Baxter International Inc. (NYSE:BAX) today announced that the U.S. Food and Drug Administration (FDA) has approved GAMMAGARD LIQUID 10% [Immune Globulin Infusion (Human)] as a treatment for multifocal motor neuropathy (MMN). This is the first immunoglobulin treatment approved for MMN patients in the United States, and it was approved for use with MMN patients in Europe in 2011.
MMN is associated with a progressive, asymmetric limb weakness mostly affecting the upper limbs, which can lead to significant difficulty with simple manual tasks. Nearly 80 percent of people with MMN are between 20 and 50 years of age at onset of the disease, and men are more frequently affected than women. Baxter has been granted Orphan Drug Designation for this indication in the United States, as the prevalence of MMN is estimated at between one or two people for approximately 100,000 individuals.
''Multifocal motor neuropathy, known as MMN, is a challenging neuromuscular disease to diagnose and manage, and patients have had limited treatment options. With the introduction of GAMMAGARD LIQUID as an FDA approved treatment option, we're able to offer patients a proven therapy to help them improve their function in their hands and feet,'' said Said R. Beydoun, M.D., FAAN, professor of neurology at the Keck Medical Center of USC, University of Southern California and investigator on the MMN clinical trial.
''The regulatory approval of GAMMAGARD LIQUID for the treatment of MMN is an important milestone for Baxter as we continue to build our presence in the immunoglobulin market and expand into rare diseases in neurology. With GAMMAGARD, we can offer patients with MMN a therapeutic option that has been well studied and used with primary immunodeficiency patients for many years,'' said Ludwig Hantson, Ph.D., president of Baxter's BioScience business.
The approval was based on the results of a randomized, double-blind, placebo controlled, cross-over study conducted to evaluate the efficacy and safety/tolerability of GAMMAGARD LIQUID in 44 adult subjects with MMN. The pivotal clinical study results were presented during the American Academy of Neurology annual meeting in April 2012. The two co-primary endpoints were grip strength in the more affected hand and disability, as measured by Guy's Neurological Disability Scale (which measures the patient's ability to perform daily tasks such as zippering, buttoning, tying shoe laces, washing and feeding).
During GAMMAGARD LIQUID treatment, the difference in relative change in mean grip strength in the more affected hand was 22.94% compared to placebo. A greater proportion of patients who received placebo experienced deterioration compared to those receiving GAMMAGARD LIQUID (35.7% vs.11.9%, respectively). The differences in the outcomes of the co-primary endpoints were statistically significant. In addition, the majority of patients (69%) required an accelerated switch to GAMMAGARD LIQUID due to functional deterioration during the placebo period.
The most common adverse reactions (observed in ≥5% of subjects) during infusion with GAMMAGARD LIQUID were headache, chest discomfort, muscle spasms, muscular weakness, nausea, oropharyngeal pain, and pain in extremity. The serious adverse reactions were pulmonary embolism and blurred vision which were judged to be treatment-related. No deaths or unexpected serious adverse events related to study product occurred.