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                                                                   Exhibit 10.70


                                 HYBRIDON, INC.

                 AMENDED AND RESTATED 1997 STOCK INCENTIVE PLAN

1.       Purpose

         The purpose of this Amended and Restated 1997 Stock Incentive Plan (the
"Plan") of Hybridon, Inc., a Delaware corporation (the "Company"), is to advance
the interests of the Company's stockholders by enhancing the Company's ability
to attract, retain and motivate persons who make (or are expected to make)
important contributions to the Company by providing such persons with equity
ownership opportunities and performance-based incentives and thereby better
aligning the interests of such persons with those of the Company's stockholders.
Except where the context otherwise requires, the term "Company" shall include
any present or future subsidiary corporations of the Company as defined in
Section 424(f) of the Internal Revenue Code of 1986, as amended, and any
regulations promulgated thereunder (the "Code") (a "Subsidiary").

2.       Eligibility

All of the Company's employees, officers, directors, consultants and advisors
are eligible to be granted options, restricted stock, or other stock-based
awards (each, an "Award") under the Plan. Any person who has been granted an
Award under the Plan shall be deemed a "Participant".

3.       Administration, Delegation

         (a) Administration by Board of Directors. The Plan will be administered
by the Board of Directors of the Company (the "Board"). The Board shall have
authority to grant Awards and to adopt, amend and repeal such administrative
rules, guidelines and practices relating to the Plan as it shall deem advisable
from time to time. The Board may correct any defect, supply any omission or
reconcile any inconsistency in the Plan or any Award in the manner and to the
extent it shall deem expedient to carry the Plan into effect and it shall be the
sole and final judge of such expediency. No member of the Board shall be liable
for any action or determination relating to the Plan. All decisions by the Board
shall be made in the Board's sole discretion and shall be final and binding on
all persons having or claiming any interest in the Plan or in any Award. No
director or person acting pursuant to the authority delegated by the Board shall
be liable for any action or determination under the Plan made in good faith.

         (b) Delegation to Executive Officers. To the extent permitted by
applicable law, the Board may delegate to one or more executive officers of the
Company the power to make Awards and exercise such other powers under the Plan
as the Board may determine, provided that the Board shall fix the maximum number
of shares subject to Awards and the maximum number of shares for any one
Participant to be made by such executive officers.


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         (c) Appointment of Committees. To the extent permitted by applicable
law, the Board may delegate any or all of its powers under the Plan to one or
more committees or subcommittees of the Board (a "Committee"). For so long as
the common stock, $.001 par value per share (the "Common Stock"), of the Company
is registered under the Securities Exchange Act of 1934 (the "Exchange Act"),
the Board shall appoint one such Committee of not less than two members, each
member of which shall be an "outside director" within the meaning of Section
162(m) of the Code and a "non-employee director" as defined in Rule 16b-3
promulgated under the Exchange Act." All references in the Plan to the "Board"
shall mean a Committee or the Board or the executive officer referred to in
Section 3(b) to the extent that the Board's powers or authority under the Plan
have been delegated to such Committee or executive officer.

4.       Stock Available for Awards

         (a) Number of Shares. Subject to adjustment under Section 4(c), Awards
may be made under the Plan for up to 13,500,000 shares of Common Stock. If any
Award expires or is terminated, surrendered or canceled without having been
fully exercised or is forfeited in whole or in part or results in any Common
Stock not being issued, the unused Common Stock covered by such Award shall
again be available for the grant of Awards under the Plan, subject, however, in
the case of Incentive Stock Options (as hereinafter defined), to any limitation
required under the Code. Shares issued under the Plan may consist in whole or in
part of authorized but unissued shares or treasury shares.

         (b) Per Participant Limit. Subject to adjustment under Section 4(c),
the maximum number of shares with respect to which an Award or Awards may be
granted to any Participant under the Plan shall be determined by dividing
1,500,000 by the fair market value of a share of the Company's common stock at
the time of grant provided that under no circumstances shall any Award to any
Participant exceed 5,000,000 per calendar year. The per Participant limit
described in this Section 4(b) shall be construed and applied consistently with
Section 162(m) of the Code and shall apply to the Company's "covered employees'
as that terms is defined in said Section 162(m).

         (c) Adjustment to Common Stock. In the event of any stock split, stock
dividend, recapitalization, reorganization, merger, consolidation, combination,
exchange of shares, liquidation, spin-off or other similar change in
capitalization or event, or any distribution to holders of Common Stock other
than a normal cash dividend, (i) the number and class of securities available
under this Plan, (ii) the number and class of security and exercise price per
share subject to each outstanding Option (as defined below), (iii) the
repurchase price per security subject to each outstanding Restricted Stock Award
(as defined below), and (iv) the terms of each other outstanding stock-based
Award shall be appropriately adjusted by the Company (or substituted Awards may
be made, if applicable) to the extent the Board shall determine, in good faith,
that such an adjustment (or substitution) is necessary and appropriate. If this
Section 4(c) applies and Section 8(e)(1) also applies to any event, Section
8(e)(1) shall be applicable to such event, and this Section 4(c) shall not be
applicable.

5.       Stock Options


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         (a) General. The Board may grant options to purchase Common Stock
(each, an "Option") and determine the number of shares of Common Stock to be
covered by each Option, the exercise price of each Option and the conditions and
limitations applicable to the exercise of each Option, including conditions
relating to applicable federal or state securities laws, as it considers
necessary or advisable. An Option which is not intended to be an Incentive Stock
Option shall be designated a "Nonstatutory Stock Option".

         (b) Incentive Stock Options. An Option that the Board intends to be an
"incentive stock option" as defined in Section 422 of the Code (an "Incentive
Stock Option") shall only be granted to employees of the Company and shall be
subject to and construed consistently with the requirements of Section 422 of
the Code. The Company shall have no liability to a Participant, or any other
party, if an Option (or any part thereof) which is intended to be an Incentive
Stock Option is not an Incentive Stock Option.

         (c) Exercise Price. The Board shall establish the exercise price at the
time each Option is granted and specify it in the applicable option agreement.

         (d) Duration of Options. Each Option shall be exercisable at such times
and subject to such terms and conditions as the Board may specify in the
applicable option agreement.

         (e) Exercise of Option. Options may be exercised only by delivery to
the Company of a written notice of exercise signed by the proper person together
with payment in full as specified in Section 5(f) for the number of shares for
which the Option is exercised.

         (f) Payment Upon Exercise. Common Stock purchased upon the exercise of
an Option granted under the Plan shall be paid for as follows:

                  (1) in cash or by check, payable to the order of the Company;

                  (2) except as the Board may otherwise provide in an Option
         Agreement, delivery of an irrevocable and unconditional undertaking by
         a creditworthy broker to deliver promptly to the Company sufficient
         funds to pay the exercise price, or delivery by the Participant to the
         Company of a copy of irrevocable and unconditional instructions to a
         creditworthy broker to deliver promptly to the Company cash or a check
         sufficient to pay the exercise price;

                  (3) to the extent permitted by the Board and explicitly
         provided in the Option Agreement (i) by delivery of shares of Common
         Stock owned by the Participant valued at their fair market value as
         determined by the Board in good faith ("Fair Market Value"), which
         Common Stock was owned by the Participant at least six months prior to
         such delivery, (ii) by delivery of a promissory note of the Participant
         to the Company on terms determined by the Board, or (iii) by payment of
         such other lawful consideration as the Board may determine; or


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                  (4) any combination of the above permitted forms of payment.

6.       Restricted Stock

         (a) Grants. The Board may grant Awards entitling recipients to acquire
shares of Common Stock, subject to the right of the Company to repurchase all or
part of such shares at their issue price or other stated or formula price (or to
require forfeiture of such shares if issued at no cost) from the recipient in
the event that conditions specified by the Board in the applicable Award are not
satisfied prior to the end of the applicable restriction period or periods
established by the Board for such Award (each, a "Restricted Stock Award").

         (b) Terms and Conditions. The Board shall determine the terms and
conditions of any such Restricted Stock Award, including the conditions for
repurchase (or forfeiture) and the issue price, if any. Any stock certificates
issued in respect of a Restricted Stock Award shall be registered in the name of
the Participant and, unless otherwise determined by the Board, deposited by the
Participant, together with a stock power endorsed in blank, with the Company (or
its designee). At the expiration of the applicable restriction periods, the
Company (or such designee) shall deliver the certificates no longer subject to
such restrictions to the Participant or if the Participant has died, to the
beneficiary designated, in a manner determined by the Board, by a Participant to
receive amounts due or exercise rights of the Participant in the event of the
Participant's death (the "Designated Beneficiary"). In the absence of an
effective designation by a Participant, Designated Beneficiary shall mean the
Participant's estate.

7.       Other Stock-Based Awards

         The Board shall have the right to grant other Awards based upon the
Common Stock having such terms and conditions as the Board may determine,
including the grant of shares based upon certain conditions, the grant of
securities convertible into Common Stock and the grant of stock appreciation
rights.

8.       General Provisions Applicable to Awards

         (a) Transferability of Awards. Except as the Board may otherwise
determine or provide in an Award, Awards shall not be sold, assigned,
transferred, pledged or otherwise encumbered by the person to whom they are
granted, either voluntarily or by operation of law, except by will or the laws
of descent and distribution, and, during the life of the Participant, shall be
exercisable only by the Participant. References to a Participant, to the extent
relevant in the context, shall include references to authorized transferees.

         (b) Documentation. Each Award under the Plan shall be evidenced by a
written instrument in such form as the Board shall determine. Each Award may
contain terms and conditions in addition to those set forth in the Plan.

         (c) Board Discretion. Except as otherwise provided by the Plan, each
type of Award may be made alone or in addition or in relation to any other type
of Award. The terms


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of each type of Award need not be identical, and the Board need not treat
Participants uniformly.

         (d) Termination of Status. The Board shall determine the effect on an
Award of the disability, death, retirement, authorized leave of absence or other
change in the employment or other status of a Participant and the extent to
which, and the period during which, the Participant, the Participant's legal
representative, conservator, guardian or Designated Beneficiary may exercise
rights under the Award.

         (e)      Acquisition Events

                  (1) Consequences of Acquisition Events. Except to the extent
         otherwise provided in the instrument evidencing the Award or in any
         other agreement between the Participant and the Company:

                           (A) Upon the occurrence of an Acquisition Event,

                  (i) all Restricted Stock Awards then outstanding shall become
         immediately free of all restrictions; and

                  (ii) all other stock-based Awards other than Options and stock
         appreciation rights shall become immediately exercisable, realizable or
         vested in full, or shall be immediately free of all restrictions or
         conditions, as the case may be.

                           (B) Upon the execution by the Company of an agreement
                  to effect an Acquisition Event other than a Change of Control
                  Event, all Options and stock appreciation rights then
                  outstanding shall become immediately exercisable in full upon
                  the occurrence of the Acquisition Event or such earlier date
                  as may be specified by the Board by written notice to the
                  Participants, and the Board may take one or both of the
                  following actions with respect to then outstanding Options and
                  stock appreciation rights: (I) provide that such Options and
                  stock appreciation rights shall be assumed, or equivalent
                  Options or stock appreciation rights be substituted by the
                  acquiring or succeeding corporation (or an affiliate thereof),
                  or (II) upon written notice to the Participants, provide that
                  all then unexercised Options and stock appreciation rights
                  will terminate to the extent not exercised by the Participants
                  prior to the consummation of such Acquisition Event or such
                  earlier date as may be specified by the Board by written
                  notice to Participants.

                           (C) Upon the occurrence of a Change of Control Event,
                  all Options and stock appreciation rights then outstanding
                  shall become immediately exercisable in full.

         An "Acquisition Event" shall mean: (a) any merger or consolidation
which results in the voting securities of the Company outstanding immediately
prior thereto representing (either by remaining outstanding or by being
converted into voting securities of the surviving or acquiring entity) less than
60% of the combined voting power of the voting securities of the Company or such
surviving or acquiring entity outstanding immediately after such merger or
consolidation; (b) any sale of all or substantially all of the assets of the
Company; (c) the


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complete liquidation of the Company; or (d) the acquisition of "beneficial
ownership" (as defined in Rule 13d-3 under the Exchange Act) of securities of
the Company representing 50% or more of the combined voting power of the
Company's then outstanding securities (other than through a merger or
consolidation or an acquisition of securities directly from the Company) by any
"person," as such term is used in Sections 13(d) and 14(d) of the Exchange Act,
other than the Company, any trustee or other fiduciary holding securities under
an employee benefit plan of the Company or any corporation owned directly or
indirectly by the stockholders of the Company in substantially the same
proportion as their ownership of stock of the Company (an event specified in
this clause (d) being referred to as a "Change of Control Event").

                  (2) Assumption of Options Upon Certain Events. The Board may
         grant Awards under the Plan in substitution for stock and stock-based
         awards held by employees of another corporation who become employees of
         the Company as a result of a merger or consolidation of the employing
         corporation with the Company or the acquisition by the Company of
         property or stock of the employing corporation. The substitute Awards
         shall be granted on such terms and conditions as the Board considers
         appropriate in the circumstances.

         (f) Withholding. Each Participant shall pay to the Company, or make
provision satisfactory to the Board for payment of, any taxes required by law to
be withheld in connection with Awards to such Participant no later than the date
of the event creating the tax liability. The Board may allow Participants to
satisfy such tax obligations in whole or in part in shares of Common Stock,
including shares retained from the Award creating the tax obligation, valued at
their Fair Market Value. The Company may, to the extent permitted by law, deduct
any such tax obligations from any payment of any kind otherwise due to a
Participant.

         (g) Amendment of Award. The Board may amend, modify or terminate any
outstanding Award, including but not limited to, substituting therefor another
Award of the same or a different type, changing the date of exercise or
realization, and converting an Incentive Stock Option to a Nonstatutory Stock
Option, provided that the Participant's consent to such action shall be required
unless the Board determines that the action, taking into account any related
action, would not materially and adversely affect the Participant.

         (h) Conditions on Delivery of Stock. The Company will not be obligated
to deliver any shares of Common Stock pursuant to the Plan or to remove
restrictions from shares previously delivered under the Plan until (i) all
conditions of the Award have been met or removed to the satisfaction of the
Company, (ii) in the opinion of the Company's counsel, all other legal matters
in connection with the issuance and delivery of such shares have been satisfied,
including any applicable securities laws and any applicable stock exchange or
stock market rules and regulations, and (iii) the Participant has executed and
delivered to the Company such representations or agreements as the Company may
consider appropriate to satisfy the requirements of any applicable laws, rules
or regulations.

         (i) Acceleration. The Board may at any time provide that any Options
shall become immediately exercisable in full or in part, that any Restricted
Stock Awards shall be


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free of all restrictions or that any other stock-based Awards may become
exercisable in full or in part or free of some or all restrictions or
conditions, or otherwise realizable in full or in part, as the case may be.

9.       Miscellaneous

         (a) No Right To Employment or Other Status. No person shall have any
claim or right to be granted an Award, and the grant of an Award shall not be
construed as giving a Participant the right to continued employment or any other
relationship with the Company. The Company expressly reserves the right at any
time to dismiss or otherwise terminate its relationship with a Participant free
from any liability or claim under the Plan, except as expressly provided in the
applicable Award.

         (b) No Rights As Stockholder. Subject to the provisions of the
applicable Award, no Participant or Designated Beneficiary shall have any rights
as a stockholder with respect to any shares of Common Stock to be distributed
with respect to an Award until becoming the record holder of such shares.

         (c) Effective Date and Term of Plan. The Plan shall become effective on
the date on which it is adopted by the Board, but no Award granted to a
Participant designated as subject to Section 162(m) by the Board shall become
exercisable, vested or realizable, as applicable to such Award, unless and until
the Plan has been approved by the Company's stockholders. No Awards shall be
granted under the Plan after the completion of ten years from the earlier of (i)
the date on which the Plan was adopted by the Board or (ii) the date the Plan
was approved by the Company's stockholders, but Awards previously granted may
extend beyond that date.

         (d) Amendment of Plan. The Board may amend, suspend or terminate the
Plan or any portion thereof at any time, provided that no Award granted to a
Participant designated as subject to 162(m) by the Board after the date of such
amendment shall become exercisable, realizable or vested, as applicable to such
Award (to the extent that such amendment to the Plan was required to grant such
Award to a particular Participant), unless and until such amendment shall have
been approved by the Company's stockholders.

         (e) Stockholder Approval. For purposes of this Plan, stockholder
approval shall mean approval by a vote of the stockholders in accordance with
the requirements of Section 162(m) of the Code.

         (f) Governing Law. The provisions of the Plan and all Awards made
hereunder shall be governed by and interpreted in accordance with the laws of
the State of Delaware, without regard to any applicable conflicts of law.


                             Adopted by the Compensation Committee of the
                             Board of Directors on March 28, 2001.


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                             Approved by the stockholders of the
                             Company on ____________________.


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