SINGAPORE – presented in a late-breaker session at the World Congress of Dermatology,
In the phase 2b study, patients who received the high-dose regimen (a 600-mg subcutaneous loading dose, then 300-mg SC every 4 weeks) of spesolimab experienced 84% fewer GPP fares over 48 weeks, compared with those on placebo, reported Bruce Strober, MD, PhD, Central Connecticut Dermatology, Cromwell, and clinical professor of dermatology, Yale University, New Haven, Conn. “Additionally, no flares occurred after week 4, and this, in turn, translated into improved patient outcomes.”
GPP is a rare, chronic, systemic neutrophilic skin disease. The resulting flares, characterized by painful pustules all over the body, can lead to sepsis, shock, and other life-threatening complications. “People who have it are considerably burdened by it, so targeted therapy of this disease is incredibly important because it leads to lessened morbidity and, importantly, mortality for these patients,” Dr. Strober said.
“It’s important not only to treat the flares but also to prevent them,” he noted.
The intravenous formulation of spesolimab (Spevigo) was approved for the treatment of GPP flares in adults by the Food and Drug Administration in September 2022. It is now authorized in nearly 40 countries, including Japan, China, and the European Union.
The phase 2 Effisayil 2 study presented at the meeting evaluated the subcutaneous formulation of spesolimab. Data on subcutaneous spesolimab has been submitted to the FDA, and has received breakthrough therapy designation, according to the manufacturer, Boehringer Ingelheim.
Flare prevention
In the study, 123 patients with GPP were randomly assigned 1:1:1:1 to one of four groups: high-dose spesolimab, medium-dose (600-mg SC loading dose, then 300-mg SC every 12 weeks), low-dose (300-mg SC loading dose, then 150-mg SC every 12 weeks), or placebo. In the event of a flare during the randomized treatment period, a patient was administered a single, 900-mg intravenous dose of spesolimab.
Nearly two-thirds of the participants were female and nearly two-thirds were Asian, with a mean age of about 39-43 years.
The mean numbers of GPP flares experienced annually by those in the low-, medium-, and high-dose spesolimab groups were 2.7, 1.9, and 2.4, respectively (2.4% in the placebo group). Fewer than a third had concurrent plaque psoriasis at baseline. Most (48.4%-63.3%) did not have an IL-36RN mutation.
Additionally, the Generalized Pustular Psoriasis Physician Global Assessment total score was 1 in 74.2%-93.5% of participants, and 0 in the remainder.
The primary study endpoint was the time to GPP flare by week 48. The risk of developing a flare among those on high-dose spesolimab was 84% lower, compared with that of those on placebo (hazard ratio, 0.16; 95% confidence interval, 0.05-0.54; P = .0005). No patients on the high dose had a flare after the 4th week of the study.
Similarly, for the secondary endpoint (occurrence of at least one GPP flare by week 48). Dr. Strober and his colleagues reported that high-dose spesolimab was superior to placebo with a risk difference of -39% (95% CI, –0.62 to –0.16; P = .0013). By contrast, the risk differences for the medium- and low-dose spesolimab arms were –0.23 (95% CI, –0.46 to 0.01) and -0.31 (95% CI, –0.54 to –0.08), respectively.
The safety profile of subcutaneous spesolimab across all three doses was similar to that of placebo, and there was no dose-dependent trend. Reported adverse events (AEs) were mild. There were five (5.4%) AEs leading to discontinuation of the drug in the medium- and high-dose groups, but none in the low-dose group. Overall, there were nine (9.7%) serious AEs reported in the spesolimab groups, and three (10%) in the high-dose group; no deaths occurred on any dose.
Participants most often reported injection-site erythema, reported in 13 (14%) of the patients on spesolimab versus 1 (3.3%) of those on placebo.
“Overall, the study demonstrates that subcutaneous spesolimab is effective at controlling GPP flares, especially at a high dose relative to placebo, and supports subcutaneous spesolimab for the therapy for GPP flare prevention,” Dr. Strober said at the meeting.