Tessera Therapeutics confirmed it will commence the first human trial of its in vivo gene writing platform next month, testing the approach in adults with a rare genetic disease (alpha‑related indication). The study is the earliest clinic test of 'gene writing' — in situ genomic sequence change without double‑strand breaks — and represents a step beyond classical gene editing and gene addition. Tessera’s entry to the clinic will provide the first human safety and activity readouts for the platform, and the outcome will influence investor and scientific confidence in gene‑writing modalities as a distinct path to durable genetic medicines.