Introduction: Damoctocog alfa pegol (BAY 94-9027) is an extended half-life PEGylated recombinant
factor VIII (FVIII) product approved for treatment of haemophilia A in previously
treated patients (PTPs) aged≥12 years. Longitudinal assessment of its real-world effectiveness
and safety is ongoing in the HEM-POWR study (NCT03932201). HEM-POWR is a phase IV,
open-label, prospective cohort study including PTPs with severe and non-severe haemophilia
A receiving damoctocog alfa pegol prophylactically or on demand. Here, we present
results from the fifth interim analysis of PTPs from German study sites.
Method: The primary endpoint was annualised bleeding rate (ABR); secondary endpoints included
safety. Exploratory and descriptive analyses were performed using data captured from
patient diaries and physician records. PTPs who had a first documented dose of damoctocog
alfa pegol in the study plus≥1 documented infusion during the observation period were
included in the full analysis (FAS); the safety analysis (SAF) included PTPs with≥1
study dose during the observation period. Ethical approval and informed consent were
obtained for all sites and patients, respectively.
Results: At data cut-off (8 July 2024), 54 and 73 PTPs were included in the FAS and SAF from
German study sites, respectively. The median (Q1, Q3) observation period in the FAS
was 1096.0 (938.0, 1171.0) days. The majority of patients in the FAS were aged≥18
to<65 years (45/54, 83.3%) and had severe disease (44/54, 81.5%) ([Fig. 2]). The most common dosing regimen was every 2 days (24/54; 44.4%) with prior FVIII
product and at baseline with damoctocog alfa pegol (17/54; 31.5%), and twice weekly
dosing at 6- (20/53; 37.7%) and 12-month follow-up (19/50; 38.0%). Median (Q1, Q3)/mean
(SD) ABR for total bleeds with prior FVIII treatment was 1.0 (0.0, 2.0)/2.1 (3.4)
and during the observation period with damoctocog alfa pegol was 0.3 (0.0, 0.9)/1.0
(1.9) ([Fig. 1]). The difference in ABR for total bleeds was 0.0 (–1.5, 0.3)/–1.1 (3.0), for spontaneous
bleeds was 0.0 (–0.9, 0.0)/–0.7 (2.1), for joint bleeds was 0.0 (–1.0, 0.0)/–0.8 (2.6),
and for spontaneous joint bleeds was 0.0 (0.0, 0.0)/–0.6 (1.7). In the SAF, 32/73
(43.8%) patients reported treatment-emergent adverse events (TEAEs); 11 (15.1%) were
serious. TEAEs led to a change in treatment regimen in 12 (16.4%) patients. There
were 2 (2.7%) TEAEs of special interest, 2 (2.7%) study drug-related TEAEs, 1 transient
inhibitor that resolved, and 1 death due to spinal cord ischaemia, which was unrelated
to the study drug.
Fig. 2 Baseline demographics and clinical characteristics of patients in the FAS and SAF*Data
missing for 15 patients. †Data missing for 24 patients. ‡Data missing for 21 patients. §Data missing for 2 patients. FAS, full analysis set; FVIII, factor VIII; IU, international
units; Q1, 1st quartile; Q3, 3rd quartile; SAF, safety analysis set.
Fig. 1 Mean (SD) ABR with previous FVIII product in the 12 months prior to damoctocog alfa
pegol in*Data missing for 1 patient. ABR, annualised bleeding rate; FAS, full analysis
set; FVIII, factor VIII; SD, standard deviation.
Conclusion: Damoctocog alfa pegol demonstrated efficacy and a favourable safety profile in real-world
treatment of patients with haemophilia A, consistent with previous German subpopulation
analyses of HEM-POWR. These analyses provide valuable and tailored clinical practice
insights and stakeholder information.
Funded by Bayer.
Acknowledgments: Editorial support was provided by Amy Miles and Natalie Mitchell of Avalere Health
Global Limited, and was funded by Bayer. This study was funded by Bayer.
