Praxis Precision Medicines saw its shares plummet 40% on Friday after announcing that an independent data monitoring committee (IDMC) recommended stopping Study 1 of its Essential3 programme for ulixacaltamide (PRAX-944). The candidate, which targets T-type calcium channels to block abnormal neuronal burst firing in essential tremor, is unlikely to meet its primary efficacy endpoint, according to an interim analysis of the trial.However, Praxis says it still plans to bring both Study 1 and Study 2 of the programme to completion, with top-line results expected in the third quarter. It cited "advanced state of enrollment" and IDMC suggestions that "underlying assumptions of the statistical model might have influenced this outcome" as reasons for continuing the studies.Final dataset in Q3"We are disappointed with and surprised by the outcome of the interim analysis for Study 1," remarked CEO Marcio Souza. "Following the advice of the committee, we will explore different analysis methods for the final dataset, which is expected in the third quarter of 2025."Ulixacaltamide is the company's most advanced programme, and Praxis had anticipated a regulatory filing this year. The drug showed "meaningful improvement" in TETRAS Activities of Daily Living (ADL) measures among patients receiving propranolol, according to results from the Phase II Essential1 trial published in the journal Neurology last year.While Praxis reported on Friday that it had a solid financial position with nearly $470 million in cash, cash equivalents and marketable securities as of the end of last year, it also revealed a high cash burn rate, driven by an uptick in R&D expenses. These jumped to $56.3 million in the fourth quarter of 2024, compared to $18.4 million the same time a year earlier.Gap in near-term catalystsThe company's pipeline includes vormatrigine (PRAX-628), currently in trials for focal onset seizures and generalised epilepsy. The Phase II RADIANT study and Phase II/III POWER1 registrational study are expected to produce top-line results in mid-2025 and the second half of 2025, respectively. While showing promise in preclinical studies with "superior selectivity for disease-state NaV channel hyperexcitability," vormatrigine is still years away from potential commercialisation.Relutrigine (PRAX-562), an oral inhibitor of persistent sodium current for developmental and epileptic encephalopathies (DEEs), received its third Rare Pediatric Disease Designation from the FDA in December, this time for Dravet syndrome. The compound is currently in the mid-stage EMBOLD study for SCN2A and SCN8A DEEs, with headline results anticipated in the first half of 2026 and a regulatory filing later that year. Praxis plans to start the EMERALD study for DEEs by mid-2025.Finally, elsunersen (PRAX-222), an antisense oligonucleotide designed to decrease SCN2A gene expression, is being developed for early-seizure-onset SCN2A-DEE, and advancing with a finalised registrational trial design. The Phase III EMBRAVE3 study is expected to begin enrolling patients by mid-year.On a more positive note, Praxis said UCB exercised its option to in-license global rights for an KCNT1 small-molecule development candidate. This brings Praxis an option exercise fee and potential milestone payments totalling approximately $100 million, plus tiered royalties on net sales.