Benitec Biopharma Ltd. has terminated a phase 2 study of its head and neck cancer therapy BB-401 after patients in the trial did not experience a reduction in their disease as expected.

The Australian company said in a Dec. 21 release that initial data from the first group of 12 patients in the study did not support continued enrollment. BB-401, which is a gene-silencing agent, was being studied for treating patients with squamous cell carcinoma of the head and neck that has spread to other parts of the body or has recurred.

Benetec said its scientific and clinical teams will continue to evaluate the data for the patients that have already received the medicine and will issue further results once that follow up has concluded.

The biotechnology company develops treatments for chronic and life-threatening human diseases based on its gene-silencing therapy, DNA-directed RNA interference.