BOSTON, U.S. & CAMBRIDGE, U.K. — August 25, 2026
Apollo Therapeutics announced positive immunogenicity and cross-species activity data from Part A of the Phase 1 clinical trial evaluating APL-10456, an investigational pan-rhinovirus vaccine designed to prevent COPD exacerbations and asthma exacerbations. The company also confirmed completion of enrollment and dosing in the randomized controlled Phase 1 study involving 144 participants. The initial findings support continued development of APL-10456 as a potential preventive approach against rhinovirus-driven respiratory exacerbations, an area where no approved vaccine is currently available.
APL-10456 Targets Broad Rhinovirus Diversity
The central scientific challenge addressed by APL-10456 is the extensive genetic and antigenic diversity of rhinoviruses. Approximately 180 genetically distinct strains are distributed across three major species: RV-A, RV-B and RV-C. This diversity has historically complicated efforts to develop a vaccine capable of providing broad protection. Apollo’s investigational vaccine uses a conserved protein antigen combined with Th1-polarizing adjuvants to stimulate broad cellular immune responses. In the Phase 1 study, a single dose generated rhinovirus-specific immunity, including seroconversion and Th1-skewed cellular responses. Importantly, investigators observed T-cell responses against peptide pools representing all three rhinovirus species, providing early human evidence that the vaccine may generate cross-species immune coverage.
Phase 1 Data Support Cross-Reactive Immune Response
Part A evaluated three single-dose levels of APL-10456 in healthy adults aged 18 to 54 years, with the overall Phase 1 program enrolling 144 participants. The initial safety findings showed that APL-10456 was generally well-tolerated, with the most frequently reported adverse events consisting of mild-to-moderate injection-site reactions. No serious adverse events were reported in Part A. From an immunogenicity perspective, the most important finding was the ability of a single administration to induce broad cross-rhinovirus cellular immunity. The observed responses across RV-A, RV-B and RV-C are particularly relevant because a successful pan-rhinovirus vaccine will need to address the pathogen’s substantial strain diversity rather than provide protection against only a limited number of circulating strains. Apollo said the findings are consistent with earlier preclinical research showing broad cross-strain immunity and rapid clearance of heterotypic rhinovirus.
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Apollo Plans Phase 2 COPD Exacerbation Study
The program now moves toward additional clinical evaluation in the population most affected by rhinovirus-driven respiratory disease. Part B of the Phase 1 trial, evaluating a two-dose regimen in adults aged 55 years and older, has also completed enrollment and dosing, with additional data expected in Q4 2026. Apollo plans to use the combined Phase 1 findings to support initiation of a randomized, double-blind, placebo-controlled Phase 2 trial in the first half of 2027, focused on preventing COPD exacerbations. Rhinovirus is a major driver of exacerbations in people with COPD and asthma and is estimated to contribute to approximately 25% to 50% of COPD exacerbation events. By targeting the virus before it triggers respiratory deterioration, APL-10456 could represent a fundamentally different preventive strategy for chronic respiratory disease. The next major catalyst for the program will be the Q4 2026 Part B data, followed by Phase 2 development planned for 2027.
Source:Apollo Therapeutics,press relese
