ITR-251 in Patients With Advanced Solid Tumors

This is an open-label, Phase I/Ib trial including an initial dose-escalation phase in patients with advanced solid tumors and a dose-expansion phase at recommended phase 2 dose (RP2D) in combination with Androgen Receptor Pathway Inhibitors (ARPi) in patients with metastatic castration resistant prostate cancer (mCRPC). The trial will enroll following a 3+3 design up to 6 patients with any type of solid tumors after progression to standard treatments at each dose level during the dose-escalation phase. Four dose levels are planned. If the first DL is deemed not safe, the next patients could be treated at a lower dose. If further reductions are required, the study will be stopped. After determining the RP2D, the trial will enroll up to 20 additional evaluable patients with mCRPC during the dose-expansion phase. The first six patients enrolled in the dose-expansion phase will be the safety lead in cohort for the combination and will be monitored for DLTs. The rest of patients will be enrolled afterwards at the RP2D if found safe or with a lower ITR-251 dose level if the combination shows unacceptable toxicity. The study aims to determine the RP2D of ITR-251 and the safety in combination with ARPi in mCRPC. Secondary objectives includes duration of treatment, tolerability, pharmacokinetics, and preliminary signs of antitumoral activity and efficacy. Pharmacodynamics will be an exploratory objective.