The Food and Drug Administration has approved Hizentra as the first subcutaneously administered human immunoglobulin maintenance therapy for adults with chronic inflammatory demyelinating polyneuropathy (CIDP), according to a statement from its manufacturer, CSL Behring.
Immune globulin subcutaneous (human) 20% liquid (Hizentra) was approved at doses of 0.2 and 0.4 g/kg per week because of the strength of the phase 3 PATH (Polyneuropathy and Treatment with Hizentra) clinical trial and the PATH extension study, which is still ongoing. PATH is the largest and longest running randomized study of patients with CIDP. The clinical trial studied the safety, efficacy, and tolerability of the two different doses of the subcutaneous immunoglobulin in 172 patients.
CIDP is a rare autoimmune disease that affects the peripheral nerves and can cause permanent damage by degrading the myelin sheath, the fatty sheath along many nerve fibers. This can eventually lead to changes in activity levels and a decrease in the quality of life. Approximately 30% of patients with CIDP patients will require a wheelchair at some point in their lives if they do not receive treatment, the manufacturer said in its announcement .
There were markedly lower rates of CIDP relapse or withdrawal for any reason during Hizentra treatment among patients taking a high dose of 0.4 g/kg weekly (39%; P less than .001) and those taking a low dose of 0.2 g/kg weekly (33%; P less than .007), compared with those among patients taking placebo (63%). The adverse reactions that occurred in 5% or more of patients included local infusion-site reactions, headache, diarrhea, fatigue, and upper respiratory tract infections.
The European Commission also recently granted marketing authorization for Hizentra based on the information from the PATH trial.
Hizentra was initially approved in the United States in 2010 for primary immunodeficiency in patients aged 2 years and older.
Since Hizentra is a self-administered drug, it is important for physicians to teach their patients how to properly inject this treatment without hitting a blood vessel. Apart from issues related to self-administration, the risk of thrombosis is also present, which is not uncommon for immune globulin products.