IAVI
Non-profit vaccine developer; rVSV platform received $3.2m CEPI grant for Bundibugyo master seed stock.
Last refreshed: 9 June 2026 · Appears in 1 active topic
Can IAVI's rVSV platform produce usable Bundibugyo seed stock fast enough to matter in an active outbreak?
Timeline for IAVI
Received $3.2m CEPI commitment for rVSV master seed stock
Pandemics and Biosecurity: $112m for vaccines, none for the wards- What is IAVI and what vaccines has it developed?
- IAVI (International AIDS Vaccine Initiative) is a New York-based non-profit that develops vaccines for HIV and emerging infectious diseases. Its rVSV platform contributed to Ervebo, the only approved Zaire ebolavirus vaccine; it is now developing an rVSV Bundibugyo candidate.
- What is rVSV and why is it used in Ebola vaccines?
- rVSV (recombinant vesicular stomatitis virus) is a viral vector technology that can be engineered to display proteins from other pathogens. It was used in Ervebo, the only approved Zaire ebolavirus vaccine, because rVSV-based vaccines can be manufactured rapidly and often generate strong immune responses.
- Why is there no Bundibugyo Ebola vaccine yet?
- Bundibugyo ebolavirus is a distinct species from Zaire ebolavirus. Vaccines like Ervebo target Zaire-specific proteins and do not cover Bundibugyo. A new validated candidate is required, and the absence of prior commercial interest meant no manufacturer had advanced one to clinical stage before the 2026 outbreak.Source: WHO / CEPI
- What is vaccine master seed stock and why does it matter?
- Master seed stock is the GMP-certified biological starting material from which all clinical-grade vaccine doses are derived. Without it, a vaccine candidate cannot enter formal trials. CEPI's $3.2m to IAVI funds production of this foundational material for the rVSV Bundibugyo candidate.Source: CEPI
Background
IAVI (International AIDS Vaccine Initiative) is a New York-based non-profit scientific organisation founded in 1996 that develops vaccines for HIV and emerging infectious diseases in low- and middle-income countries. IAVI operates its own clinical development programmes and collaborates with academic, government, and commercial partners to advance vaccine platforms. Its primary scientific platform is based on replication-competent recombinant vesicular stomatitis virus (rVSV), the same vector technology used in rVSV-ZEBOV (Merck's Ervebo), the only approved vaccine against Zaire ebolavirus. IAVI's rVSV work has expanded from HIV to Filovirus pathogens, positioning the organisation as a niche developer of vector-based vaccines for pathogens with limited commercial markets.
On 1 June 2026 IAVI received $3.2 million from CEPI to manufacture master seed stock of its rVSV-based Bundibugyo ebolavirus vaccine candidate. Master seed stock is the regulatory-compliant biological starting material from which clinical doses are derived; producing it under GMP conditions is the first manufacturing step before Phase 1 trials can begin. The investment is the smallest of CEPI's three Bundibugyo platform bets but addresses a critical bottleneck: without characterised seed stock, no rVSV candidate can enter formal clinical development. IAVI's rVSV technology is validated at scale through Ervebo's use during the 2018-2020 DRC Zaire outbreak, but Bundibugyo ebolavirus is a distinct species requiring its own validated candidate. There are no approved vaccines or treatments for Bundibugyo ebolavirus as of June 2026.
