Study of OB-002 in Patients With Refractory Metastatic Cancer

The dose escalation will use a conventional 3+3 approach, at a minimum of four planned dose levels (0.25, 0.5, 1.0, and 1.5 mg/kg), to establish a maximum tolerated dose (MTD). Additional dose levels may be investigated if PK, pharmacodynamic (PD), safety, and efficacy data indicate higher dose levels may be appropriate. The first patient - sentinel patient - at each dose level will be observed for three days before additional patients can be dosed within the same dose level. The patients will be dosed once weekly (Days 1, 8, 15, and 22) over a 4-week treatment cycle with a 28-day dose-limiting toxicity (DLT) observation period. After a full cohort has completed Day 28 assessments there will be a pause for safety evaluation conducted by the Safety Monitoring Committee (SMC). Once safety data have been reviewed, the SMC will make their recommendations to Orion who will decide whether to proceed to dosing the next dose cohort. Screening may continue during the SMC pause. Once all patients in the highest planned cohort (1.5 mg/kg OB 002) have completed Day 28 assessments, safety, PK, receptor occupancy (RO), and tolerability data will be reviewed to determine which dose level should be expanded or whether an additional dose level is needed. The expanded cohort will enrol 6 patients at the identified dose level. Patients may remain on treatment until disease progression with a follow-up (FU) period of up to 12 months. All adverse events (AEs) and non-invasive tumor assessments will be documented throughout the FU period to characterize the objective response rate (ORR) and, progression-free survival (PFS). Patients that do not complete the DLT observation period for non-DLT reasons will be replaced