Biogen and Swedish Orphan Biovitrum (Sobi) will jointly release data of the Phase III clinical extension studies, B-YOND and ASPIRE of Elocta and Alprolix, to treat haemophilia A and haemophilia B respectively.

Elocta (efmoroctocog alfa) is a recombinant clotting factor VIII therapy acting over a prolonged period in the body, while alprolix (eftrenonacog alfa) is also a recombinant clotting factor therapy indicated to be used for haemophilia B.

Haemophilia is a rarely occurring genetic disorder characterised by the inability to repair blood clot.

Patients afflicted with haemophilia A or B experience prolonged bleeding episodes causing pain, irreversible joint damage and life-threatening hemorrhages.

"Elocta and Alprolix are backed by robust clinical data and significant real-world experience."

Elocta treats haemophilia A by binding factor VIII to the Fc portion of protein immunoglobulin G subclass 1, or IgG1.

It creates a natural pathway able to be used by Elocta for a prolonged operation in the body.

Alprolix treats haemophilia B by binding factor IX to the Fc portion of immunoglobulin G subclass 1, or IgG1 which creates a natural pathway to be used by Alprolix for an extended action within the body.

A post-hoc analysis of the studies intends to present a longitudinal evaluation of joint health from patients participating in A-LONG and ASPIRE studies, while target joint data gathered from the subset of patients involved in the B-LONG and B-YOND studies will also be presented at the WFH Congress.

Sobi haemophilia medical therapeutic area head and vice-president Krassimir Mitchev said: “Elocta and Alprolix are backed by robust clinical data and significant real-world experience.

“We believe these new data presentations will help healthcare providers to deepen their understanding of the clinical value and utility of these innovative medicines.”

The companies will also present preclinical pharmacokinetic data of recombinant FVIIIFc-VWF-XTEN, a fusion protein using XTEN technology to treat haemophilia A.