<ARTICLE> 5 <LEGEND> THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM GELTEX PHARMACEUTICALS, INC. FINANCIAL STATEMENTS AND THE NOTES THERETO FOR THE YEAR ENDED DECEMBER 31, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS. </LEGEND> <MULTIPLIER> 1 <CURRENCY> U.S. DOLLARS <PERIOD-TYPE> YEAR <FISCAL-YEAR-END> DEC-31-1998 <PERIOD-START> JAN-01-1998 <PERIOD-END> DEC-31-1998 <EXCHANGE-RATE> 1 <CASH> 30,874,900 <SECURITIES> 74,077,436 <RECEIVABLES> 0 <ALLOWANCES> 0 <INVENTORY> 0 <CURRENT-ASSETS> 119,040,047 <PP&E> 11,319,885 <DEPRECIATION> (3,420,415) <TOTAL-ASSETS> 133,444,785 <CURRENT-LIABILITIES> 8,218,742 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 167,924 <OTHER-SE> 119,851,939 <TOTAL-LIABILITY-AND-EQUITY> 133,444,785 <SALES> 0 <TOTAL-REVENUES> 32,658,232 <CGS> 0 <TOTAL-COSTS> 41,145,657 <OTHER-EXPENSES> 0 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 613,513 <INCOME-PRETAX> (11,567,318) <INCOME-TAX> 0 <INCOME-CONTINUING> 0 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> (11,567,318) <EPS-PRIMARY> (.72) <EPS-DILUTED> (.72)