WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE. <ARTICLE> 5 <CIK> 0001010915 <NAME> MICROCIDE PHARMACEUTICALS, INC. <MULTIPLIER> 1,000 <CURRENCY> U.S. DOLLARS <PERIOD-TYPE> QTR-3 <FISCAL-YEAR-END> DEC-31-1999 <PERIOD-START> JUL-1-1999 <PERIOD-END> SEP-30-1999 <EXCHANGE-RATE> 1 <CASH> 8,483 <SECURITIES> 15,181 <RECEIVABLES> 754 <ALLOWANCES> 0 <INVENTORY> 0 <CURRENT-ASSETS> 25,389 <PP&E> 19,843 <DEPRECIATION> (11,665) <TOTAL-ASSETS> 34,479 <CURRENT-LIABILITIES> 3,600 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 67,003 <OTHER-SE> (38,287) <TOTAL-LIABILITY-AND-EQUITY> 34,479 <SALES> 0 <TOTAL-REVENUES> 1,592 <CGS> 0 <TOTAL-COSTS> 5,147 <OTHER-EXPENSES> 0 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 82 <INCOME-PRETAX> (3,294) <INCOME-TAX> 0 <INCOME-CONTINUING> (3,294) <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> (3,294) <EPS-BASIC> (0.30) <EPS-DILUTED> (0.30)