ATX-011

ATX-011 is Alethio Therapeutics’ preclinical, first-in-class, mutation-agnostic monoclonal antibody for chronic-phase myeloproliferative neoplasms, principally **essential thrombocythemia**. It binds a novel, undisclosed surface antigen reported to be selectively overexpressed on the mutant myeloproliferative-neoplasm clone. Alethio states that the program is designed to reduce platelet counts and thrombotic risk while targeting disease-driving mutant stem and progenitor cells, with non-human-primate studies showing rapid, controlled, reversible platelet reduction and favorable tolerability. The program was disclosed in April 2026 and was expected to enter IND-enabling development ahead of a planned IND submission in the first quarter of 2027. ([alethiotherapeutics.com](https://alethiotherapeutics.com/alethio-therapeutics-unveils-atx-011-a-breakthrough-mutation-agnostic-antibody-for-treating-essential-thrombocythemia-a-c-2b-market/))