Repeat treatments with Dysport associated with favorable safety

Key Points

Findings from an analysis of the long-term safety data from patients receiving repeat administrations of abobotulinumtoxinA (Dysport, Medicis) for the treatment of glabellar lines are consistent with the adverse event profile appearing in the package insert, says Ira D. Lawrence, M.D., chief medical officer and senior vice-president of research and development, Medicis, Scottsdale, Ariz.

Dr. Lawrence recently reported results from data collected in 1,414 participants in an open-label extension study who were treated over a 24-month period after completing at least one of four phase 3 clinical trials. Whether considering the types of adverse events reported, their severity or their frequency, the data were similar to those collected among about 400 patients treated with abobotulinumtoxinA in three randomized, placebo-controlled glabellar line pivotal studies.

"This updated safety analysis from a robust, larger patient database shows that with longer-term treatment, abobotulinumtoxinA continues to be well-tolerated and has not been associated with any new or cumulative safety issues. We believe this formulation is an important product for the treatment of glabellar lines and are delighted with its continued demonstration of excellent efficacy and safety since reaching the market," Dr. Lawrence says.

Study parameters

In the open-label extension study, repeat treatments with abobotulinumtoxinA were performed using either a fixed dose of 50 units (maximum eight treatments over 24 months) or a variable dose regimen (50, 60, 70 or 80 units) depending on muscle mass (maximum four treatments over 24 months). All treatments were performed with the total dose divided equally among five injection sites. Follow-up visits were scheduled at days seven, 14 and 30 after each treatment, and then monthly until the next treatment.

Adverse events

Overall, 856 (61 percent) patients experienced at least one adverse event, with no difference noted in the incidence between the fixed and variable dose groups. Almost three-fourths of all treatment-emergent adverse events were rated as mild, and only 5 percent were severe.

"Putting these data into perspective, it is important to note that adverse events are classified as severe based on the FDA (Food and Drug Administration) definition of any event that required an alteration in daily activities. The severe events included many that were felt not related to the treatment, as well as such problems as headache managed with an analgesic," Dr. Lawrence says.

Headache (7 percent) was the second-most frequently reported adverse event following nasopharyngitis (12 percent). Upper respiratory tract infection and sinusitis (6 percent each) represented the only other adverse events with a frequency greater than 5 percent.

Adverse events occurring around the eyes included eyelid ptosis (2 percent), eyelid edema (1 percent) and dry eye (1 percent). None of the cases of ptosis were severe, and almost half resolved within three weeks.

"There was no evidence of a dose-response relationship for the risks of ocular events or ptosis in particular, and, overall, the number of ptosis events decreased as the number of repeat treatments increased. Most other adverse events remained constant or in some cases decreased with ongoing use," Dr. Lawrence says.

Disclosures: Dr. Lawrence is an employee of Medicis, but he reports no other direct financial interests.