“It’s got a little bit of baggage, though,” she continued. “It’s pregnancy Category X, so you have to make sure a woman who is or may become pregnant is not using it. And there are some side effects. It can be tough to use. When you use it in psoriasis you can get local irritation up to 30% of the time.”
The two parallel phase 3 randomized trials plus a separate phase 2 study, all of which Dr. Stein Gold was involved in, showed that the efficacy of the investigational halobetasol/tazarotene fixed combination was greater than either component alone, side effects were minimized, and efficacy remained durable 4 weeks after the 8-week treatment course ended.
The not-yet-published phase 3 trials included 418 patients with moderate to severe psoriasis randomized 2:1 to once-daily application of halobetasol/tazarotene or its vehicle for 8 weeks. Treatment success, defined as at least a two-grade improvement from baseline in Investigator’s Global Assessment score plus a score of clear or almost clear, was documented at 8 weeks in 35.8% of the halobetasol/tazarotene group in one study and 45.3% in the other, compared with 7% and 12.5% of controls, respectively.
In addition, after 8 weeks, affected body surface area was reduced by a mean of 32.8% in one study and by 42.5% in the other. There was also at least a two-grade improvement in plaque erythema at the target lesion site in 42.2% and 49.6% of halobetasol/tazarotene–treated patients in the two trials. A two-grade improvement in plaque elevation was noted in 59.3% and 59.7% of patients, while for plaque scaling, the figures were 59.4% and 62.9%.