PRIMARY OBJECTIVE:~I. To determine the recommended phase 2 dose (RP2D) of M3814 (peposertib) when given in combination with intensity-modulated radiation therapy (IMRT).~SECONDARY OBJECTIVES:~I. To evaluate the safety and tolerability of the combination of M3814 (peposertib) with radiotherapy.~II. To estimate the rates of grade 3 or greater acute toxicities of the regimen.~III. To estimate late toxicities of the regimen. IV. To evaluate the clinical response rate, based on Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, at 3 months post completion of radiotherapy.~V. To estimate 6 and 12-month progression-free survival (PFS) in the dose expansion cohort (DEC).~VI. To estimate 6 and 12-month overall survival (OS) in the DEC.~EXPLORATORY OBJECTIVE:~I. To estimate the pharmacokinetic (PK) parameter of M3814 (peposertib) using population PK approaches.~OUTLINE: This is a dose-escalation study of peposertib.~Beginning 60-90 minutes before each radiation treatment, patients receive peposertib orally (PO) once daily (QD) and undergo IMRT daily Monday-Friday for 7 weeks in the absence of disease progression or unacceptable toxicity.~After completion of treatment, patients are followed up every 3 months for 2 years.
This phase I trial investigates the side effects and best dose of peposertib when given together with radiation therapy in treating patients with head and neck cancer that has spread to other places in the body (advanced) who cannot take cisplatin. Peposertib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Radiation therapy uses high energy x-rays to kill tumor cells and shrink tumors. This trial aims to see whether adding peposertib to radiation therapy is safe and works well in treating patients with head and neck cancer.