RGRX RegeneRX Biopharmaceuticals Inc (CE)

Item 1 of the Schedule 13D is hereby amended and restated in its entirety as follows:

This Amendment No. 21 by Essetifin S.p.A., an Italian corporation (“ Essetifin ”), Paolo Cavazza, an Italian citizen, Enrico Cavazza, an Italian citizen, Francesca Cavazza, an Italian citizen, Silvia Cavazza, an Italian citizen, and Martina Cavazza Preta, an Italian citizen (together with Essetifin, Paolo Cavazza, Enrico Cavazza, Francesca Cavazza and Silvia Cavazza, the “ Reporting Parties ”), amends the Schedule 13D filed with the Securities and Exchange Commission (the “ SEC ”) on June 23, 2003, as amended by Amendment No. 1 filed with the SEC on January 26, 2004, Amendment No. 2 filed with the SEC on September 9, 2004, Amendment No. 3 filed with the SEC on September 22, 2004, Amendment No. 4 filed with the SEC on January 19, 2005, Amendment No. 5 filed with the SEC on June 24, 2005, Amendment No. 6 filed with the SEC on March 16, 2006, Amendment No. 7 filed with the SEC on July 24, 2006, Amendment No. 8 filed with the SEC on January 3, 2007, Amendment No. 9 filed with the SEC on January 10, 2008, Amendment No. 10 filed with the SEC on March 10, 2008, Amendment No. 11 filed with the SEC on April 4, 2008, Amendment No. 12 filed with the SEC on December 19, 2008, Amendment No. 13 filed with the SEC on April 13, 2009, Amendment No. 14 filed with the SEC on October 19, 2009, Amendment No. 15 filed with the SEC on July 9, 2010, Amendment No. 16 filed with the SEC on January 14, 2011, Amendment No. 17 filed with the SEC on October 25, 2012, Amendment No. 18 filed with the SEC on September 24, 2013, Amendment No. 19 filed with the SEC on October 17, 2017, and Amendment No. 20 filed with the SEC on March 14, 2018 (the “ Schedule 13D ”), with respect to the common stock, $0.001 par value (the “ Common Stock ”), of RegeneRx Biopharmaceuticals, Inc. (the “ Issuer ”), a Delaware corporation whose principal offices are located at 15245 Shady Grove Road, Suite 470, Rockville, MD 20850.

Item 4 of the Schedule 13D is hereby amended by adding the following at the end thereof:

On September 27, 2018, Essetifin exercised its option to convert the Convertible Promissory Note, originally issued on September 11, 2013 and reissued on March 13, 2018, by the Issuer to Essetifin in an initial principal amount of $150,000 (the “ Note ”), including all accrued but unpaid interest thereon, into shares of Common Stock at a conversion price of $0.06 per share of Common Stock. As a result of the such conversion and as of September 27, 2018, Essetifin directly owns 34,989,080 shares of Common Stock, which includes 3,133,681 shares of Common Stock that were issued upon conversion the Note.

Item 5 of the Schedule 13D is hereby amended and restated in its entirety as follows:

(a) As of September 27, 2018, Essetifin is the beneficial owner of 34,989,080 shares of Common Stock representing 28.7% of the Issuer’s outstanding Common Stock, based on 121,726,402 shares of Common Stock outstanding as of August 7, 2018, as reported in the Issuer’s Form 10-Q filed with the SEC on August 9, 2018.

As of September 27, 2018, each of Paolo Cavazza, Enrico Cavazza, Francesca Cavazza, Silvia Cavazza and Martina Cavazza Preta is the beneficial owner of 34,989,080 shares of Common Stock representing 28.7% of the Issuer’s outstanding Common Stock, based on 121,726,402 shares of Common Stock outstanding as of August 7, 2018, as reported in the Issuer’s Form 10-Q filed with the SEC on August 9, 2018.

(b) The number of shares of Common Stock as to which Essetifin has the sole power to vote or direct the vote is zero. The number of shares of Common Stock as to which Essetifin shares the power to vote or direct the vote is 34,989,080. The number of shares of Common Stock as to which Essetifin has the sole power to dispose or direct the disposition is zero. The number of shares of Common Stock as to which Essetifin shares the power to dispose or direct the disposition is 34,989,080.

The number of shares of Common Stock as to which each of Paolo Cavazza, Enrico Cavazza, Francesca Cavazza, Silvia Cavazza and Martina Cavazza Preta has the sole power to vote or direct the vote is zero. The number of shares of Common Stock as to which each of Paolo Cavazza, Enrico Cavazza, Francesca Cavazza, Silvia Cavazza and Martina Cavazza Preta shares the power to vote or direct the vote is 34,989,080. The number of shares of Common Stock as to which each of Paolo Cavazza, Enrico Cavazza, Francesca Cavazza, Silvia Cavazza and Martina Cavazza Preta has the sole power to dispose or direct the disposition is zero. The number of shares of Common Stock as to which each of Paolo Cavazza, Enrico Cavazza, Francesca Cavazza, Silvia Cavazza and Martina Cavazza Preta shares the power to dispose or direct the disposition is 34,989,080.

(c) See Item 4 above.

(d) Not applicable.

(e) Not applicable.

*****

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement with respect to Essetifin S.p.A. is true, complete and correct.

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement with respect to Paolo Cavazza is true, complete and correct.

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement with respect to Enrico Cavazza is true, complete and correct.

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement with respect to Francesca Cavazza is true, complete and correct.

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement with respect to Silvia Cavazza is true, complete and correct.

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement with respect to Martina Cavazza Preta is true, complete and correct.

** Power of attorney was previously filed with Securities and Exchange Commission as an exhibit to the Form 3/A filed on October 4, 2017, with respect to the common stock of Fennec Pharmaceuticals, Inc.

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