AcelRx Makes Headway With Second Pain Drug-Device Combo
This article was originally published in Scrip
With its lead drug candidate Zalviso in US FDA limbo, AcelRx Pharmaceuticals is focused on its other late-stage pain drug ARX-04, a health care professional-administered sublingual tablet that delivered fast relief of moderate-to-severe post-surgical pain for patients enrolled in a Phase III clinical trial.
The Redwood City, California-based company plans to initiate a second Phase III trial during the third quarter of this year that will enroll patients admitted to hospital emergency rooms. AcelRx chief financial officer and head of business development Tim Morris told Scrip that data from the second late-stage study may be available in early 2016, and he said the FDA has not indicated that any further Phase III studies will be required to support the agency's approval of ARX-04.
ARX-04 delivers a 30mcg tablet of the opioid pain drug sufentanil in a small handheld device operated by health care providers, while Zalviso is a 15mcg dose of sufentanil that's delivered in a patient-controlled handheld device. The FDA rejected AcelRx's original new drug application (NDA) for Zalviso and requested another Phase III clinical trial to support its approval, but resubmission of the NDA is on hold while the company attempts to negotiate a path forward with the agency.
ARX-04 Moves Ahead
The first set of Phase III results for ARX-04 justified initiation of AcelRx's planned second Phase III trial. The primary endpoint in the first Phase III study was the difference in pain reduction compared with placebo as measured by the summed pain intensity difference over the first 12 hours after treatment (SPID-12). Patients were treated with ARX-04 or a placebo following abdominal surgery.
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There were two serious adverse events that led to discontinuation of participation in the study, but both occurred in the study's placebo arm. The percentage of patients who discontinued treatments during their first 24 hours in the study was much lower in the ARX-04 group than in the placebo group (3.7% versus 18.5%, p=0.002). Nausea, headache and vomiting were the most common side effects in both the ARX-04 and placebo groups.
Detailed Phase III post-surgery results will be presented during the American Society of Anesthesiologists Annual Meeting from Oct. 24 to 28 in San Diego.
Beyond Abdominal Surgery
AcelRx interim CEO Howie Rosen noted in a statement from the company that in addition to the post-surgery setting "ARX-04 has broad application in emergency room and military settings, where patients often do not have access to [intravenous] pain medications." Rosen also noted that "we are researching other medically supervised settings in which ARX-04's non-invasive, rapid-acting profile would benefit patients."
AcelRx entered into an agreement with the US Army Medical Research and Material Command (USAMRMC) in May under which the US Department of Defense (DOD) will provide partial funding of up to $17m for the ARX-04 development program.
The company said its drug-device combination product is ideal for battlefield settings where IV pain medications aren't available and intramuscular injections of morphine often are ineffective. AcelRx is not required to conduct a battlefield study under the military agreement.
Jefferies analyst Biren Amin said the first set of Phase III results for ARX-04 represent "a positive development for [AcelRx] to diversify its product portfolio beyond Zalviso," and he estimated that an NDA for the drug-device product could be filed before the end of 2016, assuming the second set of Phase III data for ARX-04 are positive early next year.
Sagient Research noted in a Sept. 9 BioMedTracker report that if the Phase III emergency room-based study is successful, "we expect ARX-04 to be approved for a broader moderate-to-severe acute pain label."