Safety and immunogenicity of ChAd63-KH vaccine in post-kala-azar dermal leishmaniasis patients in Sudan
Brima M. Younis, Mohamed Osman, Eltahir Awad Gasim Khalil, Francesco Santoro, Simone Furini, Rebecca Wiggins, Ada Keding, Monica Carraro, Anas E.A. Musa, Mujahid A.A. Abdarahaman, Laura Mandefield, Martin Bland, Toni Aebischer, Rhian Gabe, Alison Layton, Charles Lacey, Paul M. Kaye, Ahmed Musa
Abstract
v.p. (adults and adolescents), with primary (safety) and secondary (clinical response and immunogenicity) endpoints evaluated over 42-120 days follow-up. AmBisome was provided to patients with significant remaining disease at their last visit. ChAd63-KH vaccine showed minimal adverse reactions in PKDL patients and induced potent innate and cell-mediated immune responses measured by whole-blood transcriptomics and ELISpot. 7/23 patients (30.4%) monitored to study completion showed >90% clinical improvement, and 5/23 (21.7%) showed partial improvement. A logistic regression model applied to blood transcriptomic data identified immune modules predictive of patients with >90% clinical improvement. A randomized controlled trial to determine whether these clinical responses were vaccine-related and whether ChAd63-KH vaccine has clinical utility is underway.