ABSTRACT
Introduction: Replacement therapy for FVIII/IX in hemophilia A/B is more than 50 years old following the discovery of cryoprecipitate by Judith Pool in 1964. On-demand therapy and prophylaxis to treat or prevent bleedings is very demanding owing to the short half-life (HL) of factor concentrates (no more than 12–14 h for FVIII or 16–18 h for FIX). Patients are very eager to prolong the intervals between bolus. The enhanced HL of long-acting recombinant FIX (rFIX) concentrates seems to fulfill this expectance.
Areas covered: Great improvements have been achieved in the bio-engineering of new rFIX concentrates. Production, formulation, pharmacokinetics, pharmacodynamics, efficacy and tolerability of albutrepenonacog alfa (rIX-FP, trade name Idelvion) will be addressed. rIX-FP is produced by expression of genetically linked FIX and albumin in Chinese Hamster Ovary cells. rIX-FP exhibits a long HL, low clearance and small volume of distribution.
Expert opinion: There is no doubt that rIX-FP, as well as other long-acting rFIX concentrates, will facilitate and improve the adherence to therapy of younger hemophilia patients, toddlers and children. Efficacy, safety and immunogenicity of rIX-FP must be assessed not only during the regulatory clinical trials but also by post-marketing surveillance.
Declaration of interest
M Morfini acted as paid consultant to Baxter, Novo Nordisk, Pfizer and received a fee as invited speaker at CSL Behring, Kedrion, Novo Nordisk and Octapharma Symposia. The author has no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.