The landscape for hemophilia treatment options has greatly evolved in the last few years. Most recently is the addition of gene therapy for the treatment of bleeding disorders. {Gene therapy adds a new gene or replaces or repairs a mutated gene in a cell to prevent or treat a disease}

A bleeding disorder gene therapy lexicon is currently being developed by various industry stakeholders, and the need for an objective, unbiased lexicon is vital for dissemination of the complexities of gene therapy to patients, caregivers, and healthcare providers.    


MASAC recognizes the need for a harmonized terminology for healthcare providers, patients, and caregivers to use in discussions surrounding gene therapy. 


MASAC recommends the development of a bleeding disorder gene therapy lexicon to serve as the agreed upon terminology. MASAC recommends that the lexicon be developed by a collaborative effort among professional organizations and representatives from the bleeding disorder community (i.e. Lived Experience Experts – [LEEs]). MASAC recommends/encourages multiple professional organizations to contribute to this effort. To that end, MASAC is willing and available to collaborate and serve in the lexicon development process.











This material is provided for your general information only. NBDF does not give medical advice or engage in the practice of medicine. NBDF under no circumstances recommends particular treatment for specific individuals and in all cases recommends that you consult your physician or local treatment center before pursuing any course of treatment.


Copyright 2024 National Bleeding Disorders Foundation. To facilitate the dissemination of these medical recommendations, reproduction of any material in this publication in whole or in part will be permitted provided: 1) a specific reference to the MASAC recommendation number and title is included and 2) the reproduction is not intended for use in connection with the marketing, sale or promotion of any product or service. NBDF reserves the right to make the final determination of compliance with this policy. For questions or to obtain a copy of the most recent recommendations, please contact the NBDF Senior Vice President for Programs and Medical Information at or visit the NBDF website at