Randomized, placebo-controlled study in 16 cognitively unimpaired participants met safety and immunogenicity objectives; all 12 vaccine recipients developed anti-Aβ antibodies after two priming doses

• Randomized, double-blind, placebo-controlled Phase 1 trial enrolled 16 cognitively unimpaired participants: 12 received AV-1959R and four received placebo.
• All 12 AV-1959R recipients developed anti-Aβ antibody responses after two doses administered one month apart.
• The study assessed initial safety and immunogenicity and was not designed to evaluate clinical efficacy.
• The immunogenicity results position AV-1959R as the most advanced amyloid vaccine assessed in clinical trials to date

IRVINE, Calif., Oct. 13, 2026 /PRNewswire/ — Nuravax, Inc. and the Institute for Molecular Medicine (IMM) today announced publication in Molecular Neurodegeneration of results from a randomized, double-blind, placebo-controlled Phase 1 clinical trial of AV-1959R, an investigational amyloid-beta (Aβ) vaccine based on the MultiTEP platform.

The study enrolled 16 participants: 12 received AV-1959R and 4 received placebo. According to the publication, the study met its safety and immunogenicity objectives. It was not designed or powered to assess clinical efficacy or establish the safety profile required for broader use.

Phase 1 immunogenicity results

After two priming immunizations one month apart, all 12 AV-1959R recipients developed anti-Aβ antibody responses. Geometric mean titers (GMTs) were 60,240 and 69,530 in the 100 µg and 300 µg cohorts, respectively. None of the four placebo recipients showed a measurable response; their anti-Aβ42 antibody levels remained at baseline, with a reported GMT of 156.

Exploratory analyses showed stronger antibody binding to aggregated Aβ species, including protofibrils and fibrils, weaker binding to oligomers, and little to no binding to monomeric Aβ. Serum from vaccinated participants also bound amyloid plaques in cortical tissue from Alzheimer’s disease cases but not in non-Alzheimer’s control tissue.

Antibody-kinetics modeling projected titers could remain approximately fivefold above baseline for about one year after priming, supporting evaluation of an annual booster strategy in future studies. Durability and clinical relevance remain to be established prospectively.

“Amyloid-beta is a self-protein, which makes it difficult to generate a strong, targeted immune response against pathological forms of the protein,” said Dr. Michael Agadjanyan, head of Molecular Immunology at IMM and founder of Nuravax. “The Phase 1 results provide clinical evidence that MultiTEP-based AV-1959R can overcome immune tolerance and induce antibodies that preferentially recognize aggregated Aβ. We believe these findings support continued development of clinical trials.”

Phase 2 trial with AV-1959R

Nuravax/IMM plans a Phase 2 trial for the AV-1959R preventive vaccine. This unique preventive study aims to enroll cognitively unimpaired individuals with biomarker-confirmed amyloid pathology across low and high amyloid burden, expand safety monitoring to include ARIA-H and ARIA-E, and evaluate surrogate efficacy using amyloid- and tau-related brain and blood biomarkers.

“This 16-participant Phase 1 study provides an initial assessment of safety and immunogenicity but cannot establish the safety or efficacy of the vaccine,” said Lon S. Schneider, professor of psychiatry, neurology and gerontology at the Keck School of Medicine of USC and a co-author of the publication. “The planned Phase 2 study is designed to evaluate these questions in participants with biomarker-confirmed amyloid pathology.”

About AV-1959R

AV-1959R is an investigational amyloid-beta vaccine based on the MultiTEP platform and designed to elicit antibody responses against pathological forms of Aβ. AV-1959R was developed to be used in individuals with evidence of amyloid pathology who are at risk of Alzheimer’s. It is not approved for any use, and its safety and efficacy have not been established.

About publication and trial information

Hovakimyan A., Madoyan H., Najarzadeh Z. et al. “A randomized, placebo-controlled, double blind Phase 1 trial of the Aβ vaccine, AV-1959R, in non-cognitively impaired participants: prelude for secondary preventive therapy in preclinical AD.” Article in Press: “Molecular Neurodegeneration (July 2026): https://link.springer.com/article/10.1186/s13024-026-00980-y  

About Nuravax, Inc.

Nuravax, Inc. is a clinical-stage biotechnology company in Irvine, Calif., developing vaccines for neurodegenerative diseases. A spin-off of the non-profit Institute for Molecular Medicine, Nuravax licenses the MultiTEP vaccine platform, which combines self-antigen B-cell epitopes with foreign T-helper epitopes to elicit antibody responses against proteins the immune system would otherwise tolerate. The company’s programs apply MultiTEP to amyloid-beta, tau, and alpha-synuclein.

About the Institute for Molecular Medicine

The Institute for Molecular Medicine is a non-profit biomedical research organization in Huntington Beach, Calif. IMM developed the MultiTEP platform over two decades and supplied the AV-1959R drug product developed under the NIH cooperative program U01 AG060965.

Phase 1 trial registrations: ANZCTR ACTRN12624000737538 and NCT06831812.

Forward-Looking Statements

This press release contains forward-looking statements regarding AV-1959R, including planned clinical development, future trial design, biomarker assessments, and potential booster strategies. Such statements are based on current expectations and are subject to risks and uncertainties that could cause actual results to differ materially. Clinical development is inherently uncertain, and results from an early-stage study may not predict later-stage results. Forward-looking statements speak only as of the date of this release, and Nuravax undertakes no obligation to update them except as required by law.

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SOURCE Nuravax, Inc.