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                                                                   Exhibit 10.51

                           BOSTON LIFE SCIENCES, INC.

                       NONSTATUTORY STOCK OPTION AGREEMENT
                     GRANTED UNDER 2005 STOCK INCENTIVE PLAN

1.    Grant of Option.

      This agreement evidences the grant by Boston Life Sciences, Inc., a
Delaware corporation (the "Company"), on January 6, 2006 (the "Grant Date") to
Peter G. Savas, a director and executive officer of the Company (the
"Participant"), of an option to purchase, in whole or in part, on the terms
provided herein and in the Company's 2005 Stock Incentive Plan (the "Plan"), a
total of 350,000 shares (the "Shares") of common stock, $0.01 par value per
share, of the Company ("Common Stock") at $2.50 per Share. Unless earlier
terminated, this option shall expire at 5:00 p.m., Eastern time, on January 5,
2016 (the "Final Exercise Date").

      It is intended that the option evidenced by this agreement shall not be an
incentive stock option as defined in Section 422 of the Internal Revenue Code of
1986, as amended, and any regulations promulgated thereunder (the "Code").
Except as otherwise indicated by the context, the term "Participant", as used in
this option, shall be deemed to include any person who acquires the right to
exercise this option validly under its terms.

2.    Vesting Schedule.

      This option will become exercisable ("vest") in 96 equal monthly
installments, provided that the Participant remains an executive officer of the
Company. Additionally, these options are subject to acceleration upon
achievement of the following product development milestones: (i) one-third of
the outstanding portion of the foregoing options will accelerate and vest upon
completion of the Company's POET-1 clinical trial for ALTROPANE; (ii) one-third
of the outstanding portion of the foregoing options will accelerate and vest
upon the earlier of the Company's submission of a New Drug Application for
ALTROPANE with the Food and Drug Administration ("FDA") or the initiation of the
Company's POET-2 clinical trial for ALTROPANE; and (iii) one-third of the
outstanding portion of the foregoing options will immediately accelerate and
vest upon the earlier of the successful achievement of a partnership arrangement
with respect to ALTROPANE or the FDA's approval of a New Drug Application for
ALTROPANE.

      The right of exercise shall be cumulative so that to the extent the option
is not exercised in any period to the maximum extent permissible it shall
continue to be exercisable, in whole or in part, with respect to all Shares for
which it is vested until the earlier of the Final Exercise Date or the
termination of this option under Section 3 hereof or the Plan.

3.    Exercise of Option.

      (a) Form of Exercise. Each election to exercise this option shall be by
written notice in the form attached hereto as Exhibit A, signed by the
Participant, and received by the Company at its principal office, accompanied by
this agreement, and payment in full in the manner

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provided in the Plan. The Participant may purchase less than the number of
shares covered hereby, provided that no partial exercise of this option may be
for any fractional share.

      (b) Continuous Relationship with the Company Required. Except as otherwise
provided in this Section 3, this option may not be exercised unless the
Participant, at the time he or she exercises this option, is, and has been at
all times since the Grant Date, an employee, officer or director of, or
consultant or advisor to, the Company or any other entity the employees,
officers, directors, consultants, or advisors of which are eligible to receive
option grants under the Plan (an "Eligible Participant").

      (c) Termination of Relationship with the Company. If the Participant
ceases to be an Eligible Participant for any reason, then, except as provided in
paragraphs (d) and (e) below, the right to exercise this option shall terminate
three months after such cessation (but in no event after the Final Exercise
Date), provided that this option shall be exercisable only to the extent that
the Participant was entitled to exercise this option on the date of such
cessation. Notwithstanding the foregoing, if the Participant, prior to the Final
Exercise Date, violates the non-competition or confidentiality provisions of any
employment contract, confidentiality and nondisclosure agreement or other
agreement between the Participant and the Company, the right to exercise this
option shall terminate immediately upon written notice to the Participant from
the Company describing such violation.

      (d) Exercise Period Upon Death or Disability. If the Participant dies or
becomes disabled (within the meaning of Section 22(e)(3) of the Code) prior to
the Final Exercise Date while he or she is an Eligible Participant and the
Company has not terminated such relationship for "cause" as specified in
paragraph (e) below, this option shall be exercisable, within the period of one
year following the date of death or disability of the Participant, by the
Participant (or in the case of death by an authorized transferee), provided that
this option shall be exercisable only to the extent that this option was
exercisable by the Participant on the date of his or her death or disability,
and further provided that this option shall not be exercisable after the Final
Exercise Date.

      (e) Discharge for Cause. If the Participant, prior to the Final Exercise
Date, is discharged by the Company for "cause" (as defined below), the right to
exercise this option shall terminate immediately upon the effective date of such
discharge. "Cause" shall mean willful misconduct by the Participant or willful
failure by the Participant to perform his or her responsibilities to the Company
(including, without limitation, breach by the Participant of any provision of
any employment, consulting, advisory, nondisclosure, non-competition or other
similar agreement between the Participant and the Company), as determined by the
Company, which determination shall be conclusive. The Participant shall be
considered to have been discharged for "Cause" if the Company determines, within
30 days after the Participant's resignation, that discharge for cause was
warranted.

4.    Withholding.

      No Shares will be issued pursuant to the exercise of this option unless
and until the Participant pays to the Company, or makes provision satisfactory
to the Company for payment

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of, any federal, state or local withholding taxes required by law to be withheld
in respect of this option.

5.    Nontransferability of Option.

      This option may not be sold, assigned, transferred, pledged or otherwise
encumbered by the Participant, either voluntarily or by operation of law, except
by will or the laws of descent and distribution, and, during the lifetime of the
Participant, this option shall be exercisable only by the Participant.

6.    Provisions of the Plan.

      This option is subject to the provisions of the Plan, a copy of which is
furnished to the Participant with this option.

      IN WITNESS WHEREOF, the Company has caused this option to be executed
under its corporate seal by its duly authorized officer. This option shall take
effect as a sealed instrument.

                            BOSTON LIFE SCIENCES, INC.

Dated: January 6, 2006      By: /s/ Kenneth L. Rice, Jr.
                                ------------------------
                                  Name: Kenneth L. Rice, Jr.
                                  Title: Executive Vice President Finance and
                                         Administration and CFO

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                            PARTICIPANT'S ACCEPTANCE

      The undersigned hereby accepts the foregoing option and agrees to the
terms and conditions thereof. The undersigned hereby acknowledges receipt of a
copy of the Company's 2005 Stock Incentive Plan.

                                           PARTICIPANT: /s/ Peter G. Savas
                                                        ------------------

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                                    EXHIBIT A

                         NOTICE OF STOCK OPTION EXERCISE

                                                        Date: __________________

Participant name and address:

__________________________
__________________________
__________________________

Attention: Treasurer

Dear Sir or Madam:

      I am the holder of an Nonstatutory Stock Option granted to me under the
Boston Life Sciences, Inc. (the "Company") 2005 Stock Incentive Plan on
__________ for the purchase of __________ shares of Common Stock of the Company
at a purchase price of $__________ per share.

      I hereby exercise my option to purchase _________ shares of Common Stock
(the "Shares"), for which I have enclosed __________ in the amount of $________.
Please register my stock certificate as follows:

                                                (check applicable box)

      Name(s):    _______________________       (theeta)  TEN COM

                  _______________________       (theeta)  TEN ENT

      Address:    _______________________       (theeta)  JT TEN

      Tax I.D. #: _______________________       (theeta)  UNIF GIFT MIN ACT

      I represent, warrant and covenant as follows:

1. I am purchasing the Shares for my own account for investment only, and not
with a view to, or for sale in connection with, any distribution of the Shares
in violation of the Securities Act of 1933 (the "Securities Act"), or any rule
or regulation under the Securities Act.

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2. I have had such opportunity as I have deemed adequate to obtain from
representatives of the Company such information as is necessary to permit me to
evaluate the merits and risks of my investment in the Company.

3. I have sufficient experience in business, financial and investment matters to
be able to evaluate the risks involved in the purchase of the Shares and to make
an informed investment decision with respect to such purchase.

4. I can afford a complete loss of the value of the Shares and am able to bear
the economic risk of holding such Shares for an indefinite period.

5. I understand that (i) the Shares have not been registered under the
Securities Act and are "restricted securities" within the meaning of Rule 144
under the Securities Act, (ii) the Shares cannot be sold, transferred or
otherwise disposed of unless they are subsequently registered under the
Securities Act or an exemption from registration is then available; (iii) in any
event, the exemption from registration under Rule 144 will not be available for
at least one year and even then will not be available unless a public market
then exists for the Common Stock, adequate information concerning the Company is
then available to the public, and other terms and conditions of Rule 144 are
complied with; and (iv) there is now no registration statement on file with the
Securities and Exchange Commission with respect to any stock of the Company and
the Company has no obligation or current intention to register the Shares under
the Securities Act.

Very truly yours,

_______________________
(Signature)

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