Feb. 07, 2018

Atacicept Study Data Shows Promising Results

Study suggests new treatment may help to reduce lupus disease activity.

Findings from a global multi-center clinical trial investigating atacicept as a potential new lupus treatment were recently published and show promising results. Atacicept works by inhibiting two B-cell activation systems, called APRIL and BLyS. An earlier study suggested this approach was successful in reducing levels of B cells, plasma cells and serum immunoglobulin, all of which related to lupus disease activity.

The purpose of this phase IIb clinical study was to analyze the efficacy and safety of two different doses of atacicept in comparison to the placebo (an inactive or empty medication). In total, 306 individuals were enrolled in this double-blinded controlled study, which means neither the participant nor the physician know who is actually receiving the study medication.  Participants were assigned to one of three groups that would receive either 50mg of Atacicept, 75mg of Atacicept or a placebo. Each person received one weekly injection for 24 weeks and then were followed for another 24 weeks to monitor for safety. The efficacy of the treatment was determined by analyzing levels of disease activity as well as whether or not a flare occurred. Disease activity was calculated using the SLE Responder Index 4 and flares were assessed using the BILAG 2004. These are tools used to measure levels of disease activity to determine whether there are improvements among those who receive the study medication.

Using these measures, the researchers found that there was an overall trend toward a decrease in lupus disease activity; however it was not enough to meet the standard set by the primary endpoint (the end goal of the study). Additional analysis, however, found that some improvements were noted when the data were evaluated in more detailed ways. For example, improvements in disease activity were found when the investigators compared the levels of disease activity at the time of receiving the first injection, rather than the level measured when participants first enrolled in the study.  In addition, participants who received atacicept, and whose laboratory tests indicated that they had higher disease activity, showed significantly more improvement than those who received a placebo. Lastly, the risk of having a flare was reduced for those who received atacicept injections compare to those who received the placebo. Importantly, the study also found that there was no increase in the risk for having serious complications or infections among those who received atacicept.
Overall, while the study did not meet its endpoint, the findings suggest that Atacicept may be specifically effective for those with high levels of lupus disease activity.  The results suggest that additional clinical trials of atacicept are warranted.

Efficacy and Safety of Atacicept in Patients With Systemic Lupus Erythematosus
Results of a Twenty-Four-Week, Multicenter, Randomized, Double-Blind, Placebo-Controlled, Parallel-Arm, Phase IIb Study
Joan T. Merrill, Daniel J. Wallace, Stephen Wax, Amy Kao, Patricia A. Fraser, Peter Chang, and David Isenberg, on behalf of the ADDRESS II Investigators
ARTHRITIS & RHEUMATOLOGY, Vol. 70, No. 2, February 2018, pp 266-276.

Abstract available from the US National Library of Medicine