<PAGE> 1
RULE 424(b)(3) & (c)
REG. NO. 333-24793
PROSPECTUS SUPPLEMENT DATED MAY 9, 1997, TO PROSPECTUS DATED MAY 7, 1997
490,000 Shares
CEPHALON, INC.
COMMON STOCK
RECENT DEVELOPMENT
On May 8, 1997, the Peripheral and Central Nervous System Drugs Advisory
Committee (the "Advisory Committee") of the U.S. Food and Drug Administration
(the "FDA") found, by a vote of 6 to 3, that there was not substantial
evidence that MYOTROPHIN(R) (rhIGF-I) Injection is effective in the treatment of
amyotrophic lateral sclerosis ("ALS" or "Lou Gehrig's disease"). The
Advisory Committee's finding was requested by the FDA in conjunction with its
review of a New Drug Application submitted by Cephalon, Inc. (the "Company")
and Chiron Corp. for clearance to market MYOTROPHIN Injection for the treatment
of ALS.
These statements are included in the Company's Current Report on Form
8-K, dated May 8, 1997, reference to which is added under the caption
"Incorporation of Certain Documents by Reference."
All statements in the Prospectus dated May 7, 1997 (the "Prospectus"),
relating to the Company's new drug application for use of MYOTROPHIN (rhIGF-I)
in treating ALS are modified, and to the extent inconsistent herewith,
superseded by the statements under "Recent Development" in this Prospectus
Supplement.
SELLING STOCKHOLDER
The table under the caption "Selling Stockholder" in the Prospectus is
replaced by the following:
<TABLE>
<CAPTION>
BENEFICIAL OWNERSHIP
AFTER OFFERING
NUMBER OF SHARES -----------------------------------
NAME OF BENEFICIALLY OWNED NUMBER OF SHARES NUMBER OF
SELLING STOCKHOLDER PRIOR TO OFFERING BEING OFFERED SHARES PERCENT
- ------------------- ----------------- ---------------- -------------------- -------
<S> <C> <C> <C> <C>
Swiss Bank Corporation,
London Branch 750,000(1) 490,000 260,000(1) 1%
</TABLE>
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(1) Includes 260,000 shares of Common Stock, which were acquired in the open
market after May 1, 1997, and may be sold from time to time.
