Cara Therapeutics’ drug candidate has flopped in a mid-stage trial in people with moderate-to-severe itch due to a neurological disorder, prompting the company to terminate the program — the last one standing in its pipeline — and look for a way out.
The biotech’s oral difelikefalin did not show a “meaningful clinical benefit” in pruritus at eight weeks compared with placebo in the dose-finding portion of the Phase 2/3 KOURAGE trial. In Part A of the study, more than 200 people with notalgia paresthetica (NP) were randomized to one of three doses of the kappa opioid receptor agonist (2 mg, 1 mg, 0.25 mg) or placebo.
On Wednesday, Stifel analysts said they were “surprised and disappointed” by the setback because lower doses of oral difelikefalin had produced “clear and compelling” data in NP at the proof-of-concept stage.
As a result of the failure, Cara is “winding down” the NP program and “exploring strategic alternatives” to boost value for its shareholders, CEO Christopher Posner said in a company release Wednesday.
The company’s share price $CARA was down 26% premarket Thursday to $0.50.
Cara had placed high hopes on the NP program as it ended a Phase 3 test of oral difelikefalin in chronic kidney disease (CKD) patients with pruritus in January. It also laid off around half its workforce, including head of R&D Frédérique Menzaghi. At the time, Posner had said that the NP indication offered the “greatest commercial potential for oral difelikefalin.”
Difelikefalin is the active ingredient in Cara’s Korsuva injection for itch in CKD patients undergoing dialysis, which it licensed to Vifor Pharma in 2020.
Korsuva was granted Transitional Drug Add-On Payment Adjustment by the US Centers for Medicare & Medicaid Services from April 2022 for two years according to an SEC filing, but this ended in April 2024. While Korsuva brought Cara $12.9 million in profit share last year, sales of the drug “can no longer be relied upon because of systemic disincentives,” Stifel analysts said.
Cara had $70 million in cash, cash equivalents and marketable securities as of March 31.
Editor’s Note: This article was updated to add information about Cara’s share price.