A Phase 1 Open-Label, Multi-Center, Safety and Efficacy Study of PRT3645 in Participants With Select Advanced or Metastatic Solid Tumors
This is a Phase 1 dose-escalation study of PRT3645, a Cyclin-dependent Kinase 4/6 (CDK4/6) inhibitor, in patients with advanced or metastatic solid tumors. The purpose of this study is to investigate the safety, tolerability, dose limiting toxicity, and to determine maximally tolerated dose and recommended phase 2 dose to be used in subsequent development of PRT3645.
• Histologically confirmed advanced, recurrent, or metastatic solid tumor malignancy that have either progress or ineligible for standard of care therapy:
‣ HR+ and HER2- or HR+ and HER2+ breast cancer
⁃ Recurrent GBM (IDH wild type) or CDKN2A/B homozygous deleted IDH-mutant astrocytoma
⁃ KRAS-mutant or SMARCA4 loss NSCLC
⁃ CDK pathway alternation in any of the following tumor types: malignant mesothelioma, HPV-negative HNSCC (including oral cavity, oropharynx, hypopharynx, and larynx), sarcoma, or NSCLC
⁃ Estrogen receptor positive with TP53 wild type endometrial cancer
• Willing and able to comply with all scheduled visits, treatment plan, laboratory tests, lifestyle considerations, and other study procedures
• Must have measurable or non-measureable (but evaluable) disease
• Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1 or Karnofsky Performance Status (KPS) ≥80% (KPS is for GBM only)
• Adequate organ function.
• Able to swallow and retain oral medication.
• Must provide either archival or fresh tumor tissue sample during screening.