FORM 4

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

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* Conlon, Paul J.	2. Issuer Name and Ticker or Trading Symbol NBIX/Neurocrine Biosciences, Inc.		6. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) Vice President Research (Biology)
(Last) (First) (Middle) 10555 Science Center Drive	3. I.R.S. Identification Number of Reporting Person, if an entity (voluntary)	4. Statement for Month/Day/Year 2/6/03
(Street) San Diego, CA 92121		5. If Amendment, Date of Original (Month/Day/Year)	7. Individual or Joint/Group Filing (Check Applicable Line) X Form filed by One Reporting Person Form filed by More than One Reporting Person
(City) (State) (Zip)	Table I — Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1. Title of Security (Instr. 3)	2. Trans- action Date (Month/ Day/ Year)	2A. Deemed Execution Date, if any (Month/Day/ Year)	3. Trans- action Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 & 5)			5. Amount of Securities Beneficially Owned Follow- ing Reported Transactions(s) (Instr. 3 & 4)	6. Owner- ship Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Security (Instr. 3)	2. Trans- action Date (Month/ Day/ Year)	2A. Deemed Execution Date, if any (Month/Day/ Year)	Code	V	Amount	(A) or (D)	Price		6. Owner- ship Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	02/06/03		A⁽³⁾	V	13,357	A	8.625	13,357	I	(Footnote 3)
Common Stock	02/06/03		D⁽⁴⁾	V	3,023	D	8.625		I	(Footnote 4)
Common Stock	02/06/03		A	V	207	A	24.33	207	I	(Footnote 3)
Common Stock	02/06/03		D⁽⁴⁾	V	132	D	24.33		I	(Footnote 4)
Common Stock	02/06/03		D	V	500	D	38.46		I	(Footnote 4)
Common Stock	02/06/03		D	V	500	D	38.55		I	(Footnote 4)
Common Stock	02/06		D	V	4,000	D	38.50		I	(Footnote 4)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

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FORM 4 (continued)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security

(Instr. 3)

2. Conver-
sion or
Exercise
Price of Derivative Security

3. Trans-
action Date

(Month/
Day/
Year)

3A. Deemed
Execution
Date,
if any
(Month/
Day/
Year)

4. Trans-
action
Code

(Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D)

(Instr. 3, 4 & 5)

6. Date Exercisable
and Expiration
Date
(Month/Day/
Year)

7. Title and Amount of Underlying Securities
(Instr. 3 & 4)

8. Price of Derivative Security
(Instr. 5)

9. Number of
Derivative
Securities
Beneficially
Owned
Following
Reported Transaction(s)
(Instr. 4)

10. Owner-
ship Form
of Deriv-
ative
Security:
Direct (D)
or Indirect (I)
(Instr. 4)

11. Nature of Indirect Beneficial Ownership
(Instr. 4)

Code

(A)

(D)

Date Exer-cisable

Expira-
tion
Date

Title

Amount or Number of
Shares

Non-statutory Stock Option

8.625

02/06/03

X⁽¹⁾

13,357

05/10/97

04/10/07

Common Stock

13,357

(Note 1)

Non-statutory Stock Option

24.33

02/06/03

X⁽²⁾

207

05/18/01

04/18/11

Common Stock

207

(Note 2)

Explanation of Responses:

(1) Exercise of in-the-money derivative security held by PDC Limited Liability Company
(2) Exercise of in-the-money derivative security held by PDC Limited Liability Company
(3) Holdings of 02/06/03 exercise of underlying derivative securities held in PDC Limited Liability Company reported in Table II.
(4) Sale of non-derivative securities held in PDC Limited Liability Company

By: /s/ Margaret E. Valeur-Jensen

**Signature of Reporting Person

2/10/03
Date

**Intentional misstatements or omissions of facts constitute Federal Criminal Violations.
See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed.
If space is insufficient, See Instruction 6 for procedure.

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CONLON PAUL J 4