8-K

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                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                              ---------------------
                                    FORM 8-K
                                 CURRENT REPORT
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     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

       Date of Report (Date of the earliest event reported): April 5, 2000


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

      CALIFORNIA                   0-28150                     33-0525145
    (State or other         (Commission File Number)         (IRS Employer
    jurisdiction of                                       Identification Number)
     incorporation)

   10555 Science Center Drive, San Diego, CA                         92121
   (Address of principal executive offices)                        (Zip Code)

       Registrant's telephone number, including area code: (858) 658-7600



                                       N/A
         (Former name or former address, if changed since last report.)

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ITEM 5.  OTHER EVENTS

     On April 5, 2000,  Neurocrine  Biosciences,  Inc.  announced  that  Janssen
Pharmaceutica, N.V. intends to substitute its lead CRF antagonist (R121919) with
a  Neurocrine/Janssen  back-up  compound  resulting  from the expanded  research
collaboration  entered into during 1999.  The  decision to  discontinue  further
development  of R121919 was based on  observations  of  reversible  increases in
liver  enzymes in two  volunteers  participating  in an  expanded  safety  trial
conducted in the United  Kingdom.  Approximately  250 subjects to date have been
treated  in  various  clinical  trials  with no other  observed  safety  issues.

     A copy of the  press  release  issued  by the  Registrant  on April 5, 2000
concerning the foregoing transactions are filed herewith as Exhibits 99.1 and is
incorporated herein by reference.



ITEM 7. FINANCIAL STATEMENTS, PRO-FORMA FINANCIAL INFORMATION  AND EXHIBITS

(a)      FINANCIAL STATEMENTS OF BUSINESS ACQUIRED. Not applicable.

(b)      PRO-FORMA FINANCIAL INFORMATION. Not applicable.

(c)      EXHIBITS.   The following exhibits are filed herewith:

         99.1       Press  Release of Registrant, dated April 5, 2000,
                    announcing Janssen Pharmaceutica's  replacement of R121919
                    with a back-up compound



                                   SIGNATURES

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


Dated:   04/05/00          By:/s/ Paul W. Hawran
         --------             ------------------
                              Paul W. Hawran
                              Senior Vice President and Chief Financial Officer
                             (Principal Financial and Accounting Officer)




                                  EXHIBIT INDEX

Exhibit Number      Description
- ------------------- ------------------------------------------------------------
  99.1              Press Release of Registrant, dated April 5, 2000, announcing
                    Janssen Pharmaceutica's   replacement  of  R121919  with  a
                    back-up compound

EX-99

                                                                    EXHIBIT 99.1

FOR IMMEDIATE RELEASE:
Contact at Neurocrine Biosciences:
Claudia Jones or Paul Hawran
(858) 658-7600



       NEUROCRINE ANNOUNCES THAT JANSSEN PHARMACEUTICA INTENDS TO REPLACE
                        R121919 WITH A BACK-UP COMPOUND

    NEUROCRINE CRF PROGRAM ON TRACK FOR PHASE I TRIALS TO BEGIN 2ND HALF 2000
        WITH UNPARTNERED CRF ANTAGONIST COMPOUND FOR ANXIETY/DEPRESSION

San Diego,  CA,  April 5, 2000 - Neurocrine  Biosciences,  Inc.  (Nasdaq:  NBIX)
announced  today that Janssen  Pharmaceutica  intends to substitute its lead CRF
antagonist (R121919) with a  Neurocrine/Janssen  back-up compound resulting from
the expanded research collaboration entered in 1999. The decision to discontinue
further development of R121919 was based on observations of reversible increases
in liver enzymes in two  volunteers  participating  in an expanded  safety trial
conducted in the United  Kingdom.  Approximately  250 subjects to date have been
treated  in  various  clinical  trials  with no other  observed  safety  issues.
Separately, Neurocrine also confirmed that Phase I clinical trials are scheduled
to begin in the 2nd half of 2000 for its unpartnered CRF antagonist compound for
anxiety/depression.

"Janssen remains committed to the CRF technology.  This technology  continues to
be  important  to us," said  Rolondo  Gutierrez,  M.D.,  Global  Product  Leader
Antidepressants  and  Anxiolytics of Janssen  Pharmaceutica.  "We have learned a
great deal about the CRF mechanism from our preclinical and clinical  experience
with this  compound.  We believe this  knowledge  will help us to accelerate the
clinical development of future potential CRF antagonist compounds."

"Recently,  considerable  evidence from preclinical and clinical  investigations
have provided  even more support for the CRF  hypothesis  of  depression,"  said
Charles  Nemeroff,  M.D.,  Ph.D.,  Chairman and  Professor of the  Department of
Psychiatry and Behavioral Sciences at Emory University School of Medicine.  "One
piece of this expanding database is the promising results with the CRF1 receptor
antagonist,  R121919.  This safety  issue  which  appears  unrelated  to the CRF
receptor mechanism  unfortunately precludes further clinical development of this
compound.    I   have    little    doubt    that    this    novel    class    of
antidepressants/anxiolytics  will represent a  breakthrough  in the treatment of
these devastating disorders."

Neurocrine also confirmed today that the clinical development of its unpartnered
CRF  antagonist  compound  for  anxiety/depression  is  scheduled to begin human
clinical trials in the 2nd half 2000. This proprietary  compound is from a novel
chemical series which is distinct from R121919. Based on preclinical studies the
Neurocrine  proprietary  compound  has  demonstrated  improved  specificity  and
greater potency together with excellent pharmacokinetic properties.

"The  results of an  unrelated  open label Phase IIa study  conducted at the Max
Planck Institute have provided encouraging results regarding the validity of the
CRF  mechanism as a potential  therapeutic  target for anxiety and  depression,"
said Florian Holsboer, M.D., Ph.D., and Director at the Max Planck Institute fur
Psychiatrie in Munich, Germany. "There is no indication of a causal relationship
between the  pharmacology  of the  compound  and the safety  concerns  that have
arisen  by the  two  volunteers  in the  expanded  safety  study  in the  United
Kingdom."

"While we are disappointed by these developments, the Janssen work has generated
valuable knowledge with respect to the CRF mechanism which will guide our future
development," said Gary Lyons,  President & CEO. "In addition to our unpartnered
CRF program,  our  expanded  collaboration  with  Janssen has produced  multiple
back-up  compounds  from which the next  series of clinical  candidates  will be
selected.  We look forward to continuing and perhaps expanding our collaboration
with Janssen in this field."

CRF was first identified and cloned by Neurocrine co-founder, Dr. Wylie Vale and
his colleagues at the Salk Institute.  Neurocrine holds the patent rights to the
CRF family of receptors and has developed multiple series of selective,  potent,
small   molecule   antagonists   for  these   receptors.   CRF  functions  as  a
neurotransmitter  in the brain and plays a  critical  role in  coordinating  the
body's  responses to stress.  The CRF1 receptor  subtype largely  mediates these
effects. In preclinical models, selective CRF1 receptor antagonists block stress
responses  providing  evidence that this novel  mechanism may result in improved
anti-anxiety and anti-depressant drugs. CRF1 antagonists have not shown evidence
of  sexual  dysfunction  or  addictive  properties  in  preclinical  models.  In
addition, some data suggest that CRF1 antagonists may have a more rapid onset of
action compared to the currently marketed anti-depressants.

Including  R121919,  Neurocrine  has now advanced  five  programs  into clinical
trials.  Neurocrine  is conducting  several  Phase II trials with  NBI-34060 for
insomnia,  a Phase  I/II with NBI 3001 for  glioblastoma  and a Phase I with NBI
6024 with  Altered  Peptide  Ligand for Type I  diabetes.  In  addition,  as the
company has recently announced, Neurocrine is planning a Phase II clinical trial
of its APL compound for multiple  sclerosis  following  positive results from an
earlier Phase II trial.



Neurocrine  Biosciences  is  a  leading  neuroscience  company  focused  on  the
discovery  and   development  of  novel   therapeutics   for   neuropsychiatric,
neuroinflammatory  and neurodegenerative  diseases and disorders.  The Company's
neuroscience,  endocrine and immunology  disciplines provide a unique biological
understanding of the molecular  interaction between central nervous,  immune and
endocrine systems for the development of therapeutic  interventions for anxiety,
depression,  insomnia,  stroke,  malignant  brain  tumors,  multiple  sclerosis,
obesity and diabetes.

Neurocrine  Biosciences,  Inc. news releases are available through the Company's
website via the Internet at http://www.neurocrine.com.
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     In  addition  to   historical   facts,   this  press  release  may  contain
forward-looking  statements  that  involve a number of risks and  uncertainties.
Among the factors  that could cause  actual  results to differ  materially  from
those  indicated in the forward looking  statements are risks and  uncertainties
associated with Neurocrine's CRF antagonist development programs including,  but
not limited to,  risks and  uncertainties  associated  with,  or arising out of,
clinical  development of products  including risk that  development  candidates,
will not  successfully  proceed  through early clinical  trials or that in later
stage clinical trials will not show that they are effective in treating  humans;
determinations  by  regulatory  and  governmental   authorities,   uncertainties
relating to patent protection and intellectual property rights of third parties;
impact of  competitive  products  and  technological  changes;  availability  of
capital  and  cost  of  capital;  and  other  material  risks.  A more  complete
description  of these risks can be found in the Company's  Form 10K for December
31, 1999. Neurocrine undertakes no obligation to update the statements contained
in this press release after the date hereof.

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