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Recruiting Phase 3 NCT06256588

NCT06256588 A Study of Dostarlimab vs Placebo After Chemoradiation in Adult Participants With Locally Advanced Unresected Head and Neck Squamous Cell Carcinoma

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Clinical Trial Summary
NCT ID NCT06256588
Status Recruiting
Phase Phase 3
Sponsor GlaxoSmithKline
Condition Neoplasms, Head and Neck
Study Type INTERVENTIONAL
Enrollment 864 participants
Start Date 2024-03-21
Primary Completion 2028-06-30

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
DostarlimabPlacebo

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 3 trials are large pivotal studies comparing the treatment to current standard of care or placebo. Your participation directly contributes to the evidence needed for regulatory approval.

This trial targets 864 participants in total. It began in 2024-03-21 with a primary completion date of 2028-06-30.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

The goal of this study is to assess the safety and effectiveness of Dostarlimab compared to Placebo in adult participants with Head and Neck Squamous Cell Carcinoma (HNSCC)

Eligibility Criteria

Inclusion Criteria: Participants are eligible to be included in the study only if all of the following criteria apply: * Has newly diagnosed unresected Locally Advanced (LA) histologically confirmed HNSCC of the oral cavity, oropharynx, hypopharynx or larynx and completed cisplatin plus radiotherapy (termed "CRT" in this protocol) with curative intent and has no evidence of distant metastatic disease. * Has provided acceptable core or excisional biopsy obtained prior to CRT: * PD-L1 positive tumor status * If the primary tumor site is oropharyngeal carcinoma, the participant must have p16 immunohistochemistry (IHC) testing. * Has an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 * Has adequate organ function. Exclusion Criteria: Participants are excluded from the study if any of the following criteria apply: * Has received prior radiation therapy (RT), systemic therapy, targeted therapy, or surgery for management of head and neck cancer not considered part of CRT. Participants receiving induction chemotherapy are excluded. CRT combinations with components other than cisplatin and RT (e.g., experimental agents, including radiosensitizers/radioprotectants, cetuximab) are not eligible. * Has cancer outside of the oropharynx, larynx, hypopharynx or oral cavity, such as nasopharyngeal, sinus, other para-nasal, or other unknown primary head and neck cancer. Has more than one primary HNSCC tumor. * Has experienced any of the following with prior immunotherapy: any immune-related adverse event (irAE) of Grade ≥3, immune-related severe neurologic events of any grade (e.g., myasthenic syndrome/myasthenia gravis, encephalitis, Guillain-Barré Syndrome, or transverse myelitis), exfoliative dermatitis of any grade (Stevens-Johnson Syndrome, toxic epidermal necrolysis, or Drug Rash with Eosinophilia and Systemic Symptoms \[DRESS\] syndrome), or myocarditis of any grade. Non-clinically significant laboratory abnormalities are not exclusionary. * Has undergone any major surgical procedure or experienced significant traumatic injury that has not resolved by the time of randomization. * Has any history of interstitial lung disease or pneumonitis (past or current). * Has cirrhosis of any stage or current unstable liver biliary disease per investigator assessment defined by the presence of ascites, encephalopathy, coagulopathy, hypoalbuminemia, esophageal/gastric varices, or persistent jaundice. * Has a history or current evidence of any medical condition, therapy, or laboratory abnormality that might confound the study results, interfere with their participation for the full duration of the study intervention, or indicate it is not in the best interest of the participant to participate, in the opinion of the investigator. * Is receiving any other anticancer or experimental therapy. No other experimental therapies (including but not limited to chemotherapy, radiation, hormonal treatment, antibody therapy, immunotherapy, gene therapy, vaccine therapy, or other experimental drugs) of any kind are permitted while the participant is receiving study intervention. * Previous treatment with anti-PD-1, anti-PD-L1, or anti-PD-L2 agent or an agent directed to another stimulatory or coinhibitory T-cell receptor \[e.g., Cytotoxic T-lymphocyte associated protein 4 (CTLA4), OX-40, CD137\] * Is pregnant, breastfeeding, or expecting to conceive children within the projected duration of the study, starting with the Screening Visit through 120 days after the last dose of study intervention. * Has a history of severe allergic and/or anaphylactic reactions to chimeric, human or humanized antibodies, fusion proteins, or known allergies to dostarlimab or its excipients.

Contact & Investigator

Central Contact

US GSK Clinical Trials Call Center

✉ GSKClinicalSupportHD@gsk.com

📞 877-379-3718

Frequently Asked Questions

Who can join the NCT06256588 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Neoplasms, Head and Neck. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT06256588 trial and what does that mean for participants?

Phase 3 trials are large-scale studies comparing the new treatment to existing standards of care or a placebo. They provide the evidence needed for regulatory approval. This trial targets 864 participants.

Is NCT06256588 currently recruiting?

Yes, NCT06256588 is actively recruiting participants. Contact the research team at GSKClinicalSupportHD@gsk.com for enrollment information.

Where is the NCT06256588 trial being conducted?

This trial is being conducted at Jonesboro, United States, Los Angeles, United States, Solvang, United States, Stockton, United States and 11 additional locations.

Who is sponsoring the NCT06256588 clinical trial?

NCT06256588 is sponsored by GlaxoSmithKline. The trial plans to enroll 864 participants.

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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