A prolonged-release tablet formulation composed of the hydrochloride salt form of the opioid receptor agonist oxycodone and the hydrochloride salt form of the opioid receptor antagonist naloxone which may produce analgesia while relieving opioid-mediated gastrointestinal (GI) side effects. Upon oral administration, oxycodone binds to opioid receptors, thereby mimicking the effects of endogenous opiates to provide analgesia. As naloxone is very poorly absorbed, this agent binds locally to opiate receptors in the GI tract, thereby preventing oxycodone from binding to these receptors. This relieves the opioid-related side effects on the GI tract, including opioid-induced constipation. Check foractive clinical trials using this agent.