# Manufacture of aseptic, purified, cryopreserved Plasmodium vivax sporozoites

> **NIH NIH R44** · SANARIA, INC. · 2021 · $977,419

## Abstract

ABSTRACT
Malaria caused by Plasmodium vivax (Pv) parasites is ranked second with respect to the incidence and
severity of disease while Plasmodium falciparum (Pf) malaria is ranked first. However unlike Pf, chemo
prophylactic measures against Pv do not prevent relapses, unique to Pv, that occur due to re-activation of
persistent liver-stage sleeping forms of the parasites called hypnozoites. Primaquine is the only licensed drug
that targets Pv hypnozoites, but it causes life threatening acute hemolytic anemia in patients with G6PD
deficiency, the most prevalent human genetic disorder, affecting 8% of people in malaria-endemic nations.
Efforts to develop better drugs or produce a much needed vaccine are further hampered by the inability to
propagate blood stages of Pv parasites in vitro, unlike Pf. Therefore generating infected mosquitoes for
controlled human malaria infection (CHMI) as a means to assess anti-Pv drugs and vaccines, is entirely reliant
on feeding of mosquitoes on fresh, Pv-infected blood from patients with Pv malaria. Together, these
bottlenecks make the task of developing and testing robust interventions against Pv malaria more challenging
compared to Pf. We have made significant progress under a phase I grant toward establishing and maintaining
a colony of specific pathogen free (SPF) Saimiri boliviensis (Sb). and vialing aseptic, purified Plasmodium
vivax (Pv) sporozoites (SPZ) that were generated in aseptic mosquitoes using infected blood from SPF Sb and
met asepticity and release criteria in all in process and for release. We now outline phase 2 follow-up plans to
manufacture a lot of PvSPZ Challenge in compliance with cGMPs, conduct quality control release and stability
studies, prepare a clinical trial protocol, and prepare and submit an Investigational New Drug (IND) application
to the FDA along with an infectivity study in humanized FRG KO huHEP mice, and an immunogenicity and
protective efficacy study in a mouse model with patent parasitemia as the protection outcome. The product
resulting from studies outlined in this proposal will be called Sanaria® PvSPZ Challenge, and similar to PfSPZ
Challenge will provide the larger malaria community with a tool to assess the efficacy of drugs and vaccines
against Pv malaria with a safer quality-controlled reagent that exhibits minimal variability in potency between
different lots, is logistically more feasible to administer, and is not subject to geographical limitations for
application, compared to traditional CHMI using mosquito bites. It will represent an unprecedented milestone in
the field of vaccinology, and vaccine manufacturing and most importantly it will form the basis of a powerful
vaccine approach to preventing Pv malaria when administered with anti-malarial chemoprophylaxis, the PvSPZ
chemoprophylaxis vaccine (PvSPZ-CVac).

## Key facts

- **NIH application ID:** 10174702
- **Project number:** 5R44AI124867-04
- **Recipient organization:** SANARIA, INC.
- **Principal Investigator:** STEPHEN Lev HOFFMAN
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $977,419
- **Award type:** 5
- **Project period:** 2016-04-21 → 2023-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10174702

## Citation

> US National Institutes of Health, RePORTER application 10174702, Manufacture of aseptic, purified, cryopreserved Plasmodium vivax sporozoites (5R44AI124867-04). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10174702. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*