<ARTICLE> 5 <LEGEND> THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE CONDENSED FINANCIAL STATEMENTS OF T CELL SCIENCES, INC. FOR THE NINE MONTHS ENDED SEPTEMBER 30, 1997 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS. </LEGEND> <CURRENCY> U.S. DOLLARS <PERIOD-TYPE> 9-MOS <FISCAL-YEAR-END> DEC-31-1997 <PERIOD-START> JAN-1-1997 <PERIOD-END> SEP-30-1997 <EXCHANGE-RATE> 1 <CASH> 8,538,000 <SECURITIES> 0 <RECEIVABLES> 19,400 <ALLOWANCES> 0 <INVENTORY> 5,200 <CURRENT-ASSETS> 9,037,300 <PP&E> 3,096,700 <DEPRECIATION> (2,692,800) <TOTAL-ASSETS> 11,503,500 <CURRENT-LIABILITIES> 2,268,200 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 25,000 <OTHER-SE> 7,710,300 <TOTAL-LIABILITY-AND-EQUITY> 11,503,500 <SALES> 36,200 <TOTAL-REVENUES> 840,100 <CGS> 17,200 <TOTAL-COSTS> 6,813,200 <OTHER-EXPENSES> 6,127,000 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> (470,700) <INCOME-PRETAX> (11,646,600) <INCOME-TAX> 0 <INCOME-CONTINUING> (11,646,600) <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> (11,646,600) <EPS-PRIMARY> (0.47) <EPS-DILUTED> (0.47)