Efficacy, safety, and tolerability of albendazole and ivermectin based regimens for the treatment of microfilaraemic loiasis in adult patients in Gabon: A randomized controlled assessor blinded clinical trial

PLoS Negl Trop Dis. 2023 Aug 28;17(8):e0011584. doi: 10.1371/journal.pntd.0011584. eCollection 2023 Aug.

Abstract

Background: There is a lack of systematic evidence for strategies to control loiasis transmission in highly endemic regions. Here we assessed albendazole and ivermectin based treatment regimens to reduce Loa loa microfilaraemia in Gabon.

Methods: Eligible adult patients with L. loa microfilaraemia between 5,000 and 50,000 microfilariae/ml were randomized to either a control or one of three intervention groups (1:2:2:2 allocation ratio) consisting of three-week twice daily 400mg oral albendazole followed by 1) no treatment, 2) two further weeks of twice daily 400mg albendazole, or 3) a single dose of ivermectin in this open label randomized assessor blinded controlled clinical trial. The primary outcome was the proportion of participants with L. loa microfilaraemia ≤ 100 mf/ml at Day 168.

Results: In the efficacy-population of 42 patients 0 (0%; control group), 1 (9%; 3-week albendazole), 5 (39%; 5-weeks albendazole) and 2 (22%; 3-week albendazole plus single dose ivermectin) participants met the primary outcome of microfilaraemia below 100/ml at day 168. A 80-90% reduction of microfilaraemia was observed in the active treatment groups.

Conclusion: The 5-week regimen of albendazole or a 3-week regimen of albendazole followed by ivermectin were most efficacious to reduce microfilaraemia. All therapeutic regimens were well tolerated and safe.

Trial registration: Trial registered at the Pan-African Clinical Trials Registry: PACTR201807197019027.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Albendazole* / adverse effects
  • Animals
  • Clinical Protocols
  • Fishes
  • Gabon
  • Humans
  • Ivermectin / adverse effects
  • Loiasis* / drug therapy

Substances

  • Albendazole
  • Ivermectin

Associated data

  • PACTR/PACTR201807197019027

Grants and funding

This study was funded by the Federal Ministry of Science, Research and Economy of the Republic of Austria (https://www.bmbwf.gv.at/) (MR). This activity was part of the European and Developing Countries Clinical Trials Partnership 2 programme, which is supported by the European Union. The study was also financially supported by the Centre de Recherches Medicales de Lambaréné, Gabon (RZM), and the Bernhard Nocht Institute for Tropical Medicine, Germany (MR). The funders and institutions had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.