hereunder, for protecting,
preserving or enforcing the Lender's rights or remedies (including fees, costs
and expenses relating to any proceedings with respect to the bankruptcy,
reorganization, insolvency, readjustment of debt, dissolution or liquidation of
the Maker).

         11.      WAIVER. The Maker, for itself and its legal representatives,
successors and assigns, hereby expressly waives demand, protest, presentment,
notice of dishonor, notice of acceptance, and notice of protest, and all other
demands and notices in connection with the delivery, acceptance, performance,
default or enforcement of this Note and agrees that any extension, renewal or
postponement of the time of payment or any other indulgence to, or release of
any person now or hereafter obligated for the payment of this Note shall not
affect the Maker's liability hereunder.

         12.      NO RELIANCE. Lender hereby acknowledges (i) that Wilmer Cutler
Pickering Hale and Dorr LLP has served as counsel solely to the Maker in
connection with entering into this note, the Loan and the transactions
contemplated hereby, and (ii) that Lender (a) has sought the advice of his own
legal counsel and has not relied upon Wilmer Cutler Pickering Hale and Dorr LLP,
(b) has had an opportunity to fully discuss and review the terms of this note
with Lender's counsel, (c) understands the contents herein and freely and
voluntarily assents to all of the terms and conditions hereof and the
transactions contemplated hereby

         13.      GOVERNING LAW; CONSENT TO JURISDICTION. THIS NOTE IS INTENDED
TO TAKE EFFECT AS A SEALED INSTRUMENT AND SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS (AND NOT THE LAWS OF CONFLICT) OF THE COMMONWEALTH OF
MASSACHUSETTS. THE MAKER HEREBY IRREVOCABLY SUBMITS TO THE JURISDICTION OF THE
COURTS OF THE COMMONWEALTH OF MASSACHUSETTS AND THE UNITED STATES DISTRICT COURT
FOR THE COMMONWEALTH OF MASSACHUSETTS FOR THE PURPOSE OF ANY SUIT, ACTION OR
OTHER PROCEEDING ARISING OUT OF OR

                                                                 Promissory Note

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<PAGE>

RELATING TO THIS NOTE AND THE MAKER HEREBY IRREVOCABLY AGREES THAT ALL CLAIMS IN
RESPECT OF SUCH ACTION OR PROCEEDING MAY BE HEARD AND DETERMINED IN ANY SUCH
COURT AND IRREVOCABLY WAIVES ANY OBJECTION IT MAY NOW OR HEREAFTER HAVE AS TO
THE VENUE OF ANY SUCH SUIT, ACTION OR PROCEEDING BROUGHT IN ANY SUCH COURT OR
THAT SUCH COURT IS AN INCONVENIENT FORUM. NOTHING HEREIN SHALL LIMIT THE RIGHT
OF THE LENDER TO BRING PROCEEDINGS AGAINST THE MAKER IN THE COURTS OF ANY OTHER
JURISDICTION. ANY JUDICIAL PROCEEDING BY THE MAKER AGAINST THE LENDER OR ANY
AFFILIATE OF THE LENDER INVOLVING, DIRECTLY OR INDIRECTLY, ANY MATTER IN ANY WAY
ARISING OUT OF, RELATED TO, OR CONNECTED WITH THIS NOTE SHALL BE BROUGHT ONLY IN
A COURT IN THE COMMONWEALTH OF MASSACHUSETTS.

         14.      SUCCESSORS AND ASSIGNS. This Note and all obligations of the
Maker hereunder shall be binding upon the successors and assigns of the Maker,
and shall, together with the rights and remedies of the Lender hereunder, inure
to the benefit of the Lender, any future holder of this Note and their
respective successors and assigns, provided, however, the Maker may not transfer
or assign its rights or obligations hereunder without the express written
consent of the Lender, and any purported transfer or assignment by the Maker
without the Lender's written consent shall be null and void. The Lender may
assign, transfer, participate or endorse its rights under this Note without the
consent or approval of the Maker, and all such rights shall inure to the
Lender's successors and assigns. No sales of participations, other sales,
assignments, transfers, endorsements or other dispositions of any rights
hereunder or any portion thereof or interest therein shall in any manner affect
the obligations of the Maker under this Note. Upon request, the Maker shall, at
its own expense, execute and deliver to the assignee of this Note, a replacement
Note of equal and like tenor in an amount assigned to and assumed by such
assignee.

         15.      WAIVER OF JURY TRIAL AND CERTAIN DAMAGES. THE MAKER AND THE
LENDER EACH WAIVES ITS RIGHT TO A JURY TRIAL WITH RESPECT TO ANY ACTION OR CLAIM
ARISING OUT OF ANY DISPUTE IN CONNECTION WITH THIS NOTE, ANY RIGHTS OR
OBLIGATIONS HEREUNDER OR THE PERFORMANCE OF ANY SUCH RIGHTS OR OBLIGATIONS.
Except as prohibited by law, the Maker waives any right which it may have to
claim or recover in any litigation referred to in the preceding sentence any
special, exemplary, punitive or consequential damages or any damages other than,
or in addition to, actual damages. The Maker (i) certifies that neither the
Lender nor any representative, agent or attorney of the Lender has represented,
expressly or otherwise, that the Lender would not, in the event of litigation,
seek to enforce the foregoing waivers and (ii) acknowledges that, in entering
into the Note, the Lender is relying upon, among other things, the foregoing
waivers and certifications.

                                                                 Promissory Note

                                      -5-
<PAGE>

         16.      ENTIRE AGREEMENT; AMENDMENTS; INVALIDITY. This Note
constitutes the entire agreement and understanding of the parties, and
supercedes and replaces in their entirety any prior discussions, agreements,
etc., all of which are merged herein and therein. None of the terms of this Note
may be amended or otherwise modified except by an instrument executed by each of
the Maker and the Lender. If any term of this Note shall be held to be invalid,
illegal or unenforceable, the validity of all other terms hereof shall in no way
be affected thereby, and this Note shall be construed and be enforceable as if
such invalid, illegal or unenforceable term had not been included herein.

                                      *****

         IN WITNESS WHEREOF, this Note has been duly executed as an instrument
under seal as of the date first set forth above.



LENDER:                                 BOSTON LIFE SCIENCES, INC.


                                        By: /s/ Kenneth L. Rice, Jr.
                                            ------------------------------------

                                        Printed Name: Kenneth L. Rice, Jr.
                                                      --------------------------

                                        Title: EVP & CFO
                                               ---------------------------------

                                        Address:

                                        ----------------------------------------

                                        ----------------------------------------

                                        ----------------------------------------

ATTEST:

By: /s/ Thomas Gipson
   -----------------------------------

Title:
       -------------------------------




                                                                 Promissory Note

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<PAGE>


                   SCHEDULE OF LOAN AND PAYMENTS OF PRINCIPAL
                               TO PROMISSORY NOTE
                             OF BOSTON LIFE SCIENCES



<Table>
<Caption>
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Principal                               Principal
Amount of            Date               Amount               Unpaid
Advance                                 Paid                 Balance
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<S>                  <C>                <C>                  <C>

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</Table>

                                                                 Promissory Note


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