REDWOOD CITY, Calif., Dec. 9 AcelRx Pharmaceuticals, Inc.today announced positive results from a Phase 2 clinical study evaluating thesafety and efficacy of its lead product candidate, ARX-01, for the treatmentof moderate-to-severe inpatient acute pain following knee replacement surgery.The primary endpoint evaluated pain intensity (Sum of the Pain IntensityDifference - SPID12) over the 12-hour study period compared to baseline.Results demonstrated that compared to placebo, patients receiving 15 mcg ofARX-01 experienced a statistically significant reduction in pain intensityover the study period, based on the worst observation carried forwardimputation method (WOCF), p=0.015. Additionally, at the 15 mcg dose, thestudy met an important secondary endpoint compared to placebo, the percentageof patient dropouts due to inadequate analgesia, p=0.006. Further, no seriousor unexpected adverse events related to ARX-01 were reported in the study.
ARX-01 is a sublingual formulation of the opioid pain medication,sufentanil. ARX-01 is based on the company's proprietary NanoTab(TM) dosageform, which enables delivery of sufentanil by the non-invasive oraltransmucosal (sublingual) route.
"We chose a very painful surgery in an elderly patient population toshowcase the efficacy and safety of Sublingual Sufentanil NanoTabs in treatingacute post-operative pain," said Pamela Palmer, M.D., Ph.D., chief medicalofficer of AcelRx Pharmaceuticals. "The superior attributes of both the drugand the dosage form enabled these highly encouraging Phase 2 results."
This multicenter, double-blind, randomized, placebo-controlled,dose-finding Phase 2 study evaluated the safety and efficacy of ARX-01 inpatients undergoing elective unilateral knee replacement surgery. In thestudy, 101 patients were randomized to receive either placebo or one of threedifferent dosage strengths of ARX-01: 5mcg, 10mcg or 15mcg of sufentanil.Doses were delivered sublingually as needed to treat pain with a 20-minuteminimum re-dosing interval and patients were allowed to drop out of the studyat any time. Positive results were also obtained for the primary endpointfollowing treatment with the 15mcg dose compared to placebo using twoalternate methods for imputing missing data from drop-outs: baselineobservation carried forward (BOCF), p = 0.007, and last observation carriedforward (LOCF), p = 0.018. Importantly, there were no events of clinicallysignificant respiratory depression for any dosing group. Based on thesepositive results, AcelRx intends to further advance clinical development ofARX-01 in 2009.
"We are pleased by the wonderful clinical results of our Phase 2post-operative acute pain study," said Thomas A. Schreck, chairman and chiefexecutive officer of AcelRx Pharmaceuticals. "This is the culmination of agreat deal of hard work by a team of efficient, dedicated people over the lasttwo years, and is therefore very gratifying indeed. This trial has the benefitof validating Sublingual Sufentanil NanoTabs as a robust product candidate forits initial in-hospital acute pain indication, as well as providing thefoundation of safety and efficacy for the other programs in our pipeline."
About ARX-01 Sublingual Sufentanil NanoTabs
Sufentanil is currently approved as an intravenous (IV) anesthetic and isalso indicated for epidural administration during labor and delivery. Due totheir small size, ARX-01 Sublingual Sufentanil NanoTabs are convenient,well-tolerated, have high bioavailability and provide lower peak plasma levelscompared to IV administration.
About the ARX-01 Oral Patient-Controlled Analgesia System
The ARX-01 Oral Patient-Controlled Analgesia (PCA) system is based on aproprietary pre-programmed, hand-held dispenser being developed by AcelRx.The AcelRx dispenser is designed to be hospital compliant for administrationof Sublingual Sufentanil NanoTabs, while providing features directed topatient safety and convenience.
About Acute In-Hospital Pain
Acute pain management in the hospital, in particular post-operativeanalgesia, remains a significant challenge for healthcare providers. Currenttreatment methods include IV PCA, continuous epidural infusion, as well asother regional anesthesia techniques. IV PCA relies on a computerized pumpthat is attached to a patient's IV catheter. A variety of opioids, mostfrequently morphine, may be patient-administered via the PCA pump. Theinvasive nature of IV PCA delivery and the potential for programming errorswhen setting up the pump are well-known disadvantages of this method of paincontrol.
About AcelRx Pharmaceuticals, Inc.
AcelRx Pharmaceuticals is a privately held pharmaceutical companydedicated to the development and commercialization of new therapies for thetreatment of pain and other conditions where there is an unmet need forimproved safety and efficacy. The company applies its proprietary dosage formand delivery technologies to enhance the safety, therapeutic benefit andcommercial attractiveness of currently approved compounds.
For additional information about AcelRx Pharmaceuticals visithttp://www.acelrx.com.
SOURCE AcelRx Pharmaceuticals, Inc.