Phase III trial of ARX-04 (sufentanil sublingual tablet) shows efficacy in acute pain- AcelRx Pharmaceuticals

AcelRx Pharmaceuticals has reported topline results from the single-arm, open-label Phase III SAP302 trial (NCT02447848), which assessed ARX-04 (sufentanil sublingual tablet, 30 mcg) in patients who presented to the emergency room with moderate-to-severe acute pain associated with trauma or injury. Overall, the 76 adults treated with ARX-04 in this study experienced a mean pain intensity difference to baseline (PID) of 2.9 from a baseline of 8.1, or 35%, on a 0 � 10 numeric rating scale at 60 minutes. SAP302 enrolled patients in two cohorts.

The initial phase enrolled 40 adults who were administered a single dose of ARX-04; and an extension phase enrolled 36 adults who were eligible to receive up to four doses of ARX-04, given hourly as needed for pain. Interim results from the first cohort were reported in February 2016, and showed that patients treated with a single dose of ARX-04 experienced a mean pain intensity decrease from baseline of 2.7 at 60 minutes. Patients in the second cohort reported a mean pain intensity decrease from baseline of 3.1 on the 0 � 10 pain intensity scale at 60 minutes. Of these 36 patients, seven received a second dose of ARX-04, and two received a third dose. For 75% of patients in the second cohort, a single dose of ARX?04 was sufficient for pain relief and only 8% of patients received morphine in addition to ARX-04.

In addition, ARX-04 demonstrated a predicted onset of activity in patients enrolled in SAP302. Patients reported a mean pain intensity decrease of 1.1 compared to baseline 15 minutes following first administration of ARX-04, and a decrease of 1.9 after 30 minutes. Overall ARX-04 was well tolerated in this study, with 79% of patients reporting no adverse events. The most common adverse events reported in the study occurred with single-digit rates - the most common being nausea (9%), somnolence (5%) and vomiting (4%).

Comment: AcelRx is hoping to target its investigational non-invasive, rapid-onset analgesic for short-term treatment of pain to patients such as wounded soldiers on the battlefield, trauma victims at the site of a road-traffic accident, migraine patients in the emergency room, or for general patients in moderate-to-severe acute pain where iv access is not readily available.