A setback, but not for long
Serlopitant misses primary and secondary efficacy endpoints, but Menlo continues with development program
Register for free to listen to this article
Listen with Speechify
0:00
5:00
REDWOOD CITY, Calif.—April presented some disappointing news for biopharmaceutical company Menlo Therapeutics Inc., which reported top-line results from MTI-103 (ATOMIK), its Phase 2 clinical trial of serlopitant. The study did not meet its primary or key secondary efficacy endpoints, with no statistically significant difference seen between the serlopitant-treated groups and the placebo group. Serlopitant is a once-daily oral NK1 receptor antagonist being developed for the treatment of refractory chronic cough and for pruritus associated with various dermatologic conditions. The drug candidate was originally developed by Merck, and Menlo licensed it in 2012. Thus far, more than 1,300 patients have been treated with serlopitant.
ATOMIK was a multicenter, randomized, placebo-controlled Phase 2 clinical trial evaluating the safety, efficacy and tolerability of serlopitant. A total of 484 individuals, aged 13 years or older, were enrolled with a past or present diagnosis of atopic dermatitis pruritus for a minimum of six weeks and an average weekly worst-itch numeric rating scale, or WI-NRS score ≥6 for each of the two weeks of the screening period, as recorded in the eDiary. Patients were randomized to receive once-daily doses of either 1 mg serlopitant, 5 mg serlopitant or placebo. The primary efficacy analysis was based on the difference between serlopitant and placebo in the mean change in WI-NRS from baseline to week 6, with a key secondary endpoint being a responder-rate analysis of a 4-point WI-NRS improvement at week 6.
“While we are disappointed that the results in this Phase 2 trial of pruritus associated with atopic dermatitis did not reach statistical significance and did not show the same magnitude of treatment effect as in our prior pruritus studies, we do see in the results a pattern that shows numerical improvement in each serlopitant treatment group above the placebo group at every timepoint. This is our third pruritus study of serlopitant. Reduction of pruritus has been demonstrated in two prior Phase 2 studies, one trial in patients with chronic pruritus and one trial in patients with prurigo nodularis,” Steve Basta, CEO of Menlo Therapeutics, said in a press release. “We are initiating Phase 3 studies in prurigo nodularis this quarter, and we are looking forward to the Phase 2 results in refractory chronic cough in the fourth quarter of this year, and the Phase 2 results in pruritus associated with psoriasis by late 2018 or early 2019.”
There was positive news from the study as well, however. Serlopitant was found to be well tolerated, with no serious adverse events deemed as likely related to the drug. The treatment-emergent adverse events considered as possibly related to serlopitant treatment were seen in all three cohorts with similar frequency—9.5 percent for placebo, 7.5 percent for 1 mg serlopitant and 8.1 percent for 5 mg serlopitant. The treatment-emergent adverse events that were reported in more than 5 percent of patients were worsening of atopic dermatitis—3.2 percent for placebo, 1.3 percent for 1 mg and 5.6 percent for 5 mg—and worsening of pruritus, 5.1 percent for placebo, 5.6 percent for 1 mg and 1.9 percent for 5 mg.
Menlo remains optimistic about ongoing development for the drug, with Basta noting in the company’s recent conference call that “We’re confident, based upon the prior Phase 2 studies, that serlopitant has a clear beneficial impact on pruritus. While serlopitant did not show the same magnitude of treatment effect in this study as in our prior studies, our confidence in the drug from those prior studies remains unchanged, and we really view this result as an atopic dermatitis-specific result in this trial.”
Along those lines, Basta reported in the call that the company is preparing for the process of submitting a New Drug Application for serlopitant, having initiated a “52-week multicenter, open-label safety study that is intended to expand the long-term chronic use safety database for serlopitant to support our 2020 planned NDA timeline.”
“Our goal remains to file an NDA in 2020,” he added in the call. “Each of our three indications—prurigo nodularis, refractory chronic cough and psoriasis—will be on-track with the potential of being NDA-ready in 2020, although we would caution that it’s unlikely to file all three, as the cough indication would go to a different review division than the two pruritus indications, so it would be difficult to file all three simultaneously.”