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                                                                    EXHIBIT 11.1

                               ILEX ONCOLOGY, INC.


                        COMPUTATION OF NET LOSS PER SHARE

                    (In Thousands, Except Per Share Amounts)


<TABLE>
<CAPTION>

                                                                                     Years Ended December 31
                                                                              ------------------------------------
                                                                                1996          1997          1998
                                                                              --------      --------      --------
<S>                                                                           <C>           <C>           <C>      
COMPUTATION OF BASIC NET LOSS PER SHARE:
   Net loss                                                                   $   (615)     $ (8,682)     $(21,228)
                                                                              --------      --------      --------

   Weighted average number of shares of common stock and common stock
     equivalents outstanding-
       Weighted average shares of common stock outstanding                       1,188        12,118        12,450
       Common stock equivalents applicable to convertible preferred
         stock (b)                                                               7,062          --            --   
       Weighted average number of common stock equivalents applicable to
         stock options and warrants (b)                                            494          --            --
                                                                              --------      --------      --------

                                                                                 8,744        12,118        12,450
                                                                              ========      ========      ========

   Basic net loss per share                                                   $   (.07)     $   (.72)     $   1.71
                                                                              ========      ========      ========

COMPUTATION OF DILUTED NET LOSS PER SHARE:
   Net loss                                                                   $   (615)     $ (8,682)     $(21,228)
                                                                              ========      ========      ========

   Weighted average shares of common stock outstanding                           1,188        12,118        12,450
   Common stock equivalents applicable to convertible preferred stock (b)
                                                                                 7,062          --            --   
   Weighted average number of common stock equivalents applicable to
     stock options and warrants (b)                                                559         1,204           411
                                                                              --------      --------      --------

                                                                                 8,809        13,322        12,861
                                                                              ========      ========      ========

   Diluted net loss per common share and common share equivalents (a)
                                                                              $   (.07)     $   (.65)     $  (1.65)
                                                                              ========      ========      ========
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           (a)    This calculation is submitted in accordance with Item
                  601(b)(11) of Regulation S-K although it is not required by
                  SFAS No. 128 because it is antidilutive.

           (b)    For December 31, 1995 and 1996, convertible stock, stock
                  options and stock warrants issued within one year prior to an
                  initial public offering with a conversion price or exercise
                  price below the estimated initial public offering price have
                  been included as outstanding for all periods specified by SAB
                  No. 83.