QTc Not Prolonged by Onartuzumab Plus Paclitaxel With or Without Bevacizumab

the Cancer Therapy Advisor take:

According to a new study published in the journal Cancer Chemotherapy and Pharmacology, researchers have found that onartuzumab, when given in combination with weekly paclitaxel with or without bevacizumab, does not prolong the corrected QT (QTc) interval.

In the phase 2 study, 185 patients with locally recurrent or metastatic triple-negative breast cancer were randomly assigned to receive onartuzumab or placebo, with or without bevacizumab in combination with weekly paclitaxel as first- or second-line therapy. The aim of the study was to evaluate the effect of the regimen on patients' QTc intervals and other electrocardiogram (ECG) parameters.

Patients received a triplicate 12-lead ECG before and after each dose on day 1 of cycles 1, 2, and 4, and at the time of drug discontinuation. Onartuzumab serum samples were also collected from patients. Results showed that among the 165 patients who had ECG-evaluable data, similar changes in QTc were observed across all treatment groups.

In addition, researchers observed similar changes in PR interval, QRS duration, and heart rate across all treatment arms. No association was found between onartuzumab serum concentration and change in QTc interval. Onartuzumab is an investigational humanized anti-MET monoclonal antibody currently being studied in a variety of cancer types.