Treatment with Corbus Pharmaceuticals’ investigative therapy lenabasum (formerly known as anabasum) significantly improves the symptoms of diffuse cutaneous systemic sclerosis in a Phase 2 open-label extension study.
The latest results from the trial were recently discussed at the 2018 Annual European Congress of Rheumatology (EULAR) held in Amsterdam, the Netherlands.
The open-label extension study (NCT02465437) enrolled 36 patients with diffuse cutaneous systemic sclerosis who were treated with 20 mg lenabasum twice a day after they completed 12 weeks of treatment in Part A of the placebo-controlled Phase 2 trial.
Participants were allowed to continue their standard-of-care treatments in addition to lenabasum in Part B of the trial. To date, 27 participants have completed one year of follow-up in the extension study.
Initial data from the Phase 2 trial revealed improvements in several efficacy outcomes. According to data presented at the meeting, 38% of patients treated with lenabasum experienced improvements in inflammation, and 43% saw improvements in fibrosis, whereas only 15% of patients treated with placebo showed such positive responses.
Data after one year of treatment with lenabasum showed that patients experienced an improvement by 92% on their mean CRISS score (Combined Response Index in diffuse cutaneous Systemic Sclerosis) — a measure of disease state and organ damage — compared to the beginning of the extension study.
Also, skin thickness improved by 9.4 points, as determined by the modified Rodnan Skin Score, compared to the start of the trial. More than 77% of participants experienced at least a 5 point improvement, which is already considered medically meaningful.
These positive results were accompanied by improvements in patients who reported itchy sensations and skins manifestations. Global health assessment also revealed the treatment was beneficial, achieving a stable lung function by the end of the study similar to the one at the start.
During the open label extension, there were no severe or serious treatment-related adverse effects reported. Seven patients (13.9%) experienced adverse events related to lenabasum treatment during the open-label dosing, which was a lower incidence than the reported 25.9% during the 12-week treatment in the first part of the trial
“Our results are very encouraging and reinforce the positive findings from the double-blinded placebo-controlled part of the study with regard to safety and tolerability,” Robert Spiera, MD, director of the Scleroderma and Vasculitis Program at the Hospital for Special Surgery, Weill Cornell Medical in New York City and principal investigator of the Phase 2 study, said in a press release.
“We look forward to continuing our investigations to assess the role of lenabasum as a new treatment option for patients with diffuse cutaneous systemic sclerosis,” Spiera added.
Corbus is currently recruiting for its international Phase 3 RESOLVE-1 trial (NCT03398837), which will assess the effectiveness and safety of lenabasum as a treatment for diffuse cutaneous systemic sclerosis.
The Phase 3 study is expected to enroll about 350 participants who have had diffuse cutaneous systemic sclerosis for at least six years. It will conducted across 60 sites in North America, Europe, Australia, and Asia. Patients will be randomized to receive either 5 or 20 mg of lenabasum or a placebo twice daily for 52 weeks.
Lenabasum is an engineered small molecule that was designed to selectively activate the cannabinoid receptor type 2, or CB2, in immune cells and fibroblasts.
Through activation of CB2, lenabasum will trigger cellular signals that will reduce inflammation, promote bacterial clearance, and prevent fibrosis.