<ARTICLE> 5 <LEGEND> THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE FINANCIAL STATEMENTS OF ARONEX PHARMACEUTICALS, INC. SET FORTH IN THE COMPANY'S FORM 10-Q FOR THE NINE MONTHS ENDED SEPTEMBER 30, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS. </LEGEND> <MULTIPLIER> 1 <PERIOD-TYPE> 9-MOS <FISCAL-YEAR-END> DEC-31-1998 <PERIOD-END> SEP-30-1998 <CASH> 3,791,000 <SECURITIES> 12,224,000 <RECEIVABLES> 0 <ALLOWANCES> 0 <INVENTORY> 0 <CURRENT-ASSETS> 15,111,000 <PP&E> 4,904,000 <DEPRECIATION> 2,781,000 <TOTAL-ASSETS> 18,522,000 <CURRENT-LIABILITIES> 6,122,000 <BONDS> 0 <COMMON> 15,000 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <OTHER-SE> 11,338,000 <TOTAL-LIABILITY-AND-EQUITY> 18,522,000 <SALES> 1,342,000 <TOTAL-REVENUES> 0 <CGS> 0 <TOTAL-COSTS> 17,888,000 <OTHER-EXPENSES> 0 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 41,000 <INCOME-PRETAX> (16,546,000) <INCOME-TAX> 0 <INCOME-CONTINUING> (16,546,000) <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> (16,546,000) <EPS-PRIMARY> (1.07) <EPS-DILUTED> (1.07)