Alnylam Pharmaceuticals reported that their RNA interference drug zilebesiran did not achieve a statistically significant blood pressure reduction in a key Phase 2 trial involving patients with moderately high triglycerides. Despite a modest reduction of 5 mmHg compared to placebo, efficacy endpoints were unmet, raising questions about the treatment’s potential benefit as it progresses to late-stage cardiovascular outcomes trials. Higher dosing did not yield additional advantage.