Symptoms and life impact of polycythemia vera (PV): Results from a qualitative patient interview study.

e23259 Background: PV is a myeloproliferative neoplasm characterized by excessive red blood cell production. Patients with PV report a substantial symptom burden, including fatigue, pruritus, and concentration problems. To our knowledge, this is the first observational qualitative interview study focused on the PV patient experience. Our objectives were to (a) enhance a literature-informed preliminary PV conceptual disease model of signs, symptoms, and impacts on patients’ lives and (b) assess content validity of patient-reported outcome (PRO) instruments for PV, including the PROMIS Fatigue Short Form (SF)-8a and the Myelofibrosis Symptom Assessment Form (MFSAF) version 4.0. Methods: Adults (≥18 years old) in the USA with a documented PV diagnosis who required ≥3 phlebotomies/year were recruited. Patients participated in 1:1 semi-structured phone interviews (approximately 90 minutes in duration) that were recorded, transcribed, and analyzed using qualitative analysis software (MAXQDA). Interviews began with open-ended exploration of patients’ experience with PV symptoms/impacts (ie, “concept elicitation [CE]”). Salient concepts were defined by frequency (≥6 patients) and mean bother or impact rating (score ≥5 out of 10). Interviews thereafter assessed patients’ understanding of PRO instrument items and their relevance to PV (ie, “cognitive debriefing [CD]”). Results: Twenty patients participated (50% male; mean age, 66.1 years [range, 31-81]; mean time since diagnosis, 5.9 years [range, 1.75-13.25 years]; mean annual phlebotomy rate, 5.3 [range, 3-16]). The majority (55%) received concurrent cytoreductive therapy. CE identified 44 signs/symptoms and 33 impacts. Salient signs/symptoms (n = 15 of 44) included fatigue, itchiness, and low energy; salient impacts (n = 21 of 33) included sleep disturbances, difficulties with self-care or activities of daily living, and work limitations. Using CE data, the preliminary PV conceptual disease model was further refined to include 16 signs/symptoms and 21 impacts in the model. In CD, patients generally found the PROMIS Fatigue SF-8a to be clear, easy to understand, and relevant; this instrument also adequately captured the most salient concept (fatigue). Patients also reported that the MFSAF was generally clear, easy to understand, and largely relevant to their PV experience. Conclusions: The qualitative evidence from these combined CE/CD interviews in 20 patients has produced a more comprehensive understanding of PV, which has been represented in a conceptual model. The evidence also supports the content validity of the PROMIS Fatigue SF-8a and the MFSAF in PV. These findings informed the patient-reported endpoints in the phase 3 VERIFY study (Kuykendall AT et al. J Clin Oncol 2025;43(17_suppl):LBA3) investigating the current standard-of-care plus rusfertide or placebo for treatment of patients with PV who require frequent phlebotomy.