Merrimack Begins Study of Drug for Treating Uveitis

Merrimack Pharmaceuticals has initiated a Phase II pilot study to determine the safety and efficacy of its immunomodulator MM-093 in patients suffering from autoimmune uveitis. MM-093, Merrimack's lead product, is a recombinant version of human alpha-fetoprotein.

Uveitis is an autoimmune inflammatory disease that produces eye pain, light sensitivity and diminished vision, including blindness. Sarcoid and birdshot are rare uveitis subtypes, which could be classified as orphan indications due to their small patient size, according to the company.

The randomized, double-blind, placebo-controlled study will examine the safety and efficacy of MM-093 in approximately 20 patients with either sarcoid or birdshot uveitis. Patients will discontinue their current therapies for uveitis and be treated with MM-093 or placebo for up to 36 weeks. This study is a flare design, where the number of patients whose uveitis relapses after discontinuing the use of their background therapies will be assessed at the end of the study. Patients who experience a flare of uveitis during the study will be retreated with their original therapies.

"Uveitis remains a significant cause of blindness in developed countries, and immunosuppressive chemotherapy and systemic corticosteroid therapy continue to form the backbone for ocular immunologists trying to preserve the vision of patients who are going blind from uveitis. However, such therapies can cause significant, potentially serious side effects," Stephen Foster, principal investigator for the study, said. "MM-093 is a particularly promising immunomodulatory molecule from a risk/benefit standpoint, with very little likelihood of exposing patients to the side effects of corticosteroid or of immunosuppressive therapy."