ARK Invest owns shares of Alpha Tau Medical Ltd. (DRTS), a biotechnology company specializing in alpha-radiation cancer treatments. Instead of holding it in their main genomics fund (ARKG), ARK primarily holds DRTS through their ARK Israel Innovative Technology ETF (IZRL).
Recent Investment ActivityInitial Stake: Cathie Wood first initiated a position in DRTS in January 2026, purchasing roughly $2 million worth of shares.ETF Weight: Within the ARK IZRL ETF, Alpha Tau Medical (DRTS) has risen to become the #1 largest individual holding, representing approximately 2.05% of the total fund.
Institutional Trend: Regulatory 13F filings from Q1 2026 confirmed that DRTS is one of the distinct new stock positions officially added to ARK Investment Management’s wider multi-fund portfolio.
Market Performance CatalystThe stock experienced a major 20% pre-market surge following a significant clinical breakthrough:
Trial Results: Alpha Tau reported highly encouraging interim data from its recurrent glioblastoma (brain cancer) trials.Efficacy: Out of the first three patients treated with their experimental Alpha DaRT therapy, two achieved a complete response (no remaining signs of cancer) and the third patient saw a 30% tumor reduction.
Regulatory Milestones: This follows their first international marketing clearance in Japan and a rolling FDA pre-market application in the United States.
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