PF614 Analgesic Activity in Acute Postoperative Pain (PF614-301)

The goal of this clinical trial is to evaluate the analgesic activity of PF614 (an oral oxycodone prodrug extended-release analgesic) for control of postsurgical pain in subjects scheduled for abdominoplasty surgery. The main question to be answered is: • To assess the analgesic efficacy of PF614 compared to placebo in subjects with moderate to severe pain following abdominoplasty. Participants will be asked to take oral blinded doses of study medication at about one hour before surgery starts, and then every 12 hours after surgery for up to 4 days. Participants will be asked to: * Rate their pain on a 0-10 numerical rating scale (NRS) at various timepoints up to 5 days following surgery; * Tell us about the need for rescue medication if they continue to have moderate-to-severe pain; * Tell us about any side effects or adverse effects that they may experience to help us understand the safety and tolerability of the test medications; * Provide periodic blood samples to help us understand how much study drug is in their system. Participants will stay in a clinic setting and be monitored for safety for 5 days following surgery. We anticipate that participants will be discharged on Day 5, pending medical review, and then keep a diary to record study-related pain and adverse effects for an additional 2-4 days after discharge.