Medical Information Only. Consult your healthcare provider before considering clinical trial enrollment.
Influenza clinical trials
Every US clinical trial registered for Influenza — phase mix, recruiting status, and the sponsors running them, straight from the NIH ClinicalTrials.gov registry.
157 US clinical trials · 27 currently recruiting
The research picture
Influenza has 157 registered US clinical trials, 27 of them open to new participants right now — about 17% of the total.
- 27
- recruiting participants now
- 17%
- of trials open to enrollment
- 42
- in Phase 3–4 (later-stage)
- 36
- top sponsor: National Institute of Allergy and Infectious Diseases (NIAID)
Counts reflect the public ClinicalTrials.gov registry as last mirrored by PlainTrial. Status and phase are reported by each study's sponsor. This is reference information, not medical advice.
Active & Recent Trials
Fluad vs. Fluzone High-Dose Vaccine Effectiveness Among Adults ≥65 Years
Kaiser Permanente
NCT06029933
Clinical Outcomes and Pharmacotherapy Effectiveness in the VA Health Care System (COPE-VA)
VA Office of Research and Development
NCT06160128
The DETECT(Digital Engagement & Tracking for Early Control, & Treatment) Study
Scripps Translational Science Institute
NCT04336020
The INFLUENTIAL Trial- Evaluation of National Inpatient Influenza Vaccination Program
University of Colorado, Denver
NCT05832307
Respiratory Virus Sampling and Repository
National Institute of Allergy and Infectious Diseases (NIAID)
NCT05266222
Influenza & COVID-19 Obstetric and Perinatal Epidemiology Study in India
Boston University
NCT06168019
Screening for LID Clinical Studies Unit Healthy Volunteer Protocols
National Institute of Allergy and Infectious Diseases (NIAID)
NCT01386424
Dime La VerDAD: Verify, Debunk, and Disseminate
University of Chicago
NCT06417762
Influenza Immunization in Adults Over Age 75
Johns Hopkins University
NCT02200276
Observational Digital Biomarker Discovery in Respiratory Virus Challenge Studies
National Institute of Allergy and Infectious Diseases (NIAID)
NCT04772170
A Surveillance Study of Susceptibility to Baloxavir Marboxil in Pediatric Participants With Influenza and Transmission of Influenza to Household Contacts
Hoffmann-La Roche
NCT06094010
High vs.Standard Dose Influenza Vaccine in Pediatric Solid Organ Transplant (SOT) Recipients
National Institute of Allergy and Infectious Diseases (NIAID)
NCT05947071
Immune Defense Protein Impact On Respiratory Immune Outcomes
Quantec
NCT07431840
Dissecting Human Immune Responses to Infection With Influenza or SARS-CoV-2
Washington University School of Medicine
NCT06848309
High vs. Standard Dose Influenza Vaccine in Lung Allograft Recipients
Vanderbilt University Medical Center
NCT05215327
pH1N1 Blinded Challenge Study
National Institute of Allergy and Infectious Diseases (NIAID)
NCT07110532
Natural History of Systemic and Nasal Mucosal Immunity to Influenza and SARS-CoV-2 in Adults After Vaccination
National Institute of Allergy and Infectious Diseases (NIAID)
NCT04794829
Systems Investigation of Vaccine Responses in Aging and Frailty
Yale University
NCT05291676
Bone Marrow and Peripheral Blood Immune Responses Study
Emory University
NCT05616546
Influenza Human Challenge Model
Emory University
NCT05332899
First-in-Human Study of VNT-101: Safety, Tolerability, and Pharmacokinetics
National Institute of Allergy and Infectious Diseases (NIAID)
NCT07169318
High vs. Standard Dose Influenza Vaccines in Lung Transplant (Repeater)
Vanderbilt University Medical Center
NCT07192458
Baloxavir and Oseltamivir for the Treatment of Severe Influenza Infection in Immunocompromised Patients
M.D. Anderson Cancer Center
NCT04712539
Comparative Immunogenicity of Respiratory Virus Vaccines (CIRV2) Study
Henry M. Jackson Foundation for the Advancement of Military Medicine
NCT07287137
B Cell and Antibody Response to Seasonal Influenza Vaccines in Younger and Older Adults
University of Alabama at Birmingham
NCT04101838
A/Texas Flu Challenge
Emory University
NCT06753474
H5N1 Milk Detection Study
Emory University
NCT06850298
Kaiser Permanente VACCination Improvement With Nudge-based CardiovAscular Targeted Engagement
Kaiser Permanente
NCT06571747
Kaiser Colorado Flu Nudge
Kaiser Permanente
NCT07372950
A Study to Evaluate the Safety and Efficacy of CD388 for Prevention of Influenza
Cidara Therapeutics
NCT07159763
Influenza IMPRINT Cohort: Defining the Impact of Initial Influenza Exposure on Immunity in Infants
Children's Hospital Medical Center, Cincinnati
NCT05436184
A Study on the Safety and Immunogenicity of Hexavalent Influenza mRNA Vaccine in Adult Participants 50 Years of Age and Older
Sanofi Pasteur, a Sanofi Company
NCT06744205
Longitudinal At Home Smell Testing to Detect Infection by SARS-CoV-2
Massachusetts General Hospital
NCT05040659
A Study to Look at the Health Outcomes of Patients With COVID-19 and Influenza
Pfizer
NCT05160636
High vs. Standard Dose Influenza Vaccine in Adult SOT Recipients
Vanderbilt University Medical Center
NCT04613206
SARS-CoV-2/COVID-19 Study of Next Generation Non-Invasive Passive Detection Technologies
The Geneva Foundation
NCT05765396
Association Between Gut Microbiome and Dietary Determinants and Vaccine Response
M.D. Anderson Cancer Center
NCT05239403
A Study to Evaluate the Safety and Immunogenicity of Two Doses of DCVC H1 HA mRNA-LNP in Healthy Adults
National Institute of Allergy and Infectious Diseases (NIAID)
NCT05945485
Impact of High Dietary Fiber on Microbiome and Vaccine Responses
M.D. Anderson Cancer Center
NCT05565586
Exercise and COVID-19 Viral T-cell Immunity
University of Arizona
NCT05019456
Pilot Influenza Challenge Study
Daniel Hoft, MD, PhD
NCT07063849
Mail Outreach To Increase Vaccination Acceptance Through Engagement
Brigham and Women's Hospital
NCT02243774
Surveillance Study to Assess the Safety of Flublok Quadrivalent (Influenza Vaccine) in Pregnant Women and Their Offspring
Sanofi Pasteur, a Sanofi Company
NCT04460781
Patient Portal Flu Vaccine Reminders (RCT 6)
University of California, Los Angeles
NCT06062264
Efficacy Study of Two Influenza Vaccines and Placebo in Healthy Adult Subjects
Novartis Vaccines
NCT00630331
Efficacy, Safety, and Immunogenicity of a Plant-Derived Quadrivalent Virus-Like Particles (VLPs) Influenza Vaccine in Adults
Medicago
NCT03301051
Project IMPACT Immunizations (IMProving America's Communities Together) Scaled Demonstration
American Pharmacists Association Foundation
NCT03372967
Study of CD388 for the Prevention of Influenza in Subjects Not at Risk for Influenza Complications
Cidara Therapeutics
NCT06609460
Immunogenicity & Safety of GSK's Influenza Vaccine 1557484A Given to Adults Aged ≥18 Years
GlaxoSmithKline
NCT00616928
Study to Evaluate Impact of School-based Influenza Vaccination on School Populations
Children's Hospital Los Angeles
NCT00844051
Study of Quadrivalent Influenza Vaccine Among Children
Sanofi Pasteur, a Sanofi Company
NCT01240746
Safety, Immunogenicity, and Relative Efficacy of H1N1 Vaccines in Adults Aged 18 Years and Older
GlaxoSmithKline
NCT00979602
Adult Influenza Vaccination Text Message Reminders With Electronic Health Record Alerts
Columbia University
NCT02284594
REDucing Influenza Among University Students, University of California at Berkeley
Centers for Disease Control and Prevention
NCT00448773
A Study to Learn About How the Flu and COVID-19 Vaccines Act in Healthy People
BioNTech SE
NCT06821061
Comparison of the Safety of Flublok® Versus Licensed IIV in Healthy, Medically Stable Adults ≥ 50 Years of Age
Protein Sciences Corporation
NCT01825200
A Study of mRNA-based Influenza and SARS-CoV-2 (COVID-19) Multi-component Vaccines in Healthy Adults
ModernaTX
NCT05827926
A Study of Exclusion Criteria in a University Population
University of Michigan
NCT01472536
Safety and Immunogenicity of A/H1N1-SOIV (Swine Flu) Vaccine With and Without Adjuvant in Children (3 to < 9 Years)
Novartis Vaccines
NCT00972816
Safety and Immunogenicity of Flublok Quadrivalent vs IIV4 in Adults 18-49 Years of Age
Protein Sciences Corporation
NCT02290509
Safety and Immunogenicity of H1N1 Vaccines in Adults Aged 18 Years and Older
GlaxoSmithKline
NCT00985088
Study to Evaluate Immunogenicity and Safety of a High-Dose Influenza Vaccine in Adults 50 Through 64 Years of Age
Sanofi Pasteur, a Sanofi Company
NCT06641180
Comparing the Efficacy, Safety, and Tolerability of Combination Antivirals (Amantadine, Ribavirin, Oseltamivir) Versus Oseltamivir for the Treatment of Influenza in Adults at Risk for Complications
National Institute of Allergy and Infectious Diseases (NIAID)
NCT01227967
Sanofi H1N1 + TIV - Adults and Elderly
National Institute of Allergy and Infectious Diseases (NIAID)
NCT00943878
Safety and Immunogenicity of H1N1 Vaccine With Trivalent Inactivated Seasonal Influenza Vaccine in Adults
GlaxoSmithKline
NCT00985673
Safety and Reactogenicity of FluBlok and Comparison of Immunogenicity, Efficacy and Effectiveness Against TIV
Protein Sciences Corporation
NCT00539864
A Study of Influenza Virus Vaccines in Children and Adults
Sanofi Pasteur, a Sanofi Company
NCT00988143
H5 Vaccine Alone or With Aluminum Hydroxide in Elderly Adults
National Institute of Allergy and Infectious Diseases (NIAID)
NCT00294099
Study on Two Adjuvanted Dose Levels of Panblok H7+MF59 Compared for Immunogenicity and Safety With an Unadjuvanted Dose of Panblok H7 in Participants 18 Years of Age and Older
Sanofi Pasteur, a Sanofi Company
NCT05608005
Sanofi Pasteur, TIV + H1N1, Pediatric Population
National Institute of Allergy and Infectious Diseases (NIAID)
NCT00943202
Dose-Finding Study of Favipiravir in the Treatment of Uncomplicated Influenza
MDVI
NCT01068912
Study of Inactivated, Split-Virion Influenza Vaccine Compared With Standard Fluzone Vaccine in Infants and Children
Sanofi
NCT00391391
H5N1 (Clade 2) Vaccination of Adults and Elderly
National Institute of Allergy and Infectious Diseases (NIAID)
NCT00680069
Fluarix/ FluLaval/ Fluarix Quadrivalent/ FluLaval Quadrivalent Vaccine Pregnancy Registry
GlaxoSmithKline
NCT02148211
Xofluza-Wearables Feasibility-Study
Children's Hospital of Philadelphia
NCT06161454
CSL H1N1 Influenza Vaccine Administered at Two Dose Levels in Adult and Elderly Populations
National Institute of Allergy and Infectious Diseases (NIAID)
NCT00943488
Study to Assess Efficacy and Safety of Baloxavir Marboxil In Combination With Standard-of-Care Neuraminidase Inhibitor In Hospitalized Participants With Severe Influenza
Hoffmann-La Roche
NCT03684044
Reverse Genetic H9N2 Influenza Vaccine Study in Adults
Alachua Government Services
NCT01320696
Trial to Assess the Shedding,Immunogenicity, and Safety of FluMist Administered to Healthy Individuals 5-49 Years of Age
MedImmune
NCT00192140
Cell-Mediated Immune Responses to Influenza A/H5N1 Vaccine
National Institute of Allergy and Infectious Diseases (NIAID)
NCT00311727
H5 Booster After a Two Dose Schedule
National Institute of Allergy and Infectious Diseases (NIAID)
NCT00240968
Audio Data Collection for Identification and Classification of Coughing
HealthMode
NCT04326309
A Study to Evaluate the Safety of HIN1 Monovalent Vaccine (MEDI3414) in Children 2 to 17 Years of Age
MedImmune
NCT00946101
Study to Evaluate Immunogenicity and Safety of GlaxoSmithKline (GSK) Biologicals' Quadrivalent Influenza Vaccine GSK2282512A When Administered to Children From 6 to 35 Months of Age
GlaxoSmithKline
NCT01974895
Efficacy and Safety of Norketotifen in Uncomplicated Influenza-like Illness
Emergo Therapeutics
NCT04610047
Study to Evaluate the Safety of 1 New 6:2 Influenza Virus Reassortant in Adults for the 2016-2017 Season
MedImmune
NCT02743117
Study to Evaluate the Safety of 3 New 6:2 Influenza Virus Reassortants in Adults for the 2015-2016 Season
MedImmune
NCT02473510
Study to Evaluate the Safety of 1 New 6:2 Influenza Virus Reassortant in Adults for the 2017-2018 Season
MedImmune
NCT03158038
Study to Evaluate the Safety of a Bivalent Vaccine of New 6:2 Influenza Virus Reassortants in Healthy Adults
MedImmune
NCT00125944
Study of Fluzone® Influenza Virus Vaccine 2011-2012 Formulation (Intramuscular Route) Among Adults
Sanofi Pasteur, a Sanofi Company
NCT01430819
H5N1 Mix and Match With MF59
National Institute of Allergy and Infectious Diseases (NIAID)
NCT01317745
Comparison of Flu Vaccine Doses in Children
National Institute of Allergy and Infectious Diseases (NIAID)
NCT01164553
Gene Signatures of Influenza Vaccine Responses in Older Adults
Mayo Clinic
NCT03603509
Safety and Immunogenicity of Fluzone® Quadrivalent and Fluzone® High-Dose, Influenza Vaccines
Sanofi Pasteur, a Sanofi Company
NCT03308825
Influenza Vaccine Randomized Educational Trial: Adult
Columbia University
NCT02907645
Safety, Reactogenicity and Immunogenicity of Flublok Quadrivalent (Recombinant Influenza Vaccine,Seasonal Formulation)
Protein Sciences Corporation
NCT01959945
Immunogenicity and Safety of Different Doses of Fluzone® Influenza
National Institute of Allergy and Infectious Diseases (NIAID)
NCT00253734
Study of Fluzone® Quadrivalent, Fluzone® Intradermal Quadrivalent, and Fluzone® High-Dose, Influenza Vaccines in Adults
Sanofi Pasteur, a Sanofi Company
NCT02563093
Cellular and Molecular Characterization of the Immune Response in Healthy NIH Employees atBaseline, and After Immunization With the H1N1 or Seasonal Influenza Vaccines
National Heart, Lung, and Blood Institute (NHLBI)
NCT01191853
Safety and Immune Response Study of GSK Biologicals' Influenza Virus Vaccine 1388442A Compared With Fluarix
GlaxoSmithKline
NCT00693706
Phase Distribution
| Phase | Trial count |
|---|---|
| Phase 1 | 42 |
| Phase 2 | 31 |
| Phase 3 | 17 |
| Phase 4 | 25 |
Top Sponsors
Source: ClinicalTrials.gov, National Library of Medicine. Data is informational only.
Reading the Influenza Trial Landscape
ClinicalTrials.gov lists 157 US studies indexed under Influenza, and 27 of those are currently open to recruitment — roughly 17% of the total volume on the registry. That ratio is a useful proxy for activity level: a high share of recruiting studies often signals that research interest is current and that new enrollment opportunities are appearing, while a low share typically means the field is dominated by completed or follow-up work where most participant spots have already been filled. These counts reflect the public registry only and include studies at every stage of design, so they should be read as an index of research attention rather than as a measure of treatment availability.
The phase distribution for Influenza shows 42 late-stage studies (Phase 3 and Phase 4 combined) alongside 73 earlier-phase entries (Phase 1 through Phase 2). Phase 1 and Phase 2 studies focus on early safety signals, dosing, and preliminary effect, while Phase 3 studies are typically the larger efficacy and safety trials submitted toward regulatory review, and Phase 4 studies follow approved interventions in real-world use. A condition weighted toward later phases often reflects a mature research pipeline with several interventions already close to or past approval, whereas a heavier early-phase tilt suggests the field is still exploring new mechanisms and candidate approaches.
Top sponsor activity for Influenza is led by National Institute of Allergy and Infectious Diseases (NIAID) with 36 indexed trials, alongside 9 other organizations in the top contributor list. The list on this page surfaces up to 100 of the most relevant recent and active entries, ordered with recruiting studies first so practical options are visible. All figures are derived from the public ClinicalTrials.gov dataset maintained by the National Library of Medicine and are reproduced here for reference. Inclusion of a trial, sponsor, or intervention on this page is neither an endorsement nor a recommendation — eligibility, protocol changes, and site-level status can shift frequently, so always verify current details on ClinicalTrials.gov and consult a qualified healthcare provider before acting on anything you see here.
Frequently Asked Questions
How many clinical trials are there for Influenza?
PlainTrial tracks 157 US clinical trials for Influenza, of which 27 are currently recruiting participants. Data sourced from ClinicalTrials.gov.
How do I find a recruiting trial for Influenza?
Use the trial list above filtered by "Recruiting" status, or visit our trial finder at /recruiting to search by condition and state. Always discuss trial participation with your healthcare provider before enrolling.
Is this data current?
Data is sourced from ClinicalTrials.gov and reflects our most recent data pull. Trial status may have changed since then. Always verify current information at ClinicalTrials.gov before making decisions about participation.
Related
Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from ClinicalTrials.gov (National Library of Medicine). Consult a qualified professional before making decisions based on this data.
Read our methodology — how this data is sourced, computed, and verified.
Source: ClinicalTrials.gov (NIH/NLM) ClinicalTrials.gov AACT registry · 2026 Trial counts and statuses sourced from ClinicalTrials.gov. Sponsor counts include both industry and federal/academic sponsors.