MedWire News: The efficacy of some formulations of clobetasol propionate is limited by their labeling restrictions, research suggests.

Ointment is thought to be the most clinically effective formulation of clobetasol propionate, but psoriasis patients often prefer to use foams and solutions over ointments and creams.

“Thus, in a clinical situation where patient preference may affect compliance, the choice of drug vehicle/formulation may impact the observed treatment outcome,” say Lori Johnson (Galderma Laboratories LP, Fort Worth, Texas, USA) and colleagues.

As reported in the Journal of Dermatological Treatment, the team compared two clobetasol propionate formulations that are reportedly popular with patients: a foam and a spray. Both the formulations contained 0.05% clobetasol propionate.

The 77 moderate-to-severe psoriasis patients were randomly assigned to apply the foam or spray twice-daily in accordance with the drug labeling, which dictates 2 weeks of foam treatment and up to 4 weeks of spray treatment.

After 2 weeks of treatment, patients using both formulations had significant improvements in their condition, achieving 33.3% and 25.0% reductions in affected body surface area (BSA) with the spray and foam, respectively.

The drug labeling prohibited further use of foam at this point, but an additional 2 weeks of spray use resulted in an overall reduction of 63.6% in affected BSA.

“Thus, while both of the advanced formulations contain the same active ingredient at the same concentration, clinically meaningful differences in treatment outcomes were observed among two preparations in this comparative study related to length of approved treatment,” the team concludes.

Free abstract