Intravenously Administered Liposomal PROMITIL in Combination With External Beam Radiotherapy in Cancer Patients

Overview

This will be a multi-center, open-label, single-arm, prospective study, in which up to 18 adult patients requiring radiotherapy for metastatic disease or for an inoperable primary tumor with no definitive curative treatment option, will undergo a combination treatment of intravenously (IV) delivered PROMITIL and standard of care radiotherapy. The treatment regimen will involve administration of two PROMITIL doses, delivered at a 21-day interval, and a course of EBR (type of RT according to investigator's preference), initiated 1-3 days after the first PROMITIL dose and completed within a 2-week period. EBR will consist of no more than 10 fractions delivered within 2 weeks as conventionally fractionated RT, or SBRT. Treatment safety will be assessed on a weekly basis throughout the two 21-day treatment courses (42 days) and throughout the follow-up period (up to Day 127). AEs will only be logged until 6 weeks after the last PROMITIL dose (up until Day 64). Disease status will be reevaluated between days 43-50 of the study, and every 6 weeks thereafter (Days 85 and 127±7 days). In addition, following completion of the treatment schedule, all patients will be followed up by phone every 12 weeks, until either death, disease progression (PD), withdrawn consent or trial cut-off date, i.e., for up to 2 years after patient accrual to study, (whichever occurs first). The following anticancer agents will NOT be allowed during the screening period, 6-week treatment period and until first disease reevaluation: cytotoxic agents, non-cytotoxic myelosuppressive agents (CDK 4/6 inibitiors, PARP inhibitors, m-TORS inhibitors and tyrosine kinase-inhibitors). Treatment with hormonal agents, monoclonal antibodies (anti-EGFr, anti-Her2, anti-VEGF and VEGFr, anti-PD1, anti-PDL1) and bisphosphonates can be continued during the study.

As combination with radiotherapy is expected to provide an additive or synergistic effect, the current dose-escalation study will begin with a dose of 1.25 mg/kg, to be followed by an increase (1.5 mg/kg) in Cohort 2 and a further increase 1.8 mg/kg in Cohort 3 in the absence of DLTs after two treatment cycles, with an interluding 10-fraction course of radiotherapy. PROMITIL will be intravenously delivered on Day 1 of each of the two 21-day cycles. Cohort 1: The first 6 patients recruited to the study will receive 1.25 mg/kg PROMITIL. Cohort 2: If no dose-limiting toxicities (DLTs) are recorded by day 43 of the study, the second cohort of 6 patients will begin treatment at a dose level of 1.5 mg/kg PROMITIL. However, if 1 DLT is recorded, the second cohort of 6 patients will receive the same dose of 1.25 mg/kg PROMITIL. If 2 DLTs are recorded in Cohort 1, the second cohort of 6 patients will receive 1.0 mg/kg PROMITIL. Cohort 3: If no dose-limiting toxicities (DLTs) are recorded by day 43 of the study of the first 3 patients of Cohort 2, a third cohort will enroll 6 patients to receive treatment at a dose level of 1.8 mg/kg PROMITIL. If none or 1 DLT is recorded, the dose of 1.8 mg/kg will be cleared as recommended dose for phase 2. If 2 DLT are recorded, the study will be terminated as soon as the 2nd DLT is recorded, and the prior dose level of 1.5 mg/kg will be cleared as recommended dose for phase 2