Health-related quality of life and physical activity in Nordic patients with moderate haemophilia A and B (the MoHem study)

INTRODUCTION

The impact of moderate haemophilia on health-related quality of life (HRQoL) and physical activity (PA) is not well known. In previous studies, persons with factor VIII/factor IX activity (FVIII/FIX:C) below 3 IU/dL were associated with a more severe bleeding phenotype than predicted.

AIM

To explore HRQoL and PA in patients with moderate haemophilia A (MHA) and B (MHB).

METHODS

A cross-sectional, multicentre study covering patients with MHA and MHB in Sweden, Finland, and Norway. HRQoL was assessed with the EuroQoL 5-Dimensions (EQ-5D) form and PA with the International Physical Activity Questionnaire among participants aged ≥15 years.

RESULTS

We report on 104 patients aged 15-84 years from the MoHem study. Overall, EQ-5D utility was .85 (median) (Q1-Q3 0.73-1.0) with corresponding visual analogue scale (VAS) 80 (70-90), which were similar regardless of treatment modality, FVIII/FIX:C, and MHA or MHB. Pain and mobility were most frequently affected dimensions. Utility (r = -.54), VAS (r = -.42), and PA (r = -.32) correlated negatively with arthropathy (HJHS). Only patients aged 41-50 years displayed lower utility (p = .02) and VAS (p < .01) than the Norwegian population norm. Patients on prophylaxis aged 35-54 years reported higher PA than those treated on-demand (p = .01).

CONCLUSION

Haemophilic arthropathy had negative impact on HRQoL and PA in Nordic patients with moderate haemophilia. Middle-aged patients captured lower utility and VAS than observed in the general population. Tailored prophylaxis and improved joint health may influence positively on HRQoL and PA also in moderate haemophilia.

Report on 4 cases with decreased recovery due to neutralizing antibodies specific for PEGylated recombinant factor VIII

BACKGROUND

The immunogenicity, safety, and efficacy of recombinant factor VIII (rFVIII) have gained increasing interest after the introduction of extended half-life products with various modifications of the rFVIII molecule, such as covalent attachment of polyethylene glycol (PEG). Anti-PEG antibodies may be associated with a temporary reduction of FVIII recovery, but according to previous studies, they usually disappear after continuous dosing. Anti-PEG antibodies with an inhibitory capacity have never been demonstrated in patients treated with PEGylated rFVIII products.

OBJECTIVES

To routinely switch from standard half-life to PEGylated extended half-life rFVIII products in patients with hemophilia A.

METHODS

From December 2022 until May 2023, 83 adults with hemophilia A attending Oslo Haemophilia Comprehensive Care Centre received a test dose with a PEGylated rFVIII product to switch treatment. Four patients presented with decreased recovery without the presence of an FVIII inhibitor. Accordingly, we performed a variant inhibitor test utilizing different rFVIII concentrates as a source of FVIII and enzyme-linked immunosorbent assay to search for anti-PEG antibodies.

RESULTS

We found inhibitory anti-PEG/anti-PEGylated rFVIII antibodies in 4 patients (5%), both persistent and transient, explaining the impaired recovery. The patients had neutralizing anti-PEG antibodies prior to the first dosing of PEGylated rFVIII. We demonstrated neutralizing antibodies (mainly immunoglobuline G) specific for PEG and all 3 commercially available PEGylated rFVIII products.

CONCLUSION

The number of patients with inhibitory anti-PEG antibodies was significant, and the presence of inhibitors against PEGylated rFVIII emphasizes the importance of individual monitoring when switching FVIII concentrates to ensure safety and efficacy of the treatment.

Bleeding phenotype of patients with moderate haemophilia A and B assessed by thromboelastometry and thrombin generation

INTRODUCTION

Predicting the bleeding phenotype is crucial for the management of patients with moderate haemophilia. Global coagulation assays evaluate haemostasis more comprehensively than conventional methods.

AIM

To explore global coagulation assays and the bleeding phenotype of patients with moderate haemophilia A (MHA) and B (MHB).

METHODS

The MoHem study is a cross-sectional, multicentre study covering Nordic patients with MHA and MHB. Thromboelastometry in whole blood and thrombin generation (TG) in platelet-poor plasma (1, 2.5 and 5 pM tissue factor (TF)) were compared with joint health (Haemophilia Joint Health Score (HJHS)) and treatment modality.

RESULTS

We report on 61 patients from Oslo and Helsinki: 24 MHA and 37 MHB. By TG (2.5 pM TF), patients who had been without replacement therapy during the previous 12 months depicted higher endogenous thrombin potential (P = .03). In contrast, those who had low ETP (< median) captured higher HJHS (P = .02). Patients who had undergone orthopaedic surgery generated least thrombin (P = .02). By thromboelastometry, those without the need of factor consumption had short clotting times, and quick times to maximum velocity (< median values) (P = .03). Factor VIII/factor IX activity (FVIII/FIX:C) did not align with the bleeding phenotype, but FIX:C ≤ 3 IU/dL was associated with lower peak thrombin (P = .03).

CONCLUSION

TG differentiated patients with moderate haemophilia according to HJHS, annual factor consumption, and whether orthopaedic surgery had been performed. Thromboelastometry differentiated according to factor consumption only. Global coagulation assays may assist predicting the bleeding phenotype in moderate haemophilia.

Haemophilia early arthropathy detection with ultrasound and haemophilia joint health score in the moderate haemophilia (MoHem) study

INTRODUCTION

Detection of early arthropathy is crucial for the management of haemophilia, but data on moderate haemophilia are limited. Therefore, we evaluated joint health and treatment modalities in Nordic patients with moderate haemophilia A (MHA) and B (MHB).

AIM

To explore and compare the Haemophilia Early Arthropathy Detection with Ultrasound (HEAD-US) and Haemophilia Joint Health Score (HJHS) to detect early arthropathy in moderate haemophilia.

METHODS

A cross-sectional, multicentre study covering Nordic patients with MHA and MHB. Arthropathy was evaluated by HEAD-US and HJHS 2.1.

RESULTS

We assessed 693 joints in 118 patients. HEAD-US scores (medians [interquartile ranges]) were as follows: elbows 0 points (0-0), knees 0 (0-0) and ankles 0 (0-1). Respectively, by HJHS: elbows 0 (0-1), knees 0 (0-1) and ankles 0 (0-1). Cartilage (14%) and bone (13%) were most commonly affected by HEAD-US. Frequent HJHS findings were crepitus on motion in knees (39%), and loss of flexion (23%) and extension (13%) in ankles. HEAD-US correlated strongly with HJHS (elbows r = .70, knees r = .60 and ankles r = .65), but 24% had discordant scores. Joints with HJHS zero points, 5% captured HEAD-US ≥1 point. Moreover, 26% had HJHS findings without HEAD-US pathology. Notably, 31% of knees had crepitus on motion and normal HEAD-US.

CONCLUSION

Overall, the joints attained low scores implying good joint health. HEAD-US correlated strongly with HJHS. In 5%, HEAD-US detected subclinical pathology. Crepitus on motion was frequently reported despite normal HEAD-US, thus not necessarily reflecting arthropathy. HEAD-US therefore improves the joint assessment in moderate haemophilia.