<ARTICLE> 5
<LEGEND> This schedule contains summary financial information extracted from 
the unaudited consolidated financial statements of PathoGenesis Corporation for 
the three months ended March 31, 1998, and is qualified in its entirety by 
reference to such financial statements. 
</LEGEND>
       
                             
<PERIOD-TYPE>                   3-MOS
<FISCAL-YEAR-END>                         DEC-31-1998
<PERIOD-START>                            JAN-01-1998
<PERIOD-END>                              MAR-31-1998
<CASH>                                      1,467,265
<SECURITIES>                               66,313,271         
<RECEIVABLES>                              11,318,597
<ALLOWANCES>                                        0<F1>
<INVENTORY>                                 6,070,696
<CURRENT-ASSETS>                           86,291,267 
<PP&E>                                     18,083,173
<DEPRECIATION>                              7,759,331
<TOTAL-ASSETS>                             97,403,523
<CURRENT-LIABILITIES>                       6,683,692
<BONDS>                                             0
<PREFERRED-MANDATORY>                               0
<PREFERRED>                                         0
<COMMON>                                       16,246
<OTHER-SE>                                191,707,694
<TOTAL-LIABILITY-AND-EQUITY>               97,403,523
<SALES>                                    14,527,031 
<TOTAL-REVENUES>                           14,664,897
<CGS>                                       2,669,816         
<TOTAL-COSTS>                              14,778,450 
<OTHER-EXPENSES>                               33,500
<LOSS-PROVISION>                                    0<F2>
<INTEREST-EXPENSE>                                  0
<INCOME-PRETAX>                               984,590
<INCOME-TAX>                                        0
<INCOME-CONTINUING>                           984,590
<DISCONTINUED>                                      0 
<EXTRAORDINARY>                                     0
<CHANGES>                                           0 
<NET-INCOME>                                  984,590
<EPS-PRIMARY>                                     .06
<EPS-DILUTED>                                     .06
<FN>

<F1> The amount of receivables reported is net of $1,317,068 of allowances.

<F2> The total costs include loss provision of $100,000.
</FN>