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                                 UNITED STATES
 
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549
    
                                   FORM 10-Q/A
     
(MARK ONE)
 
[X]   QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
      EXCHANGE ACT OF 1934
 
                 FOR THE QUARTERLY PERIOD ENDED MARCH 31, 1998
 
                                       OR
 
[ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934
 
           FOR THE TRANSITION PERIOD FROM             TO
 
                          COMMISSION FILE NO. 0-19651
 
                         MAGAININ PHARMACEUTICALS INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)
 
<TABLE>
<S>                                            <C>
                   DELAWARE                                      13-3445668
       (STATE OR OTHER JURISDICTION OF                         (IRS EMPLOYER
        INCORPORATION OR ORGANIZATION)                     IDENTIFICATION NUMBER)
 
              5110 CAMPUS DRIVE                                    19462
        PLYMOUTH MEETING, PENNSYLVANIA                           (ZIP CODE)
   (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)
</TABLE>
 
                                  610-941-4020
              (REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE)
 
     Indicate by check mark whether the Registrant (1) has filed all reports to
be filed by Section 13 of 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.
 
                                Yes [X]  No [ ]
 
     The number of outstanding shares of the Registrant's Common Stock, par
value $.002 per share, on April 22, 1998 was 22,242,890.
 
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                           Explanatory Note:
                           -----------------

     The purpose of this Form 10Q/A is to file Exhibit 27, 

Financial Statement Data Schedule.


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                             EXHIBIT INDEX
                             -------------
    Exhibit No.                                          Description
    -----------                                          -----------

       27                                    Financial Statement Data Schedules
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                                   SIGNATURES
 
     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.
 
                                              MAGAININ PHARMACEUTICALS INC.
 
     ---------------------------------------------------------------------------
                                                       (REGISTRANT)
    
DATE: APRIL 28, 1998
                                            /s/         JAY MOORIN
                                          --------------------------------------
                                                        JAY MOORIN
                                                 CHAIRMAN, PRESIDENT AND
                                                 CHIEF EXECUTIVE OFFICER
 
                                          /s/    MICHAEL R. DOUGHERTY
                                          --------------------------------------
                                                   MICHAEL R. DOUGHERTY
                                               EXECUTIVE VICE PRESIDENT AND
                                                 CHIEF FINANCIAL OFFICER