Clinical Trials / Browse by Phase / N/A (Early Phase / Not Applicable)

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)

Breast Cancer (110) Stroke (104) Obesity (80) Cancer (65) Heart Failure (63) Prostate Cancer (53) Lung Cancer (52) Healthy (51) Depression (49) Hypertension (47)

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

NCT07322523 N/A

Smartwatch Accuracy for Measuring Vitals and Anxiety Before Disc Surgery

Disc Herniations

Turkey (Türkiye)

NCT06367296 N/A

Resistance Exercise Training in the Older Population With Obesity

Universidad de La Frontera

NCT04621396 N/A

The Next Generation Longitudinal Birth Cohort Diabetes Study

Type 2 Diabetes

University of Manitoba

NCT07541196 N/A

PAW-Hydrogel for Chronic Wound Healing

Diabetic Foot Ulcer (DFU)

Benjamín Gonzalo Rodríguez Mén

NCT04817462 N/A

Liver Biopsy In Haemophilia Gene Therapy

Hemophilia B, Severe

University College, London

NCT06802003 N/A

Predicting Acute Exacerbations of COPD Using Wearable Devices and Remote Monitor...

McGill University Health Centr

NCT07168642 N/A

A Type I Hybrid Effectiveness-Implementation Trial of MIO

Substance Use Disorder

Baystate Medical Center

NCT05183542 N/A

SPECT/CT Bone Scan Quantification Surgery

Pseudoarthrosis of Bone

Central Hospital, Nancy, Franc

NCT07449442 N/A

SII Levels Following iPACK Block With Adductor Canal Block in Knee Arthroplasty

Knee Osteoarthritis

Poznan University of Medical S

NCT06576986 N/A

Effect of Synbiotic Supplementation on the Prevention of Mucositis in Cancer Pat...

Colo-rectal Cancer

Federal University of Minas Ge

NCT06955286 N/A

Study on the Incidence of Adrenal Insufficiency After Surgery in Primary Aldoste...

Primary Aldosteronism

NCT06380673 N/A

Stepwise Heat-Denaturated Protein Introduction for Tolerance Induction in Food A...

Universitaire Ziekenhuizen KU

NCT06875869 N/A

Ischemic Compression Technique Versus Jones Technique in Cervicogenic Headache P...

Cervicogenic Headache

Riphah International Universit

NCT06846983 N/A

Peripheral Perfusion Index as an Early Predictor of Successful Caudal Block in P...

Peripheral Perfusion Index

Ain Shams University

NCT07438041 N/A

Linking Youth to Pre-Exposure Prophylaxis (PrEP) Services

NCT04117841 N/A

SCFE Longitudinal International Prospective Registry

Slipped Capital Femoral Epiphyses

University of British Columbia

NCT07692269 N/A

Mindfulness Intervention for Emotional Distress: An EEG Study

Emotional Distress

Peking University

NCT05973383 N/A

Evaluation of a Personalised Digital Intervention (EviBody) for Healthy and Sust...

Sophiahemmet University

NCT06946654 N/A

Geriatric Assessment (GA) for Elderly Patients Undergoing Allo-HSCT

Peking University People's Hos

NCT05267041 N/A

Joint Thoracic Oncology Research Unit of LYon: Lung cancerS DatabaSE (ULYSSE)

Hospices Civils de Lyon

NCT06915454 N/A

High-Resolution PET-CT Imaging for Surgical Margin Visualization

Vanderbilt-Ingram Cancer Cente

NCT06924554 N/A

Motivational Training Program for Pre-service Physical Education Teachers

Teaching Styles

Universidad de Zaragoza

NCT06707454 N/A

Postoperative Clinical and Neurophysiological Assessment of Patients After Open ...

Ain Shams University

NCT07622654 N/A

Effect of Emotion-Focused Acceptance and Commitment Therapy on Obsessive-Compuls...

Turkey (Türkiye)

Mehmet Emrah Karadere

NCT06706154 N/A

Exercise Capacity in Kidney Transplant Recipients

Renal Transplantation

Turkey (Türkiye)

Hacettepe University

Page 8 of 271 — 6,771 trials total

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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