Cathie Wood Just Bet Big on This Biotech Stock

Cathie Wood’s ARK Genomic Revolution ETF (ARKG) has increased exposure to Ionis Pharmaceuticals, buying $15.3 million worth of Ionis shares since the beginning of July. The move comes as Ionis stock is down nearly 37% from its 2026 peak earlier this month, following a late-stage trial setback involving its partner AstraZeneca. The companies announced failure for eplontersen, a treatment for transthyretin amyloidosis cardiomyopathy (ATTR-CM), a rare heart disease. The purchases were made after the announcement, suggesting Wood is weighing the decline against a long-term thesis. Separately, Ionis gained FDA approval in June 2026 for its drug Tryngolza (olezarsen) for severe hypertriglyceridemia (sHTG), expanding a previously narrower indication from 2024. Trial results showed triglyceride reductions of up to 72% and reduced acute pancreatitis events by 85% to 91%.