Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

The safety of buprenorphine and naloxone sublingual film is supported by clinical trials using buprenorphine sublingual tablets and buprenorphine and naloxone sublingual tablets, and other trials using buprenorphine sublingual solutions, as well as an open-label study in 194 patients treated with buprenorphine and naloxone sublingual film administered sublingually and 188 patients treated with the film administered buccally. In total, safety data from clinical studies are available from over 3000 opioid-dependent subjects exposed to buprenorphine at doses in the range used in the treatment of opioid dependence. Few differences in the adverse event profile were noted with regard to sublingually and buccally administered buprenorphine and naloxone sublingual film, buprenorphine and naloxone sublingual tablets, buprenorphine sublingual tablets and a buprenorphine ethanolic sublingual solution.

The most common adverse event (> 1%) associated with the sublingual administration of the buprenorphine and naloxone sublingual film was oral hypoesthesia. Other adverse events were constipation, glossodynia, oral mucosal erythema, vomiting, intoxication, disturbance in attention, palpitations, insomnia, withdrawal syndrome, hyperhidrosis, and blurred vision.

The most common adverse events associated with the buccal administration were similar to those observed with sublingual administration of the film.

Other adverse event data were derived from larger, controlled studies of buprenorphine and naloxone sublingual tablets and buprenorphine sublingual tablets and of buprenorphine sublingual solution. In a comparative study of buprenorphine and naloxone sublingual tablets and buprenorphine sublingual tablets, adverse event profiles were similar for subjects treated with 16 mg/4 mg buprenorphine and naloxone sublingual tablets or 16 mg buprenorphine sublingual tablets. The following adverse events were reported to occur by at least 5% of patients in a 4 week study of buprenorphine and naloxone sublingual tablets and buprenorphine sublingual tablets.

The adverse event profile of buprenorphine was also characterized in the dose-controlled study of a buprenorphine ethanolic solution, over a range of doses in four months of treatment. Table 3 shows adverse events reported by at least 5% of subjects in any dose group in the dose-controlled trial.

The safety of buprenorphine and naloxone sublingual film during treatment induction is supported by a clinical trial using 16 patients treated with buprenorphine and naloxone sublingual film and 18 treated with a buprenorphine-only sublingual film. Few differences in the adverse event profiles were noted between buprenorphine and naloxone sublingual film and the buprenorphine-only sublingual film.

The most common adverse event occurring during treatment induction and the 3 days following induction using buprenorphine and naloxone sublingual film was restlessness. Other adverse events were anxiety, piloerection, stomach discomfort, irritability, headache, rhinorrhea, cold sweat, arthralgia, and lacrimation increased.

Four subjects left the study early on the first day of sublingual film administration. However, there was no evidence to suggest that any of the four subjects experienced precipitated withdrawal secondary to the administration of buprenorphine or buprenorphine and naloxone sublingual films.