SEC FORM 4

SEC Form 4

FORM 4

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

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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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).

1. Name and Address of Reporting Person^*

CAVAZZA CLAUDIO

(Last)

(First)

(Middle)

VIA SUDAFRICA 20

(Street)

ROME ITALY

00000

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
REGENERX BIOPHARMACEUTICALS INC [ RGN ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
06/11/2003

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	06/11/2003		P		3,184,713	A	$0.628	7,440,032	I⁽¹⁾	I⁽¹⁾
Common Stock	01/23/2004		P		1,052,632	A	$0.95	8,492,664	I⁽¹⁾	I⁽¹⁾
Common Stock	09/03/2004		X		1,382,488	A	$1.085	9,875,152	I⁽¹⁾	I⁽¹⁾
Common Stock	01/07/2005		P		984,615	A	$3.25	984,615	I⁽²⁾	I⁽²⁾
Common Stock	06/22/2005		P		307,692⁽³⁾	A	$3.25	10,182,844	I⁽⁴⁾	I⁽⁴⁾
Common Stock	06/22/2005		P		307,692	A	$3.25	307,692	I⁽⁵⁾	I⁽⁵⁾

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. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Warrant	$1	06/11/2003		J⁽⁶⁾		1		06/11/2003	12/11/2004	Common Stock	750,000	$0⁽¹²⁾	1	I⁽¹⁾	I⁽¹⁾
Warrant	$1.5	01/23/2004		J⁽⁷⁾		1		⁽¹¹⁾	07/23/2006	Common Stock	263,157	$0⁽¹²⁾	1	I⁽¹⁾	I⁽¹⁾
Warrant	$1.25	01/23/2004		J⁽⁸⁾		1		12/11/2003	12/11/2004	Common Stock	600,000	$0⁽¹²⁾	1	I⁽¹⁾	I⁽¹⁾
Warrant	$1.085	09/02/2004		J⁽⁹⁾		2		⁽¹¹⁾	⁽⁹⁾	Common Stock	1,382,488	$0⁽¹²⁾	2	I⁽¹⁾	I⁽¹⁾
Warrant	$1.085	09/03/2004		X			2	⁽¹¹⁾	⁽⁹⁾	Common Stock	1,382,488	$0⁽¹²⁾	0	I⁽¹⁾	I⁽¹⁾
Warrant	$4.06	01/07/2005		J⁽¹⁰⁾		1		⁽¹¹⁾	01/07/2008	Common Stock	246,154	$0⁽¹²⁾	1	I⁽²⁾	I⁽²⁾

Explanation of Responses:

1. Securities directly owned by Defiante Farmaceutica, L.D.A. ("Defiante"). Defiante is 58% directly owned by Sigma Tau Finanzaria S.p.A. ("Sigma Tau") and 42% directly owned by Sigma Tau's wholly-owned subsidiary, Sigma Tau International S.A. Claudio Cavazza directly and indirectly owns 60% of Sigma Tau. The securities were previously reported on Form 4 by Sigma Tau and Defiante.

2. Securities directly owned, and previously reported on Form 4, by Sigma Tau.

3. These shares were acquired pursuant to a purchase agreement with the issuer that provides that the Reporting Person may not dispose of the shares for a five-year period (the "Holding Period"), that the issuer, rather than the Reporting Person, has all voting rights in respect of the shares during the Holding Period, and that the issuer shall have the right to repurchase the shares within 30 days of the expiration of the Holding Period at a price of $5.00 per share, provided that the issuer may only repurchase an amount of shares that would leave the Reporting Person, when combined with all of its affiliates, with no less than 30.1% of the Issuer's shares of Common Stock.

4. Shares directly owned by Defiante.

5. Shares directly owned by Inverlochy Consultadora & Servicos L.d.a.("Inverlochy"). Claudio Cavazza indirectly owns 100% of Inverlochy.

6. The Warrant was issued by the Issuer to Defiante in consideration of Defiante's purchase of Common Stock. Previously reported on Form 4 by Defiante and Sigma Tau.

7. The Warrant was issued by the Issuer on 1/23/04 to Defiante in consideration of Defiante's purchase of Common Stock. Previously reported on Form 4 by Defiante and Sigma Tau.

8. The Warrant was issued by the Issuer on 6/11/03 to Defiante in consideration of Defiante's purchase of Common Stock, but the exercise price and the number of shares issuable upon exercise of the Warrant did not become fixed until 1/23/04. Previously reported on Form 4 by Defiante and Sigma Tau.

9. Represents Warrants that were acquired on June 11, 2003. The Warrants were initially exercisable for a total of 1,350,000 shares of common stock at an average exercise price of $1.111 and had an expiration date of 12/11/04. An amendment to the terms of the Warrants dated September 2, 2004 provided that, if the holder exercised the Warrants by not later than September 6, 2004, the Warrants would be exercisable for a total of 1,382,488 shares of common stock at an exercise price of $1.085 per share. Previously reported on Form 4 by Defiante and Sigma Tau.

10. The Warrant was issued by the Issuer to Sigma Tau in consideration of Sigma Tau's purchase of Common Stock.

11. Immediately.

12. N/A.

	/s/ Maurizio Terenzi, Attorney-In-Fact	06/24/2005
	** Signature of Reporting Person	Date
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