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Introduction In haemophilia, prophylactic infusion of replacement factor can result in improvements in health-related quality of life (HRQoL) when compared with episodic treatment. The Haemophilia-specific Quality of Life (Haem-A-QoL) questionnaire assessed HRQoL in adults with severe haemophilia A or B who received prophylactic or episodic treatment with recombinant factor VIII or IX Fc fusion protein (rFVIIIFc or rFIXFc) in the A-LONG or B-LONG clinical studies. Aims Understand changes in HRQoL during the A-LONG and B-LONG trials. Methods Group-level and individual-level changes over time for the Haem-A-QoL key domains of ‘Physical Health’ and ‘Sports & Leisure,’ and ‘Total Score’ were evaluated in adults through baseline and 6-month HRQoL assessments. Previously determined responder definitions (RDs) were used for evaluating meaningful subject-level HRQoL improvements. Results The analysis included 67 A-LONG and 51 B-LONG subjects who completed the Haem-A-QoL (baseline and 6 months). While HRQoL improvements were observed among all treatment groups, greater improvements in HRQoL were observed among subjects who received episodic treatment pre-study (and prophylaxis on-study) compared to those who received hyphenate prophylaxis. Applying the RDs for interpreting 6-month changes, 47.4%/33.3% (‘Physical Health’), 35.9%/50.0% (‘Sports & Leisure’) and 23.9%/33.3% (‘Total Score’) of A-LONG subjects who received individualized or weekly prophylaxis were classified as HRQoL responders. In B-LONG, 69.2%/57.9% (‘Physical Health’), 44.4%/56.7% (‘Sports & Leisure’) and 41.7%/44.1% (‘Total Score’) of subjects who received individualized or weekly prophylaxis were classified as HRQoL responders. Conclusion Changes in Haem-A-QoL key domains and ‘Total Score’ suggest that prophylaxis with long-acting rFVIIIFc or rFIXFc resulted in meaningful HRQoL improvements.

The Haemophilia Quality of Life Questionnaire for Adults (Haem-A-QoL) measures health-related quality of life (HRQoL) in adults with haemophilia; however, change score thresholds for identifying individuals experiencing a HRQoL benefit have not been appropriately investigated. The objective of this analysis was to derive appropriate HRQoL responder definitions (RDs) for two Haem-A-QoL domains that reflect key impairments, 'Physical Health' and 'Sports & Leisure,' and the Haem-A-QoL 'Total Score' using anchor- and distribution-based methods. In this analysis, data from adults in A-LONG and B-LONG, two Phase 3 clinical studies of rFVIIIFc in haemophilia A and rFIXFc in haemophilia B, respectively, were used. The anchor-based approach identified Haem-A-QoL changes corresponding to EQ-5D item improvements between baseline and 6 months; the distribution-based methods examined the magnitude at baseline of one-half standard deviation and the standard error of measurement. Through triangulation, the most appropriate RDs were derived. Of the 133 A-LONG and 73 B-LONG subjects with baseline Haem-A-QoL scores, 67 and 51 subjects, respectively, completed the Haem-A-QoL questionnaire at both baseline and 6 months follow-up. Triangulation of anchor- and distribution-based estimates with the observed Haem-A-QoL change scores identified a 10-point reduction in the 'Physical Health' and 'Sports & Leisure' domains, and a 7-point reduction in 'Total Score' as the RD thresholds most indicative of HRQoL benefit. These empirically derived RDs for two key Haem-A-QoL domains and 'Total Score' are reasonable and practical thresholds for identifying subjects with notable improvements in HRQoL, and provides HRQoL RDs that can be used for further analysis and interpretation of data from haemophilia clinical trials.