Abatacept Studied to Treat Diffuse Cutaneous Systemic Sclerosis
A recruiting phase 2 clinical trial sponsored by Dinesh Khanna, MD, MS at the University of Michigan, in collaboration with Bristol-Myers Squibb and National Institute of Allergy and Infectious Diseases (NIAID), is testing the hypothesis “that subcutaneous abatacept is safe and shows evidence of efficacy (improvement in modified Rodnan score [mRSS]) in patients with diffuse cutaneous systemic sclerosis compared to matching placebo.”
The study, “A Study of Subcutaneous Abatacept to Treat Diffuse Cutaneous Systemic Sclerosis (ASSET),” was initiated in June 2014 and is predicted to end in March 2016. During this time, 86 patients with diffuse cutaneous systemic sclerosis are expected to be treated.
Treatment arms are abatacept (Orencia) and placebo, with either being administered subcutaneously each week for one year. Following the year of treatment, patients will have the option of entering an open-label extension to receive abatacept, regardless of original treatment arm.
For evaluation, patients will be stratified by their disease duration: either less than 18 months or between 18 and 36 months. The primary measure for comparison is the mRSS. The researchers are predicting to see a lower mRSS in patients treated with abatacept than in patients treated with placebo. This would indicate the efficacy of abatacept in preventing or reversing disease progression in patients with an early stage of diffuse cutaneous systemic sclerosis, or in reversing progression in patients with a longer disease duration.
Only patients with diffuse cutaneous systemic sclerosis are included in the study. Limited cutaneous systemic sclerosis and sine scleroderma are in the exclusion criteria, but patients can have concurrent fibromyalgia and scleroderma-associated myopathy.
Currently, the only listed recruiting location is at the University of Michigan. In the near future, approximately 35 centers in the United States and Europe will recruit 86 patients, with the goal of analyzing data from at least 74 patients.
Bristol-Myers Squibb previously conducted a phase 1/2 clinical trial in conjunction with Stanford University. In contrast to the recruiting study, the completed study, “A Study to Evaluate the Safety and Efficacy of Abatacept in Patients With Diffuse Systemic Sclerosis (Scleroderma),” administered intravenous injections of abatacept or placebo. Injections were given on days 1, 15, and 30 before switching to monthly injections for a total of seven injections.
Abatacept is thought to be efficacious in treating diffuse cutaneous systemic sclerosis because it blocks T-cell activation. It is a recombinant fusion protein that is approved by the FDA to treat rheumatoid arthritis. If abatacept continues to move through the stages of clinical testing and development, the FDA may also approve it to treat diffuse cutaneous systemic sclerosis.