ONCE-WEEKLY ADMINISTRATION OF DAPSONE PYRIMETHAMINE VS AEROSOLIZED PENTAMIDINE AS COMBINED PROPHYLAXIS FOR PNEUMOCYSTIS-CARINII PNEUMONIA AND TOXOPLASMIC ENCEPHALITIS IN HUMAN IMMUNODEFICIENCY VIRUS-INFECTED PATIENTS

To evaluate combined prophylaxis for Pneumocystis carinii pneumonia (P CP) and toxoplasmic encephalitis, 533 patients with symptomatic human immunodeficiency virus infection and/or CD4 lymphocyte counts of <200/ mu L were randomized to receive dapsone/pyrimethamine (200/75 mg once weekly) or aerosolized pentamidine (300 mg every 4 weeks). The median CD4 lymphocyte count was 110/mu L; 47.5% were seropositive for toxopla sma antibodies. The median duration of follow-up was 483 days. In the intent-to-treat analysis, 12 cases of PCP and 14 of toxoplasmic enceph alitis occurred in the dapsone/pyrimethamine group and 13 and 20 cases , respectively, in the aerosolized pentamidine group (adjusted relativ e risk for toxoplasmosis, 0.56; P = .10). However, only two of the 14 cases of toxoplasmic encephalitis in the dapsone/pyrimethamine group d eveloped during actual treatment. The mortality among the two groups w as similar. Dapsone/pyrimethamine was not tolerated by 30% of particip ants. A subanalysis of 240 matched, tolerant patients yielded a relati ve risk for toxoplasmosis of 0.21 (P = .014), a result favoring the us e of dapsone/pyrimethamine. Dapsone/pyrimethamine was as effective as aerosolized pentamidine as prophylaxis for PCP and significantly reduc ed the incidence of toxoplasmic encephalitis among those participants who tolerated it.