NCT03712605

Testing Pembrolizumab Versus Observation in Patients With Merkel Cell Carcinoma After Surgery, STAMP Trial

STAMP: Surgically Treated Adjuvant Merkel Cell Carcinoma With Pembrolizumab, a Phase III Trial

• Status: Active Not Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 280 (estimated)
• Sponsor: National Cancer Institute (NCI) · NIH
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This phase III trial studies how well pembrolizumab works compared to standard of care observation in treating patients with stage I-III Merkel cell cancer that has been completely removed by surgery (resected). Immunotherapy with monoclonal antibodies, such as pembrolizumab, may help the body's immune system attack the cancer, and may interfere with the ability of tumor cells to grow and spread.

Detailed description

PRIMARY OBJECTIVE: I. To compare recurrence free survival (RFS) and overall survival (OS) as co-primary endpoints across the two arms. SECONDARY OBJECTIVES: I. To evaluate adverse events. II. To evaluate distant metastasis free survival (DMFS). III. To evaluate the impact of radiation on clinical outcomes (OS, RFS, DMFS). OUTLINE: Patients are randomized to 1 of 2 arms. ARM A: Patients receive pembrolizumab intravenously (IV) over 30 minutes on day 1 of each cycle. Treatment repeats every 21 days for up to 17 cycles in the absence of disease progression or unacceptable toxicity. Patients may also undergo standard of care radiation therapy within 14 days of day 1, cycle 1. Patients undergo positron emission tomography (PET)-computed tomography (CT), CT, or magnetic resonance imaging (MRI) throughout the trial. Patients may also undergo blood and utine sample collection as clinically indicated at the discretion of the treating investigator. ARM B: Patients receive standard of care observation every 3 months for 1 year, and then every 6 months for 5 years. Patients may also undergo standard of care radiation therapy within 14 days of day 1, cycle 1. Patients undergo PET-CT, CT, or MRI throughout the trial. Patients may also undergo blood and urine sample collection as clinically indicated at the discretion of the treating investigator. After completion of study treatment, patients are followed up every 3-6 months for 5 years from the date of registration.

Conditions

• Pathologic Stage I Cutaneous Merkel Cell Carcinoma AJCC v8
• Pathologic Stage II Cutaneous Merkel Cell Carcinoma AJCC v8
• Pathologic Stage III Cutaneous Merkel Cell Carcinoma AJCC v8

Interventions

Type	Name	Description
OTHER	Best Practice	Receive standard of care observation
PROCEDURE	Biospecimen Collection	Undergo blood and urine sample collection
PROCEDURE	Computed Tomography	Undergo PET-CT or CT
PROCEDURE	Magnetic Resonance Imaging	Undergo MRI
BIOLOGICAL	Pembrolizumab	Given IV
PROCEDURE	Positron Emission Tomography	Undergo PET-CT
RADIATION	Radiation Therapy	Undergo radiation therapy

Timeline

• Start date: 2018-11-15
• Primary completion: 2026-12-31
• Completion: 2026-12-31
• First posted: 2018-10-19
• Last updated: 2026-04-13

Locations

554 sites across 1 country: United States

Regulatory

• FDA-regulated drug study