Comparison of Two Dosage Regimens of Oral Dapsone for Prophylaxis of Pneumocystis Carinii Pneumonia in Pediatric HIV Infection

Comparison of Two Dosage Regimens of Oral Dapsone for Prophylaxis of Pneumocystis Carinii Pneumonia in Pediatric HIV Infection

Primary: To compare the toxicity of daily versus weekly dapsone in HIV-infected infants and children; to study the pharmacokinetics of orally administered dapsone in HIV-infected infants and children.

Secondary: To obtain information on the rate of Pneumocystis carinii pneumonia ( PCP ) breakthrough in children receiving two different dose regimens of dapsone.

Prophylaxis for Pneumocystis carinii pneumonia ( PCP ) is recommended for all HIV-infected children considered to be at high risk. Approximately 15 percent of children are intolerant to trimethoprim / sulfamethoxazole, the first choice drug for PCP prophylaxis. Since many children are also unable to take or tolerate aerosolized pentamidine, dapsone is a second choice for PCP prophylaxis. The most favorable dose regimen for dapsone has not been established.

Prophylaxis for Pneumocystis carinii pneumonia ( PCP ) is recommended for all HIV-infected children considered to be at high risk. Approximately 15 percent of children are intolerant to trimethoprim / sulfamethoxazole, the first choice drug for PCP prophylaxis. Since many children are also unable to take or tolerate aerosolized pentamidine, dapsone is a second choice for PCP prophylaxis. The most favorable dose regimen for dapsone has not been established.

Ninety-six HIV-infected infants and children who are intolerant to trimethoprim / sulfamethoxazole ( TMP / SMX ) are randomized to receive oral dapsone in a lower dose once daily or at a higher dose once weekly. Treatment continues until the last patient enrolled has received at least 3 months of therapy. Blood samples are drawn between weeks 4 and 8, at weeks 12 and 24, and every 3 months thereafter during dapsone administration.

Inclusion Criteria

Concurrent Medication:

Allowed:

• Rifampin and rifampin derivatives for up to 1 week during the study.
• Rifabutin or other drugs that could alter dapsone metabolism (if prescribed by the child's primary care physician).

Patients must have:

• Evidence of HIV infection.

PER AMENDMENT 11/16/95:

• Children who require prophylaxis. (Was written - Risk of developing PCP.)
• Known intolerance to TMP / SMX.
• Consent of parent or guardian. Patients entering this study may be co-enrolled in other ACTG pediatric studies.

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms and conditions are excluded:

• Glucose-6-phosphate dehydrogenase deficiency.
• Known allergy to dapsone.

Concurrent Medication:

Excluded:

• Rifampin, rifampin derivatives, or oxidant drugs for more than 1 week.

Patients with the following prior conditions are excluded:

• Serious or life-threatening reactions to TMP / SMX (e.g., anaphylaxis, Stevens-Johnson syndrome, hypotension) that would contraindicate therapy with sulfa drugs.

Prior Medication:

Excluded:

• Prior dapsone.
• Rifampin, rifampin derivatives, or oxidant drugs within 1 week prior to study entry.
• TMP / SMX within 7 days prior to study entry (and toxicity must be clearly resolving).

Prior Treatment:

Excluded:

• RBC transfusion within 4 weeks prior to study entry.