Onyx Initiates Phase 1 Study For Advanced Solid Tumors

Onyx Pharmaceuticals has begun enrolling patients in a phase 1 study of ONX 0801, a novel alpha-folate receptor-mediated thymidylate synthase (TS) inhibitor, as a potential treatment for advanced solid tumors. The open-label, dose-finding study will evaluate the safety and pharmacokinetics of ONX 0801 in patients with advanced solid tumors.

The company said that open-label, dose-finding phase 1 study evaluates the safety and pharmacokinetics of ONX 0801 in approximately 60 cancer patients with advanced solid tumors. Cohorts of 3 to 6 patients will receive ONX 0801 at escalating doses until a maximum tolerated dose is determined. Each patient will receive a 3-hour intravenous infusion of ONX 0801 weekly (ie, on days 1, 8, and 15) of repeated 21-day treatment cycles.

ONX 0801 is designed to work by combining two proven approaches to improving outcomes for cancer patients. These include receptor-mediated targeting of tumor cells and inhibition of thymidylate synthase (TS), a key enzyme involved in cell growth and division.

In pre-clinical studies, ONX 0801 targeted malignant cells that overexpress the alpha-folate receptor. It was discovered at the Institute for Cancer Research in the UK and is licensed to Onyx by BTG International.

Tony Coles, president and chief executive officer of Onyx, said: “We are pleased to advance this product candidate so quickly into the clinic, following our acquisition of the compound late last year. ONX 0801 has a high selectivity for cancer cells that we believe will distinguish it from other agents in this proven class of drugs. We expect this forward momentum in building our portfolio to continue, as we strategically maximize opportunities that will drive long-term sustainable growth.”