11 Clinical Trials for Various Conditions
RATIONALE: Congenital toxoplasmosis is an infection caused by the parasitic organism Toxoplasma gondii, and it may be passed from an infected mother to her unborn child. The mother may have mild symptoms or no symptoms; the fetus, however, may experience damage to the eyes, nervous system, skin, and ears. The newborn may have a low birth weight, enlarged liver and spleen, jaundice, anemia, petechiae, and eye damage. Giving the antiparasitic drugs pyrimethamine and sulfadiazine is standard treatment for congenital toxoplasmosis, but it is not yet known which regimen of pyrimethamine is most effective for the disease. PURPOSE: Randomized phase IV trial to determine which regimen of pyrimethamine is most effective when combined with sulfadiazine and leucovorin in treating patients who have congenital toxoplasmosis.
To evaluate the effectiveness of pyrimethamine (given with leucovorin calcium versus placebo (an inactive substance) for the primary prophylaxis (prevention) of cerebral toxoplasmosis in HIV-infected patients. Cerebral toxoplasmosis is one of the most frequently encountered opportunistic infections in the course of AIDS. The mortality (death) rate is estimated to be greater than 50 percent. Pyrimethamine is a drug that appears promising for the primary prevention of cerebral toxoplasmosis in HIV-infected patients.
To compare pyrimethamine and intravenous (IV) clindamycin vs. pyrimethamine and sulfonamides in the treatment of AIDS patients with central nervous system (CNS) Toxoplasma gondii.
To evaluate the safety and tolerance of atovaquone (566C80) in AIDS patients with central nervous system (CNS) toxoplasmosis. To evaluate the efficacy of 566C80 in the acute treatment and suppression of CNS toxoplasmosis in AIDS patients who fail or who cannot tolerate conventional therapy.
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.
To evaluate the effectiveness and toxicity of oral azithromycin and pyrimethamine as acute therapy for toxoplasmic encephalitis in AIDS patients. To assess the toxicity and effectiveness of azithromycin alone as maintenance therapy. Encephalitis caused by Toxoplasma gondii is the most frequent cause of focal central nervous system infection in patients with AIDS. Untreated, the encephalitis is fatal. Standard treatment for toxoplasmic encephalitis is associated with serious adverse effects. Thus, alternative treatments are needed.
To collect information on the effectiveness and toxicity of clindamycin plus pyrimethamine and leucovorin calcium for the treatment of acute toxoplasmic encephalitis in adult patients with AIDS. Toxoplasmic encephalitis (encephalitis caused by Toxoplasma gondii) is the most frequent cause of focal central nervous system infection in patients with AIDS. If untreated, the encephalitis is fatal. At present, it is standard practice to give a combination of pyrimethamine and sulfadiazine to treat toxoplasmic encephalitis. The high frequency of sulfonamide-induced toxicity in AIDS patients often makes completion of a full course of therapy difficult. There is some information that high doses of parenteral (such as by injection) clindamycin used with pyrimethamine may be as effective as pyrimethamine plus sulfadiazine in the management of the acute phase of toxoplasmic encephalitis in patients with AIDS. Administration of parenteral clindamycin for prolonged periods of time, however, is costly, requires hospitalization, and is inconvenient for the patient. There is some indication that treatment of AIDS patients with acute toxoplasmic encephalitis with oral clindamycin may be effective. Leucovorin calcium is useful in preventing pyrimethamine-associated bone marrow toxicity.
To evaluate pyrimethamine as a prophylactic agent against toxoplasmic encephalitis in individuals who are coinfected with HIV and latent Toxoplasma gondii. Toxoplasmic encephalitis is a major cause of illness and death in AIDS patients. Standard treatment for toxoplasmic encephalitis is to combine pyrimethamine and sulfadiazine. Continuous treatment is necessary to prevent recurrence of the disease, but constant use of pyrimethamine/sulfadiazine is associated with toxicity. Clindamycin has been shown to be effective in treatment of toxoplasmic encephalitis in animal studies. This study evaluates pyrimethamine as a preventive treatment against toxoplasmic encephalitis (per 3/26/91 amendment, clindamycin arm was discontinued).
To evaluate the efficacy, safety, and tolerance of atovaquone with either pyrimethamine or sulfadiazine in AIDS patients with toxoplasmic encephalitis. AIDS patients with toxoplasmic encephalitis who receive the standard therapy combination of sulfadiazine and pyrimethamine experience a high frequency of severe toxicity. Atovaquone, an antibiotic that has demonstrated efficacy against toxoplasmosis in animal models and in preclinical testing has been well tolerated, is now available as a suspension, which is more readily absorbed than the tablet form of the drug. The efficacy and safety of atovaquone in combination with sulfadiazine or pyrimethamine will be studied.
Background: - People who are infected with the human immunodeficiency virus (HIV) are at risk of getting certain diseases. Two of these diseases are a type of pneumonia known as PCP and a brain infection called toxoplasmosis. Most people with HIV take antiretroviral (ARV) drugs to treat HIV and lower the risk of infections. However, some ARV drugs may make other drugs used to treat PCP and toxoplasmosis less effective. Researchers want to test specific ARV drugs to see if they affect atovaquone, a drug used to treat PCP and toxoplasmosis. Objectives: - To see if ARV drugs atazanavir-ritonavir or efavirenz lower the blood levels of atovaquone. Eligibility: * Individuals between 18 and 70 years of age who have HIV. * Participants must be taking efavirenz or atazanavir-ritonavir, or not taking any ARV drugs. Design: * Participants will be screened with a physical exam and medical history. They will also have blood and urine tests. * This study has a screening visit and five study visits. Two of the study visits will last about 12 hours; the other three visits will last about 1 hour each. * Participants will receive either a low dose or high dose of atovaquone to take for 14 days. They will record doses and any symptoms on a diary card at home. * After 14 days, participants will have a 12-hour visit to provide blood samples. There will be a wash-out period with no doses for up to 6 weeks. * After the wash-out period, participants will switch dose levels to either the high or low dose. * After 14 days, participants will have a 12-hour visit to provide blood samples.
To evaluate and compare 3 anti-pneumocystis regimens plus zidovudine (AZT) in persons with HIV infection and T4 cell count less than 200 cells/mm3. All persons completing at least 8 weeks of therapy on 081 will be offered the opportunity to participate in the nested study (ACTG 981) of systemic antifungal therapy (fluconazole) versus local therapy (Clotrimazole) for the prevention of serious fungal disease. Persons with HIV disease who are receiving AZT are at risk for PCP, toxoplasmosis, bacterial pneumonia, and other serious infections. It is therefore important to find drugs that can be given along with AZT to control these infections. Aerosolized pentamidine (PEN) has been shown to be useful in preventing PCP and is expected to lower the 2-year risk of PCP. Both sulfamethoxazole/trimethoprim (SMX/TMP) and dapsone probably also provide effective preventive treatment against PCP, and both may be useful in preventing toxoplasmosis and extrapulmonary pneumocystosis.