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

                               December 20, 2001
                Date of Report (Date of earliest event reported)


                              NEUROGEN CORPORATION
             (Exact name of registrant as specified in its charter)


              Delaware                 0-18311               22-2845714
   (State or other jurisdiction of    (Commission            (I.R.S. Employer
   incorporation or organization)     File Number)           Identification No.)


                          35 Northeast Industrial Road
                           Branford, Connecticut 06405
               (Address of principal executive offices) (Zip Code)


                                 (203) 488-8201
              (Registrant's telephone number, including area code)

None
(Former name or former address, if changed since last report)


Item 5. Other Events

     On December 20, 2001, Neurogen Corporation  ("Neurogen") and Aventis Pharma
("Aventis")  jointly announced an exclusive  worldwide  collaboration to develop
new  drugs for  treatment  of  depression,  anxiety,  and  other  stress-related
disorders based on Neurogen's portfolio of pre-clinical corticotrophin releasing
factor (CRF1)  antagonist  compounds.  Aventis Pharma has licensed this class of
compounds,  including  Neurogen's lead candidate NGD 98-2.  Neurogen and Aventis
have also entered into a three to five year research  collaboration  designed to
bring forward additional CRF1 candidates.

     Under the terms of the agreement,  Neurogen  received an initial payment of
$10  million  from  Aventis.  Neurogen  will also be  eligible  to receive  cash
payments based upon the  achievement of certain  milestones in the drug research
and  development  process  if these  milestones  are  achieved.  Also  under the
agreement,  Aventis receives  exclusive  worldwide  development,  manufacturing,
marketing and sales rights to collaborative  compounds which come to market, and
agrees to pay  Neurogen  royalties  on these  sales,  if any.  Aventis will also
assume the full  responsibility  for the  development and  commercialization  of
compounds emerging from this program.

SAFE HARBOR STATEMENT

Statements  which  are not  historical  facts,  including  statements  about the
Company's  confidence and strategies,  the status of various product development
programs,  the sufficiency of cash to fund planned  operations and the Company's
expectations  concerning its development compounds,  drug discovery technologies
and  opportunities  in  the  pharmaceutical  marketplace  are  "forward  looking
statements" within the meaning of the Private Securities  Litigations Reform Act
of 1995 that involve risks and  uncertainties  and are not  guarantees of future
performance. These risks include, but are not limited to, difficulties or delays
in development, testing, regulatory approval, production and marketing of any of
the  Company's  drug  candidates,  the  failure to attract or retain  scientific
management  personnel,   any  unexpected  adverse  side  effects  or  inadequate
therapeutic  efficacy  of the  Company's  drug  candidates  which  could slow or
prevent  product   development   efforts,   competition   within  the  Company's
anticipated product markets, the Company's dependence on corporate partners with
respect  to  research   and   development   funding,   regulatory   filings  and
manufacturing and marketing expertise, the uncertainty of product development in
the pharmaceutical industry, inability to obtain sufficient funds through future
collaborative  arrangements,  equity  or debt  financings  or other  sources  to
continue  the  operation  of the  Company's  business,  risk  that  patents  and
confidentiality   agreements   will  not   adequately   protect  the   Company's
intellectual  property or trade secrets,  dependence  upon third parties for the
manufacture of potential  products,  inexperience in  manufacturing  and lack of
internal  manufacturing  capabilities,  dependence  on third  parties  to market
potential  products,  lack  of  sales  and  marketing  capabilities,   potential
unavailability   or  inadequacy  of  medical   insurance  or  other  third-party
reimbursement  for the cost of purchases of the  Company's  products,  and other
risks  detailed in the Company's  Securities  and Exchange  Commission  filings,
including its Annual Report on Form 10-K and 10-K/A for the year ended  December
31, 2000,  each of which could adversely  affect the Company's  business and the
accuracy of the forward-looking statements contained herein.

                                   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 hereunto duly authorized.

                                                     NEUROGEN CORPORATION
                                              ----------------------------------
                                                          (Registrant)

   December 21, 2001                          /s/ Stephen R. Davis
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          DATE                                 Stephen R. Davis
                             Executive Vice President and Chief Business Officer