1 SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report: September 3, 1997 Commission File No. 0-27352 ----------------- ------- (Date of earliest event reported) HYBRIDON, INC. -------------- (Exact name of registrant as specified in its Charter) Delaware 04-3072298 -------- ---------- (State or other jurisdiction of (IRS Employer Identification No.) incorporation or organization) 620 Memorial Drive, Cambridge, Massachusetts 02139 - -------------------------------------------- ----- (Address of principal executive offices) (Zip Code) (617) 528-7000 -------------- (Registrant's telephone number, including area code) 2 ITEM 5. OTHER EVENTS On September 3, 1997, Hybridon, Inc. (the "Company") issued a press release announcing the termination of its research and development collaboration with F. Hoffmann-LaRoche, Ltd. A copy of the press release has been filed with this Current Report on Form 8-K as Exhibit 99.1 and is incorporated herein by reference. ITEM 7. EXHIBITS 99.1 Press release dated September 3, 1997. 3 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Dated: September 5, 1997 HYBRIDON, INC. /s/ E. Andrews Grinstead, III --------------------------------------- E. Andrews Grinstead, III Chairman, President and Chief Executive Officer 4 INDEX TO EXHIBITS Exhibit No. Description - ------- ----------- 99.1 Press release dated September 3, 1997.