Pfizer has announced top-line results from a late-stage study which show that a new painkiller designed to prevent its misuse, ALO-02, is as safe as other opioids.
The Phase III trial of ALO-02 (extended-release oxycodone/naltrexone) in patients with moderate-to-severe chronic, non-cancer pain showed that the adverse event profile was as expected based on similar long-term safety studies with other extended-release opioid formulations. The most common were nausea, constipation, vomiting and headache, Pfizer noted, adding that the study supports the safety profile of the analgesic.
A total of 237 (60%) patients discontinued over the one-year study period, with 19% of patients reporting adverse events as the primary reason. However, Pfizer argues that the discontinuation rate was "within the expected range based on similar long-term safety studies with other extended-release opioid formulations".
ALO-02 uses technology which the company says should discourage common methods of tampering associated with prescription opioid misuse and abuse. It consists of extended-release oxycodone pellets that surround a sequestered core of naltrexone. When the pellets are crushed, the naltrexone is released and is designed to counteract the effects of oxycodone.
In June 2011, Pfizer and partner Acura Pharmaceuticals got the green light for Oxecta (immediate-release oxycodone) but a week later, the US Food and Drug Administration issued a complete response letter for Remoxy (extended-release oxycodone), co-developed with Pain Therapeutics and Durect Corp.