<ARTICLE> 5 <LEGEND> THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE CONDENSED FINANCIAL STATEMENTS OF AVANT IMMUNOTHERAPEUTICS, INC. FOR THE THREE MONTHS ENDED MARCH 31, 1999 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS. </LEGEND> <PERIOD-TYPE> 3-MOS <FISCAL-YEAR-END> DEC-31-1999 <PERIOD-START> JAN-01-1999 <PERIOD-END> MAR-31-1999 <CASH> 10,983,100 <SECURITIES> 0 <RECEIVABLES> 3,800 <ALLOWANCES> (6,000) <INVENTORY> 0 <CURRENT-ASSETS> 12,764,200 <PP&E> 4,503,800 <DEPRECIATION> (3,025,400) <TOTAL-ASSETS> 19,677,300 <CURRENT-LIABILITIES> 3,118,700 <BONDS> 0 <PREFERRED-MANDATORY> 42,500 <PREFERRED> 0 <COMMON> 0 <OTHER-SE> 16,002,100 <TOTAL-LIABILITY-AND-EQUITY> 19,677,300 <SALES> 0 <TOTAL-REVENUES> 337,900 <CGS> 0 <TOTAL-COSTS> 0 <OTHER-EXPENSES> 3,270,700 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> (191,000) <INCOME-PRETAX> (2,741,800) <INCOME-TAX> 0 <INCOME-CONTINUING> (2,741,800) <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> (1,415,500) <EPS-PRIMARY> (0.06) <EPS-DILUTED> (0.06)