The long-range goal is to develop new drugs to treat important AIDS-related opportunistic infections and tropical parasitic diseases. STTR Phase I studies confirmed the hypothesis that diamidoxime prodrugs are readily absorbed after oral administration, then metabolized to active diamidines, with excellent antimicrobial activity and reduced host toxicity. Phase I research identified a lead candidate prodrug, DR 289 that is highly active orally in rodent models of P. carinii and African trypanosomiasis, with markedly reduced toxicity compared to pentamidine. The objective in Phase II is to synthesize sufficient quantities of DB289 to perform formal preclinical toxicity and further pharmacological studies required to support IND filing for Phase I clinical trials. The immediate goal is to apply for FDA approval to begin human clinical trials as an orally active agent to treat P. carinii pneumonia. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE