Imsidolimab showed ‘rapid and sustained’ activity in generalized pustular psoriasis

Key takeaways:

• Imsidolimab yielded a response rate of 75% at 16 weeks in patients with generalized pustular psoriasis.
• No serious treatment-related adverse events were reported for the drug.

Three-quarters of patients with generalized pustular psoriasis demonstrated response to treatment with an interleukin-36-targeted therapy as early as 4 weeks, according to a study.

“Generalized pustular psoriasis (GPP) is a systemic inflammatory disease that can be severe, debilitating, and life-threatening,” Richard B. Warren, BSc, MBChB, MRCP, PhD, professor of dermatology and therapeutics and honorary consultant dermatologist at The University of Manchester, United Kingdom, and colleagues wrote.

The researchers suggested that uncontrolled activation of interleukin-36 (IL-36) pro-inflammatory activity may play a role in GPP pathogenesis.

In the open-label, single-arm, multiple-dose study, eight patients with GPP underwent treatment with the anti-IL-36 receptor antibody imsidolimab (AnaptysBio). The medication was assessed for efficacy, safety and tolerability.

Study protocols called for a dose of imsidolimab delivered intravenously at 750 mg on day 1. On days 29, 57 and 85, the drug was administered subcutaneously at a dose of 100 mg.

Clinical response as measured by the Clinical Global Impression (CGI) scale at weeks 4 and 16 served as the primary efficacy outcome.

Six patients completed the study.

The first responses were observed by day 3. Pustulation relative to other manifestations of GPP began to respond at this time point.

By weeks 4 and 16, 75% of patients experienced a treatment response, with 50% of these responders considered “very much improved,” according to the researchers.

Response persisted through days 8, 29 and 113.

Safety data showed that 75% of the cohort reported a treatment-emergent adverse event. Most were mild or moderate. Of the two serious events, only one was possibly related to treatment. There were no discontinuations due to treatment and no fatalities overall.

“Imsidolimab demonstrated a rapid and sustained resolution of symptoms and pustular eruptions in subjects with GPP,” the researchers concluded. “It was generally well-tolerated, associated with acceptable safety, and is advancing to phase 3 trials.”

These findings argue for ongoing investigation into the IL-36 pathway in the GPP setting, they added.