Sublingual Sufentanil Found Safe in Late-Stage Trial

Tablets administered via single-dose applicator

In an open-label phase 3 trial, the investigational product candidate ARX-04 (sufentanil sublingual tablets 30 mcg, AcelRx Pharmaceuticals) was well tolerated in the management of moderate-to-severe acute pain in postoperative patients, including elderly patients and those with organ impairment. Regardless of age and organ function, approximately two in three patients experienced no adverse events during the study (63% of all patients; 63% of those 65 years of age or older; 62% of those with hepatic impairment; and 70% of those with renal impairment). In a global assessment of ARX-04 as a method of pain control, 90% of health care professionals and 87% of patients responded that the treatment was “good” or “excellent.”

ARX-04 consists of 30-mcg sufentanil tablets delivered sublingually by a health care professional using a disposable, prefilled, single-dose applicator. Sufentanil is a synthetic opioid analgesic with a high therapeutic index and no known active metabolites.

The SAP303 trial enrolled 140 patients ages 40 years and older who were expected to have moderate-to-severe acute pain after surgery. The study’s primary objective was to study the safety of ARX-04 in the postoperative management of moderate-to-severe acute pain. Recruitment included patients 65 years of age and older, and patients with comorbidities.

The patients’ mean age was 54.7 years. During the 12-hour study period, the mean number of ARX-04 doses administered was 3.3. The mean inter-dosing interval was more than three hours (193 minutes).

Safety variables included adverse events, vital signs (i.e., blood pressure, heart rate, and respiratory rate), and oxygen saturation. The primary efficacy variable was the time-weighted summed pain intensity difference over the 12-hour study period (SPID12), and secondary efficacy variables included pain intensity by evaluation time point.

The safety results showed that, overall, there were no differences in adverse events between patients with normal and impaired liver function or between patients with normal and impaired renal function. No clinically meaningful changes from baseline in vital signs or oxygen saturation were observed, and no opioid reversal agents were needed.

The primary and secondary efficacy endpoints showed a reduction in pain intensity starting at 30 minutes after the first dose of ARX-04, followed by 27%, 49%, and 57% reductions in mean pain intensity from a baseline mean pain score of 6.2 at one hour, two hours, and 12 hours, respectively.

AcelRx intends to submit a new drug application for ARX-04 for the treatment of patients with moderate-to-severe acute pain in medically supervised settings by the end of 2016.

Source: AcelRx Pharmaceuticals; September 15, 2016.