<PAGE>   1


                                                                    EXHIBIT 11.1

                  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
SIX MONTHS ENDED JUNE 30, 1998:
<S>                                         <C>               <C>       <C>                  <C>             <C>           <C>
                                            15,459,166        11           170,050,826
                                            15,460,684        71         1,097,708,564
                                            15,465,729         1            15,465,729
                                            15,467,281        98         1,515,793,538
                                            15,497,443         1            15,497,443
                                                              182        2,814,516,100/182    15,464,374      (10,487,000)   (0.68)


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       (2,055,000)   (0.10)


QUARTER ENDED JUNE 30, 1998:
                                            15,467,281        91         1,407,522,571
                                            15,497,443         1            15,497,443
                                                              92         1,423,020,014/92     15,467,609       (5,576,000)   (0.36)


QUARTER ENDED JUNE 30, 1999:                22,495,050        64         1,439,683,200
         (BASIC)                            22,496,505        26           584,909,130
                                            22,555,435         1            22,555,435
                                                              91         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
</TABLE>