A randomized, multicenter, pilot study comparing the efficacy and safety of a bupivacaine-collagen implant (XaraColl®) with the ON-Q PainBuster® Post-op Pain Relief System following open gynecological surgery

BACKGROUND XaraColl(®), a collagen-based intraoperative implant that delivers bupivacaine to the site of surgical trauma, is under development for postoperative analgesia. We compared the efficacy and safety of XaraColl for the prevention of postsurgical pain versus a slow postoperative perfusion of bupivacaine to the wound environment via the ON-Q PainBuster(®) Post-op Pain Relief System (ON-Q). METHODS We randomized 27 women undergoing open gynecological surgery to receive either three XaraColl implants (each containing 50 mg bupivacaine hydrochloride) or ON-Q (900 mg bupivacaine hydrochloride perfused over 72 hours) in a 1:1 ratio. Following surgery, patients had access to intravenous morphine via a patient-controlled analgesia pump as rescue analgesia for the first 24 hours and to oral opioid medication thereafter. Total use of opioid analgesia was compared through 24, 48, 72, and 96 hours after surgery. Patients also evaluated overall pain control over the 96-hour period using a five-point numeric rating scale. Safety was assessed for 30 days after surgery. RESULTS XaraColl was non-inferior to ON-Q in total use of opioid analgesia for the first 24, 48, 72, and 96 hours after surgery, with a statistical trend towards reduced opioid use in favor of XaraColl over 24, 48, and 72 hours (P = 0.067, 0.100, and 0.089, respectively). The time to first use of opioid analgesia was also significantly delayed in patients treated with XaraColl (P = 0.024). There was no significant difference between groups in patients' evaluation of pain control or their satisfaction with the treatment in general. Both treatments were considered safe and well tolerated. CONCLUSION Despite using only 17% of the ON-Q dose, XaraColl is as effective as ON-Q in providing postoperative analgesia for 4 days after open gynecological surgery. These preliminary findings suggest that XaraColl offers great potential for the management of postoperative pain and warrants further definitive studies.