Use of the Functional Assessment of Cancer Therapy-Anemia (FACT-An) Instrument in Persons with MPN-Associated Myelofibrosis and Anemia

Myeloproliferative neoplasm (MPN)-associated myelofibrosis is characterized by anemia in almost all affected persons. The Functional Assessment of Cancer Therapy (FACT) measurement system is a patient-reported outcome (PRO) developed to document symptoms to diverse aspects of cancer treatment. One FACT version, FACT-An, specifically addresses symptoms of anemia related to cancer- therapy. FACT-An has been validated in diverse cancer populations but not in MPN-associated myelofibrosis.

Data were from a phase-2 randomized double-blind Bayesian “pick-the-winner” trial of pomalidomide and prednisone in subjects with MPN-associated myelofibrosis and anemia (including RBC-transfusion-dependence). Details of the study, including definitions of anemia, response, RBC-transfusion-dependence and –independence were published previously. Change in quality of life (QOL) from randomization to the last cycle of therapy was evaluated by using the FACT-An physical well-being (PWB), functional well-being (FWB), trial outcome index (TOI) and anemia (An) domains. Minimally clinically important differences (MID) were used to determine the smallest difference in scores which subjects perceived as beneficial in the FACT-An domains of interest. Subjects were classified as meeting MID for responsiveness if their change score from baseline was greater than one standard error of measurement (SEM), indicating improvement.

85 subjects were studied. All FACT-An domains showed strong reliability as measured by Cronbach's alpha. 31 were classified as anemia responders by clinical and laboratory criteria. Anemia responders showed greater improvement in PWB, FWB and TOI scores than non-responders (TOI presented below) across all FACT-An domains. Improvement began at the 2nd 28 d cycle of therapy and was sustained.

We show anemia response defined by IWG-MRT criteria correlates with improved QOL measured by the FACT-An instrument in persons with MPN-associated myelofibrosis.

Tencer:Celgene Corporation: Employment. Gale:Celgene Corporation: Employment. Khan:Celgene: Employment.