Despite being one of the most common movement disorders, public recognition of ET and its impact remain low. Furthermore, up to 50% of patients do not respond to propranolol, the only FDA indicated medication for ET, prompting the need for more effective and better tolerated therapies. Ulixacaltamide, a novel, selective T-type calcium channel blocker specifically designed for ET patients, showed meaningful improvement in TETRAS Activities of Daily Living (ADL) measures in Essential1 (NCT05021991) alongside a well-tolerated safety profile. Here we assess the effect of ulixacaltamide treatment in patients receiving propranolol. 

133 adults with moderate-to-severe ET were enrolled in Essential1, an 8-week, double-blind, placebo-controlled study with optional Extension. Participants were randomized to ulixacaltamide QAM or placebo followed by blinded lead-in (DBLI; through week 14) during which all participants were titrated to ulixacaltamide. Change in mADL11 (TETRAS-ADL items 1-11 with modified score) for ulixacaltamide compared to placebo was assessed in a subset of participants (n=36) on a stable propranolol dose throughout the study. Corresponding responder analyses were conducted based on clinically meaningful within-patient change in mADL11 defined as a minimum 3-point improvement.