Baxter International has begun dosing the first patients in a Phase I clinical trial of investigational candidate BAX 855, a longer-acting (PEGylated) form of a full-length recombinant factor VIII (rFVIII) protein.

The prospective open-label Phase I trial is intended to evaluate the safety, tolerability and pharmacokinetics of BAX 855 in previously-treated patients aged 12 years or older with severe haemophilia A.

BAX 855 relies on the company’s Antihemophilic Factor (Recombinant) Plasma/Albumin-Free Method (ADVATE) full-length rFVIII molecule and plasma/albumin-free manufacturing process, which does not contain any human or animal-derived additives.

Baxter BioScience business global research and development vice-president Hartmut Ehrlich said that the Phase I results will form the basis of advancing the programme through clinical development, and will determine whether BAX 855 can offer a treatment regimen requiring fewer infusions than ADVATE.

"This trial is designed to provide new insights about our investigational longer-acting FVIII molecule, BAX 855, with the ultimate goal of improving care for patients living with haemophilia A," Ehrlich said.

BAX 855 uses Nektar Therapeutics’ proprietary PEGylation technology, which is designed to extend the duration of activity of proteins and larger molecules.

ADVATE is a recombinant FVIII therapy that is processed without any blood-based additives. It is approved in 53 countries, including the US, Canada, Argentina, Australia, Brazil, Chile, Colombia, Japan, Malaysia, Singapore, South Korea, Suriname, Switzerland, Taiwan, Uruguay, Venezuela and 27 EU member states.

The Phase IV prophylaxis study sponsored by Baxter showed that using ADVATE for routine prophylaxis considerably reduced median annual bleed rates in haemophilia A patients.