Infectious Disease Clinical Trials Update: Week 26, 2026

Published June 26, 2026 — 5 trials covered

By Victor Lafforgue, Founder of TrialsAlert. Blog posts are AI-drafted from ClinicalTrials.gov source data and reviewed by the editorial team. See our editorial policy for details.

A Study in India on the Immune Response and Safety of a Respiratory Syncytial Virus (RSV) Older Adults (OA) Vaccine When Given to Older Adults 60 Years of Age and Above and Adults 50-59 Years of Age at Increased Risk (AIR) of Respiratory Syncytial Virus Lower Respiratory Tract Disease (RSV-LRTD)

This Phase 3 study conducted in India tested a new vaccine designed to protect older adults aged 50 and above who are at increased risk of serious respiratory syncytial virus (RSV) infections. With 751 participants, the trial evaluated how well the vaccine triggers an immune response and its safety. If the vaccine proves effective, it could offer an important new way to prevent severe RSV infections in older populations, a group especially vulnerable to complications from this virus.

Study to Learn About Safety, Tolerability, and Immune Response of a Catch-up Pneumococcal Vaccine in Children and Adolescents

This Phase 3 trial is exploring a new pneumococcal vaccine aimed at children and adolescents aged 15 months to 18 years in the US, Puerto Rico, and other countries. The study focuses on whether the vaccine is safe and how well it stimulates the immune system to fight infections caused by pneumococcal bacteria. Success in this trial could lead to broader protection against illnesses like pneumonia and meningitis, which can be serious or even life-threatening in young people.

Lot-to-Lot Consistency Clinical Trial of Recombinant Human Papillomavirus 9-valent (Types 6/11/16/18/31/33/45/52/58) Vaccine (Escherichia Coli)

This Phase 4 trial in China is testing the safety and immune response of a 9-valent human papillomavirus (HPV) vaccine in females aged 18 to 30. The study checks if different production batches of the vaccine work consistently. Confirming this consistency helps ensure that the vaccine remains reliable and effective, which is important for maintaining public trust and increasing access to HPV vaccination, a key measure to prevent HPV-related infections and cancers.

A Study to Evaluate VXA-CoV2-3.3 COVID-19 Vaccine Against Currently Approved/Authorized mRNA COVID-19 Injectable Booster Vaccine in Adults Previously Immunized Against COVID-19 Infection

This Phase 2 study in the United States is comparing an oral COVID-19 vaccine booster to an approved injectable mRNA booster in adults who have already been vaccinated. The oral booster, if effective, could offer a more convenient option that might increase willingness to receive booster doses. Over 5,000 participants are enrolled, and the results will help understand whether a pill-based COVID-19 booster could simplify ongoing vaccination efforts.

A Study of Ziresovir (AK0529) in High-risk Adult With Respiratory Syncytial Virus (RSV) Infection

This Phase 2 trial in China is testing an antiviral drug called Ziresovir in adults at high risk of RSV infection. The study aims to see if the drug can reduce the length and severity of RSV symptoms. If successful, Ziresovir could become a valuable treatment to help vulnerable adults recover faster and avoid complications from RSV infections.

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