September 11, 2008 Calando Pharmaceuticals Inc., a majority owned subsidiary of Arrowhead Research Corp., has initiated a Phase II clinical trial in the US evaluating the safety and efficacy of its drug candidate, IT-101, in patients with platinum-sensitive ovarian cancer. The study is open for enrollment, with expectations of 150 patients in the US.

IT-101, a conjugate of camptothecin and the cyclodextrin polymer nanoparticle, Cyclosert, has demonstrated a highly favorable toxicity profile and pharmacokinetic characteristics.

Previous work with IT-101 suggests that twice monthly “maintenance doses” of IT-101 given after the patient’s standard chemotherapy may have minimal side effects, allowing for improved quality of life, and improved progression free survival. This Phase 2 study is designed to determine if IT-101 treatment initiated after a standard 2nd line course of platinum chemotherapy in patients who have stable disease, a partial response, or a complete response can delay disease progression.

The study is co-led by two doctors: Jonathan Berek, prof. and chair, department of obstetrics and gynecology, Stanford University School of Medicine and the Stanford Cancer Center; and Franco Muggia, professor of oncology, director of the division of medical oncology at NYU Medical Center and associate director for clinical research. A team of experts from Dana Farber, Sloan Kettering, Columbia U., and M.D. Anderson comprise the data safety monitoring committee.

Efficacy of IT-101 (bottom panel) in a disseminated TC71-luc (Ewing’s Sarcoma) tumor model in NOD/SCID mice. Numbers across top of panels indicate days before, or following, initial treatment; complete remission was achieved with IT-101 treatment. Tumor burden was monitored using a Xenogen imaging system. Mice were treated on days 0, 7 and 14, dosed with irinotecan IP at 100mg/kg and IT-101 IV (tail vein injection) at 12.5mg/kg.