REDWOOD CITY, Calif., Feb. 26, 2020 (GLOBE NEWSWIRE) -- Menlo Therapeutics Inc. (Nasdaq: MNLO), a late-stage biopharmaceutical company, today announced results from its Phase 2 clinical trial evaluating the safety and efficacy of once daily oral serlopitant for the treatment of chronic pruritus (itch) of unknown origin (CPUO). The trial, which included 233 patients, did not meet its primary endpoint to show a statistically significant reduction in pruritus in patients treated with serlopitant compared to placebo based upon a 4-point improvement responder analysis. In the trial, 37.9% of patients in the serlopitant group (N=116) achieved a 4-point or greater improvement on the worst-itch numeric rating scale, or WI-NRS, at week 10 compared to baseline (primary efficacy endpoint) versus 39.3% of patients treated with placebo (N=117). There were no meaningful differences observed between the serlopitant and placebo groups in the prospectively-defined secondary endpoints.

“We conducted this trial in CPUO in the hope of offering the first-ever approved therapy for patients suffering from severe pruritus associated with this condition,” said Steve Basta, chief executive officer of Menlo Therapeutics. “We were surprised to see a placebo response significantly larger than observed in our prior studies. The higher placebo response rate may be due to characteristics of the CPUO population, which is not well understood clinically.”

The Phase 2 multicenter, placebo‑controlled double‑blind clinical trial enrolled 233 patients with self-reported CPUO, who experienced pruritus for at least six months prior to enrollment with no identified underlying cause for the pruritus. This trial compared treatment with serlopitant versus placebo for 10 weeks.

Serlopitant was well-tolerated. The frequency of treatment-emergent adverse events assessed as likely related to treatment were 10.3% in the serlopitant group versus 2.6% in the placebo group. The most frequently reported adverse events in the serlopitant group were diarrhea (6.9%), somnolence (5.2%), fatigue and headache (2.6% each). The most frequently reported adverse events in the placebo group were gastroesophageal reflux disease and arthralgia (2.6% each). Two serlopitant-treated subjects reported a total of three serious adverse events which were deemed to not be related to study drug. To date, serlopitant has been administered to over 2,000 individuals, including patients who have received treatment for up to one year.

Results from the company’s Phase 3 trials for the treatment of pruritus associated with prurigo nodularis (PN) are expected in March or April of this year.

Conference Call Information

Menlo will host a conference call today at 8:30 am ET, and will be joined by Foamix’s chief executive officer, David Domzalski. To participate in the live conference call, please call 877-253-4330 (toll-free) or 706-643-0896 (toll) and reference call ID number 2083065. A live webcast of the call can also be accessed by visiting the “Investor” section of the company’s website at An archived replay of the call will be available for 60 days following the call by dialing 855-859-2056 (toll-free) or 404-537-3406 (toll) and referencing call ID number 2083065.

About Chronic Pruritus of Unknown Origin

CPUO is typically defined as pruritus lasting 6 weeks or longer, where the underlying cause is unclear. It is also sometimes referred to as idiopathic pruritus or pruritus of undetermined origin. No therapy has been previously developed to treat pruritus in these patients, despite the significant unmet need for such treatment and the notable prevalence of this condition. Menlo Therapeutics’ market research indicates approximately two million patients may have CPUO in the U.S.

About Serlopitant

Serlopitant is a small molecule, highly selective NK1 receptor antagonist. Two critical mediators of the urge to scratch are Substance P, or SP, and its receptor, the neurokinin-1 receptor, or NK1 receptor. SP is a naturally occurring peptide in the tachykinin neuropeptide family. Tachykinins have a broad range of functions in the nervous and immune systems. SP binding of NK1 receptor has been shown to be a key mediator of sensory nerve signaling, including the itch-scratch reflex and the vomiting reflex.

About Menlo Therapeutics

Menlo Therapeutics Inc. is a late-stage biopharmaceutical company focused on the development of serlopitant, a once-daily oral NK1 receptor antagonist, for the treatment of pruritus. Menlo Therapeutics is expected to merge with Foamix in early March 2020.

Forward-Looking Statements

To the extent that statements contained in this press release are not descriptions of historical facts regarding Menlo Therapeutics, they are forward-looking statements reflecting the current beliefs and expectations of management made pursuant to the safe harbor of the Private Securities Reform Act of 1995, including, but not limited to, statements regarding the potential safety and efficacy of serlopitant for the treatment of various conditions, expectations with respect to the anticipated announcement of results of its clinical trials for pruritus associated with prurigo nodularis and the expected timing of the closing of the merger with Foamix. Such forward-looking statements involve substantial risk and uncertainties that could cause Menlo Therapeutics’ development program for serlopitant, future financial results, achievements or performance to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, risks that the timing of results, enrollment or commencement of clinical trials may be delayed, despite prior successfully completed clinical trials or do not demonstrate efficacy of serlopitant in the studied indications, the risk of adverse safety events, risks resulting from the unpredictability of the regulatory process and regulatory developments in the United States and foreign countries and risks that the closing conditions for the merger may not be satisfied. These factors, together with those that are described in greater detail in Menlo Therapeutics’ Quarterly Report on Form 10-Q to filed on October 31, 2019, as well as any reports that it may file with the SEC in the future, may cause Menlo Therapeutics’ actual results, performance or achievements to differ materially and adversely from those anticipated or implied by our forward-looking statements. Menlo Therapeutics undertakes no obligation to update or revise any forward-looking statements.

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