Neurocrine is halting further development of luvadaxistat after it failed to improve cognitive impairment in patients with schizophrenia in a mid-stage study.
The company said in a Thursday update that luvadaxistat “failed to replicate the cognitive endpoints data” seen in a previous study because of “large variability” in cognitive abilities among the studied population. There was also an “imbalance in the baseline characteristics” of patients in the treatment arm, Neurocrine said.
The hope was that the new data would validate previous Phase 2 results reported in 2021, which found luvadaxistat improved cognitive ability, the trial’s secondary endpoint. But the drug failed the primary endpoint of that trial, which was improvement in negative symptoms of schizophrenia.
Negative symptoms describe schizophrenia patients withdrawing or isolating themselves from the world. Positive symptoms apply more to changes in behavior, like hallucinations.
Luvadaxistat is now absent from the company’s pipeline, according to an updated R&D chart. Since Neurocrine will “halt further development of luvadaxistat at this time,” resources will instead go toward advancing two other neuropsychiatry candidates into Phase 3, CMO Eiry Roberts said in a statement.
One such asset is NBI-1117568, which had a positive readout as a treatment for schizophrenia last month, albeit one that did not meet the company’s expectations. The company reported that the drug notched a 7.5-point improvement in schizophrenia symptoms compared to placebo, slightly less than the 8-point improvement that was hoped for.
But the treatment paradigm in schizophrenia could potentially evolve in the next few years. Bristol Myers Squibb’s recently acquired KarXT is set for an FDA decision later this month and AbbVie is advancing a schizophrenia drug it got a hold of after buying Cerevel Therapeutics.
Neurocrine expects to launch the Phase 3 study for NBI-’568 in early 2025. The company is also looking to advance its NBI-1065845 for major depressive disorder.