Specialty pharmaceutical company AcelRx Pharmaceuticals' dose-finding Phase II study of ARX-04 has met its primary endpoint.
ARX-04 is a rapid-onset, investigational single-dose sublingual sufentanil NanoTab, designed to treat acute pain.
According to the data, patients in the 30mcg sufentanil NanoTab treatment group experienced significantly greater reduction in pain, as measured by Summed Pain Intensity Difference to baseline during the 12-hour study period (SPID-12), compared to placebo.
AcelRx Pharmaceuticals chief medical officer Dr Pamela Palmer said the goal of the programme was to measure the effective sublingual sufentanil dose administered less frequently by a healthcare professional than the patient-administered ARX-01 product candidate.
"There is a need for a non-invasive, rapid-onset strong analgesic to provide short-term treatment of pain for the wounded soldier on the battlefield, the trauma victim at the site of a road-traffic accident, the migraine patient in the emergency room, or in general for patients in moderate-to-severe acute pain where intravenous access is not readily available," Palmer said.
A total of 101 patients following bunionectomy surgery were randomised in 2:2:1 ratio to 30mcg sufentanil, 20mcg sufentanil or placebo treatment arms in the study.
91% of patients completed the full 12-hour study period before entering the study.
SPID-12 scores for 30mcg sufentanil-treated patients were +6.53 and for placebo-treated patients -7.12, meaning the difference between the two groups was statistically significant.
The 20mcg sufentanil-treated patients failed to achieve SPID-12 scores that differentiated from placebo.
The study observed mild-to-moderate adverse events, while two serious adverse events of post-surgical infection that were unrelated to the study drug were reported.