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HYBRIDON, INC.
620 Memorial Drive
Cambridge, MA 02139
August 8, 1997
Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549
Re: Registration Statement on Form S-3 (Registration No. 333-28409)
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Ladies and Gentlemen:
Pursuant to Rule 477 under the Securities Act of 1933, as amended,
Hybridon, Inc. ("Hybridon") hereby withdraws Post-Effective Amendment No. 1 (the
"Post-Effective Amendment") to its Registration Statement on Form S-3
(Registration No. 333-28409) (the "Registration Statement"), which
Post-Effective Amendment was filed on July 25, 1997. Hybridon is withdrawing the
Post-Effective Amendment because it does not wish to remove from registration
the shares of its Common Stock registered under the Registration Statement.
If you have any questions with respect to this letter, please call Stuart
M. Falber, Esquire of the law firm Hale and Dorr LLP at (617) 526-6663.
Very truly yours,
HYBRIDON, INC.
/s/ E. Andrews Grinstead, III
By: ________________________________
E. Andrews Grinstead, III
Chairman of the Board, President
and Chief Executive Officer
EAG:h&d
cc: Roland St. Paul, Esq.
David E. Redlick, Esq.
Stuart M. Falber, Esq.