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

6,885

Recruiting Now

6,885

Top Conditions in N/A (Early Phase / Not Applicable)

Stroke (113) Breast Cancer (104) Cancer (79) Obesity (68) Prostate Cancer (59) Coronary Artery Disease (51) Heart Failure (50) Cardiovascular Diseases (49) Lung Cancer (49) Healthy (49)

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

NCT06859515 N/A

A Long-term Follow up Study of EXG102-031 in Participants With wAMD

Wet Age-related Macular Degeneration

Guangzhou Jiayin Biotech Ltd

NCT06587308 N/A

Effects of Different Pressure Garments on Upper Extremity Sensorimotor Functions...

Cerebral Vascular Accident (CVA)/Stroke

National University of Malaysi

NCT04575363 N/A

RPSA as a Potential Prognostic Biomarker of Pancreatic Cancer

Pancreatic Ductal Adenocarcinoma (PDAC)

NCT07675863 N/A

Impact of Communication Delays on Anesthesia Response to Medical Emergencies and...

Regional Anesthesia

Nova Scotia Health Authority

NCT04510363 N/A

Optic Nerve Sheath Diameter, Carotid Duplex and Transcranial Duplex as a Prognos...

Neurologic Dysfunction

National Taiwan University Hos

NCT05632887 N/A

The Effect of Eyeliner on Tear Composition, Tear Secretion and Tear Film Stabili...

Zhongnan Hospital

NCT06781593 N/A

Combining Light Therapy and CPAP in Depression

Major Depression

Hôpital le Vinatier

NCT07609693 N/A

The Relationship Between Oxytocin Massage in Mothers With Insufficient Milk Prod...

Lactation Disorders

Turkey (Türkiye)

Tokat Gaziosmanpasa University

NCT05958706 N/A

Mitochondrial Substrate Utilization in the Diabetic Human Heart

Heinrich-Heine University, Due

NCT05867004 N/A

Blocking TNF to Potentiate the ICI-dependent Immune Awakening in Melanoma

Institut Claudius Regaud

NCT07039552 N/A

Development and Validation of an Ovarian Cancer Risk Prediction Model for Family...

Hereditary Breast and Ovarian Cancer Syndrome

Peking University Third Hospit

NCT06646952 N/A

CD147 Targeting Nanobody Probe for PET Imaging in Solid Tumors

NCT07411352 N/A

Left Lateral Position vs Supine Position to Reduce Active Labor Duration

Universidad Nacional Autonoma

NCT06487052 N/A

Evaluation of the Standard Catheter-directed Thrombolysis Effectiveness in Inter...

Pulmonary Embolism Acute

Federal State Budgetary Instit

NCT06603558 N/A

Post-Marketing Study to Assess the Safety and Effectiveness of Oral Atogepant in...

Chronic Migraine

NCT05570448 N/A

Anti-Reflux Endoscopic TX Using APC (AREA) in GERD Patients: (The AREA Study)

Gastro Esophageal Reflux

Midwest Veterans' Biomedical R

NCT04197648 N/A

Effects of Exercise on Thoracic Aneurysms

Thoracic Aortic Aneurysm

Laval University

NCT06956755 N/A

Registry of Myelodysplastic Syndromes and Therapy-related Acute Myeloid Leukemia

Myelodysplastic Syndromes

Groupe Francophone des Myelody

NCT06570278 N/A

Role of High-Throughput Whole Genome Sequencing for the Diagnosis and Care of At...

Diabetes Mellitus

Institut National de la Santé

NCT06782815 N/A

Acupoint Selection Based on Meridian Theory in Primary Insomnia of Liver Depress...

Primary Insomnia

NCT06906276 N/A

Brain Activity During Complex Walking in People With Atypical Parkinsonian Syndr...

Gait Disorders, Neurologic

Karolinska Institutet

NCT05536076 N/A

Effect of Hypercapnia Treatment on Respiratory Recovery After Spinal Cord Injury

VA Office of Research and Deve

NCT06849076 N/A

The Influence of Talocrural Manipulation on Proprioception in Stroke

Turkey (Türkiye)

Bitlis Eren University

NCT06876740 N/A

Project Safe Guard-Trauma

University of Colorado, Denver

NCT06299189 N/A

A Therapist Guided Internet-delivered Treatment for Adults With ADHD (Attention ...

Haukeland University Hospital

Page 6 of 276 — 6,885 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: September 2026 · Data Methodology