<TABLE> <S> <C>
<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SECTION CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM ORAPHARMA,
INC'S JUNE 30, 2000 FINANCIAL STATEMENT AND IS QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0001028065
<NAME> ORAPHARMA, INC.
<MULTIPLIER> 1
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> JUN-30-2000
<CASH> 82,986,691
<SECURITIES> 0
<RECEIVABLES> 0
<ALLOWANCES> 0
<INVENTORY> 0
<CURRENT-ASSETS> 84,194,386
<PP&E> 1,584,113
<DEPRECIATION> 590,640
<TOTAL-ASSETS> 85,904,661
<CURRENT-LIABILITIES> 1,643,856
<BONDS> 0
0
0
<COMMON> 13,151
<OTHER-SE> 84,247,654
<TOTAL-LIABILITY-AND-EQUITY> 85,904,661
<SALES> 0
<TOTAL-REVENUES> 0
<CGS> 0
<TOTAL-COSTS> 0
<OTHER-EXPENSES> 5,943,050
<LOSS-PROVISION> 0
<INTEREST-EXPENSE> 8,889
<INCOME-PRETAX> (4,324,072)
<INCOME-TAX> 0
<INCOME-CONTINUING> (4,324,072)
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> (4,324,072)
<EPS-BASIC> (0.51)
<EPS-DILUTED> (0.51)
</TABLE>