Although there currently are no formal guidelines for the treatment of refractory pityriasis rubra pilaris (PRP), successful off-label treatment of the condition with multiple biologics approved for psoriasis has been reported.1,2 Secukinumab, an IL-17A antagonist, has shown particularly striking results in the treatment of PRP in 2 recent case reports.3,4 We report 2 additional cases of severe refractory PRP that responded rapidly to treatment with secukinumab. In both cases, the patients’ erythematous plaques resolved or had nearly resolved by week 4 of treatment. Our findings suggest that IL-17 plays an important role in PRP pathogenesis and support future clinical trials of anti–IL-17 agents for treatment of this entity.
A 60-year-old man with a history of biopsy-proven PRP presented with persistent generalized erythema, scattered patches of normal skin, and hyperkeratotic plaques on the bilateral palms of 1 year’s duration. Previous therapies included topical steroids, topical calcipotriene, adalimumab 40 mg once every other week, infliximab 5 mg/kg once every 8 weeks, ustekinumab 90 mg once every 12 weeks, acitretin 25 mg once daily, and most recently cyclosporine 200 mg twice daily. Of these treatments, infliximab was the only treatment that provided minimal relief; however, the patient continued to have itching and painful plaques covering approximately 20% of body surface area (Figure 1A). Infliximab was therefore discontinued and treatment with cyclosporine was started. After failure on cyclosporine, the patient was started on secukinumab, with loading doses of 300 mg injected subcutaneously once weekly for 5 weeks.
At 4 weeks’ follow-up, there was a marked decrease in erythema and scaling. The body surface area affected had decreased to 5%, and improvement of palmar keratoderma was noted. The patient continued with maintenance dosing of secukinumab 300 mg once every 4 weeks. By week 8, the erythema had fully resolved (Figure 1B), and he remained clear at week 24. No adverse events were noted since initiation of therapy.
A 74-year-old woman with a history of PRP that had previously been misdiagnosed as psoriasis by an outside physician presented for evaluation of palmoplantar keratoderma (Figure 2A), follicular hyperkeratosis, and erythematous plaques on the trunk and arms of 5 years’ duration. Previous therapies included topical steroids, topical urea, methotrexate 20 mg once weekly, adalimumab 40 mg once every other week, infliximab 10 mg/kg once every 4 weeks, ustekinumab 90 mg once every 12 weeks, and most recently acitretin 50 mg once daily.
The patient had been maintained on ustekinumab and acitretin for 2 years with only mild improvement. Ustekinumab was then discontinued, and after 3 months treatment with secukinumab was added to the once-daily acitretin. Similar to Patient 1, loading doses of secukinumab 300 mg were administered once weekly for 5 weeks. The plaques on the trunk and arms had resolved by week 4, but the palmoplantar keratoderma persisted. The patient continued with the maintenance dose of secukinumab 300 mg once every 4 weeks and reported an increase in peeling of the palms and soles at week 8.
By week 12 of treatment, the palmar keratoderma had resolved, and debridement of the soles revealed patches of normal skin (Figure 2B). By week 52, no adverse events had been noted. The patient continued to experience mild keratoderma of the soles, making us reluctant to discontinue acitretin; however, she has maintained her maximal response, and her quality of life has significantly improved. The patient was continued on acitretin and secukinumab, and her condition remained stable.