Fentanyl Sublingual Spray Safe for Long-Term Use

HONOLULU, HI—Fentanyl sublingual spray is generally safe and well tolerated for long-term use in opioid-tolerant patients with cancer for the treatment of breakthrough pain, study investigators at the American Pain Society's 31st Annual Scientific Meeting reported.

In an extension of a Phase 3, double-blind, placebo-controlled trial, Lisa Stearns, MD, from The Center for Pain and Supportive Care, Scottsdale, AZ, and colleagues evaluated the efficacy and long-term safety of fentanyl sublingual spray in a 90-day open-label, maintenance period. Patients who completed the initial double-blind trial could enroll into the open-label maintenance period at their current optimal dose. De novo patients were also enrolled and titrated to an optimal dose (100–1,600mcg) that provided effective analgesia for two consecutive breakthrough cancer pain episodes.

Ninety continuing patients entered the maintenance period. Of 229 de novo patients, 184 (80.3%) completed titration and 179 (78%) moved into the maintenance period. A total of 269 patients entered the maintenance period and 163 (60.6%) completed the study. The median dose was 600mcg.

Adverse events were recorded at all visits. During titration, 59% of de novo patients reported ≥1 adverse event, most common were nausea (13.1%), vomiting (11.8%), and somnolence (10%). Of these patients, 32% reported possible treatment emergent adverse events due to fentanyl sublingual spray. During the maintenance period, 80.7% of all patients reported ≥1 adverse event, most commonly malignant disease progression (24.2%), vomiting (16.0%), and peripheral edema (11.5%). In 24.5% of patients, these adverse events were considered at least possibly related to study medication.

Eighty-nine deaths were recorded, but only 1 (due to cardiac arrhythmia), was considered possibly related to fentanyl sublingual spray. Serious adverse events other than death were reported in 6.1% and 11.9% of patients in each period and were most commonly related to underlying cancer.

With respect to patient satisfaction with medication, more patients reported side effects associated with taking previous medications for breakthrough cancer pain (45%) than with using fentanyl sublingual spray (20%-28%) and patient satisfaction was greater with fentanyl sublingual spray than with previous medications for breakthrough cancer pain.