EXHIBIT 99.1

Contact: MaryBeth Alvin
         610/738-6376
         malvin@cephalon.com

FOR IMMEDIATE RELEASE

              CEPHALON ANNOUNCES A PRIVATE OFFERING OF CONVERTIBLE
                               SUBORDINATED NOTES
                               ------------------


WEST CHESTER, PA, May 2, 2001 -- Cephalon, Inc. (NASDAQ: CEPH) today announced
the private placement of $300 million of its 5.25% Convertible Subordinated
Notes due 2006. This offering, which was made through initial purchasers to
qualified institutional buyers under Rule 144A of the Securities Act of 1933, as
amended (the "Securities Act"), is expected to close on May 7, 2001.

Cephalon has granted the initial purchasers a 45-day option to purchase an
additional $100 million in aggregate principal amount of notes. The notes are
convertible into Cephalon's common stock at a conversion price of $74.00 per
share, subject to adjustment in certain circumstances. Cephalon has agreed to
file a registration statement for the resale of the notes and common stock
issuable upon conversion of the notes within 45 days after the closing of the
offering.

Cephalon expects to use the net proceeds of the offering for working capital and
general corporate purposes, which may include the acquisition of businesses,
products, product rights or technologies. Additionally, Cephalon may also use
the net proceeds to pay contractual obligations including those incurred in
connection with the previously announced Abbott and Novartis transactions.

This press release does not constitute an offer to sell or the solicitation of
an offer to buy any of these securities, nor will there be any sale of the notes
in any state in which such offer, solicitation or sale would be unlawful prior
to registration or qualification under the securities laws of any such state.

The notes and the common stock issuable upon conversion of the notes have not
been registered under the Securities Act, or any state securities laws, and are
being offered and sold through initial purchasers to qualified institutional
buyers in reliance on Rule 144A under the Securities Act. Unless so registered,
the notes and the common stock issuable upon conversion of the notes may not be
offered or sold in the United States except pursuant to an exemption from, or in
a transaction not subject to, the registration requirements of the Securities
Act and applicable states securities laws.

Cephalon, Inc., headquartered in West Chester, Pennsylvania, is an
international biopharmaceutical company dedicated to the discovery, development
and marketing of products to treat sleep disorders, neurological disorders,
cancer and pain.





IN ADDITION TO HISTORICAL FACTS OR STATEMENTS OF CURRENT CONDITION, THIS PRESS
RELEASE MAY CONTAIN FORWARD-LOOKING STATEMENTS. FORWARD-LOOKING STATEMENTS
PROVIDE CEPHALON'S CURRENT EXPECTATIONS OR FORECASTS OF FUTURE EVENTS. THESE MAY
INCLUDE STATEMENTS REGARDING THE CLOSING OF THE OFFERING OF THE NOTES, INCLUDING
THE DATE THEREOF, CEPHALON'S USE OF THE NET PROCEEDS FROM THE OFFERING, AND
OTHER STATEMENTS REGARDING MATTERS THAT ARE NOT HISTORICAL FACTS. YOU MAY
IDENTIFY SOME OF THESE FORWARD-LOOKING STATEMENTS BY THE USE OF WORDS IN THE
STATEMENTS SUCH AS "EXPECT," OR OTHER WORDS AND TERMS OF SIMILAR MEANING.
CEPHALON'S PERFORMANCE AND FINANCIAL RESULTS COULD DIFFER MATERIALLY FROM THOSE
REFLECTED IN THESE FORWARD-LOOKING STATEMENTS DUE TO GENERAL FINANCIAL,
ECONOMIC, REGULATORY AND POLITICAL CONDITIONS AFFECTING THE BIOTECHNOLOGY AND
PHARMACEUTICAL INDUSTRIES AS WELL AS MORE SPECIFIC RISKS AND UNCERTAINTIES SUCH
AS THOSE SET FORTH IN ITS REPORTS ON FORM 8-K, 10-Q AND 10-K FILED WITH THE U.S.
SECURITIES AND EXCHANGE COMMISSION. GIVEN THESE RISKS AND UNCERTAINTIES, ANY OR
ALL OF THESE FORWARD-LOOKING STATEMENTS MAY PROVE TO BE INCORRECT. THEREFORE,
YOU SHOULD NOT RELY ON ANY SUCH FACTORS OR FORWARD-LOOKING STATEMENTS.
FURTHERMORE, CEPHALON DOES NOT INTEND (AND IT IS NOT OBLIGATED) TO UPDATE
PUBLICLY ANY FORWARD-LOOKING STATEMENTS. THIS DISCUSSION IS PERMITTED BY THE
PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995.


NOTE: Cephalon's press releases are posted on the Internet at the company's Web
site at http://www.cephalon.com. They are also available by fax 24 hours a day
at no charge by calling PR Newswire's Company News On-Call at 800-758-5804,
extension 134563.