ZymoGenetics and Merck Serono have kicked off a Phase II/III clinical study assessing the safety and efficacy of atacicept (formerly TACI-Ig) in patients with active lupus nephritis.

Lupus nephritis is an inflammation of the kidney caused by systemic lupus erythematosus, an autoimmune disease that can harm various organs in the body. Current treatment depends on the symptoms, but usually involves corticosteroids to suppress the immune system.

Patients with lupus produce abnormal antibodies that target their own tissues as opposed to foreign bodies, and atacicept, a recombinant fusion protein, has been shown to affect several stages of B-cell development and may inhibit the survival of cells responsible for making antibodies, the groups explained.

“Lupus nephritis patients need better treatment options to help them maintain kidney function and avoid kidney failure,” said Nicole Onetto, Senior Vice President and Chief Medical Officer at ZymoGenetics. ”Based on its mechanism of action and our early clinical data in lupus, we believe that atacicept has the potential to reduce disease symptoms and may help patients improve kidney function,” she added.

200-patient study
The one-year, randomised, double-blind study, which is being conducted under a Special Protocol Assessment agreement with US regulators, plans to enrol around 200 patients in around 80 sites in North America, Europe, Latin America and Asia. The primary endpoint in the trial is an improvement in renal function from baseline to week 52.

The companies are also developing atacicept as a potential treatment for other autoimmune diseases, such as rheumatoid arthritis and multiple sclerosis, as well as B-cell malignancies.