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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

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

                                    FORM 8-K

                                 CURRENT REPORT

                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


       Date of Report (Date of earliest event reported): January 22, 1998


                                     0-27352
                            (Commission File Number)

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

                                 HYBRIDON, INC.
             (Exact name of registrant as specified in its charter)

        Delaware                                            3072298
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  (State of Incorporation)                               (IRS Employer
                                                      Identification Number)

               620 Memorial Drive, Cambridge, Massachusetts 02139
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              (Address of registrant's principal executive office)

                                 (617) 528-7000
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                         (Registrant's telephone number)

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


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ITEM 5. Other Events


         On January 22, 1998,  Hybridon,  Inc.  (the  "Company")  issued a press
release  announcing  that the Company  has  determined  not to proceed  with the
offering described in its press release dated November 18, 1997 and filed with a
Current  Report on Form 8-K on that  date.  In lieu  thereof,  the  Company  has
commenced a private offering,  on a best efforts basis, to overseas investors in
accordance  with  Regulation  S  under  the  Securities  Act of  1933  of  units
("Units"),  each Unit consisting of $100,000  principal amount of Notes due 2007
and certain  warrants to purchase  Common  Stock,  pursuant to which the Company
intends to offer (together with a private offering,  on a best efforts basis, on
substantially  the same  terms  which the  Company  may  commence  in the United
States) a maximum of 400 Units (with an over-allotment option covering an
additional  150 Units),  at a purchase  price of $100,00 per Unit. A copy of the
release has been filed with this Current  Report on Form 8-K as Exhibit 99.1 and
is incorporated herein by reference.


ITEM 7.   Financial Statements, Pro Forma Financial Information and Exhibits

          (c) Exhibits.

Exhibit Number                           Title
- --------------                           -----

     99.1                   Press Release dated January 22, 1998






                                   SIGNATURES


         Pursuant to the  requirements  of the Securities  Exchange Act of 1934,
the  registrant  has duly  caused  this report to be signed on its behalf by the
undersigned, thereunto duly authorized.


                                         HYBRIDON, INC.

                                         By:   /s/ E. ANDREWS GRINSTEAD, III
                                               -----------------------------
                                               Name:   E. Andrews Grinstead, III
                                               Title:  Chairman of the Board, 
                                                       President and Chief
                                                       Executive Officer

                                         Date:  January 22, 1998




FOR IMMEDIATE RELEASE

                                                            Debra J. Manjourides
                                                        Corporate Communications
                                                                    617.528.7523


         HYBRIDON ANNOUNCES COMMENCEMENT OF PRIVATE PLACEMENT OF UP TO
                                  $40,000,000


CAMBRIDGE,  MA.,  January  22,  1998 --  Hybridon,  Inc.  (OTC-BB:  HYBN)  today
announced that it has commenced a private offering,  on a best efforts basis, to
overseas  investors in accordance  with Regulation S under the Securities Act of
1933, as amended (the "Offering"),  of units ("Units"),  each Unit consisting of
$100,000  principal  amount of Notes due 2007  ("Offering  Notes")  and  certain
warrants  ("Warrants") to purchase Common Stock, pursuant to which it intends to
offer a minimum of 20 Units and  (together  with a private  offering,  on a best
efforts basis, on substantially the same terms which the Company may commence in
the  United  States)  a  maximum  of 400 Units  (with an  over-allotment  option
covering an additional 150 Units), at a purchase price of $100,000 per Unit. The
Offering Notes are automatically convertible into preferred stock of the Company
under certain  circumstances  described  below;  the holders of the Company's 9%
Convertible  Subordinated  Notes due 2004 (the "9% Notes") have consented to the
Offering and its terms.

The  Company  expects  to use the  net  proceeds  of the  Offering  for  general
corporate  purposes,  primarily  research  and product  development  activities,
including  costs  of  preparing   Investigational   New  Drug  applications  and
conducting  preclinical  studies and clinical trials, the payment of payroll and
other accounts payable and for debt service.

The  Company  also  announced  that it has  determined  not to proceed  with the
proposed offering of Common Stock announced on November 18, 1997.

THE SECURITIES OFFERED IN THE OFFERING AND THE SECURITIES ISSUABLE UPON EXERCISE
OR  CONVERSION  THEREOF  HAVE NOT BEEN,  AND WILL NOT BE,  REGISTERED  UNDER THE
SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE OFFERED OR SOLD IN THE UNITED
STATES  ABSENT  REGISTRATION  OR  AN  APPLICABLE   EXEMPTION  FROM  REGISTRATION
REQUIREMENTS.

The Company intends to commence an exchange offer to the holders of its 9% Notes
to exchange such 9% Notes for  preferred  stock and warrants of the Company (the
"Exchange  Offer").  There can be no assurance  that such Exchange Offer will be
successful.  However,  the Offering  Notes  (which rank senior to  approximately
$40,000,000  principal amount of the 9% Notes) provide that if the holders of at
least $40,000,000  principal amount (or 80%) of the 9% Notes accept the proposed
Exchange  Offer and at least  $20,000,000  of net  proceeds  are received in the
Offering,   the  Offering  Notes  will  automatically  convert  into  shares  of
convertible  preferred stock of the Company (the "Conversion  Preferred  Stock")
which will rank junior to the preferred  stock  issuable in the Exchange  Offer.
The Offering Notes are not  convertible  at the option of the holder.  Each Unit
sold in the  Offering  will  include  Warrants to  purchase  15% (or, in certain
circumstances,  20%) of the  number of shares of  Common  Stock  underlying  the
Conversion  Preferred Stock  underlying the Offering Notes included in such Unit
and may include additional  warrants in certain  circumstances  described below.
The Conversion  Preferred Stock, if issued,  and Warrants are convertible  into,
and exercisable for, Common Stock at a conversion or exercise price equal to the
lowest of (i) 80% of the average closing bid price of the Company's Common Stock
for the 30  consecutive  trading days  immediately  preceding any closing in the
Offering or (ii) 80% of the average  closing bid price of the  Company's  Common
Stock for the five consecutive trading days immediately preceding any closing in
the Offering; provided, however, that if on the termination date of the Offering
the  Company has not  received at least  $20,000,000  in net  proceeds  from the
Offering  or the  holders of less than  $40,000,000  principal  amount of the 9%
Notes accept the proposed Exchange Offer,  investors will be entitled to receive
additional  warrants to purchase,  at an exercise  price of $0.001 per share,  a
number of shares of Common  Stock equal to 100% of the Common  Stock  underlying
the Conversion  Preferred Stock  underlying the Offering Notes purchased by such
investors,  in which case the Offering Notes will not be convertible into equity
securities.  It is expected that the Conversion Preferred Stock, if issued, will
provide  that if the market  price of the Common  Stock is less than 125% of the
conversion price of the Conversion  Preferred Stock on the one-year  anniversary
of the final closing date of the Offering, the conversion price will be adjusted
(the  "Reset") to be the greater of (a) the market price at such time divided by
1.25 and (b) 50% of the conversion  price of the Conversion  Preferred  Stock at
such time; it is expected that holders of the  Conversion  Preferred  Stock will
also receive additional  Warrants to purchase a number of shares of Common Stock
equal to 50% of the  additional  number of shares of Common Stock  issuable upon
conversion of the Conversion Preferred Stock as a result of the Reset.

Hybridon, headquartered in Cambridge, Massachusetts, is engaged in the discovery
and  development  of genetic  medicines for the  treatment of certain  diseases,
based primarily on antisense  technology.  Antisense  technology attempts to use
synthetic  segments of DNA and RNA to stop the production of  disease-associated
proteins by  interacting  at the genetic level with target  strands of messenger
RNA.

This press release contains forward-looking  statements that involve a number of
risks and uncertainties. The statements contained in this press release that are
not historical are forward-looking  statements within the meaning of Section 27A
of the  Securities  Act of 1933, as amended,  and Section 21E of the  Securities
Exchange  Act  of  1934,  as  amended,   including   statements   regarding  the
expectations,  beliefs, intentions or strategies regarding the future. There can
be no assurance (i) as to the amount of proceeds  which may be received from the
Offering or (ii) that the Offering Notes will convert into equity  securities of
the  Company.  Furthermore,  there  can be no  assurance  that the  terms of the
Offering  will not  change  from  those  described  above.  There can also be no
assurance that the proceeds if any, from the Offering will be used in the manner
described above.  The amounts actually  expended by the Company and the purposes
of such  expenditures may vary  significantly  depending upon numerous  factors,
including the progress of the Company's research, drug discovery and development
programs,  the results of preclinical studies and clinical trials, the timing of
regulatory  approvals,  sales of DNA  products  and  reagents  to third  parties
manufactured  on a custom  contract  basis by the  Hybridon  Specialty  Products
Division and margins on such sales, technological advances, determinations as to
the  commercial   potential  of  the  Company's  compounds  and  the  status  of
competitive  products.  In  addition,  expenditures  will also  depend  upon the
establishment of collaborative  research arrangements with other companies,  the
availability of other financing and other factors.  The Company intends that all
forward-looking  statements  contained  in this press  release be subject to the
safe harbor provisions of the Private Securities  Litigation Reform Act of 1995.
These forward-looking statements reflect the Company's views as of the date they
are made with  respect  to future  events,  but are  subject  to many  risks and
uncertainties,  which  could  cause the actual  results of the Company to differ
materially from any future results expressed or implied by such forward- looking
statements.  The  Company  does not  undertake  to  update  any  forward-looking
statements.