Alder BioPharmaceuticals, Inc, (Alder), a clinical-stage biopharmaceutical company, announced that clazakizumab, previously known as ALD518, met its primary endpoint in a follow-on phase 2b, dose-ranging clinical trial in adults with moderate to severe rheumatoid arthritis who have experienced an inadequate response to TNF inhibitors.

Alder plans to present the full results from the trial at an upcoming scientific meeting.

Clazakizumab met its primary endpoint, efficacy of clazakizumab versus placebo as assessed by the change in Disease Activity Score in 28 joints using C-reactive protein (DAS28-CRP) from baseline at week 12. Both the 25mg and 5 mg dosing groups were statistically significantly better than placebo at p<0.001.

Clazakizumab was well tolerated and there were no differences from placebo in terms of adverse events or laboratory safety data.

The follow-on phase 2b, dose-ranging trial was designed to determine safety and efficacy of clazakizumab in 140 patients with moderate to severe rheumatoid arthritis who were anti-TNF inadequate responders.

Clazakizumab is a humanized, monoclonal antibody, designed to block the pro-inflammatory molecule interleukin-6 (IL-6), which plays a key role in the inflammatory cascade leading to the inflammation, swelling, pain and destruction of large and small joints associated with arthritis.

Randall C. Schatzman, Ph.D., president and chief executive officer of Alder, said "These positive safety and efficacy findings in patients with rheumatoid arthritis provide additional support for the promise of clazakizumab as we seek a new partner to continue developing this monoclonal antibody for the treatment of autoimmune and inflammatory diseases."

Alder BioPharmaceuticals, Inc. is a clinical-stage biopharmaceutical company that discovers, develops and seeks to commercialize therapeutic antibodies with the potential to meaningfully transform current treatment paradigms.