Corbus Readies Pivotal Phase 3 Trial of Anabasum, Possible Scleroderma Treatment

Corbus Pharmaceuticals is planning a global Phase 3 trial to assess anabasum (JBT-101) as a treatment for scleroderma. If successful, the company plans to apply to regulatory authorities, asking that anabasum be the first specifically approved treatment for scleroderma.

The study, which Corbus calls RESOLVE-1, will enroll 354 patients and largely follows a similar set-up as the earlier Phase 2 study of the compound.

“We are delighted to initiate our Phase 3 RESOLVE-1 study on schedule. The start of this study is an important milestone for Corbus as we continue advancing anabasum for the treatment of rare, serious chronic inflammatory and fibrotic diseases,” Yuval Cohen, CEO of Corbus, said in a press release.

In November 2017, Corbus announced that the majority of patients in the Phase 2 trial (NCT02465437) of anabasum — and a long-term follow-up study — had improved skin symptoms and lower arthritis severity. Researchers also reported lower disability levels and a slowed decline in lung function with the treatment.

The RESOLVE-1 trial will randomly assign treatment with either anabasum 5 mg or 20 mg, or a placebo, twice a day for 52 weeks. Researchers will examine changes in skin fibrosis using the modified Rodnan Skin Score (mRSS) as the main outcome measure.

Secondary outcomes will include additional patient- and physician-reported measurements, as well as measures of lung function.

“Efficacy and safety results of the double-blinded, placebo-controlled portion and the open-label extension of the Phase 2 study in systemic sclerosis have been promising, fueling my optimism for this Phase 3 study,” Robert Spiera, director of the Vasculitis and Scleroderma Program at the Hospital for Special Surgery and a professor of Clinical Medicine at Weill Cornell Medical College.

Spiera underscored that, in contrast to commonly used immunosuppressants, anabasum has a mechanism of action that allows it to target fibrosis and inflammation without suppressing the immune system.

“Even though they are not specifically indicated for systemic sclerosis, currently available immunosuppressive medications are often used to control disease activity in systemic sclerosis with limited efficacy,” said Spiera, who is principal investigator for the RESOLVE-1 study.

“Further, these drugs can cause side effects including increased risk of infection and require regular monitoring using blood tests,” he added.

The Phase 2 trial explored anabasum as an add-on to standard scleroderma treatment, which were mostly immunosuppressants.

The Phase 3 trial will include 70 sites in North America, Europe, Israel, Japan, South Korea, and Australia, the company said. Corbus aims to finish dosing patients by the end of 2019, which would allow regulatory submissions to be filed by mid-2020.

Anabasum has been designed an Orphan Drug and granted Fast Track status by the U.S. Food and Drug Administration as a potential scleroderma treatment, and designated an Orphan Drug by the European Medicines Agency.