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ClinicalTrials.gov 27 recruiting now early-phase tilt #70 of 28,707 conditions

Influenza: early-phase trial registry

27 of 157 indexed Influenza trials are currently recruiting, with more weight in Phase 1-2.

Corpus placement: #70 of 28,707 conditions by registered trial count.

157 US clinical trials · 27 currently recruiting · #70 of 28,707 conditions by registered trial count

Influenza: 157 US clinical trials tracked, 27 recruiting.

Influenza is the subject of 157 registered US clinical trials on ClinicalTrials.gov, 27 of them currently open to new participants. 42 are in Phase 3-4 (later-stage) and 73 in Phase 1-2 (earlier-stage). The most active sponsor is National Institute of Allergy and Infectious Diseases (NIAID), running 36 of these trials.

Enrollment posture brief

Registry condition influenza

OPEN 27 | RECR 17% | LATE 42 | EARLY 73 | RANK #70 | SPON 36

Nearest open-share peer: Arthritis, Rheumatoid (17% recruiting · 29 trials)

PTSD49.7%Gastric Cancer45.3%Obstructive Sleep Apnea42%Neoplasms31.3%Influenza (this)17%
Open-enrollment share among volume-matched conditions near Influenza

Influenza lists 27 open slots (17% of 157 indexed trials). Peers are matched on registered volume, not therapeutic-area browse lists. How peer matching works →

Key findings

What ClinicalTrials.gov does not surface for Influenza on its own pages , computed from the registry mirror as of 2026-08-08. Each line carries its own denominator so it can be quoted as it stands.

  1. Influenza is recruiting below its size-band peers.

    27 of 157 indexed trials (17.2%) are open to enrollment, against a 37.1% average across 139 conditions with 100+ trials. The peer set uses the same ClinicalTrials.gov-derived counts as this page.

  2. One sponsor concentrates Influenza research.

    National Institute of Allergy and Infectious Diseases (NIAID) accounts for 36 of 157 trials (22.9%). 62 distinct sponsors appear on at least one study for this condition label.

  3. Typical Influenza enrolment sits around 219 participants.

    Median target enrolment is 219 among the 157 trials that report a genuine target (sentinel values excluded). 55 of those (35%) plan for fewer than 100 participants.

  4. Influenza research is mostly interventional.

    134 interventional and 23 observational studies make up this index (85.4% interventional). Study type is sponsor-reported on ClinicalTrials.gov.

Phase 142Phase 231Phase 317Phase 425

Open and recent trials

157 total, page 1 of 4

RECRUITING 960,000 participants

Fluad vs. Fluzone High-Dose Vaccine Effectiveness Among Adults ≥65 Years

Kaiser Permanente

NCT06029933

RECRUITING 400,000 participants

Clinical Outcomes and Pharmacotherapy Effectiveness in the VA Health Care System (COPE-VA)

VA Office of Research and Development

NCT06160128

RECRUITING 100,000 participants

The DETECT(Digital Engagement & Tracking for Early Control, & Treatment) Study

Scripps Translational Science Institute

NCT04336020

RECRUITING NA 22,000 participants

The INFLUENTIAL Trial- Evaluation of National Inpatient Influenza Vaccination Program

University of Colorado, Denver

NCT05832307

RECRUITING 20,000 participants

Respiratory Virus Sampling and Repository

National Institute of Allergy and Infectious Diseases (NIAID)

NCT05266222

RECRUITING 10,000 participants

Influenza & COVID-19 Obstetric and Perinatal Epidemiology Study in India

Boston University

NCT06168019

RECRUITING 5,000 participants

Screening for LID Clinical Studies Unit Healthy Volunteer Protocols

National Institute of Allergy and Infectious Diseases (NIAID)

NCT01386424

RECRUITING NA 1,400 participants

Dime La VerDAD: Verify, Debunk, and Disseminate

University of Chicago

NCT06417762

RECRUITING NA 1,025 participants

Influenza Immunization in Adults Over Age 75

Johns Hopkins University

NCT02200276

RECRUITING 1,000 participants

Observational Digital Biomarker Discovery in Respiratory Virus Challenge Studies

National Institute of Allergy and Infectious Diseases (NIAID)

NCT04772170

RECRUITING Phase 3 750 participants

A Surveillance Study of Susceptibility to Baloxavir Marboxil in Pediatric Participants With Influenza and Transmission of Influenza to Household Contacts

Hoffmann-La Roche

NCT06094010

RECRUITING Phase 2 312 participants

High vs.Standard Dose Influenza Vaccine in Pediatric Solid Organ Transplant (SOT) Recipients

National Institute of Allergy and Infectious Diseases (NIAID)

NCT05947071

RECRUITING NA 300 participants

Immune Defense Protein Impact On Respiratory Immune Outcomes

Quantec

NCT07431840

RECRUITING 300 participants

Dissecting Human Immune Responses to Infection With Influenza or SARS-CoV-2

Washington University School of Medicine

NCT06848309

RECRUITING Phase 2 270 participants

High vs. Standard Dose Influenza Vaccine in Lung Allograft Recipients

Vanderbilt University Medical Center

NCT05215327

RECRUITING Phase 1 180 participants

pH1N1 Blinded Challenge Study

National Institute of Allergy and Infectious Diseases (NIAID)

NCT07110532

RECRUITING 150 participants

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

RECRUITING Phase 2 96 participants

Systems Investigation of Vaccine Responses in Aging and Frailty

Yale University

NCT05291676

RECRUITING Phase 4 90 participants

Bone Marrow and Peripheral Blood Immune Responses Study

Emory University

NCT05616546

RECRUITING Phase 1 80 participants

Influenza Human Challenge Model

Emory University

NCT05332899

RECRUITING Phase 1 78 participants

First-in-Human Study of VNT-101: Safety, Tolerability, and Pharmacokinetics

National Institute of Allergy and Infectious Diseases (NIAID)

NCT07169318

RECRUITING Phase 2 60 participants

High vs. Standard Dose Influenza Vaccines in Lung Transplant (Repeater)

Vanderbilt University Medical Center

NCT07192458

RECRUITING Phase 2 60 participants

Baloxavir and Oseltamivir for the Treatment of Severe Influenza Infection in Immunocompromised Patients

M.D. Anderson Cancer Center

NCT04712539

RECRUITING Phase 4 54 participants

Comparative Immunogenicity of Respiratory Virus Vaccines (CIRV2) Study

Henry M. Jackson Foundation for the Advancement of Military Medicine

NCT07287137

RECRUITING Phase 4 50 participants

B Cell and Antibody Response to Seasonal Influenza Vaccines in Younger and Older Adults

University of Alabama at Birmingham

NCT04101838

RECRUITING Phase 1 50 participants

A/Texas Flu Challenge

Emory University

NCT06753474

RECRUITING NA 30 participants

H5N1 Milk Detection Study

Emory University

NCT06850298

ACTIVE NOT RECRUITING NA 3,668,428 participants

Kaiser Permanente VACCination Improvement With Nudge-based CardiovAscular Targeted Engagement

Kaiser Permanente

NCT06571747

ACTIVE NOT RECRUITING NA 100,000 participants

Kaiser Colorado Flu Nudge

Kaiser Permanente

NCT07372950

ACTIVE NOT RECRUITING Phase 3 7,500 participants

A Study to Evaluate the Safety and Efficacy of CD388 for Prevention of Influenza

Cidara Therapeutics

NCT07159763

ACTIVE NOT RECRUITING 1,500 participants

Influenza IMPRINT Cohort: Defining the Impact of Initial Influenza Exposure on Immunity in Infants

Children's Hospital Medical Center, Cincinnati

NCT05436184

ACTIVE NOT RECRUITING Phase 1 1,162 participants

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

ACTIVE NOT RECRUITING 1,000 participants

Longitudinal At Home Smell Testing to Detect Infection by SARS-CoV-2

Massachusetts General Hospital

NCT05040659

ACTIVE NOT RECRUITING 999 participants

A Study to Look at the Health Outcomes of Patients With COVID-19 and Influenza

Pfizer

NCT05160636

ACTIVE NOT RECRUITING Phase 2 396 participants

High vs. Standard Dose Influenza Vaccine in Adult SOT Recipients

Vanderbilt University Medical Center

NCT04613206

ACTIVE NOT RECRUITING 300 participants

SARS-CoV-2/COVID-19 Study of Next Generation Non-Invasive Passive Detection Technologies

The Geneva Foundation

NCT05765396

ACTIVE NOT RECRUITING 74 participants

Association Between Gut Microbiome and Dietary Determinants and Vaccine Response

M.D. Anderson Cancer Center

NCT05239403

ACTIVE NOT RECRUITING Phase 1 50 participants

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

ACTIVE NOT RECRUITING NA 31 participants

Impact of High Dietary Fiber on Microbiome and Vaccine Responses

M.D. Anderson Cancer Center

NCT05565586

ACTIVE NOT RECRUITING NA 26 participants

Exercise and COVID-19 Viral T-cell Immunity

University of Arizona

NCT05019456

ACTIVE NOT RECRUITING Phase 1 12 participants

Pilot Influenza Challenge Study

Daniel Hoft, MD, PhD

NCT07063849

COMPLETED NA 228,000 participants

Mail Outreach To Increase Vaccination Acceptance Through Engagement

Brigham and Women's Hospital

NCT02243774

COMPLETED 96,175 participants

Surveillance Study to Assess the Safety of Flublok Quadrivalent (Influenza Vaccine) in Pregnant Women and Their Offspring

Sanofi Pasteur, a Sanofi Company

NCT04460781

COMPLETED NA 22,233 participants

Patient Portal Flu Vaccine Reminders (RCT 6)

University of California, Los Angeles

NCT06062264

COMPLETED Phase 3 11,404 participants

Efficacy Study of Two Influenza Vaccines and Placebo in Healthy Adult Subjects

Novartis Vaccines

NCT00630331

COMPLETED Phase 3 10,160 participants

Efficacy, Safety, and Immunogenicity of a Plant-Derived Quadrivalent Virus-Like Particles (VLPs) Influenza Vaccine in Adults

Medicago

NCT03301051

COMPLETED 6,234 participants

Project IMPACT Immunizations (IMProving America's Communities Together) Scaled Demonstration

American Pharmacists Association Foundation

NCT03372967

COMPLETED Phase 2 5,071 participants

Study of CD388 for the Prevention of Influenza in Subjects Not at Risk for Influenza Complications

Cidara Therapeutics

NCT06609460

COMPLETED Phase 3 4,561 participants

Immunogenicity & Safety of GSK's Influenza Vaccine 1557484A Given to Adults Aged ≥18 Years

GlaxoSmithKline

NCT00616928

COMPLETED NA 4,455 participants

Study to Evaluate Impact of School-based Influenza Vaccination on School Populations

Children's Hospital Los Angeles

NCT00844051

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Phase Distribution

PhaseTrial count
Phase 1 42
Phase 2 31
Phase 3 17
Phase 4 25

Named interventions

Most-linked intervention names on Influenza records (sponsor-reported on ClinicalTrials.gov). Counts are trial links, not unique products.

Placebo Biological
7 trials
Fluzone® Biological
5 trials
Oseltamivir Drug
5 trials
Baloxavir Marboxil Drug
5 trials
Placebo Drug
5 trials
Placebo Other
4 trials
Inactivated H1N1 Vaccine Biological
3 trials
GSK2340273A Biological
3 trials

US sites by state

Facility locations filed on Influenza trials. A trial with sites in several states counts in each.

California 45 trials
Maryland 34 trials
Texas 33 trials
Florida 32 trials
Georgia 30 trials
Ohio 29 trials
New York 27 trials
Missouri 26 trials

Source: ClinicalTrials.gov, National Library of Medicine. Data is informational only.

What to do with this Influenza page

157 registered trials, 27 currently recruiting, is a starting point for a conversation, not a diagnosis or a recommendation.

Trial and recruiting counts reflect ClinicalTrials.gov registry status as of the data vintage above; individual trial eligibility and enrollment status can change.

Every figure on PlainTrial is rendered directly from the ClinicalTrials.gov registry, no number is typed in by an editor. This Influenza condition card totals 157 registered trials; most-linked intervention Placebo; top US site state California. See our editorial standards & corrections policy, the methodology behind these numbers, the data changelog, or report a data error.