Document:

<PAGE>
                                                                    Exhibit 10.8

                                 HYBRIDON, INC.

                          REGISTRATION RIGHTS AGREEMENT

                            dated as of May 20, 2005
<PAGE>
                                 HYBRIDON, INC.

                          REGISTRATION RIGHTS AGREEMENT

     This Registration Rights Agreement (this "AGREEMENT") is entered into as of
May 20, 2005 by and among Hybridon, Inc., a Delaware corporation (the
"COMPANY"), the persons and entities listed on the Schedule of Purchasers
attached hereto as Exhibit A (the "PURCHASERS") and the entity listed on the
Agent Schedule attached hereto as Exhibit B (the "AGENT"). The Purchasers and
the Agent shall become parties to this Agreement by the execution and delivery
of counterpart signature pages hereto in a form reasonably satisfactory to the
Company.

     WHEREAS, the Company is conducting an offering (the "OFFERING") of
convertible subordinated notes (the "NOTES"), as described in the Confidential
Private Placement Memorandum dated April 26, 2005 (the "MEMORANDUM");

     WHEREAS, either the Company or the Purchasers may, under specified
circumstances, cause the Notes to be converted into shares of the Company's
common stock, $0.001 par value per share (the "COMMON STOCK"), as described in
the Memorandum;

     WHEREAS, the Company may pay accrued interest on the Notes by issuing to
the Purchasers shares of Common Stock under the terms of the Notes (the
"INTEREST SHARES");

     WHEREAS, in connection with the Offering, the Company has engaged the Agent
and has agreed to issue to the Agent a warrant (the "AGENT WARRANT") to purchase
shares of Common Stock; and

     WHEREAS, to induce the Purchasers to purchase Notes in the Offering and the
Agent to assist the Company in the Offering, the Company has agreed to provide
certain registration rights under the Securities Act (as defined below) and
applicable state securities laws;

     NOW, THEREFORE, in consideration of the promises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company, the Agent and each of
the Purchasers hereby agree as follows:

     1. Certain Definitions. As used in this Agreement, the following terms
shall have the following meanings:

          (a) "Business Day" means any day other than Saturday, Sunday or any
other day on which commercial banks in The City of New York or in Boston,
Massachusetts are required by law to remain closed.

          (b) "Commission" means the Securities and Exchange Commission, or any
other federal agency at the time administering the Securities Act.

          (c) "Exchange Act" means the Securities Exchange Act of 1934, as
amended, or any successor federal statute, and the rules and regulations of the
Commission issued under such Act, as they each may, from time to time, be in
effect.

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          (d) "Indemnified Party" means a party entitled to indemnification
pursuant to Section 7.

          (e) "Indemnifying Party" means a party obligated to provide
indemnification pursuant to Section 7.

          (f) "Person" means an individual, a limited liability company, a
partnership, a joint venture, a corporation, a trust, an unincorporated
organization or association and governmental or any department or agency
thereof.

          (g) "Registrable Securities" means (i) the shares of Common Stock
issuable upon conversion of the Notes, (ii) the shares of Common Stock issued or
issuable upon exercise of the Agent Warrant, (iii) solely in the context of an
Interest Payment Registration Statement, the Interest Shares, and (iv) any other
shares of Common Stock issued in respect of such shares (as a result of a stock
split, stock dividend, reclassification, recapitalization or other similar
transaction affecting the Common Stock); provided, however, that shares of
Common Stock that are Registrable Securities shall cease to be Registrable
Securities upon the earliest of (A) the date that such shares are eligible to be
sold under Rule 144 of the Securities Act, without restriction by the volume
limitations of Rule 144(e) of the Securities Act, (B) the date that such shares
are sold (I) pursuant to a registration statement, (II) to or through a broker,
dealer or underwriter in a public securities transaction and/or (III) in a
transaction exempt from the registration and prospectus delivery requirements of
the Securities Act such that all transfer restrictions and restrictive legends
with respect thereto, if any, are removed upon the consummation of such sale, or
(C) any sale or transfer to any Person which by virtue of Section 9 of this
Agreement is not entitled to the rights provided by this Agreement. Wherever
reference is made in this Agreement to a request or consent of holders of a
certain percentage of Registrable Securities, the determination of such
percentage shall include shares of Common Stock issuable upon exercise of the
Agent Warrant even if such exercise has not been effected.

          (h) "Registration Statement" means a registration statement of the
Company filed under the Securities Act and covering the Registrable Securities.

          (i) "Rightsholders" means the Purchasers, the Agent and any persons or
entities to whom the rights granted under this Agreement are transferred by any
Purchaser, Agent or his or its successors or assigns pursuant to Section 9 of
this Agreement.

          (j) "Securities Act" means the Securities Act of 1933, as amended, or
any successor federal statute, and the rules and regulations of the Commission
issued under such Act, as they each may, from time to time, be in effect.

     2. Registration

          (a) The Company shall use its best efforts to prepare and file with
the Commission a Registration Statement (the "Primary Registration Statement")
covering the resale of all of the Registrable Securities and such other shares
of Common Stock as the Company may be required to include pursuant to
registration rights agreements with other Persons within 60 days of the date
hereof. The Company shall use its best efforts to have the Primary Registration

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Statement declared effective by the Commission within 90 days after the date the
Primary Registration Statement is filed or as soon as possible thereafter.

          (b) The Company shall be permitted hereunder to amend the Registration
Statement filed by the Company pursuant to Section 2(a) to cover the resale of
any Interest Shares issued or to be issued by the Company, without the need to
obtain any consent of the Rightsholders, whether such amendment is filed as a
pre-effective or post-effective basis. In addition, the Company may file
hereunder one or more additional Registration Statements covering the resale of
Interest Shares issued or to be issued by the Company (an "Interest Payment
Registration Statement"). In the event that the Company files an Interest
Payment Registration Statement, the Company and the Rightsholders shall have all
of the rights and obligations with respect to such Interest Payment Registration
Statement and the Interest Shares that the Rightsholders have under this
Agreement with respect to the Primary Registration Statement and the Registrable
Securities.

          (c) The Company shall use its best efforts to cause each Registration
Statement to remain effective until the date on which the Rightsholders do not
hold any Registrable Securities covered by such Registration Statement.

     3. Registration Procedures.

          (a) In connection with the effectiveness of the Registration
Statement, the Company shall furnish to each Rightsholder such reasonable
numbers of copies of the prospectus and such documents incident thereto,
including any amendment of or supplement to the prospectus, as a Rightsholder
from time to time may reasonably request in order to facilitate the disposition
of such Rightsholder's Registrable Securities under the Registration Statement
in conformity with the requirements of the Securities Act.

          (b) The Company shall use its best efforts to register or qualify the
Registrable Securities covered by the Registration Statement under the
securities laws of such states of the United States as the Rightsholders may
reasonably request; provided, however, that the Company shall not be required in
connection with this paragraph (b) to qualify as a foreign corporation or
execute a general consent to service of process in any jurisdiction.

          (c) If the Company has delivered preliminary or final prospectuses to
the Rightsholders and if after having done so the Company determines that the
prospectus and/or the Registration Statement needs to be amended or supplemented
to comply with the requirements of the Securities Act, the Company shall
promptly notify the Rightsholders and, if requested by the Company, the
Rightsholders shall immediately cease making offers or sales of shares under the
Registration Statement and shall return all prospectuses to the Company. The
Company shall as promptly as reasonably practicable prepare and file with the
Commission any required amendment or supplement and following such filing, and,
if applicable, the effectiveness of such filing, shall provide the Rightsholders
with revised or supplemented prospectuses. Following receipt of the revised or
supplemented prospectuses, the Rightsholders shall be free to resume making
offers and sales under the Registration Statement.

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          (d) The Company shall use its best efforts to cause all such
Registrable Securities registered pursuant to this Agreement to be listed on
each securities exchange on which similar securities issued by the Company are
then listed.

     4. Limitations on Registration Rights.

          (a) The Company may, by written notice to the Rightsholders, (i) delay
the filing of, or effectiveness of, a Registration Statement or (ii) suspend a
Registration Statement after effectiveness and require that the Rightsholders
immediately cease sales of shares pursuant to the Registration Statement, in the
event that the Company is engaged in any activity or transaction or preparations
or negotiations for any activity or transaction that the Company desires to keep
confidential for business reasons, if the Company determines in good faith that
the public disclosure requirements imposed on the Company under the Securities
Act in connection with the Registration Statement would require disclosure of
such activity, transaction, preparations or negotiations.

          (b) If the Company requires the Rightsholders to cease sales of shares
pursuant to paragraph (a) above, the Company shall, as promptly as practicable
following the termination of the circumstance which entitled the Company to do
so, take such actions as may be necessary to reinstate the effectiveness of the
Registration Statement and/or give written notice to all Rightsholders
authorizing them to resume sales pursuant to the Registration Statement. If as a
result thereof the prospectus included in the Registration Statement has been
amended to comply with the requirements of the Securities Act, the Company shall
enclose such revised prospectus with the notice to Rightsholders given pursuant
to this paragraph (b), and the Rightsholders shall make no offers or sales of
shares pursuant to the Registration Statement other than by means of such
revised prospectus.

          (c) Notwithstanding the foregoing, the Company may not (i) delay the
filing of, or the effectiveness of, a Registration Statement or (ii) suspend a
Registration Statement, pursuant to paragraph (a) above on more than two
occasions during any 12-month period or for more than 60 days per such occasion.

     5. Obligations of the Rightsholders.

          (a) The Company shall not be required to include any Registrable
Securities in a Registration Statement unless such Rightsholder shall have
furnished to the Company such information regarding itself, the Registrable
Securities held by it and the intended method of disposition of the Registrable
Securities held by it as shall be reasonably required by the Company to effect
the effectiveness of the Registration Statement and unless such Rightsholder
shall have executed such documents in connection with the Registration Statement
as the Company may reasonably request. Each Rightsholder shall promptly notify
the Company of any material change with respect to such information previously
provided to the Company by such Rightsholder, including without limitation
notice of the sale by the Rightsholder of any Registrable Securities.

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          (b) Each Rightsholder agrees to cooperate with the Company as
reasonably requested by the Company in connection with the preparation and
filing of the Registration Statement hereunder.

     6. Expenses of Registration. The Company shall pay the expenses incurred by
it in complying with its obligations under this Agreement, including all
registration and filing fees, exchange listing fees, fees and expenses of
counsel for the Company, and fees and expenses of accountants for the Company,
but excluding (a) any brokerage fees, selling commissions or underwriting
discounts incurred by the Rightsholders in connection with sales under the
Registration Statement and (b) the fees and expenses of any counsel retained by
Rightsholders.

     7. Indemnification and Contribution.

          (a) In the event of any registration of any of the Registrable
Securities under the Securities Act pursuant to this Agreement, the Company will
indemnify and hold harmless each Rightsholder, each of its officers, directors
and partners, and each underwriter of such Registrable Securities, if any, and
each other person, if any, who controls such Rightsholder or underwriter within
the meaning of the Securities Act or the Exchange Act against any and all
losses, claims, damages or liabilities, joint or several, to which such
Rightsholder, underwriter or controlling person may become subject under the
Securities Act, the Exchange Act, state securities or Blue Sky laws or
otherwise, insofar as such losses, claims, damages or liabilities (or actions in
respect thereof) arise out of or are based upon (i) any untrue statement or
alleged untrue statement of any material fact contained in the Registration
Statement, registering such Registrable Securities, any preliminary prospectus
or final prospectus contained in such Registration Statement, or any amendment
or supplement to such Registration Statement or (ii) the omission or alleged
omission to state a material fact required to be stated therein or necessary to
make the statements therein not misleading; and the Company will reimburse such
Rightsholder, underwriter and each such controlling person for any legal or any
other expenses reasonably incurred by such Rightsholder, underwriter or
controlling person in connection with investigating or defending any such loss,
claim, damage, liability or action; provided, however, that the Company will not
be liable in any such case to the extent that any such loss, claim, damage,
liability or action arises out of or is based upon any untrue statement or
omission made in such Registration Statement, preliminary prospectus or final
prospectus, or any such amendment or supplement, in reliance upon and in
conformity with information furnished to the Company by or on behalf of such
Rightsholder, underwriter or controlling person and stated to be specifically
for use in connection with such Registration Statement; and provided further
that the foregoing indemnity agreement is subject to the condition that, insofar
as it relates to any untrue statement, alleged untrue statement, omission or
alleged omission made in any Registration Statement, prospectus or amendment or
supplement that was eliminated, remedied or cured by the Company, such indemnity
agreement shall not inure to the benefit of any Rightsholder from whom the
Person asserting any loss, claim, damage or liability purchased the Registrable
Securities if a copy of the Registration Statement, prospectus, amendment or
supplement was provided by the Company to the Rightsholder but was not given or
sent to such Person by the Rightsholder prior to written confirmation of such
sale.

          (b) Each Rightsholder, severally and not jointly, will indemnify and
hold harmless the Company, each of its directors and officers and each
underwriter (if any) and each

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person, if any, who controls the Company or any such underwriter within the
meaning of the Securities Act or the Exchange Act, against any losses, claims,
damages or liabilities, joint or several, to which the Company, such directors
and officers, underwriter or controlling person may become subject under the
Securities Act, Exchange Act, state securities or Blue Sky laws or otherwise,
insofar as such losses, claims, damages or liabilities (or actions in respect
thereof) arise out of or are based upon (i) any untrue statement or alleged
untrue statement of a material fact contained in such Registration Statement,
any preliminary prospectus or final prospectus contained in such Registration
Statement, or any amendment or supplement to such Registration Statement, or
(ii) any omission or alleged omission to state a material fact required to be
stated therein or necessary to make the statements therein not misleading, if
and to the extent (and only to the extent) that the statement or omission was
made in reliance upon and in conformity with written information relating to
such Rightsholder furnished to the Company by such Rightsholder and stated to be
specifically for use in connection with such Registration Statement, prospectus,
amendment or supplement; provided, however, that the obligations of a
Rightsholder hereunder shall be limited to an amount equal to the net proceeds
to such Rightsholder of Registrable Securities sold in connection with such
registration.

          (c) Each Indemnified Party shall give notice to the Indemnifying Party
promptly after such Indemnified Party has actual knowledge of any claim as to
which indemnity may be sought, and shall permit the Indemnifying Party to assume
the defense of any such claim or any litigation resulting therefrom; provided,
that counsel for the Indemnifying Party, who shall conduct the defense of such
claim or litigation, shall be approved by the Indemnified Party (whose approval
shall not be unreasonably withheld, conditioned or delayed); and, provided,
further, that the failure of any Indemnified Party to give notice as provided
herein shall not relieve the Indemnifying Party of its obligations under this
Section 7 except to the extent that the Indemnifying Party is adversely affected
by such failure. The Indemnified Party may participate in such defense at such
party's expense; provided, however, that the Indemnifying Party shall pay such
expense if the Indemnified Party reasonably concludes based upon written advice
of its counsel that representation of such Indemnified Party by the counsel
retained by the Indemnifying Party would be inappropriate due to actual or
potential differing interests between the Indemnified Party and any other party
represented by such counsel in such proceeding; provided further that in no
event shall the Indemnifying Party be required to pay the expenses of more than
one law firm per jurisdiction as counsel for the Indemnified Party. The
Indemnifying Party also shall be responsible for the expenses of such defense if
the Indemnifying Party does not elect to assume such defense. No Indemnifying
Party, in the defense of any such claim or litigation shall, except with the
consent of each Indemnified Party, consent to entry of any judgment or enter
into any settlement which does not include as an unconditional term thereof the
giving by the claimant or plaintiff to such Indemnified Party of a release from
all liability in respect of such claim or litigation, and no Indemnified Party
shall consent to entry of any judgment or settle such claim or litigation
without the prior written consent of the Indemnifying Party, which consent shall
not be unreasonably withheld, conditioned or delayed.

          (d) In order to provide for just and equitable contribution in
circumstances in which the indemnification provided for in this Section 7 is due
in accordance with its terms but for any reason is held to be unavailable to an
Indemnified Party in respect to any losses, claims, damages and liabilities
referred to herein, then the Indemnifying Party shall, in lieu of indemnifying
such Indemnified Party, contribute to the amount paid or payable by such

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Indemnified Party as a result of such losses, claims, damages or liabilities to
which such party may be subject in such proportion as is appropriate to reflect
the relative fault of the Company on the one hand and the Rightsholders on the
other in connection with the statements or omissions which resulted in such
losses, claims, damages or liabilities, as well as any other relevant equitable
considerations. The relative fault of the Company and the Rightsholders shall be
determined by reference to, among other things, whether the untrue or alleged
untrue statement of material fact related to information supplied by the Company
or the Rightsholders and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.
The Company and the Rightsholders agree that it would not be just and equitable
if contribution pursuant to this Section 7(d) were determined by pro rata
allocation or by any other method of allocation which does not take account of
the equitable considerations referred to above. Notwithstanding the provisions
of this Section 7(d), (i) in no case shall any one Rightsholder be liable or
responsible for any amount in excess of the gross proceeds received by such
Rightsholder from the offering of Registrable Securities and (ii) the Company
shall be liable and responsible for any amount in excess of such proceeds;
provided, however, that no person guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation. Any party entitled to contribution will, promptly after
receipt of notice of commencement of any action, suit or proceeding against such
party in respect of which a claim for contribution may be made against another
party or parties under this Section 7(d), notify such party or parties from whom
contribution may be sought, but the omission so to notify such party or parties
from whom contribution may be sought shall not relieve such party from any other
obligation it or they may have thereunder or otherwise under this Section 7(d)
except to the extent that the party or parties from whom contribution may be
sought are adversely affected. No party shall be liable for contribution with
respect to any action, suit, proceeding or claim settled without its prior
written consent, which consent shall not be unreasonably withheld, conditioned
or delayed.

     8. Reporting. With a view to making available to the Rightsholders the
benefits of Rule 144 promulgated under the Securities Act or any other similar
rule or regulation of the Commission that may at any time permit the
Rightsholders to sell securities of the Company to the public without
registration ("Rule 144"), for so long as Rightsholders continue to own
Registrable Securities, the Company shall use its reasonable efforts to:

          (a) make and keep public information available, as those terms are
understood and defined in Rule 144, and file with the Commission in a timely
manner all reports and other documents required of the Company under the
Securities Act and the Exchange Act; and

          (b) furnish to each Rightsholder, for so long as such Rightsholder
owns Registrable Securities, promptly upon request, (i) a written statement by
the Company, if true, that it has complied with the applicable reporting
requirements of Rule 144, the Securities Act and the Exchange Act, (ii) a copy
of the most recent annual or quarterly report of the Company and (iii) such
other information as may be reasonably requested to permit the Rightsholders to
sell such securities pursuant to Rule 144 without registration.

     9. Assignment of Registration Rights. The rights under this Agreement shall
not be assigned by any Rightsholder except in connection with the transfer of
Registrable Securities by

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such Rightsholder to an affiliate of such Rightsholder, provided that (i) the
Rightsholder agrees in writing with the transferee or assignee to assign such
rights, and a copy of such agreement is furnished to the Company; (ii) the
Company is furnished with written notice of (a) the name and address of such
transferee or assignee, and (b) the securities with respect to which such rights
are being transferred or assigned; (iii) at or before the time the Company
receives the written notice contemplated by clause (ii) of this sentence, the
transferee or assignee agrees in writing with the Company to be bound by all of
the obligations of an Rightsholder under this Agreement; and (iv) such transfer
shall have been conducted in accordance with all applicable federal and state
securities laws.

     10. Amendment of Registration Rights.

          (a) Any provision of this Agreement may be amended and the observance
of any provision of this Agreement may be waived (either generally or in a
particular instance and either retroactively or prospectively), only with the
written consent of the Company and Rightsholders who then hold at least a
majority of the Registrable Securities. Any amendment or waiver effected in
accordance with this Section 10 shall be binding upon each Rightsholder and the
Company. No such amendment shall be effective to the extent that it applies to
less than all of the holders of the Registrable Securities. No consideration
shall be offered or paid to any Person to amend or consent to a waiver or
modification of any provision of any of this Agreement unless the same
consideration also is offered to all of the parties to this Agreement.

          (b) In the event that the Company issues and sells Notes as part of
the Offering after the date hereof, the Company shall have the right to amend
this Agreement without the consent of the Rightsholders to include the
purchasers of such Notes in this Agreement as Purchasers and Rightsholders and
any placement agent or selected dealer that receives warrants in connection with
the sale of such Notes as an Agent and Rightsholder and in connection therewith
to modify the Schedule of Purchasers to include such Purchaser and the Agent
Schedule to include such Agent.

     11. Miscellaneous.

          (a) A Person is deemed to be a holder of Registrable Securities
whenever such Person owns or is deemed to own of record such Registrable
Securities. If the Company receives conflicting instructions, notices or
elections from two or more Persons with respect to the same Registrable
Securities, the Company shall act upon the basis of instructions, notice or
election received from the record owner of such Registrable Securities.

          (b) Any notices, consents, waivers or other communications required or
permitted to be given under the terms of this Agreement must be in writing and
will be deemed to have been delivered: (i) upon receipt, when delivered
personally; (ii) upon receipt, when sent by facsimile; or (iii) two (2) Business
Days after deposit with a reputable overnight delivery service, in each case
properly addressed to the party to receive the same. The addresses and facsimile
numbers for such communications shall be:

     If to the Company:

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<PAGE>
                       Hybridon, Inc.
                       345 Vassar Street
                       Cambridge, MA 02139-4818
                       Telephone: 617-679-5500
                       Facsimile: 617-679-5592
                       Attention: Chief Financial Officer

     with a copy to:

                       Wilmer Cutler Pickering Hale and Dorr LLP
                       60 State Street
                       Boston, MA 02109
                       Telephone: 617-526-6000
                       Facsimile: 617-526-5000
                       Attention: David E. Redlick, Esq.

     If to a Rightsholder, to its address and facsimile number set forth on the
Schedule of Purchasers or on the Agent Schedule, as the case may be, or to such
other address and/or facsimile number and/or to the attention of such other
Person as the recipient party has specified by written notice given to each
other party five (5) days prior to the effectiveness of such change.

     Written confirmation of receipt (A) given by the recipient of such notice,
consent, waiver or other communication, (B) mechanically or electronically
generated by the sender's facsimile machine containing the time, date, recipient
facsimile number and an image of the first page of such transmission, or (C)
provided by a courier or overnight courier service shall be rebuttable evidence
of personal service, receipt by facsimile or receipt from a reputable overnight
delivery service in accordance with clause (i), (ii) or (iii) above,
respectively.

          (c) Failure of any party to exercise any right or remedy under this
Agreement or otherwise, or delay by a party in exercising such right or remedy,
shall not operate as a waiver thereof.

          (d) All questions concerning the construction, validity, enforcement
and interpretation of this Agreement shall be governed by the internal laws of
the State of Delaware, without giving effect to any choice of law or conflict of
law provision or rule (whether of the State of Delaware or any other
jurisdictions) that would cause the application of the laws of any jurisdictions
other than the State of Delaware.

          (e) This Agreement and the documents referenced herein constitute the
entire agreement among the parties hereto with respect to the subject matter
hereof and thereof. There are no restrictions, promises, warranties or
undertakings, other than those set forth or referred to herein and therein. This
Agreement and the documents referenced herein supersede all prior agreements and
understandings among the parties hereto with respect to the subject matter
hereof.

                                       9
<PAGE>
          (f) Subject to the requirements of Section 9 of this Agreement, this
Agreement shall inure to the benefit of and be binding upon the permitted
successors and assigns of each of the parties hereto.

          (g) The headings in this Agreement are for convenience of reference
only and shall not limit or otherwise affect the meaning hereof.

          (h) This Agreement may be executed in identical counterparts, each of
which shall be deemed an original but all of which shall constitute one and the
same agreement. This Agreement, once executed by a party, may be delivered to
the other parties hereto by facsimile transmission of a copy of this Agreement
bearing the signature of the party so delivering this Agreement.

          (i) Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

          (j) All consents and other determinations required to be made by the
Rightsholders pursuant to this Agreement shall be made, unless otherwise
specified in this Agreement, by Rightsholders holding at least a majority of the
Registrable Securities.

          (k) The language used in this Agreement will be deemed to be the
language chosen by the parties to express their mutual intent and no rules of
strict construction will be applied against any party.

          (l) This Agreement is intended for the benefit of the parties hereto
and their respective permitted successors and assigns, and is not for the
benefit of, nor may any provision hereof be enforced by, any other Person.

                  [REMAINDER OF PAGE LEFT BLANK INTENTIONALLY]

                                       10
<PAGE>
     IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be duly executed as of the day and year first above written.

                                        COMPANY:

                                        HYBRIDON, INC.

                                        By: /s/ R. Andersen
                                            ------------------------------------
                                        Name: R.G. Andersen
                                        Title: CFO

                                        PURCHASERS:

                                        Counterpart signature pages attached.

                                        AGENT:

                                        Counterpart signature pages attached.

                                       11
<PAGE>
                                    Exhibit A

                             Schedule of Purchasers

<TABLE>
<CAPTION>
Name and Address               Registrable Securities
----------------               ----------------------
<S>                            <C>
Abdel Raouf M. Abou Anza                 89,888
Hyb Invest I ApS                        898,876
Optima Life Sciences Limited          3,486,236
Saleh Abdullah Alattas                1,179,775
</TABLE>
<PAGE>
Exhibit B

                                 Agent Schedule

<TABLE>
<CAPTION>
Name and Address             Registrable Securities
----------------             ----------------------
<S>                          <C>
Pillar Investments Limited           565,478
</TABLE><PAGE>
                                                                    Exhibit 10.9

THIS WARRANT AND THE WARRANT SHARES SHALL NOT BE SOLD OR TRANSFERRED EXCEPT (A)
  IN ACCORDANCE WITH THE PROVISIONS OF REGULATION S UNDER THE SECURITIES ACT OF
   1933, (B) PURSUANT TO REGISTRATION UNDER THE SECURITIES ACT OF 1933 OR (C)
PURSUANT TO AN AVAILABLE EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF
1933. HEDGING TRANSACTIONS INVOLVING THIS WARRANT AND THE WARRANT SHARES MAY NOT
       BE CONDUCTED UNLESS IN COMPLIANCE WITH THE SECURITIES ACT OF 1933.

           THIS WARRANT AND THE SHARES OF COMMON STOCK ISSUED UPON ITS
                   EXERCISE ARE SUBJECT TO THE RESTRICTIONS ON
                 TRANSFER SET FORTH IN SECTION 5 OF THIS WARRANT

Warrant No. 2005-1                                     Number of Shares: 565,478
                                                         (subject to adjustment)
Date of Issuance: May 24, 2005

                                 HYBRIDON, INC.

                          Common Stock Purchase Warrant

                            (Void after May 24, 2010)

     Hybridon, Inc., a Delaware corporation (the "Company"), for value received,
hereby certifies that Pillar Investments Limited, or its registered assigns (the
"Registered Holder"), is entitled, subject to the terms and conditions set forth
below, to purchase from the Company, at any time, or from time to time, on or
after May 24, 2005 and on or before 5:00 p.m. (Boston time) on May 24, 2010,
565,478 shares of Common Stock, $0.001 par value per share, of the Company
("Common Stock"), at a purchase price of $0.89 per share. The shares purchasable
upon exercise of this Warrant, and the purchase price per share, each as
adjusted from time to time pursuant to the provisions of this Warrant, are
hereinafter referred to as the "Warrant Shares" and the "Purchase Price,"
respectively.

     1. Exercise.

          (a) Exercise Process. The Registered Holder may, at its option, elect
to exercise this Warrant, in whole or in part and at any time, or from time to
time, by surrendering this Warrant, with the purchase form appended hereto as
Exhibit I duly executed by or on behalf of the Registered Holder, at the
principal office of the Company, or at such other office or agency as the
Company may designate, accompanied by payment in full, in lawful money of the
United States, of the Purchase Price payable in respect of the number of Warrant
Shares purchased upon such exercise.

          (b) Exercise Date. Each exercise of this Warrant shall be deemed to
have been effected immediately prior to the close of business on the day on
which this Warrant shall have been surrendered to the Company as provided in
subsection 1(a) above (the "Exercise Date"). At such time, the person or persons
in whose name or names any certificates for Warrant Shares shall be issuable
upon such exercise as provided in subsection 1(c) below shall be deemed
<PAGE>
to have become the holder or holders of record of the Warrant Shares represented
by such certificates.

          (c) Issuance of Common Stock Certificates. As soon as practicable
after the exercise of this Warrant in whole or in part, and in any event within
10 days thereafter, the Company, at its expense, will cause to be issued in the
name of, and delivered to, the Registered Holder, or as the Registered Holder
(upon payment by the Registered Holder of any applicable transfer or withholding
taxes) may direct:

               (i) a certificate or certificates for the number of full Warrant
Shares to which the Registered Holder shall be entitled upon such exercise plus,
in lieu of any fractional share to which the Registered Holder would otherwise
be entitled, cash in an amount determined pursuant to Section 3 hereof; and

               (ii) in case such exercise is in part only, a new warrant or
warrants (dated the date hereof) of like tenor, calling in the aggregate on the
face or faces thereof for the number of Warrant Shares equal (without giving
effect to any adjustment therein) to the number of such shares called for on the
face of this Warrant minus the number of Warrant Shares for which this Warrant
was so exercised.

          (d) Exercise by Non-U.S. Person. It shall be a condition to the
exercise of this Warrant by a Registered Holder that is not a U.S. Person (as
defined under the Securities Act of 1933, as amended (the "Securities Act"))
that such Registered Holder certify in writing to the Company that it is not a
U.S. Person and that this Warrant is not being exercised on behalf of a U.S.
Person.

     2. Adjustments.

          (a) Adjustment for Stock Splits and Combinations. If the Company shall
at any time, or from time to time after the date on which this Warrant was first
issued (or, if this Warrant was issued upon partial exercise of, or in
replacement of, another warrant of like tenor, then the date on which such
original warrant was first issued) (either such date being referred to as the
"Original Issue Date") effect a subdivision of the outstanding Common Stock, the
Purchase Price then in effect immediately before that subdivision shall be
proportionately decreased. If the Company shall at any time, or from time to
time, after the Original Issue Date combine the outstanding shares of Common
Stock, the Purchase Price then in effect immediately before the combination
shall be proportionately increased. Any adjustment under this paragraph shall
become effective at the close of business on the date the subdivision or
combination becomes effective.

          (b) Adjustment for Certain Dividends and Distributions. In the event
the Company at any time, or from time to time after the Original Issue Date
shall make or issue, or fix a record date for the determination of holders of
Common Stock entitled to receive, a dividend or other distribution payable in
additional shares of Common Stock, then and in each such event the Purchase
Price then in effect immediately before such event shall be decreased as of the
time of such issuance or, in the event such a record date shall have been fixed,
as of the

                                      -2-
<PAGE>
close of business on such record date, by multiplying the Purchase Price then in
effect by a fraction:

               (i) the numerator of which shall be the total number of shares of
Common Stock issued and outstanding immediately prior to the time of such
issuance or the close of business on such record date, and

               (ii) the denominator of which shall be the total number of shares
of Common Stock issued and outstanding immediately prior to the time of such
issuance or the close of business on such record date plus the number of shares
of Common Stock issuable in payment of such dividend or distribution;

provided, however, that if such record date shall have been fixed and such
dividend is not fully paid or if such distribution is not fully made on the date
fixed therefor, the Purchase Price shall be recomputed accordingly as of the
close of business on such record date and thereafter the Purchase Price shall be
adjusted pursuant to this paragraph as of the time of actual payment of such
dividends or distributions.

          (c) Adjustment in Number of Warrant Shares. When any adjustment is
required to be made in the Purchase Price pursuant to subsections 2(a) or 2(b)
above, the number of Warrant Shares purchasable upon the exercise of this
Warrant shall be changed to the number determined by dividing (i) an amount
equal to the number of shares issuable upon the exercise of this Warrant
immediately prior to such adjustment, multiplied by the Purchase Price in effect
immediately prior to such adjustment, by (ii) the Purchase Price in effect
immediately after such adjustment.

          (d) Adjustments for Other Dividends and Distributions. In the event
the Company at any time, or from time to time after the Original Issue Date
shall make or issue, or fix a record date for the determination of holders of
Common Stock entitled to receive, a dividend or other distribution payable in
securities of the Company (other than shares of Common Stock) or in cash or
other property (other than regular cash dividends paid out of earnings or earned
surplus, determined in accordance with generally accepted accounting
principles), then and in each such event provision shall be made so that the
Registered Holder shall receive upon exercise hereof, in addition to the number
of shares of Common Stock issuable hereunder, the kind and amount of securities
of the Company, cash or other property which the Registered Holder would have
been entitled to receive had this Warrant been exercised on the date of such
event and had the Registered Holder thereafter, during the period from the date
of such event to and including the Exercise Date, retained any such securities
receivable during such period, giving application to all adjustments called for
during such period under this Section 2 with respect to the rights of the
Registered Holder.

          (e) Adjustment for Reorganization. If there shall occur any
reorganization, recapitalization, reclassification, consolidation or merger
involving the Company in which the Common Stock is converted into or exchanged
for securities, cash or other property (other than a transaction covered by
subsections 2(a), 2(b) or 2(d)) (collectively, a "Reorganization"), then,
following such Reorganization, the Registered Holder shall receive upon exercise
hereof the kind and amount of securities, cash or other property which the
Registered Holder would have been

                                      -3-
<PAGE>
entitled to receive pursuant to such Reorganization if such exercise had taken
place immediately prior to such Reorganization. In any such case, appropriate
adjustment (as determined in good faith by the Board of Directors of the Company
(the "Board")) shall be made in the application of the provisions set forth
herein with respect to the rights and interests thereafter of the Registered
Holder, to the end that the provisions set forth in this Section 2 (including
provisions with respect to changes in and other adjustments of the Purchase
Price) shall thereafter be applicable, as nearly as reasonably may be, in
relation to any securities, cash or other property thereafter deliverable upon
the exercise of this Warrant.

          (f) Certificate as to Adjustments. Upon the occurrence of each
adjustment or readjustment of the Purchase Price pursuant to this Section 2, the
Company at its expense shall, as promptly as reasonably practicable but in any
event not later than 30 days thereafter, compute such adjustment or readjustment
in accordance with the terms hereof and furnish to the Registered Holder a
certificate setting forth such adjustment or readjustment (including the kind
and amount of securities, cash or other property for which this Warrant shall be
exercisable and the Purchase Price) and showing in detail the facts upon which
such adjustment or readjustment is based. The Company shall, as promptly as
reasonably practicable after the written request at any time of the Registered
Holder (but in any event not later than 30 days thereafter), furnish or cause to
be furnished to the Registered Holder a certificate setting forth (i) the
Purchase Price then in effect and (ii) the number of shares of Common Stock and
the amount, if any, of other securities, cash or property which then would be
received upon the exercise of this Warrant.

     3. Fractional Shares. The Company shall not be required upon the exercise
of this Warrant to issue any fractional shares, but shall pay the value thereof
to the Registered Holder in cash on the basis of the Fair Market Value per share
of Common Stock. The "Fair Market Value" per share of Common Stock shall be
determined as follows:

          (a) If the Common Stock is listed on a national securities exchange,
the Nasdaq National Market, the Nasdaq SmallCap Market, the OTC Bulletin Board
or another nationally recognized trading system as of the Exercise Date, the
Fair Market Value per share of Common Stock shall be deemed to be the average of
the high and low reported sale prices per share of Common Stock thereon for the
five consecutive trading day period immediately preceding the Exercise Date;
provided that if the Common Stock is not so listed during such period, the Fair
Market Value per share of Common Stock shall be determined pursuant to clause
3(b).

          (b) If the Common Stock is not listed on a national securities
exchange, the Nasdaq National Market, the Nasdaq SmallCap Market, the OTC
Bulletin Board or another nationally recognized trading system as of the
Exercise Date, the Fair Market Value per share of Common Stock shall be deemed
to be the amount most recently determined by the Board or an authorized
committee of the Board to represent the fair market value per share of the
Common Stock (including without limitation a determination for purposes of
granting Common Stock options or issuing Common Stock under any plan, agreement
or arrangement with employees of the Company).

     4. Redemption of Warrants.

                                      -4-
<PAGE>
          (a) Subject to the terms of this Section 4, the Company shall have the
right to redeem this Warrant for a redemption price (the "Redemption Price")
equal to the result obtained by multiplying (i) $0.01 by (ii) the number of
Warrant Shares that the Registered Holder is entitled to purchase upon exercise
of this Warrant immediately prior to the termination of this Warrant under
Section 4(d) below (such Redemption Price being subject to adjustment for stock
splits, stock dividends, combinations, recapitalizations, reclassifications, and
similar transactions affecting the Common Stock).

          (b) The Company shall exercise this redemption right by providing at
least 30 days' prior written notice to the Registered Holder of such redemption
(the "Redemption Notice"). Such Redemption Notice shall be provided to the
Registered Holder in accordance with Section 10 of this Warrant. The Redemption
Notice shall specify the time, manner and place of redemption, including without
limitation the date on which this Warrant shall be redeemed (the "Redemption
Date") and the Redemption Price payable to the Registered Holder (assuming that
this Warrant is not exercised on or prior to the Redemption Date).

          (c) Notwithstanding the foregoing, the Company may not redeem this
Warrant or provide the Redemption Notice to the Registered Holder unless the
closing sales price of the Common Stock on each day of a 20 consecutive trading
day period ending within 30 days prior to the date the Company provides the
Redemption Notice to the Registered Holder is greater than or equal to $1.78
(subject to adjustment for stock splits, stock dividends, combinations,
recapitalizations, reclassifications, and similar transactions affecting the
Common Stock); provided, however, that the Company may not redeem this Warrant
or provide the Redemption Notice on or before November 24, 2005.

          (d) This Warrant shall cease to be exercisable and shall be terminated
and of no further force or effect effective at 5:00 p.m. (Boston Time) on the
Redemption Date. If the Registered Holder does not exercise this Warrant on or
prior to the Redemption Date, the Registered Holder shall surrender this Warrant
to the Company on the Redemption Date for cancellation. From and after the
Redemption Date, the Registered Holder's sole right hereunder shall be to
receive the Redemption Price, without interest, upon presentation and surrender
of this Warrant for cancellation.

     5. Transfers, etc.

          (a) Neither this Warrant nor the Warrant Shares shall be sold or
transferred unless either (i) they first shall have been registered under the
Securities Act, or (ii) the Company first shall have been furnished with an
opinion of legal counsel, reasonably satisfactory to the Company, to the effect
that such sale or transfer is exempt from the registration requirements of the
Securities Act. Notwithstanding the foregoing, no registration or opinion of
counsel shall be required for a transfer made in accordance with Rule 144 under
the Securities Act.

          (b) Each certificate representing Warrant Shares shall bear a legend
substantially in the following form:

               "The securities represented by this certificate have not been
               registered under the Securities Act of 1933, as amended, and may
               not be offered,

                                      -5-
<PAGE>
               sold or otherwise transferred, pledged or hypothecated unless and
               until such securities are registered under such Act or an opinion
               of counsel satisfactory to the Company is obtained to the effect
               that such registration is not required."

The foregoing legend shall be removed from the certificates representing any
Warrant Shares, at the request of the holder thereof, at such time as they
become eligible for resale pursuant to Rule 144(k) under the Securities Act.

          (c) In the case of a Registered Holder that is a non-U.S. Person:

               (i) THIS WARRANT AND THE WARRANT SHARES HAVE NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933 AND THIS WARRANT MAY NOT BE EXERCISED BY OR ON
BEHALF OF A U.S. PERSON UNLESS REGISTERED UNDER THE SECURITIES ACT OF 1933 OR AN
EXEMPTION FROM SUCH REGISTRATION IS AVAILABLE.

               (ii) This Warrant and the Warrant Shares shall not be sold or
transferred except (A) in accordance with the provisions of Regulation S under
the Securities Act, (B) pursuant to registration under the Securities Act or (C)
pursuant to an available exemption from registration under the Securities Act.
Hedging transactions involving this Warrant and the Warrant Shares may not be
conducted unless in compliance with the Securities Act.

               (iii) Notwithstanding Section 5(b) to the contrary, each
certificate representing Warrant Shares issued to a Registered Holder that is a
non-U.S. Person shall bear a legend substantially in the following form:

     "These shares have not been registered under the Securities Act of 1933.
     They may not be offered or transferred by sale, assignment, pledge or
     otherwise unless (i) a registration statement for the shares under the
     Securities Act of 1933 is in effect or (ii) the corporation has received an
     opinion of counsel, which opinion is satisfactory to the corporation, to
     the effect that such registration is not required under the Securities Act
     of 1933 or (iii) such offer or transfer is made in accordance with the
     provisions of Regulation S under the Securities Act of 1933. Hedging
     transactions involving these shares may not be conducted unless in
     compliance with the Securities Act of 1933."

          (d) The Company will maintain a register containing the name and
address of the Registered Holder of this Warrant. The Registered Holder may
change its address as shown on the warrant register by written notice to the
Company requesting such change.

          (e) Notwithstanding Section 5(a) above, a Registered Holder which is
an entity may transfer this Warrant, in whole, to a wholly owned subsidiary of
such entity, a Registered Holder which is a partnership may transfer this
Warrant, in whole, to a partner of such partnership or a retired partner of such
partnership or to the estate of any such partner or retired partner, a
Registered Holder which is a limited liability company may transfer this
Warrant, in whole, to a member of such limited liability company or a retired
member or to the

                                      -6-
<PAGE>
estate of any such member or retired member and a Registered Holder who is an
individual may transfer this Warrant, in whole, to such individual's spouse,
children, parents, siblings, grandchildren or any trust established exclusively
for the benefit of one or more of the foregoing individuals, or by will or the
laws of descent and distribution (in each case, a "Permitted Transferee"). This
Warrant and all rights hereunder are transferable to a Permitted Transferee, in
whole, upon surrender of this Warrant with a properly executed assignment (in
the form of Exhibit II hereto) at the principal office of the Company (or, if
another office or agency has been designated by the Company for such purpose,
then at such other office or agency).

     6. No Impairment. The Company will not, by amendment of its charter or
through any reorganization, transfer of assets, consolidation, merger,
dissolution, issue or sale of securities or any other voluntary action, avoid or
seek to avoid the observance or performance of any of the terms of this Warrant,
but will at all times in good faith assist in the carrying out of all such terms
and in the taking of all such action as may be necessary or appropriate in order
to protect the rights of the Registered Holder against impairment.

     7. Notices of Record Date, etc. In the event:

          (a) the Company shall take a record of the holders of its Common Stock
(or other stock or securities at the time deliverable upon the exercise of this
Warrant) for the purpose of entitling or enabling them to receive any dividend
or other distribution, or to receive any right to subscribe for or purchase any
shares of stock of any class or any other securities, or to receive any other
right; or

          (b) of any capital reorganization of the Company, any reclassification
of the Common Stock of the Company, any consolidation or merger of the Company
with or into another corporation (other than a consolidation or merger in which
the Company is the surviving entity and its Common Stock is not converted into
or exchanged for any other securities or property), or any transfer of all or
substantially all of the assets of the Company; or

          (c) of the voluntary or involuntary dissolution, liquidation or
winding-up of the Company,

then, and in each such case, the Company will send or cause to be sent to the
Registered Holder a notice specifying, as the case may be, (i) the record date
for such dividend, distribution or right, and the amount and character of such
dividend, distribution or right, or (ii) the effective date on which such
reorganization, reclassification, consolidation, merger, transfer, dissolution,
liquidation or winding-up is to take place, and the time, if any is to be fixed,
as of which the holders of record of Common Stock (or such other stock or
securities at the time deliverable upon the exercise of this Warrant) shall be
entitled to exchange their shares of Common Stock (or such other stock or
securities) for securities or other property deliverable upon such
reorganization, reclassification, consolidation, merger, transfer, dissolution,
liquidation or winding-up. Such notice shall be sent at least 10 days prior to
the record date or effective date for the event specified in such notice.

     8. Reservation of Stock. The Company will at all times reserve and keep
available, solely for issuance and delivery upon the exercise of this Warrant,
such number of Warrant

                                      -7-
<PAGE>
Shares and other securities, cash and/or property, as from time to time shall be
issuable upon the exercise of this Warrant.

     9. Exchange or Replacement of Warrants.

          (a) Upon the surrender by the Registered Holder, properly endorsed, to
the Company at the principal office of the Company, the Company will, subject to
the provisions of Section 5 hereof, issue and deliver to or upon the order of
the Registered Holder, at the Company's expense, a new Warrant or Warrants of
like tenor, in the name of the Registered Holder or as the Registered Holder
(upon payment by the Registered Holder of any applicable transfer taxes) may
direct, calling in the aggregate on the face or faces thereof for the number of
shares of Common Stock (or other securities, cash and/or property) then issuable
upon exercise of this Warrant.

          (b) Upon receipt of evidence reasonably satisfactory to the Company of
the loss, theft, destruction or mutilation of this Warrant and (in the case of
loss, theft or destruction) upon delivery of an indemnity agreement (with surety
if reasonably required) in an amount reasonably satisfactory to the Company, or
(in the case of mutilation) upon surrender and cancellation of this Warrant, the
Company will issue, in lieu thereof, a new Warrant of like tenor.

     10. Notices. All notices and other communications from the Company to the
Registered Holder in connection herewith shall be mailed by certified or
registered mail, postage prepaid, or sent via a reputable overnight courier
service to the address last furnished to the Company in writing by the
Registered Holder. All notices and other communications from the Registered
Holder to the Company in connection herewith shall be mailed by certified or
registered mail, postage prepaid, or sent via a reputable overnight courier
service to the Company at its principal office set forth below. If the Company
should at any time change the location of its principal office to a place other
than as set forth below, it shall give prompt written notice to the Registered
Holder and thereafter all references in this Warrant to the location of its
principal office at the particular time shall be as so specified in such notice.
All such notices and communications shall be deemed delivered (i) two business
days after being sent by certified or registered mail, return receipt requested,
postage prepaid, or (ii) two business days after being sent via a reputable
overnight courier service.

     11. No Rights as Stockholder. Until the exercise of this Warrant, the
Registered Holder shall not have or exercise any rights by virtue hereof as a
stockholder of the Company. Notwithstanding the foregoing, in the event (i) the
Company effects a split of the Common Stock by means of a stock dividend and the
Purchase Price of and the number of Warrant Shares are adjusted as of the date
of the distribution of the dividend (rather than as of the record date for such
dividend), and (ii) the Registered Holder exercises this Warrant between the
record date and the distribution date for such stock dividend, the Registered
Holder shall be entitled to receive, on the distribution date, the stock
dividend with respect to the shares of Common Stock acquired upon such exercise,
notwithstanding the fact that such shares were not outstanding as of the close
of business on the record date for such stock dividend.

     12. Amendment or Waiver. Any term of this Warrant may be amended or waived
only by an instrument in writing signed by the party against which enforcement
of the change or

                                      -8-
<PAGE>
waiver is sought. No waivers of any term, condition or provision of this
Warrant, in any one or more instances, shall be deemed to be, or construed as, a
further or continuing waiver of any such term, condition or provision.

     13. Section Headings. The section headings in this Warrant are for the
convenience of the parties and in no way alter, modify, amend, limit or restrict
the contractual obligations of the parties.

     14. Governing Law. This Warrant will be governed by and construed in
accordance with the internal laws of the State of Delaware (without reference to
the conflicts of law provisions thereof).

     15. Facsimile Signatures. This Warrant may be executed by facsimile
signature.

     16. Acceptance by Registered Holder. By acquiring and accepting this
Warrant, the Registered Holder shall be deemed to have agreed and accepted the
terms and conditions of this Warrant.

     EXECUTED as of the Date of Issuance indicated above.

                                        HYBRIDON, INC.

                                        By: R. Andersen
                                            ------------------------------------
                                        Title: CFO

                                      -9-
<PAGE>
                                                                       EXHIBIT I

                                  PURCHASE FORM

To: Hybridon, Inc.                                            Dated:____________

     The undersigned, pursuant to the provisions set forth in the attached
Warrant (No. ______), hereby elects to purchase __________ shares of the Common
Stock of Hybridon, Inc. covered by such Warrant.

     The undersigned herewith makes a payment of $___________ representing the
full purchase price for such shares at the price per share provided for in such
Warrant.

                                        Signature:
                                                   -----------------------------

                                        Address:
                                                 -------------------------------

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

                                      -10-
<PAGE>
                                                                      EXHIBIT II

                                 ASSIGNMENT FORM

     FOR VALUE RECEIVED, ________________________________________ hereby sells,
assigns and transfers all of the rights of the undersigned under the attached
Warrant (No. ____) with respect to all of the shares of Common Stock of
Hybridon, Inc. covered thereby set forth below, unto:

<TABLE>
<CAPTION>
Name of Assignee                     Address                       No. of Shares
----------------                     -------                       -------------
<S>                                  <C>                           <C>

</TABLE>

Dated:                                  Signature:
       ------------------                          -----------------------------

Signature Guaranteed:

By:
    ---------------------------------

The signature should be guaranteed by an eligible guarantor institution (banks,
stockbrokers, savings and loan associations and credit unions with membership in
an approved signature guarantee medallion program) pursuant to Rule 17Ad-15
under the Securities Exchange Act of 1934.

                                      -11-

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