Pacira Pharmaceuticals, Inc. (NASDAQ:PCRX) today announced that its Phase 4 study of EXPAREL® (bupivacaine liposome injectable suspension) in patients undergoing Cesarean section (C-section) achieved its primary endpoint with a statistically significant reduction in total postsurgical opioid consumption through 72 hours (P≤0.05). EXPAREL also achieved statistical significance for reduction in pain intensity scores through 72 hours (P≤0.05). The full study results will be submitted for publication in the peer-reviewed medical literature later this year.
“Research shows that inadequately managed postsurgical pain can interfere with a new mother’s ability to care for herself and her infant, and that those mothers experiencing severe pain following cesarean delivery are at increased risk for persistent pain, persistent opioid use, and postpartum depression,” said Ashraf Habib, MD, Chief, Division of Women’s Anesthesia and Professor of Anesthesiology at Duke University and investigator in the study. “TAP blocks have become an increasingly integral part of anesthesiologists’ armamentarium of opioid-sparing pain management approaches, and this study demonstrates that, when added to the standard of care, an EXPAREL TAP block provides a superior long-acting field block that not only adequately controlled patients’ pain following C-section, but also greatly reduced their need for opioids.”
This was a multicenter, randomized, double-blind study including a total of 13 sites and 186 patients. Patients undergoing elective C-section and given spinal anesthesia were randomized to receive EXPAREL or the active comparator bupivacaine HCl. Patients in the EXPAREL arm were administered a transversus abdominis plane (TAP) field block with 10 mL EXPAREL admixed with 10 mL 0.25% bupivacaine HCl and 10 mL normal sterile saline injected bilaterally (for a total volume of 60 mL). Patients in the active comparator arm received a TAP field block with 10 mL 0.25% bupivacaine HCl admixed with 20 mL normal sterile saline injected bilaterally (for a total volume of 60 mL).
In accordance with current medical practice, prior to C-section all patients in this study received an intrathecal injection of 150 mcg preservative-free morphine for spinal injection in conjunction with single-shot spinal anesthesia using 1.4-1.6 mL bupivacaine HCl 0.75% and 15 mcg fentanyl. Following C-section, patients also received 15 mg of intravenous (IV) ketorolac, 1000 mg of IV acetaminophen at the time of skin incision closure, and oral acetaminophen and ibuprofen beginning 6 hours after skin incision closure for up to 72 hours following surgery. Rescue medication was available upon request and postsurgical opioid consumption through 72 hours was collected. Pain intensity was measured using visual analog scale (VAS) pain intensity scores at rest from 6 to 72 hours.
As a follow-on to this study, Pacira will soon begin enrollment in CHOICE, its next-generation C-section trial designed to be completely opioid-free in the EXPAREL arm, including opioid-free spinal anesthesia.
“Effective postsurgical pain control is a critical element in patient recovery following surgery, especially for new mothers who often experience significant pain in the first few days following C-section,” said Richard Scranton, MD, chief medical officer of Pacira. “This study provides clinical evidence that an EXPAREL-based multimodal regimen significantly reduces the need for opioids versus current multimodal approaches that combine bupivacaine, acetaminophen and an NSAID. We look forward to continuing to advance our opioid-free CHOICE study, which we believe will help transform the standard of pain management for Cesarean section patients.”