NCT07060508

L9LS in Women of Childbearing Potential in Mali

Safety and Efficacy of L9LS, a Human Monoclonal Antibody Against Plasmodium Falciparum, in a Randomized, Double-Blind, Placebo-Controlled Trial of Women of Childbearing Potential (WOCBP) in Mali

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 290 (estimated)
• Sponsor: National Institute of Allergy and Infectious Diseases (NIAID) · NIH
• Sex: All
• Age: 18 Years – 49 Years
• Healthy volunteers: Accepted

Summary

Safety and Efficacy of L9LS, a Human Monoclonal Antibody Against Plasmodium falciparum, in a Randomized, Double-Blind, Placebo-Controlled Trial of Women of Childbearing Potential (WOCBP) in Mali

Detailed description

This is a phase 2 trial evaluating the safety and tolerability of a 1-time subcutaneous (SC) administration of L9LS, as well as its protective efficacy against naturally occurring Plasmodium falciparum (Pf) infection over a 6-month malaria season. The primary study hypothesis is that L9LS will be safe and protective against malaria infection. As a secondary objective, the efficacy of L9LS among female participants of childbearing potential within three body weight strata will be compared to placebo. Before study agent administration, all participants will be given artemether-lumefantrine (AL) to clear any preexisting Pf blood stage infection. This is a randomized, double-blind, placebo-controlled study mainly in WOCBP, weight-stratified (N=270 total), with 2 treatment arms: L9LS 1800 mg SC (n=180) and placebo (n=90) to assess safety and protective efficacy of L9LS. A separate open label male only arm (n=20) will assess sex-differences in the pharmacokinetics (PK) of L9LS at a dose of 1800 mg SC. Male participants will be enrolled during the same time period as the WOCBP arm. Participants will receive the study agent and be followed at visits on study Days 1, 3, 7, 14, 21, and 28 days later, and once every 2 weeks thereafter through 24 weeks. Primary study assessments include physical examination, blood collection for identification of Pf infection and other research laboratory evaluations.

Conditions

• Malaria

Interventions

Type	Name	Description
BIOLOGICAL	Single dose of 1800 mg L9LS SC	A human monoclonal antibody to protect against Plasmodium falciparum.
OTHER	Placebo	Normal saline

Timeline

• Start date: 2025-07-22
• Primary completion: 2026-04-01
• Completion: 2026-04-01
• First posted: 2025-07-11
• Last updated: 2026-02-17

Locations

3 sites across 1 country: Mali

Regulatory

• FDA-regulated drug study