Sanaria™ PfSPZ Challenge Vaccine

Malaria Clinical Trial

Official title: A Phase I, Randomized Malaria Challenge Study of Intradermally-Administered Infectious (Replication-intact), Cryopreserved Plasmodium Falciparum Sporozoites (PfSPZ Challenge) in Malaria-Naïve Adults

Status Completed

Clinical Trial Summary

This study will randomize 30 healthy adult participants to one of three cohorts comprised of six groups of 5 individuals per group to simultaneously receive PfSPZ Challenge via the ID route. The goal will be to determine the optimal dose required to achieve 100% infectivity (ID100) of adult volunteers with P. falciparum malaria.

Clinical Trial Description

Study Phase and Design Phase I with experimental malaria challenge. The study will enroll 30 healthy adult participants randomized to one of three cohorts comprised of six groups of 5 individuals per group to simultaneously receive PfSPZ Challenge via the ID route. The goal will be to determine the optimal dose required to achieve 100% infectivity (ID100) of adult volunteers. The parameters of 1) dose (number of sporozoites) 2) number of injections and 3) aliquot volume will be studied; adding to previous data collected at the University of Nijmegen. The following single time point inoculation regimens (a-f) will be assessed: Cohort 1: Medium dose, medium aliquot volume: a. 10,000 PfSPZ ID in 2 divided doses of 50 microliter aliquot volume b. 10,000 PfSPZ ID in 8 divided doses of 50 microliter aliquot volume Cohort 2: Medium dose, low aliquot volume: c. 10,000 PfSPZ ID in 2 divided doses of 10 microliter aliquot volume d. 10,000 PfSPZ ID in 8 divided doses of 10 ml aliquot volume Cohort 3: High dose, low aliquot volume: e. 50,000 PfSPZ ID in 2 divided doses of 10 ml aliquot volume f. 50,000 PfSPZ ID in 8 divided doses of 10 ml aliquot volume. Safety, tolerability and efficacy of the inoculation regimens will be evaluated. All 30 volunteers will be evaluated as part of an inpatient stay (Days 8-18 post-injection) to diagnose and treat Pf malaria infection with chloroquine. Following review, and with the assistance of an independent SMC, 2 regimens will be chosen for further testing in DMID 11-0042. The following criteria strategy will be employed in the order listed: 1. Regimen necessary to achieve ID100 of adult volunteers; 2. Regimen eliciting Pf patency and parasite density (as detected by qRT-PCR) that most closely approximates patency rates experienced after mosquito challenge; 3. Regimen requiring the least number of injections; 4. Regimen utilizing the fewest number of PfSPZ; 5. Volume of administration considered to be the easiest to administer by the clinicians. Chloroquine sub-study: Eighteen of thirty participants (3 volunteers from each of the six groups comprised of 5-subjects/group) will be assigned to participate in a CQ and possibly desethylchloroquine blood and urine study designed to assess the drug kinetics of CQ over the course of four weeks after standard CQ dose administration. ;

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator)

Related Conditions & MeSH terms

• Malaria

• NCT number: NCT01546389
• Study type: Interventional
• Source: National Institute of Allergy and Infectious Diseases (NIAID)
• Status: Completed
• Phase: Phase 1
• Start date: April 2012
• Completion date: April 2013