Atavistik Bio extended its Series B financing by $40 million, bringing total Series B proceeds to $160 million to support clinical trials of allosteric therapies for hereditary hemorrhagic telangiectasia (HHT) and other blood disorders. Investors view the financing as validation for precision modulation of blood‑related targets where no approved therapies exist. Atavistik’s lead programs target rare vascular and hematologic diseases; the company said funds will accelerate an HHT clinical study and support pipeline advancement toward the clinic. The round signals sustained investor appetite for specialty hematology programs with clear genetic or pathway biology. Allosteric modulators offer tunable activity at protein targets and can provide differentiated safety or pharmacology versus orthosteric inhibitors—an attractive profile for chronic vascular disorders.