A ROLE IN PRURIGO NODULARIS?
In a separate, 127-patient study, which Dr. Sonja Ständer presented earlier in 2017 at the annual meeting of the American Academy of Dermatology, serlopitant yielded a significant reduction in pruritus vs placebo in patients with prurigo nodularis.
In the study, conducted at 15 sites in Germany, patients with a VAS pruritus score of 7 or higher were randomized to receive serlopitant 5 mg once daily or placebo for 8 weeks. At the end of that treatment period, there was a 48% reduction in average pruritus severity for the serlopitant group, versus 26% for placebo (P < 0.001).
Investigators also found a significant difference between arms in favor of the serlopitant group at Week 2 and Week 4 evaluations. Adverse events were primarily mild to moderate for serlopitant in this study, with a safety profile comparable to placebo, according to investigators.
Because there are no approved treatments for prurigo nodularis, the severe itching experienced by some patients represents an important unmet need, according to Dr. Ständer.
ATOPIC DERMATITIS AT THE FOREFRONT
The currently enrolling trial of serlopitant in atopic dermatitis will include 450 patients randomized to daily high-dose serlopitant, low-dose serlopitant, or placebo, with a primary outcome measure of itch intensity on the Numeric Rating Scale (NRS) after 6 weeks of treatment. Patients must be 13 or older and have a diagnosis of atopic dermatitis.
Being able to block the NK-1 receptor is part of the rationale for evaluating serlopitant in atopic dermatitis and other conditions associated with severe itch. According to Dr. Ständer, interactions between substance P and the NK-1 receptor play an important role in pruritus pathogenesis.
Serlopitant is not the first NK-1 antagonist to be considered as an anti-itch treatment. Aprepitant, an NK-1 receptor antagonist approved for nausea and vomiting related to chemotherapy, has also been evaluated as an anti-itch treatment in conditions including atopic diathesis, prurigo nodularis, and Sézary syndrome. While aprepitant demonstrated promising anti-itch efficacy, Dr. Ständer said its use in this capacity could possibly be limited due to potential drug-drug interactions associated with the treatment.
Dr. Ständer said that due to potential concerns regarding drug-drug interactions, she would not consider aprepitant as a long-term treatment option: “Serlopitant is more proper for long-term to use in patients with chronic pruritus,” she said. “Patients with the chronic itch may need a long term treatment for several weeks or months.”