<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from Cephalon,
Inc.'s Form 10-Q for the quarter ended June 30, 2000 and is qualified in its
entirety by reference to such financial statements.
</LEGEND>
<CIK> 0000873364
<NAME> CEPHALON, INC.

                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-START>                             JAN-01-2000
<PERIOD-END>                               JUN-30-2000
<CASH>                                      29,010,000
<SECURITIES>                               121,377,000
<RECEIVABLES>                               11,017,000
<ALLOWANCES>                                         0
<INVENTORY>                                 14,465,000
<CURRENT-ASSETS>                           176,895,000
<PP&E>                                      40,369,000
<DEPRECIATION>                              16,030,000
<TOTAL-ASSETS>                             203,687,000
<CURRENT-LIABILITIES>                       29,330,000
<BONDS>                                     13,486,000
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                     25,000
<COMMON>                                       348,000
<OTHER-SE>                                 160,300,000
<TOTAL-LIABILITY-AND-EQUITY>               203,687,000
<SALES>                                     28,750,000
<TOTAL-REVENUES>                            38,006,000
<CGS>                                        5,074,000
<TOTAL-COSTS>                                5,074,000
<OTHER-EXPENSES>                            27,377,000
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                           2,949,000
<INCOME-PRETAX>                           (16,400,000)
<INCOME-TAX>                                         0
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<NET-INCOME>                              (20,931,000)
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