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ClinicalTrials.gov 24,857 recruiting now free trial finder

Find a clinical trial that's recruiting now

Search 24,857 actively recruiting US clinical trials by condition, drug, or state, each entry links straight to its NIH ClinicalTrials.gov record so you can check eligibility and contact the study team.

24,857
trials recruiting now
14%
of all US trials open to enrollment
52
states with recruiting sites

A trial is listed as recruiting when its sponsor has marked it open to new participants on the public registry. Type a condition or drug name (for example, "breast cancer" or "pembrolizumab") to narrow the list, and add a state to find studies with a site near you. Results are ordered with the most relevant recruiting studies first; each card shows the study phase and enrollment target, and opens the full record, including eligibility criteria and contact details, on ClinicalTrials.gov.

Showing the 40 largest recruiting trials by target enrollment in California. Use the search field to focus on a condition or drug.

Recruiting 20,000,000 participants

IRIS Registry: Intelligent Research in Sight Registry

American Academy of Ophthalmology

NCT02485847

Recruiting 5,000,000 participants

The Pediatric Anesthesia Quality Improvement Project

The Society for Pediatric Anesthesia

NCT00674388

Recruiting 960,000 participants

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

Kaiser Permanente

NCT06029933

Recruiting 500,000 participants

Parkinson Progression Marker Initiative Online (PPMI Online)

Michael J. Fox Foundation for Parkinson's Research

NCT05065060

Recruiting NA 500,000 participants

Data Collection and Evaluation of OptiBP Under Investigational Use

Biospectal

NCT06017687

Recruiting Phase 4 400,000 participants

A Trial Comparing Screening Mammography With and Without Assistance From Artificial Intelligence for Breast Cancer Detection and Recall Rates in Adult Patients

Jonsson Comprehensive Cancer Center

NCT06934239

Recruiting 339,000 participants

Treating Genital Herpes Infection to Reduce Racial Disparities in the Risk of Severe Maternal Morbidity

Kaiser Permanente

NCT05429346

Recruiting NA 301,201 participants

Provider Recommendation and HPV Vaccination

Kaiser Permanente

NCT05365048

Recruiting NA 300,000 participants

Arrival Time Implementation

University of California, Los Angeles

NCT07314697

Recruiting 200,000 participants

Alzheimer Prevention Trials (APT) Webstudy

University of Southern California

NCT03638583

Recruiting NA 180,000 participants

TabCAT Brain Health Assessment in Primary Care

University of California, San Francisco

NCT06090578

Recruiting 150,000 participants

Improving Safety and Quality of Tracheal Intubation Practice in Pediatric ICUs

Children's Hospital of Philadelphia

NCT02493478

Recruiting 130,000 participants

Surveillance Colonoscopy in Older Adults: The SurvOlderAdults Study

VA Office of Research and Development

NCT05994482

Recruiting NA 119,680 participants

Implementing Scalable, PAtient-centered, Team-based, Technology-enabled Care for Adults With Type 2 Diabetes (iPATH)

Stanford University

NCT06251323

Recruiting NA 102,000 participants

Rady Children's Institute Genomic Biorepository

Rady Pediatric Genomics & Systems Medicine Institute

NCT02917460

Recruiting NA 100,500 participants

The Long COVID-19 Wearable Device Study

Scripps Translational Science Institute

NCT05741112

Recruiting 100,000 participants

Research Framework Exploring Sleep Health

Scripps Translational Science Institute

NCT05197738

Recruiting 100,000 participants

US National OCS Heart Perfusion (OHP) Registry

TransMedics

NCT05915299

Recruiting 100,000 participants

Product Surveillance Registry

Medtronic

NCT01524276

Recruiting 100,000 participants

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

Scripps Translational Science Institute

NCT04336020

Recruiting 100,000 participants

Protocol for Collecting, Banking and Distributing Human Tissue Samples: St. Jude Children's Research Hospital Tissue Resources Core Facility

St. Jude Children's Research Hospital

NCT01354002

Recruiting 100,000 participants

US National OCS Liver Perfusion (OLP) Registry

TransMedics

NCT05940857

Recruiting 100,000 participants

Epilepsy Learning Healthcare System (ELHS)

Epilepsy Foundation of America

NCT06265103

Recruiting NA 100,000 participants

Women Informed to Screen Depending on Measures of Risk (Wisdom Study)

University of California, San Francisco

NCT02620852

Recruiting NA 100,000 participants

MyGeneRank: A Digital Platform for Next-Generation Genetic Studies

Scripps Translational Science Institute

NCT03277365

Recruiting 100,000 participants

POWERMOM, A Healthy Pregnancy Research Community

Scripps Translational Science Institute

NCT03085875

Recruiting 99,999 participants

A Multicenter Access and Distribution Protocol for Unlicensed Cryopreserved Cord Blood Units (CBUs)

Center for International Blood and Marrow Transplant Research

NCT01351545

Recruiting NA 80,800 participants

Building Resilience at Schools: Emotional and Biological Assessment and Treatment of Traumatic Stress

Stanford University

NCT05701111

Recruiting 80,000 participants

Generic Database of Very Low Birth Weight Infants

NICHD Neonatal Research Network

NCT00063063

Recruiting 75,000 participants

TrialNet Pathway to Prevention of T1D

University of South Florida

NCT00097292

Recruiting 75,000 participants

Project: Every Child for Younger Patients With Cancer

Children's Oncology Group

NCT02402244

Recruiting 68,000 participants

Follow-up Visit of High Risk Infants

NICHD Neonatal Research Network

NCT00009633

Recruiting 63,200 participants

Direct-to-patient Teledermatology and Computer-assisted Diagnosis

VA Office of Research and Development

NCT05128006

Recruiting NA 60,200 participants

Village-Integrated Eye Worker Trial II

University of California, San Francisco

NCT03752840

Recruiting 60,000 participants

Stroke Recovery Initiative - Registry for Stroke Research Studies

University of California, San Francisco

NCT03318432

Recruiting NA 50,000 participants

Galleri® in the Medicare Population.

GRAIL

NCT05673018

Recruiting 50,000 participants

A DirEct to PatieNt Study in Chronic Pain

Boston Scientific Corporation

NCT05515341

Recruiting 50,000 participants

SYNERGY-AI: Artificial Intelligence Based Precision Oncology Clinical Trial Matching and Registry

Massive Bio

NCT03452774

Recruiting 50,000 participants

Childhood Cancer Survivor Study

St. Jude Children's Research Hospital

NCT01120353

Recruiting NA 45,450 participants

Clean Trial - Chlorination to Reduce Enteric and Antibiotic Resistant Infections in Neonates

University of California, Berkeley

NCT06824350

Source: ClinicalTrials.gov (NIH/NLM) ClinicalTrials.gov AACT registry · 2026 Recruiting status is reported by each study's sponsor and mirrored from the public registry. Always confirm current eligibility and status on ClinicalTrials.gov before contacting a study.

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