Browse by Phase
N/A (Early Phase / Not Applicable) Clinical Trials
Browse currently recruiting N/A (Early Phase / Not Applicable) clinical trials registered on ClinicalTrials.gov.
Total Trials
6,771
Recruiting Now
6,771
Top Conditions in N/A (Early Phase / Not Applicable)
Frequently Asked Questions — N/A (Early Phase / Not Applicable) Trials
What does "N/A" mean for a clinical trial phase?
"N/A" or "Not Applicable" in the phase field indicates the trial does not follow the traditional Phase 1–4 drug development pathway. This applies to observational studies, epidemiological research, behavioral interventions, device studies, or exploratory work not yet assigned a formal phase. These studies are still registered on ClinicalTrials.gov and follow IRB-approved protocols.
Are N/A phase trials safe to participate in?
N/A phase trials encompass a wide range of study types, many involving minimal risk—such as observational studies, questionnaire-based research, or registry enrollment. Some may involve investigational devices or early-stage interventions. Review the trial's protocol, risks and benefits section, and informed consent documents carefully before enrolling. All ClinicalTrials.gov-registered studies must comply with applicable safety oversight requirements.
How do I find N/A phase trials for my condition?
Browse ClinicalMetric by condition to find all trials—regardless of phase—that are recruiting for a specific disease. Many N/A phase trials are observational or behavioral studies with fewer eligibility restrictions than phase-designated drug trials, making them more accessible to a broader range of participants.
Active N/A (Early Phase / Not Applicable) Studies
NCT07735286 N/A
Recruiting
Automating Tobacco Cessation in Primary Care
Condition
Tobacco Use
Enrollment
4,800 pts
Location
United States
Sponsor
University of Pennsylvania
NCT06248073 N/A
Recruiting
Effectiveness of Online Program and Task-related Training for Parkinson's Diseas...
Condition
Parkinson Disease
Enrollment
100 pts
Location
Taiwan
Sponsor
Chang Gung University
NCT05636969 N/A
Recruiting
Multimodal Prehabilitation in Patients With Lung Cancer Undergoing Neoadjuvant T...
Condition
Non Small Cell Lung Cancer
Enrollment
60 pts
Location
Spain
Sponsor
Hospital Clinic of Barcelona
NCT05838183 N/A
Recruiting
Interstitial Lung Disease and Obstructive Sleep Apnea
Condition
ILD OSA
Enrollment
70 pts
Location
China
Sponsor
Dan Liu
NCT06950983 N/A
Recruiting
Navigating Financial and Health-Related Social Needs in Adolescent and Young Adu...
Condition
Cancer in Adolescence
Enrollment
120 pts
Location
United States
Sponsor
Columbia University
NCT05763966 N/A
Recruiting
Uppsala Psychosis Cohort
Condition
Schizophrenia; Psychosis
Enrollment
120 pts
Location
Sweden
Sponsor
Uppsala University
NCT06696222 N/A
Recruiting
Fermented Vegan Optimized Diet in Health and Colitis
Condition
Healthy Volunteers
Enrollment
240 pts
Location
Sweden
Sponsor
Region Skane
NCT07584122 N/A
Recruiting
Improving Access to PrEP (HIV Prevention Medication) for People in Underserved A...
Condition
HIV Infections
Enrollment
400 pts
Location
Brazil
Sponsor
Oswaldo Cruz Foundation
NCT03883022 N/A
Recruiting
Vancomycin Powder Combined With Autogenous Bone Graft as a Prevention for Post-o...
Condition
Spinal Fusion
Enrollment
400 pts
Location
Taiwan
Sponsor
Taipei Veterans General Hospit
NCT07023510 N/A
Recruiting
The VALVE-AI Trial
Condition
Valvular Heart Disease Patients
Enrollment
8,648 pts
Location
Taiwan
Sponsor
National Defense Medical Cente
NCT06238713 N/A
Recruiting
Extraperitoneal SINgle-port rObotic-assisted Radical Prostatectomy (RARP) Versus...
Condition
Prostate Adenocarcinoma
Enrollment
480 pts
Location
China
Sponsor
Shanghai Changzheng Hospital
NCT07077382 N/A
Recruiting
Pneumoconiosis and Dust Exposure China Cohort
Condition
Pneumoconiosis
Enrollment
2,000 pts
Location
China
Sponsor
China-Japan Friendship Hospita
NCT06781359 N/A
Recruiting
Study on Plasmablastic Lymphoma Patients
Condition
Plasmablastic Lymphoma
Enrollment
200 pts
Location
Italy
Sponsor
Fondazione Italiana Linfomi -
NCT06601179 N/A
Recruiting
Evaluating the Safety and Efficacy of the "HIFU" High-intensity Focused Ultrasou...
Condition
Benign Prostatic Hyperplasia
Enrollment
100 pts
Location
France
Sponsor
EDAP TMS S.A.
NCT06037096 N/A
Recruiting
Implementation of a Structured Post-pulmonary Embolism Follow-up Model
Condition
Pulmonary Embolism
Enrollment
2,000 pts
Location
Denmark
Sponsor
Aalborg University Hospital
NCT07925996 N/A
Recruiting
Dermal Priming in Enhancing Vaccine Immunogenicity
Condition
ANCA Associated Vasculitis (AAV)
Enrollment
28 pts
Location
United Kingdom
Sponsor
Cambridge University Hospitals
NCT07524088 N/A
Recruiting
Contamination of Young Children Hair During Acute Cannabis Intoxication
Condition
Cannabis Intoxication in Children
Enrollment
15 pts
Location
France
Sponsor
University Hospital, Toulouse
NCT06550427 N/A
Recruiting
Early Assessment of Lymphoma Treatment Response Using Phased Variant Analysis Wi...
Condition
Lymphoma
Enrollment
200 pts
Location
Taiwan
Sponsor
National Taiwan University Hos
NCT06618027 N/A
Recruiting
Pragmatic Clinic-Based Trial of a Mindfulness Based Intervention for Mood Concer...
Condition
Type 1 Diabetes (T1D)
Enrollment
200 pts
Location
United States
Sponsor
Children's National Research I
NCT06332573 N/A
Recruiting
Impact of Onco-sexology Support on the Quality of Life of Patients Newly Diagnos...
Condition
Cancer
Enrollment
168 pts
Location
France
Sponsor
Hôpital Européen Marseille
NCT02161783 N/A
Recruiting
Treatment of Graft Failure After Hematopoietic Stem Cell Transplantation
Condition
Primary Graft Failure
Enrollment
50 pts
Location
United States
Sponsor
Masonic Cancer Center, Univers
NCT06049654 N/A
Recruiting
Comparison of Allegra vs Sapien Transcatheter Aortic Valves in Valve-In-Valve In...
Condition
Aortic Valve Stenosis
Enrollment
104 pts
Location
Italy, Spain, United Kingdom
Sponsor
Fundación EPIC
NCT06801366 N/A
Recruiting
VIdeo Clips for Diagnostic Evaluation of Obstructive Sleep Apnea in Children
Condition
Obstructive Sleep Apnea (OSA)
Enrollment
625 pts
Location
Canada
Sponsor
Children's Hospital of Eastern
NCT06222866 N/A
Recruiting
Anticoagulation and Inflammation Monitoring in Patients After Heart and Vascular...
Condition
Heart Surgery
Enrollment
400 pts
Location
Austria
Sponsor
Medical University Innsbruck
NCT07368556 N/A
Recruiting
The Impact of a Nursing Care Program Based on Human Caring Theory on Adolescents...
Condition
Self Harm
Enrollment
48 pts
Location
Turkey (Türkiye)
Sponsor
Akdeniz University
ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer · Last Reviewed: November 2026 · Data Methodology