Calando Pharmaceuticals, a majority-owned subsidiary of Arrowhead Research Corporation announced completion of the IT-101 Phase I clinical study conducted at City of Hope in Duarte, California. The company expects the entire study data to be published in early 2009.


IT-101 is an experimental, nanoparticle therapeutic that consists of the drug camptothecin (CPT) conjugated to a cyclodextrin polymer. IT-101, the first drug candidate in Calando’s proprietary CyclosertTM pipeline, has now successfully completed a Phase I trial designed to evaluate its safety, tolerability, and pharmacokinetics in patients with inoperable or metastatic tumors.

Initially, the trial utilized a weekly dosing schedule. However, because of the excellent pharmacokinetic characteristics observed for the drug, including a half-life of approximately 40 hours, a subsequent Phase Ib was conducted utilizing a twice monthly dosing schedule. The Phase Ia and Phase Ib studies are now completed, and all trial endpoints have been successfully achieved. The drug was found to be well tolerated in both the Phase Ia and Ib studies of the trial.

A high proportion of patients displayed stable disease following treatment thereby showing evidence of IT-101’s cytostatic activity. This activity is consistent with several published clinical studies reporting improved outcomes when lower doses of topotecan were administered on a continuous regimen compared to traditional intermittent schedules. Topotecan is an FDA-approved a cytotoxic chemotherapeutic that is an analog of CPT.

Based on these Phase I results, Calando has initiated a multi-center Phase II clinical trial in ovarian carcinoma patients. The Phase II trial is designed to determine whether IT-101 treatment can delay disease progression in stable disease patients who have completed a standard second line course of platinum chemotherapy. The concept of providing minimally toxic cytostatic therapy following traditional cytoreductive therapy to extend progression free survival, has become a promising avenue of treatment in clinical oncology. Several cancer therapeutics are approved for cancer maintenance therapy. These drugs are increasingly being implemented by oncologists as a relatively new option for patient care, with annual revenues in excess of $ 5 billion a year.

Successful completion of the IT-101 Phase I study opens numerous avenues for its further clinical investigation. In addition to the Phase II trial in ovarian cancer, other clinical trials, including testing IT-101 in lymphoma patients, are planned.