High-titre inhibitors in previously untreated patients with severe haemophilia A receiving recombinant or plasma-derived factor VIII: a budget-impact analysis

Emicizumab for the treatment of haemophilia A: a narrative review

One of the most serious complications of the treatment of severe haemophilia A is the development of alloantibodies against exogenous factor VIII (FVIII). Inhibitors render factor replacement therapy ineffective, exposing patients to a remarkably high risk of morbidity and mortality. Besides the well-known bypassing agents (i.e. activated prothrombin complex concentrate and recombinant activated factor VII) used to treat or prevent bleeding in haemophilia patients with inhibitors, there is growing interest in newer haemostatic therapies that are not based on the replacement of the deficient FVIII. This review will focus on the most interesting among these innovative therapies, emicizumab, and will provide an update on its current stage of clinical development.

Factors affecting the quality, safety and marketing approval of clotting factor concentrates for haemophilia

Selecting therapeutic products for the treatment of haemophilia follows the process of obtaining market approval of products submitted to the scrutiny of a regulatory agency. In well-resourced countries, key decisions on whether a product is sufficiently safe and of high quality are made by highly expert and well-resourced agencies, such as the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). In countries lacking such agencies, well-informed decisions can still be made through an appreciation of the key issues affecting the quality, safety and efficacy of haemophilia products. A number of well-established principles may then be applied in order to make a choice. In this review, reflecting principles outlined by the World Federation of Hemophilia, we outline the key features in determining the acceptability of therapeutic products for haemophilia in order to ensure an optimal choice in all the environments providing haemophilia care.

A contemporary look at FVIII inhibitor development: still a great influence on the evolution of hemophilia therapies

INTRODUCTION

The development of inhibitors against factor VIII (FVIII) replacement therapy remains the most important challenge for clinicians in the treatment of hemophilia patients. This review focusses on risk factors and management of FVIII inhibitors, particularly in light of SIPPET study findings and subsequent analyses. Areas covered: A brief history and evolution of hemophilia therapies is provided, including an overview of conventional and new (including investigational) therapeutic approaches for the treatment of hemophilia. The SIPPET study, the first randomized clinical trial to demonstrate a lower incidence of inhibitors in previously untreated patients treated with plasma-derived FVIII products compared with recombinant FVIII products, has generated much debate. We review the SIPPET trial and reactions, in addition to preliminary observations from a single center's experience, the cost impact of inhibitors, recent findings from SIPPET subanalyses, and inhibitor development in previously-treated patients. Expert commentary: Despite recent advances in potential new treatment options for hemophilia, conventional factor replacement concentrates currently remain the cornerstone of treatment. It is paramount that clinicians familiarize themselves with the findings from the SIPPET trial and substudies, in order to better inform their patients and families on inhibitor risk factors and to aid the treatment decision-making process.