Pacira Pharmaceuticals, Inc. (NASDAQ: PCRX) today announced initiation of its Phase 2/3 pivotal trial of EXPAREL ® (bupivacaine liposome injectable suspension) administered as a single-dose injection femoral nerve block for total knee arthroplasty surgery. Results from this study and a forthcoming second trial focused on intercostal nerve block for thoracotomy will contribute to a planned U.S. Food and Drug Administration supplemental New Drug Application (sNDA) filing in late 2013 or early 2014.
The first of approximately 280 patients undergoing total knee arthroplasty (TKA) has been enrolled in the study. Designed as a two-part study, the first part will evaluate the safety and efficacy of three doses of EXPAREL to identify a single therapeutic dose for further investigation. In the second part of the study, patients will receive either the selected dose of EXPAREL or placebo as a femoral nerve block.
In addition to pharmacokinetic and safety data, multiple efficacy endpoints will be measured, including:
- Primary endpoint: Cumulative pain scores (pain intensity over time) through 72 hours
- Other endpoints:
- Total postsurgical opioid consumption through 72 hours
- Time to first opioid rescue
- Patient satisfaction with postsurgical analgesia at 72 hours and 30 days
- Proportion of patients who are pain free
The term nerve block pertains to the placement of a local anesthetic in close proximity to a nerve in order to create local analgesia. Bupivacaine, whose analgesic effect typically lasts for up to eight hours, is the current standard of care in many nerve block procedures.“Patients undergoing orthopedic procedures, such as a total knee arthroplasty, traditionally experience several days of postsurgical pain. Currently, to obtain analgesia that spans multiple days, anesthesiologists can implement a continuous nerve block by inserting a catheter into the body that is hooked to an external drug reservoir and pump in order to bathe the nerve in local anesthetic,” said Gary Patou, MD, chief medical officer at Pacira. “Just as we have seen with elastomeric pumps addressing postsurgical pain through local infiltration, these devices can be prone to migration, infection and leakage, all of which can significantly impact postsurgical analgesia and patient recovery. A femoral nerve block that can potentially provide several days of analgesia with a single-dose injection of EXPAREL could eliminate the need for external catheters and devices and significantly contribute to the management of postsurgical pain.”