BALTIMORE, July 5 (UPI) -- U.S. scientists report they have found the allergy drug astemizole can also control malarial infection by interfering with a key process of the parasite.
The malaria parasite P. falciparum causes the crystallization of heme molecules from the blood of victims. Some anti-malarials, such as chloroquine, inhibit that reaction, but there are strains of the disease that have become resistant to that drug.
David Sullivan Jr. and colleagues examined the ability of more than 2,600 existing compounds that have entered phase II clinical trials. The screening revealed several compounds with anti-microbial and anti-malarial properties, including the allergy drug astemizole.
Astemizole has been shown to inhibit heme crystallization and could reduce parasitemia in mouse malaria models by a mechanism that seems to be distinct from how chloroquine acts, the researchers said.
The ready availability of astemizole in generic form in countries where malaria is endemic, such as Cambodia and Thailand, make it an attractive choice for anti-malaria strategies. In addition, the researchers said the unique pathway of inhibition by astemizole means it could be used against chloroquine-resistant malaria strains.
The study is reported in the August issue of Nature Chemical Biology.
