ABSTRACT
rVIII-SingleChain is indicated for treatment and prophylaxis of bleeding in patients with haemophilia A (HA). The safety and efficacy of rVIII-SingleChain have previously been shown in the AFFINITY clinical trial programme. This survey evaluated clinical experience following a switch to rVIII-SingleChain from the perspective of both physicians and patients. A web-based survey (July-September 2019) involving 14 Haemophilia Treatment Centres (HTCs) collected data about HA patients who were under treatment with rVIII-SingleChain for ≥ 12 months, as reported by their physicians. In addition, about half of these patients were separately interviewed. Out of 91 patients receiving rVIII-SingleChain in the 14 participating HTCs, 48 had been treated for ≥ 12 months; among those 48, 38% were ≤ 18 years, 37% 19-40 years and 25 % ≥ 41 years; 73% of them had severe HA and 85% were being treated with prophylactic therapy. Twenty-six patients accepted to be separately interviewed: mean age was 30 years; 62% had severe HA and 85% were receiving prophylaxis. Focusing on those patients who were already in prophylaxis with prior FVIII (all but one with recombinant factors), infusion frequency was significantly reduced from 3-2 per week following the switch to rVIII-SingleChain (mean, 2.74 vs. 2.44, respectively; p=0.013), as reported by physicians; the rate of patients needing 3 infusions per week dropped from 74% with previous products to 44% with rFVIII-SingleChain. The annual mean factor consumption was 4740 IU/Kg (median, 4500 IU/Kg; min, 2.215 IU/Kg; max, 7.200 IU/Kg) with prior product and 4320 IU/Kg (median, 4320 IU/Kg; min, 2.215 IU/Kg; max, 6.646 IU/Kg) with rVIII-SingleChain. Both physicians and patients reported a significant reduction in annual total bleeding rates with rVIII-SingleChain compared with prior product (mean 2.15-0.96 and 2.46-0.71 events/year, p = 0.031 and p = 0.018, respectively). Mean satisfaction ratings (from 1; dissatisfied, to 5; very satisfied) for rVIII-SingleChain were quite high for both physicians (4.14, 86% satisfied/very satisfied) and patients (4.18, 86% satisfied/very satisfied). This survey suggested that switching to rVIII-SingleChain allowed patients to reduce their injection frequency without increasing factor consumption or compromising clinical results. Both physicians and patients reported a positive experience with rVIII-SingleChain after 1 year of treatment.
Subject(s)
Factor VIII , Hemophilia A , Hemorrhage , Adult , Factor VIII/therapeutic use , Hemophilia A/drug therapy , Hemorrhage/drug therapy , Hemorrhage/prevention & control , Humans , Italy , Physicians , Surveys and QuestionnairesABSTRACT
Rigorous evidence is lacking on long-term outcomes of factor VIII (FVIII) prophylaxis initiated in adolescent or adult patients with severe haemophilia A. The prospective, open-label Prophylaxis versus On-demand Therapy Through Economic Report (POTTER) study (ClinicalTrials.gov NCT01159587) compared long-term late secondary prophylaxis (recombinant FVIII-FS 20-30 IU/kg thrice weekly) with on-demand treatment in patients aged 12 to 55 years with severe haemophilia A. The annual number of joint bleeding episodes (primary endpoint), total bleeding episodes, orthopaedic and radiologic (Pettersson) scores, health-related quality of life (HRQoL), pharmacoeconomic impact, and safety were evaluated over a > 5-year period (2004-2010). Fifty-eight patients were enrolled at 11 centres in Italy; 53 (27 prophylaxis, 26 on demand) were evaluated and stratified into 2 age subgroups (12-25 and 26-55 years). Patients receiving prophylaxis experienced a significantly lower number of joint bleeding episodes vs the on-demand group (annualised bleeding rate, 1.97 vs 16.80 and 2.46 vs 16.71 in younger and older patients, respectively; p=0.0043). Results were similar for total bleeding episodes. Prophylaxis was associated with significantly fewer target joints (p< 0.001), better orthopaedic (p=0.0019) and Pettersson (p=0.0177) scores, better HRQoL, and fewer days of everyday activities lost (p< 0.0001) but required significantly higher FVIII product consumption. The POTTER study is the first prospective, controlled trial documenting long-term benefits of late secondary prophylaxis in adolescents and adults with severe haemophilia A. The benefits of reduced bleeding frequency, improved joint status, and HRQoL may offset the higher FVIII consumption and costs.
