BioCentury
ARTICLE | Clinical News

Otlertuzumab: Interim Phase Ib data

January 6, 2014 8:00 AM UTC

Interim data from 20 evaluable previously untreated CLL patients in the first cohort of the open-label, U.S. Phase Ib Study 16009 showed that a single 10 mg/kg dose of IV otlertuzumab followed by once-weekly doses of 20 mg/kg IV otlertuzumab for 8 weeks followed by once-monthly doses of 20 mg/kg IV otlertuzumab for 4 months plus rituximab led to an ORR of 50% according to 2008 International Workshop on CLL (IWCLL) response criteria. The complete response (CR) rate was 5% and the partial response (PR) rate was 45%. According to 1996 National Cancer Institute (NCI) Working Group response criteria, the ORR was 96% in 23 evaluable patients, including a CR rate of 33% and a PR rate of 63%. Otlertuzumab was well tolerated. Infusion reactions occurred in 54% of patients. Serious adverse events were reported in 4 patients and included pneumonia, systemic inflammatory response, deep vein thrombosis (DVT), lymph node pain, worsening sinusitis and fever. Data were presented at the American Society of Hematology meeting in New Orleans.

Last April, Emergent amended the trial to include 2 additional cohorts of 16 patients each to evaluate the combination in relapsed CLL patients and to evaluate a lower dose of otlertuzumab plus rituximab in previously untreated CLL patients. Patients in the cohorts are receiving 6 m/kg otlertuzumab for the first dose and 10 (previously untreated) or 20 (relapsed) mg/kg thereafter. Emergent said the additional cohorts were included to test whether the lower dose will be as efficacious as the higher dose and was not due to any safety issues (see BioCentury, April 15, 2013). Otlertuzumab has Orphan Drug designation in the U.S. and EU for CLL. ...