A committee of outside clinical trial observers has recommended that Praxis Precision Medicines stop testing its experimental treatment for essential tremor after an interim analysis of one study concluded it is unlikely to succeed. Instead, Praxis is continuing that test and a second one, adding that a decision about an FDA submission will be made after a final analysis of both studies.
The two separate and simultaneous studies are part of the Phase 3 trial design for the Praxis drug, ulixacaltamide. Both placebo-controlled studies are evaluating the once-daily pill over the course of 12 weeks. The main efficacy goal is assessing patients according to a composite scale that measures the ability to perform tasks of daily living.
Essential tremor leads to involuntary shaking and trembling in arms and hands, though it can also affect a patient’s head and voice. An estimated 7 million patients in the U.S. have the neurological disorder, whose exact cause is unknown. The first line of essential tremor therapies for beta blockers. While such drugs were developed for high blood pressure, they are thought to also block nerve impulses to the muscles. Anti-seizure drugs offer an alternative treatment option.
Ulixacaltamide is a small molecule inhibitor of T-type calcium channels. It’s designed to block abnormal neuronal burst firing in the cerebello-thalamo-cortical (CTC) circuit, which is correlated with tremor activity. Boston-based Praxis said Friday that based on the results of a planned interim analysis, the trial’s independent data monitoring committee recommended that Study 1 be stopped for futility, “due to the results being unlikely to meet the primary efficacy endpoint under the parameters set by the statistical model.”
The targeted total enrollment of the two studies is 600 participants. Praxis said that given the advanced state of trial enrollment, it has decided to complete both studies. Preliminary results are expected in the third quarter of this year. Praxis added that the committee said some underlying assumptions of the statistical model might have influenced the futility finding and it encouraged the company to explore alternative analysis methods.
In the Praxis announcement, CEO Marcio Souza said the company will explore different analysis methods for the final dataset that will be the basis for deciding whether to proceed with a regulatory submission. But investors took a dim view of the Praxis drug’s prospects. The biotech’s stock price tumbled Friday, closing at $38.60, down 40.6% from the Thursday’s closing price.
Ulixacaltamide came from Cerebrum, Praxis’s proprietary technology for discovering small molecule drugs with the potential to treat central nervous system disorders. Formerly known as PRAX-944, ulixacaltamide is the most advanced drug candidate in the Praxis pipeline. Other drug candidates are in earlier stages of clinical development for various forms of epilepsy.
In its report of fourth quarter and full year 2024 financial results posted on Friday, Praxis stated it finished 2024 with $469.5 million in capital, a strong cash position that follows stock offerings completed last year. The company expects its cash will support operations into 2028.
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