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Efficacy & Safety

Confidence in demonstrated safety, regardless of age or treatment regimen1,2,3

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No inhibitors developed in pediatric or adult patients in any of the completed LEOPOLD trials, which consisted of 193 PTPs


The incidence of drug-related adverse events was low in each trial:

  • 6.5% in LEOPOLD I Part B1
  • 4.0% in LEOPOLD II2
  • 2.0% in LEOPOLD Kids Part A3

LEOPOLD, Long-Term Efficacy Open-Label Program in Severe Hemophilia A Disease; PTP, previously treated patient


  • Saxena K, Lalezari S, Oldenburg J, et al. Efficacy and safety of BAY 81-8973, a full-length recombinant factor VIII: results from the LEOPOLD I trial. Haemophilia. 2016;22(5): 706-712. Return to content
  • Kavakli K, Yang R, Rusen L, et al. Prophylaxis vs. on-demand treatment with BAY 81-8973, a full-length plasma protein-free recombinant factor VIII product: results from a randomized trial (LEOPOLD II). J Thromb Haemost. 2015;13(3):360-36. Return to content
  • Ljung R, Kenet G, Mancuso M, et al. BAY 81-8973 safety and efficacy for prophylaxis and treatment of bleeds in previously treated children with severe haemophilia A: results of the LEOPOLD Kids Trial Haemophilia. 2016;22(3):354-60. Return to content