Clinical Trials / Browse by Phase / Phase 4

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Phase 4 Clinical Trials

Phase 4 trials (post-market surveillance) occur after a drug has been approved. They monitor long-term effectiveness and safety in general patient populations.

Total Trials

350

Recruiting Now

350

Top Conditions in Phase 4

Obesity (8) Dexmedetomidine (5) Opioid Use (5) Atrial Fibrillation (5) Postoperative Pain (5) Diabetes Mellitus, Type 2 (4) Coronary Artery Disease (4) Ischemic Stroke (4) Anesthesia (4) Depression (4)

Frequently Asked Questions — Phase 4 Trials

What is the purpose of a Phase 4 post-market clinical trial?

Phase 4 trials occur after a drug has received regulatory approval. They monitor long-term effectiveness and safety in real-world patient populations, detect rare adverse events too infrequent to appear in earlier trials, study effectiveness in subgroups (elderly, pediatric, renally impaired), and may explore new indications for the approved drug. Some Phase 4 studies are mandated by the FDA as a condition of approval.

Who sponsors Phase 4 trials?

Phase 4 trials are primarily sponsored by pharmaceutical and biotech companies that hold the drug's marketing authorization. Some are mandated by the FDA or EMA—particularly when approval was based on surrogate endpoints and confirmatory long-term data is required. Independent academic institutions and registry-based programs also conduct Phase 4 studies.

Are Phase 4 trials safer than Phase 1–3 trials?

Phase 4 trials involve drugs that have already demonstrated an acceptable safety profile in earlier phases and received regulatory approval. As a result, the risk profile for participants is generally better characterized than in early-phase trials. However, these studies are still clinical research designed partly to detect long-term or rare adverse events not observed in pre-approval trials.

Active Phase 4 Studies

NCT03416413 Phase 4

Study of Foam Sclerotherapy Versus Ambulatory Phlebectomy

Imperial College London

NCT05537935 Phase 4

Low Dose Naltrexone for Pain in Patients With HIV

Human Immunodeficiency Virus

Emory University

NCT03889743 Phase 4

Innovative Steroid Treatment to Reduce Asthma Development in Children After Firs...

Finland, Norway, Sweden

St. Olavs Hospital

NCT07308015 Phase 4

Clinical Study on the Treatment of Rhinitis Sicca With Sodium Hyaluronate Adjust...

China-Japan Union Hospital

NCT07199335 Phase 4

Long-acting Cabotegravir Injectable Pre-exposure Prophylaxis for People Who Inje...

Massachusetts General Hospital

NCT06613425 Phase 4

Clinical Study of Combined Platelet Transfusion

Hematologic Diseases

The General Hospital of Wester

NCT03684018 Phase 4

Two Dose Levels of Privigen in Pediatric CIDP

Pediatric Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

NCT07031128 Phase 4

Alpha Ketoglutarate Enhances Geroprotection In Surgery (AEGIS)

National University Hospital,

NCT04730609 Phase 4

Dexmedetomidine for Intraoperative Shivering in Scheduled Elective Cesarean Deli...

NCT06529406 Phase 4

Prospective Evaluation of Sequencing From antiCD-20 Therapies to Ozanimod

Relapsing Multiple Sclerosis

University of Colorado, Denver

NCT07303738 Phase 4

The Use of High Bile-binding Foods to Reduce Upper Gastrointestinal Bile Acid Co...

Feeding Difficulties

Boston Children's Hospital

NCT06674226 Phase 4

Effects of Ciprofol on Postoperative Delirium and Outcomes in Elderly Patients U...

Postoperative Delirium (POD)

NCT07474519 Phase 4

Studying the Relationship of Patient Positioning and Intravesical Bacillus Calme...

Non-Muscle Invasive Bladder Carcinoma

Ohio State University Comprehe

NCT07322419 Phase 4

Hemodynamics During Cesarean Delivery Under Spinal Anesthesia With Norepinephrin...

Cesarean Delivery

Mansoura University

NCT05626530 Phase 4

Letermovir for Secondary Prophylaxis in Solid Organ Transplant Recipients

Cytomegalovirus Infections

Tufts Medical Center

NCT07154719 Phase 4

GLP-1R Actions on Muscle and the Skeleton

Musculoskeletal Abnormalities

Pennington Biomedical Research

NCT05856136 Phase 4

A Study to Investigate of the Effects of Opioid Exposure on the Ability of the D...

Respiratory Function Loss

NCT07149792 Phase 4

A Multi-center RCT Clinical Trial on Personalized Precision Medicine for Patient...

Taichung Veterans General Hosp

NCT05745987 Phase 4

Smallpox Vaccine for Mpox Post-Exposure Prophylaxis: A Cluster RCT

Democratic Republic of the Congo, Nigeria, Uganda

McMaster University

NCT07221019 Phase 4

Single Shot Exparel vs Catheters in Lower Extremity Trauma

Fracture Dislocation of Ankle Joint

George Washington University

NCT05702944 Phase 4

The Effect and Safety of Omitting Preoperative Alpha-adrenergic Blockade for Nor...

Pheochromocytoma

Seoul National University Hosp

NCT05929729 Phase 4

Iron Deficiency Anemia (IDA) and the Brain

IDA - Iron Deficiency Anemia

Children's Hospital Los Angele

NCT05682131 Phase 4

South China Children Cancer Group - Relapsed-Acute Lymphoblastic Leukemia 2022 P...

Arsenic Trioxide

Sun Yat-Sen Memorial Hospital

NCT03759028 Phase 4

Supracondylar Post-Operative Pain Study

Supracondylar Humerus Fracture

University of California, Los

NCT06639828 Phase 4

Phase 4 Paediatric Study to Evaluate Sonazoid Safety and Efficacy for Contrast-E...

Focal Liver Lesions

Germany, Italy, United Kingdom

Page 5 of 14 — 350 trials total

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