A Merck drug with new approach to chronic cough Refuse By the FDA as the agency called on the company to provide more information on the efficacy of the product candidate.
Merck said Monday that the FDA’s full response letter spelled out the request for more data. These letters are not public documents. According to the Kenilworth, N.J.-based pharma giant, the agency has not expressed concerns about the safety of the experimental drug. Merck said it was reviewing the letter and planned to meet with the agency to discuss it.
Chronic cough is a cough that lasts more than eight weeks. These coughs affect about 5 percent of U.S. adults, according to Merck. In some cases, these patients’ coughs did not respond to treatments for underlying conditions, such as asthma or gastroesophageal reflux. This type of cough is called refractory chronic cough. In other cases, the cause of the cough cannot be determined. There are no FDA-approved treatments for either cough.
Gefapixant is a small molecule designed to selectively block P2X3 receptors in the airways, related to cough mechanism. Merck’s drug application is based on results from two Phase 3 clinical trials that enrolled patients with refractory chronic cough or chronic cough of unknown cause. The studies evaluated two doses: 45 mg twice daily and 15 mg twice daily. In the high-dose group, Merck reported a significant reduction in cough frequency compared with placebo at 12 weeks. In either of the two phase 3 studies, the lower doses did not meet efficacy targets.The clinical trial results are came up with 2020 at the virtual European Respiratory Society International Congress.
Merck through Acquired in 2016 Incoming drugs. The pharma giant paid $500 million up front and committed an additional $750 million to hit milestones. Last week, gefapixant was approved in Japan for the treatment of refractory or unexplained chronic cough, where it will be marketed under the name “Lyfnua.” Gefapixant is still undergoing regulatory scrutiny in other markets.
“We remain committed to advancing gefapixant for patients with refractory or unexplained chronic cough and will work with the FDA to address the agency’s feedback,” said Roy Baynes, senior vice president and head of global clinical development and chief medical officer at Merck Research Laboratories. ” in a prepared statement. “We believe that there is an unmet need to help patients manage chronic cough because there are no specific treatment options for this condition in the United States.”
Merck has competitors chasing chronic cough treatments, some targeting P2X3.Last summer, Bayer report Its experimental small molecule eliapixant, which targets P2X3, met the primary goal of an interim study evaluating the drug’s efficacy in patients with refractory chronic cough. Bellus Health’s P2X3-targeting small molecule BLU-5937 also posted strong mid-stage clinical trial results. The Laval, Quebec-based biotech company expects to begin a Phase 3 clinical trial in the second half of this year. A once-daily formulation of the drug is in preclinical development.
There are other companies developing chronic cough medicines with different targets. New Haven, CT-based Trevi Therapeutics’ small molecule Haduvio blocks mu opioid receptors and activates kappa opioid receptors to address chronic cough associated with idiopathic pulmonary fibrosis (IPF), a lung disease . Algernon Pharmaceuticals aims to treat chronic cough by repurposing efendil, an older Sanofi drug that the pharmaceutical giant has commercialized to treat peripheral circulatory disorders. The biotechnology is in the early stages of development for the treatment of chronic cough associated with IPF. Startups have also joined the ranks.GlaxoSmithKline spin-off Nerre Therapeutics is developing orvepitant, a small molecule that blocks neurokinin-1 receptors, as a treatment for chronic cough associated with IPF.
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