Clinical Trial: A Study of Pyrimethamine in the Treatment of Infection by a Certain Parasite in HIV-Positive Patients

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional




Official Title: Pyrimethamine Pharmacokinetics in HIV Positive Patients Seropositive for Toxoplasma Gondii

Brief Summary:

To determine the manner in which pyrimethamine is metabolized and excreted in patients currently receiving zidovudine (AZT). An important goal of this measurement is to establish the optimal dose of pyrimethamine necessary to prevent the development of toxoplasmosis in AIDS patients or delay the subsequent return of toxoplasmic encephalitis.

Encephalitis caused by Toxoplasma gondii has emerged as the most frequent cause of focal central nervous system infection in patients with AIDS. Untreated, the encephalitis is fatal. The best treatment for this disease has not been determined. Presently it is standard practice to administer a combination of pyrimethamine and sulfadiazine. Little is known about the pharmacokinetics of pyrimethamine in patients with AIDS receiving AZT. Furthermore, there are reports that patients already exposed to toxoplasmosis may not have uniform absorption of pyrimethamine.