LEO Pharma A/S presented results from the Phase 3 PSO-LONG clinical tria, which compared the efficacy and safety of twice-weekly Enstilar (calcipotriene and betamethasone dipropionate) Foam versus foam vehicle for long-term (52-week) maintenance treatment for adult patients with plaque psoriasis.Results were presented as ePosters online at the American Academy of Dermatology (AAD) Virtual Meeting Experience (VMX) 2020.

Use of twice-weekly Enstilar (calcipotrieneand betamethasonedipropionate) Foam as a long-term maintenance treatment is investigational and is not approved in any country, and safety and efficacy are currently being evaluated by regulatory authorities.

Enstilar (calcipotrieneand betamethasonedipropionate) Foam met the primary endpoint in the PSO-LONG trial by prolonging time to first relapse versus foam vehicle (56 days vs. 30 days).

“These results, as demonstrated by the primary endpoint, introduce new clinical data for the treatment of adult patients with plaque psoriasis,” says Mark Lebwohl, MD, Waldman Chair of Dermatology at the Icahn School of Medicine at Mount Sinai in New York City and Principal Investigator for the PSO-LONG trial. “This first-of-its kind year-long study and resulting data demonstrate that the fixed-dose combination of calcipotriene and betamethasone dipropionate foam both reduced relapses and increased the number of relapse-free days versus foam vehicle.”

Safety was evaluated as effects on calcium homeostasis and on hypothalamic-pituitary-adrenal (HPA) axis with long-term use of twice-weekly calcipotriene and betamethasone dipropionate foam, among other safety assessments. No clinically relevant effects on calcium metabolism or the HPA axis were observed. The rate of adverse events (AEs) was comparable across treatment groups.

“Our vision in psoriasis is to provide prescription solutions for patients with all severities of psoriasis,” says Kim Kjoeller, MD, Executive Vice President, Global Research & Development, LEO Pharma. “Our diverse pipeline of innovative late-stage drug candidates aims to support a range of treatment options for people living with psoriasis and other chronic skin conditions across the globe.”

The AAD VMX 2020 featured three ePosters highlighting efficacy, safety and open label data from the Phase 3 PSO-LONG trial:

• Long-term proactive management of psoriasis vulgaris with fixed-dose combination of calcipotriene 0.005% and betamethasone dipropionate 0.064% foam: results of a Phase III randomized controlled trial
• Safety of long-term proactive management with fixed-dose combination calcipotriene 0.005% and betamethasone dipropionate 0.064% foam in patients with psoriasis vulgaris: results of a Phase III, multicentre, randomized, 52-week, vehicle-controlled trial
• Results from the open-label treatment period of a long-term proactive management phase III trial using fixed-dose combination calcipotriene 0.005% and betamethasone dipropionate 0.064% foam

About PSO-LONG: Trial Design and Outcomes

The PSO-LONG trial (NCT02899962) is a 12-month, international, multi-center, randomized, vehicle-controlled, double-blind, two-arm, parallel group trial comparing the safety and efficacy combination calcipotriene 0.005% and betamethasone dipropionate 0.064% foam with foam vehicle used twice weekly as long-term maintenance treatment in adults with psoriasis vulgaris (plaque psoriasis).

Six-hundred fifty patients aged 18 or older were included in a four-week open label phase where each received once-daily calcipotriene and betamethasone dipropionate foam. Eighty percent (521 patients) achieved treatment success (Physician Global Assessment [PGA] “clear”/”almost clear” with a minimum two-grade improvement from baseline) and were then randomized 1:1 to twice-weekly administration of either calcipotriene and betamethasone dipropionate foam or vehicle foam for 52 weeks. In both arms, patients with relapse received once-daily calcipotriene and betamethasone dipropionate foam for four weeks. Fully 82 percent of patients had a PGA score of ‘moderate’ at baseline and 251 randomized patients (46 percent) completed the long-term study.

To have participated in the trial, patients must have been 18 years of age or older, had truncal and/or limb psoriasis involving two to 30 percent of body surface area, and PGA greater than or equal to mild and modified psoriasis area, and a severity index score (mPASI) of greater than or equal to two at first visit.

Results:

• The median time to first relapse was 56 days for calcipotriene and betamethasone dipropionate foam vs. 30 days for foam vehicle.
• Risk of first relapse was 43 percent lower with calcipotriene and betamethasone dipropionate foam vs. foam vehicle (HR, 0.57; 95% CI, 0.47-0.69; p<0.001).
• Rate of relapse over one year was 46 percent lower for the calcipotriene and betamethasone dipropionate foam group vs. the foam vehicle group (95% CI, 37-54%; p<0.001).
• Rate of serious AEs per 100 patient-years was comparable (8.3, calcipotriene and betamethasone dipropionate foam [n=272]; 7.9 foam vehicle [n=273]), as was rate of treatment-related AEs (2.8, calcipotriene and betamethasone dipropionate foam [n=272]; 4.5 foam vehicle [n=273]).