Alnylam Pharmaceuticals this week released new phase I data on its investigational liver cancer drug ALN-VSP, which showed the drug to be "generally well tolerated."
According to the company, the maximum tolerated dose of ALN-VSP has not yet been reached and enrollment in the trial is continuing in a dose-escalating manner.
So far, 127 doses of ALN-VSP ranging from 0.1 to 1.25 mg/kg have been administered to 28 patients, with two to 13 doses administered per patient, the company said. "The majority of these patients have colorectal cancer, a primary tumor that often metastasizes to the liver."
"Several patients enrolled in the higher dose groups have achieved stable disease," Alnylam added. "Patients who achieved stable disease have been enrolled in a dose extension study … designed to enroll patients that have completed four months of dosing cycles and achieved designation of at least stable disease."
The company previously disclosed that a patient with advanced pancreatic neuroendocrine cancer with extensive involvement of the liver developed hepatic failure five days following the second dose at 0.7 mg/kg and later died. "This was deemed possibly related to the study drug," Alnylam said.
"At 1.25 mg/kg, a patient experienced grade three thrombocytopenia after the first dose," which was deemed related to the study drug but resolved within five days, it noted. "There have been three acute infusion reactions at 0.4, 0.7, and 1.25 mg/kg, [and] all three patients tolerated further treatment with prolongation of infusion duration. None of these events preclude further dose-escalation."
Alnylam said it is continuing to enroll patients to determine the maximum tolerated dose of ALN-VSP, and that it is further assessing safety and activity in this dose in the expansion phase of the study.
"We have also obtained a significant number of human biopsy samples in this study with which we intend to perform molecular analyses for RNAi delivery and pharmacology. We expect to further update these results" in 2011, the firm said.