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                  ARONEX PHARMACEUTICALS, INC. AND SUBSIDIARIES

         STATEMENT REGARDING COMPUTATION OF PER SHARE EARNINGS

The following reflects the information used in calculating the number of
shares in the computation of net loss per share for each of the periods set
forth in the Statements of Operations.

<TABLE>
<CAPTION>
                                                                                                                     INCOME
                                                                                        AVERAGE                      (LOSS)
                                                     DAYS                               SHARES           INCOME        PER
                                    SHARES        OUTSTANDING     SHARES X  DAYS      OUTSTANDING        (LOSS)       SHARE
<S>                                 <C>             <C>             <C>            <C>                  <C>           <C>
SIX MONTHS ENDED JUNE 30, 1999:
                                    16,379,309         3              49,137,927
                                    16,415,664        50             820,783,200
                                    22,415,664        14             313,819,296
                                    22,463,211        21             471,727,431
                                    22,474,987         1              22,474,987
                                    22,494,671         1              22,494,671
                                    22,495,050        64           1.439,683,200
                                    22,496,505        26             584,909,130
                                    22,555,435         1              22,555,435
                                                     181           3,747,585,277 /181  20,704,891       (1,906,000)    (0.09)

SIX MONTHS ENDED JUNE 30, 2000:
                                    22,853,782        21             479,929,422
                                    22,873,782         3              68,621,346
                                    22,876,765         4              91,507,060
                                    22,877,930        12             274,535,160
                                    22,879,230        23             526,222,290
                                    22,888,646         6             137,331,876
                                    22,905,144        14             320,672,016
                                    22,922,078        54           1,237,792,212
                                    25,854,652        44           1,137,604,688
                                    25,890,127         1              25,890,127
                                                     182           4,300,106,197 /182  23,626,957       (7,918,000)    (0.34)

QUARTER ENDED JUNE 30, 1999:
               (BASIC)              22,495,050        64           1,439,683,200
                                    22,496,505        26             584,909,130
                                    22,555,435         1              22,555,435
                                                      92           2,047,147,765  /91  22,496,129        1,269,000      0.06

QUARTER ENDED JUNE 30, 1999:        22,652,230        19             430,392,370
              (DILUTED)             22,652,380        14             317,133,320
                                    22,652,592         8             181,220,736
                                    22,661,974        10             226,619,740
                                    23,236,687        14             325,313,618
                                    23,237,687        25             580,942,175
                                    23,297,072         1              23,297,072
                                                      91           2,084,919,031  /91  22,911,198        1,269,000      0.06

QUARTER ENDED JUNE 30, 2000:
                                    22,922,078        47           1,077,337,666
                                    25,854,652        44           1,137,604,688
                                    25,890,127         1              25,890,127
                                                      92           2,240,832,481  /92  24,356,875       (4,466,000)    (0.18)

</TABLE>