New Drug Combination Shows Promise in Treating Intestinal Worm Infections: Lancet

New Delhi: A fixed-dose combination (FDC) of albendazole and ivermectin offers a promising solution for combating soil-transmitted helminths (STH), according to a phase II-III clinical trial published in The Lancet Infectious Diseases. The study highlights the potential of this drug regimen in achieving control targets for STH set by the World Health Organization’s (WHO) 2021–2030 Roadmap for Neglected Tropical Diseases.

STH infections, caused by parasitic worms such as Ascaris lumbricoides, Trichuris trichiura, and hookworms (Ancylostoma duodenale and Necator americanus), are transmitted through contaminated soil or water. These infections disproportionately affect children and women of reproductive age, leading to malnutrition, anemia, and other health issues. The new combination treatment addresses gaps in current therapies, particularly for T. trichiura, which has shown resistance to existing drugs like albendazole.

The trial, conducted by an international team led by the Barcelona Institute of Global Health (ISGlobal), evaluated the safety, efficacy, and palatability of a combination tablet targeting T. trichiura, hookworm, and Strongyloides stercoralis. The study involved 1,001 school-aged children from Ethiopia, Kenya, and Mozambique between January 2022 and March 2023. Participants were divided into three groups: 243 received albendazole alone, 381 received a single dose of the combination therapy (FDC×1), and 377 received three consecutive daily doses (FDC×3).

The results demonstrated significantly higher cure rates for T. trichiura in both FDC groups compared to albendazole alone. FDC×3 achieved a cure rate of 97.2%, while FDC×1 had an 82.9% success rate, compared to just 35.9% for albendazole. For hookworm infections, FDC×3 achieved a 95% cure rate, surpassing albendazole’s 65.1%. The single-dose combination (FDC×1) was also effective, with a cure rate of 79.8%.

The combination therapy also showed promise against S. stercoralis, although the sample size for this parasite’s evaluation was insufficient for conclusive results. Adverse events in the FDC groups were mild to moderate gastrointestinal symptoms, resolving within 48 hours without intervention.

The study highlights the limitations of current deworming strategies, which primarily rely on albendazole. While effective against A. lumbricoides, albendazole has shown declining efficacy against T. trichiura, likely due to emerging drug resistance. Moreover, it is not effective against S. stercoralis. The combination of albendazole and ivermectin offers a broader spectrum of activity and could potentially improve global efforts to control STH infections.

“These findings open opportunities for controlling all soil-transmitted helminth species, including potentially Strongyloides stercoralis,” the researchers told IANS, emphasizing the need for larger-scale studies to further evaluate the safety and efficacy of this regimen.

If widely adopted, the combination therapy could significantly enhance treatment outcomes in endemic regions, improving the health and well-being of at-risk populations while advancing progress toward global STH control goals.