Clinical trial · Interventional
A Study of PRT3645 in Participants With Select Advanced or Metastatic Solid Tumors
A Phase 1 Open-Label, Multi-Center, Safety and Efficacy Study of PRT3645 in Participants With Select Advanced or Metastatic Solid Tumors
NCT05538572CI-TRIAL-00078437completedPhase 1ClinicalTrials.gov clinicaltrialsProvenance
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
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.
Conditions
Conditions (7)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Breast Cancer | Malignant Breast Neoplasm | CURATED_EXACT | 0.92 |
| Endometrial Cancer | Malignant Endometrial Neoplasm | CURATED_BROADER | 0.80 |
| Glioblastoma | Glioblastoma | CURATED_BROADER | 0.80 |
| Head and Neck Squamous Cell Carcinoma | Head and Neck Squamous Cell Carcinoma | ONTOLOGY_EXACT | 0.98 |
| Malignant Mesothelioma | Malignant Mesothelioma | ONTOLOGY_EXACT | 0.98 |
| Non-small Cell Lung Cancers | Lung Non-Small Cell Carcinoma | ALIAS | 0.90 |
| Sarcoma | Sarcoma | ONTOLOGY_EXACT | 0.98 |
Interventions
Interventions (1)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| PRT3645 | Drug | — | UNRESOLVED |
Design
Arms and outcomes
Arms (1)
- type
- EXPERIMENTAL
- label
- PRT3645
- description
- PRT3645 capsules will be self-administered once daily, continuously, at the dose-level assigned
- interventionNames
- Drug: PRT3645
Primary outcomes (3)
- measure
- Dose limiting toxicity (DLT) of PRT3645
- timeFrame
- Baseline through Day 28
- description
- Dose limiting toxicity will be evaluated over the 28-day observation period
- measure
- Safety and tolerability of PRT3645: AEs, CTCAE Assessments
- timeFrame
- Baseline through approximately 2 years
- description
- Safety and tolerability will be evaluated by incidence of DLTs, laboratory measurements, severity of adverse events (AEs) according to National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) v5.0.
Eligibility
Eligibility (as posted)
- Sex
- All
- Minimum age
- 18 Years
Show eligibility criteria text
Inclusion Criteria: * Histologically confirmed advanced, recurrent, or metastatic solid tumor malignancy that have either progress or ineligible for standard of care therapy: 1. HR+ and HER2- or HR+ and HER2+ breast cancer 2. Recurrent GBM (IDH wild type) or CDKN2A/B homozygous deleted IDH-mutant astrocytoma 3. KRAS-mutant or SMARCA4 loss NSCLC 4. 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 5. 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. Exclusion Criteria: * Participants with advanced, symptomatic, extensive visceral disease. * Active inflammatory bowel disease or chronic diarrhea, short bowel syndrome, any upper gastrointestinal surgery including gastric resection, known malabsorption syndrome, or other condition that may impair absorption of PRT3645. * Treatment with strong inhibitors of CYP3A4. * History of another malignancy within 3 years except for adequately treated basal cell or squamous cell skin cancer, superficial bladder cancer, prostate intraepithelial neoplasm, carcinoma in situ of the cervix, or other noninvasive or indolent malignancies, or malignancies previously treated with curative intent and not on active therapy or expected to require treatment or recurrence during the study. * Clinically significant or uncontrolled cardiac disease, uncontrolled electrolyte disorders, uncontrolled or symptomatic CNS metastases or leptomeningeal disease except for GBM. * Endometrial cancer patients who had received prior treatment with a CDK 4/6 inhibitor.
References
Publications (0)
Data not yet available
No reference posted for this study.