AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON APRIL 25, 2001 REGISTRATION NO. 333-69067 ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 ------------- POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-3 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 TRIANGLE PHARMACEUTICALS, INC. (Exact name of Registrant as Specified in Its Charter) DELAWARE 56-1930728 (State or Other Jurisdiction (I.R.S. Employer of Incorporation or Organization) Identification No.) 4 UNIVERSITY PLACE 4611 UNIVERSITY DRIVE DURHAM, NORTH CAROLINA 27707 (919) 493-5980 (Address, Including Zip Code and Telephone, Including Area Code, of Registrant's Principal Executive Offices) DAVID W. BARRY, M.D. CHAIRMAN AND CHIEF EXECUTIVE OFFICER TRIANGLE PHARMACEUTICALS, INC. 4 UNIVERSITY PLACE, 4611 UNIVERSITY DRIVE DURHAM, NORTH CAROLINA 27707, (919) 493-5980 (Name, Address, Including Zip Code and Telephone Number, Including Area Code, of Agent for Service) Copies To: RACHEL MANDELL, ESQ. TRIANGLE PHARMACEUTICALS, INC. 4 UNIVERSITY PLACE, 4611 UNIVERSITY DRIVE DURHAM, NORTH CAROLINA 27707, (919) 493-5980 ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- DEREGISTRATION OF SHARES Triangle Pharmaceuticals is filing this post effective amendment to deregister, as of the date hereof, 1,822,730 shares of Triangle Pharmaceuticals' common stock remaining unsold at the conclusion of the offering described in the registration statement on Form S-3 (Reg. No. 333-69067). The shares were being offered by selling stockholders of Triangle Pharmaceuticals. SIGNATURES Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Durham, State of North Carolina, on April 25, 2001. TRIANGLE PHARMACEUTICALS, INC. By: /s/ David W. Barry -------------------------------- David W. Barry CHAIRMAN AND CHIEF EXECUTIVE OFFICER Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated: SIGNATURE TITLE --------------------------------- -------------------------- Chairman of the Board and /s/ David W. Barry Chief Executive Officer ---------------------------------- (Principal Executive Officer) April 25, 2001 David W. Barry /s/ Chris A. Rallis Director, President and Chief Operating ----------------------------------- Officer April 25, 2001 Chris A. Rallis Executive Vice President and Chief /s/ Robert F. Amundsen, Jr. Financial Officer ----------------------------------- (Principal Financial April 25, 2001 Robert F. Amundsen, Jr. and Accounting Officer) * ----------------------------------- Director April 25, 2001 Anthony B. Evnin * ----------------------------------- Director April 25, 2001 Standish M. Fleming * ------------------------------------ Director April 25, 2001 Dennis B. Gillings * ------------------------------------ Director April 25, 2001 Henry G. Grabowski * ------------------------------------ Director April 25, 2001 George McFadden *By: /s/ David W. Barry ------------------------------------- David W. Barry ATTORNEY-IN-FACT