UCB’s epratuzumab provides a significant reduction in disease activity in patients with moderate to severe active systemic lupus erythematosus, according to new data presented at the European League Against Rheumatism (EULAR) meeting in Rome.

Data from the Phase IIb study, EMBLEM, suggests epratuzumab is clinically effective according to the company and plans are underway to begin two Phase III trials later in the year. Epratuzumab, licensed from Immunomedics, is a first-in-class humanised monoclonal antibody targeting CD22 and modulating B-cell activity and rheumatologists are excited about the data, given the number of failed attempts to get a lupus drug to market.

EMBLEM was a 12-week, multicentre, Phase IIb trial designed to define a dose and regimen in patients with moderate to severe lupus. Patients were randomised to one of six regimens: placebo, epratuzumab cumulative dose 200, 800, 2,400 or 3,600mg in equal divided doses using two every other week infusions or epratuzumab 2400mg delivered as four equal infusions a week apart.

Statistically significant response rates in favour of epratuzumab, double those in the placebo group, were seen in the 600mg weekly group and in the combined group of all patients who received a cumulative dose of 2,400mg during the 12-week treatment cycle. A UCB spokesperson said: “Following these findings, we anticipate that in the second half of 2010 we will initiate two Phase III studies, EMBODY 1 and 2, for epratuzumab. We are still in discussion with the regulatory authorities on the exact design of these trials.”

Lead investigator Daniel Wallace of the David Geffen School of Medicine at UCLA in California, said: “We have not seen a new drug approved to treat lupus in over fifty years. This short study suggests epratuzumab can improve patients’ health as quickly as week 12 of treatment.”

Lupus is a chronic and potentially fatal autoimmune disease with a variable and unpredictable course. Antibodies are generated against the body’s own nuclear proteins causing the immune system to attack its own cells and tissues resulting in inflammation and tissue damage, which can occur in any part of the body. By Rhonda Siddall in Rome