Ventyx Biosciences’ Crohn’s disease medicine did not help patients achieve remission in a phase 2 trial, sending the California biotech’s shares down over 20% at the open of Monday trading.
The company was testing the allosteric TYK2 inhibitor VTX958 in 109 patients who have moderately to severely active Crohn’s disease in the mid-stage trial. Patients received one of two doses of the therapy or placebo for 12 weeks, followed by a long-term follow-up. The trial was monitoring for a change in the Crohn’s disease activity index, a common rating scale measuring the severity of the inflammatory disease, from baseline to week 12.
The trial was not successful on the primary endpoint, which Ventyx attributed to “a higher than anticipated placebo response.”
As a result, Ventyx will not conduct additional testing of VTX958 with internal resources, according to the Monday release.
VTX958 did lead to a dose-dependent effect on the key secondary endpoint of endoscopic response, which the company said is “an objective outcome and a high-priority treatment goal.” Both doses also showed a decrease in two key markers of inflammation.
Ventyx intends to conduct further analysis of the data to figure out why the endoscopic and symptomatic results differed so much.
The company’s shares had dropped 23% to $2.48 by 9.46 am ET on Monday compared to $2.95 at the previous close.
Ventyx had $279.7 million in cash available as of June 30, which is expected to stretch into the second half of 2026.
This is the latest trouble VTX958 has caused Ventyx, after a mid-stage study of patients with psoriasis produced mixed results across the dosing groups in November 2023. Ventyx concluded that “the magnitude of efficacy observed did not meet our internal target to support advancement of VTX958 in plaque psoriasis.”
The company ended development in that indication and psoriatic arthritis, shifting focus for the asset onto the Crohn’s trial that was still enrolling at the time. The psoriasis failure sent Ventyx’s shares down 73% to $3.77.
Ventyx responded by laying off 20% of staff a month later. At the time, CEO Raju Mohan, Ph.D., called the indication “a much bigger opportunity.”
With VTX958 out of the running, Ventyx has three other meds in the pipeline, including VTX002 for ulcerative colitis. The company has completed a phase 2 test already and said in May that it would be seeking partners for late-stage development.