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EF-41/KEYNOTE D58: Phase 3 Study of Optune Concomitant With Temozolomide Plus Pembrolizumab in Newly Diagnosed Glioblastoma
NCT06556563 · View on ClinicalTrials.gov ↗
Study Summary
This is a multicenter, two-arm, randomized, double-blind, placebo-controlled study of Optune® (Tumor Treating Fields at 200 kHz) together with maintenance Temozolomide (TMZ) chemotherapy agent and pembrolizumab compared to Optune® together with maintenance TMZ and placebo in newly diagnosed Glioblastoma (GBM) patients. The primary objective of the study is to evaluate the Overall Survival (OS).
Conditions Studied
Interventions
- DRUG Pembrolizumab
- DRUG Placebo
- DRUG Temozolomide
- DEVICE Optune® device
Study Locations (20)
Florida
- UF Health Neuromedicine — Gainesville
- Mayo Clinic - Florida — Jacksonville
- Miami Cancer Institute — Miami
- Moffitt Cancer Center — Tampa
California
- University of Southern California — Los Angeles
- Hoag Memorial Hospital Presbyterian — Newport Beach
- Stanford Cancer Institute — Palo Alto
New York
- Northwell Health — Lake Success
- Columbia University Irving Medical Center — New York
- Montefiore Medical Center- Montefiore Medical Park — The Bronx
Minnesota
- Masonic Cancer Center, University of Minnesota — Minneapolis
- Mayo Clinic - Rochester — Rochester
Arizona
- Mayo Clinic Hospital — Phoenix
Illinois
- Northwestern Memorial Hospital — Chicago
Kentucky
- University of Kentucky Medical Center — Lexington
Maryland
- University of Maryland — Baltimore
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 741 participants |
| Start Date | 2025-02-03 |
| Est. Completion | 2029-04 |
| Phase | Phase 3 |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT06556563
The ClinicalTrials.gov registry entry for NCT06556563 describes a study currently listed as recruiting. It is categorized as Phase 3, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 741 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is NovoCure, which has 32 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 1 condition, with Glioblastoma appearing as the primary indexed condition, and to 4 interventions — of which Pembrolizumab is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT06556563 reports 20 study locations spanning 12 distinct geographic areas — top geographies include Florida, California, New York. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT06556563 about?
NCT06556563 is a clinical study titled "EF-41/KEYNOTE D58: Phase 3 Study of Optune Concomitant With Temozolomide Plus Pembrolizumab in Newly Diagnosed Glioblastoma". This is a multicenter, two-arm, randomized, double-blind, placebo-controlled study of Optune® (Tumor Treating Fields at 200 kHz) together with maintenance Temozolomide (TMZ) chemotherapy agent and pembrolizumab compared to Optune® together with maintenance TMZ and placebo in newly diagnosed Glioblas...
What is the current status of trial NCT06556563?
This trial is currently recruiting. It is a Phase 3 study. The enrollment target is 741 participants. The study started on 2025-02-03. Estimated completion is 2029-04.
What conditions does trial NCT06556563 study?
This clinical trial studies the following conditions: Glioblastoma. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT06556563?
The interventions under investigation include: Pembrolizumab (DRUG), Placebo (DRUG), Temozolomide (DRUG), Optune® device (DEVICE). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT06556563?
This trial is sponsored by NovoCure, which has 32 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT06556563 being conducted?
This trial has 20 study locations across Arizona, California, Florida, Illinois, Kentucky. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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