Recruiting Studies
Advanced SearchData: ClinicalTrials.gov · Source of record for eligibility and locations
Top Cities for Vaccine Clinical Trials
Vaccine clinical trials are recruiting across 208 cities. Here are the cities with the most active studies:
Vaccine Trial Phases
61 research organizations are sponsoring vaccine trials.
About Vaccine
Vaccines are biological preparations that provide active immunity against specific infectious diseases. Clinical trials for vaccines test safety, immunogenicity, and efficacy in preventing disease. Current research includes vaccines for cancer, HIV, malaria, and improved formulations for existing diseases.
Clinical trials are advancing new treatments for vaccine. Currently, 100 studies are recruiting a combined 1,786,277 participants across the United States. Research is being conducted by 61 organizations including Kaiser Permanente, University of California, Los Angeles, Yale University and 58 others.
2026 Vaccine Research Landscape
As of August 2026, the vaccine clinical trial landscape includes 100 actively recruiting studies across 208 cities in the United States. These studies are collectively seeking 1,786,277 participants, with an average enrollment target of 17,863 per study.
The research spans multiple phases of development: 34 studies are in PHASE2, 24 studies are in PHASE1, 17 studies are in PHASE3, 15 studies are in NA, 12 studies are in PHASE4, 1 study is in EARLY_PHASE1. The presence of Phase 3 trials indicates that some vaccine treatments are in late-stage testing and may be approaching regulatory review.
Research is being led by 61 different organizations, including Kaiser Permanente, University of California, Los Angeles, Yale University, Pfizer, Masaryk University, and 56 others. The large number of sponsors reflects significant research interest and investment in vaccine treatment advancement.
Geographically, vaccine trials are most concentrated in Atlanta, Georgia (10 trials); Houston, Texas (10 trials); Los Angeles, California (9 trials); New York, New York (9 trials); Miami, Florida (9 trials) and 7 other cities.
Featured Vaccine Studies
Highlighted recruiting studies for vaccine, selected by enrollment size and research scope.
Fluad vs. Fluzone High-Dose Vaccine Effectiveness Among Adults ≥65 Years
This study will evaluate the relative vaccine effectiveness of quadrivalent adjuvanted inactivated influenza vaccine (aIIV4) versus quadrivalent high-dose inactivated influenza vaccine (HD-IIV4) in preventing polymerase chain reaction (PCR)-confirmed influenza and influenza-related outcomes in adults ≥65 years of age during the 2023/24, 2024/25, and 2026/27 influenza seasons. The study is an obser...
The STOP-HPV Scale Up Study
Human papillomavirus (HPV) causes 35,900 US cancer cases per year, 4,000 deaths, and $4 billion in can In this study, the investigators will conduct a 3-arm clustered randomized controlled trial (RCT) in an estimated 72 practices from up to 8 health systems to evaluate the effectiveness and cost effectiveness of two potentially scalable implementation strategies (based on prior work) to increase t...
Addressing Vaccine Acceptance in Carceral Settings Through Community Engagement
The goal of this study is to reduce morbidity and mortality from COVID-19 amongst people who are detained in and work in correctional facilities. The overall objective is to identify feasible and effective interventions to improve vaccine uptake in correctional facilities and study the effectiveness of these interventions through rapid cycle, cluster randomized trials in the Pennsylvania prison sy...
Frequently Asked Questions About Vaccine Clinical Trials
Are there vaccine clinical trials near me?
Yes, there are 100 vaccine clinical trials currently recruiting across 208+ cities in the United States, including Atlanta, Georgia; Houston, Texas; Los Angeles, California. Browse the studies above to find one at a location convenient for you.
How do I join a vaccine clinical trial?
To join a vaccine clinical trial: 1) Browse the available studies on this page, 2) Click on a study that interests you, 3) Check the study locations to find a site near you, 4) Review the eligibility criteria, and 5) Contact the study site or complete the eligibility form. The process is free and you can withdraw at any time.
Are vaccine clinical trials free?
Yes, participation in vaccine clinical trials is free. Study-related treatments, medical tests, and doctor visits are provided at no cost to participants. Many studies also offer compensation for your time and travel expenses.
What types of vaccine treatments are being studied?
Current vaccine clinical trials are testing a range of approaches across PHASE2 (34 studies), PHASE1 (24 studies), PHASE3 (17 studies), NA (15 studies), PHASE4 (12 studies), EARLY_PHASE1 (1 study). These include new drugs, combination therapies, medical devices, and other interventions sponsored by 61 research organizations.
Is it safe to participate in vaccine clinical trials?
Clinical trials are carefully regulated by the FDA and institutional review boards (IRBs). All trials must follow strict safety protocols, and participants receive close medical monitoring throughout the study. You can withdraw from a trial at any time without penalty.
Data updated August 30, 2026 from ClinicalTrials.gov
About This Data
Data: ClinicalTrials.gov · Source of record for eligibility and locations
Clinical trial information on this page is sourced from ClinicalTrials.gov, a service of the U.S. National Institutes of Health (NIH) and National Library of Medicine (NLM). Study data is refreshed every hour to ensure accuracy.
Medical Disclaimer: The information provided on this page is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider before making decisions about clinical trial participation or changes to your treatment plan.
Page reviewed by the HelloStudys Research Team · Last updated August 30, 2026 · Data from ClinicalTrials.gov