Phase 1 Safety Evaluation of PfSPZ Vaccine in Pregnant Women in Mali (MalVIP1)

• Status: Not yet recruiting
• Trial end date: 2024-11-30

Summary

Study Description:

A randomized double blind, placebo-controlled study to assess the safety, tolerability, immunogenicity and protective efficacy of a 1, 8, 29-day regimen of 9x105 PfSPZ of PfSPZ Vaccine or placebo (normal saline) in healthy pregnant women and their fetus/newborn. The first immunization is to be administered at 16 0/7 to 32 6/7 weeks of gestation and targeted to be completed prior to delivery. Offspring and post-partum women will be followed for 12 months post-delivery.

The study is composed of two cohorts (3rd trimester: Arms 1A, 2A, 2nd trimester: Arms 1B, 2B) with two arms (PfSPZ Vaccine, normal saline placebo) and associated offspring. Enrollment and vaccinations will be staggered for safety with only third trimester women (n=30; based on guidance provided by regulatory bodies) enrolling first in two separate subsets (n=10 [5 PfSPZ Vaccine/5 normal saline], n=20 [10 PfSPZ Vaccine/10 normal saline]) and receiving all three doses of vaccine in a staggered manner and undergoing safety reviews prior to further enrollments. Third trimester enrollment in this staggered manner is to account for any significant events occurring immediately post initial vaccinations with the smaller first subset of women (n=10; DSMB review). After all third trimester pregnancy outcomes are reviewed (by DSMB, FDA, Sponsor, EC/IRB), an additional cohort of women in their second trimester will be vaccinated in two separate subsets (n=10 [5 PfSPZ Vaccine/5 normal saline], n=20 [10 PfSPZ Vaccine/10 normal saline]) separated by at least six weeks. A longer time period of review will be conducted during the 2nd trimester out of additional safety measures to ensure no significant events of concern occur post receipt of a full vaccination series (n=10; DSMB review) before proceeding to the last subset of women (n=20).

Arm 1 (9x105 PfSPZ Vaccine): (n = 30) pregnant women will receive three doses of PfSPZ Vaccine (9x10^5 PfSPZ) via direct venous inoculation (DVI) at 1, 8, 29 days

• Arm 1A: (n=15) women 28 0/7 to 32 6/7 WGA (third trimester) at time of first vaccination

• Arm 1B: (n=15) women 16 0/7 to 27 6/7 WGA (second trimester) at time of first vaccination

Arm 2 (normal saline): (n = 30) pregnant women will receive normal saline via DVI at 1, 8, 29 days

• Arm 2A: (n=15) women 28 0/7 to 32 6/7 WGA (third trimester) at time of first vaccination

• Arm 2B: (n=15) women 16 0/7 to 27 6/7 WGA (second trimester) at time of first vaccination

All participants will receive intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) as per standard of care in Mali. The study team will coordinate with the women s antenatal care (ANC) provider to time her IPTp prior to vaccine dose 1 (approximately 2 weeks prior) and between vaccine dose 2 and dose 3 (approximately 2 weeks prior to dose 3) within the protocol defined windows.

Pregnant women will be monitored closely for the duration of their pregnancy and for at least 12 months post-partum for safety, tolerability, immunogenicity, and malaria infection during the follow-up period.

Infants (n=up to 60) born to enrolled women will also be monitored closely for 12 months post-delivery for safety, immunogenicity, and malaria infection.

Objectives:

Primary Objectives:

-To describe the safety of PfSPZ Vaccine at 9x105 PfSPZ at dosing schedule of 1, 8, 29 days in pregnant women and their fetuses using a composite measure of adverse maternal and birth outcomes

Secondary Objectives:

• To describe the safety and tolerability of PfSPZ Vaccine at 9x10^5 PfSPZ at dosing schedule of 1, 8, 29 days in pregnant women and their fetuses using solicited adverse events (AEs), unsolicited AEs, and laboratory abnormalities

• To describe the safety of maternal vaccination with PfSPZ Vaccine in infants

Exploratory Objectives:

• To explore the protective efficacy against Pf malaria of PfSPZ Vaccine in pregnant women (peripheral blood, placenta) and infants (peripheral, cord blood)

• To assess the immune response to PfSPZ Vaccine in pregnant women and infants and their association with protection against Pf malaria

• To assess genetic relatedness of the PfSPZ Vaccine parasite strain to malaria infection parasites in pregnant women and infants

Endpoints:

Primary Endpoints:

-Composite endpoint of adverse maternal or birth outcomes defined as: preterm birth, miscarriage, stillbirth, early neonatal death, direct maternal death, low birth weight, small for gestational age (counts and proportions)

Secondary Endpoints:

-Safety and tolerability in pregnant women and their fetuses

• Solicited local and systemic AEs through 7 days post injection (counts and proportions)

• Clinical laboratory parameters through 14 days post injection (counts and proportions)

• All uns...

• Phase: Phase 1

Details

• Lead Sponsor: National Institute of Allergy and Infectious Diseases (NIAID)