Results from a multicenter clinical trial in Belgium further demonstrated the therapeutic effects of rituximab, marketed by Genentech under the name Rituxan, to treat early diffuse cutaneous systemic sclerosis (dcSSc). The treatment not only improved skin symptoms but also prevented disease progression.
The results were discussed in a report titled, “Two years follow-up of an open-label pilot study of treatment with rituximab in patients with early diffuse cutaneous systemic sclerosis,” published in the journal Acta Clinica Belgica.
Rituximab was developed to specifically inhibit active immune B-cells. Because these immune cells are important mediators of the underlying mechanism that leads to dcSSc, the use of rituximab has become an attractive therapy for this disease.
The open-label Phase 2 clinical trial (NCT00379431) included 17 patients with early and severe dcSSc from three major treatment centers in Belgium: the University Hospital Ghent, UZ Leuven, and the Cliniques Universitaires Saint-Luc.
Patients were treated with 1,000 mg of rituximab administrated intravenously at day one and day 15 at the start of the trial, and from week 26 to 28. Patients also received 100 mg of the corticosteroid methylprednisolone, sold under the brand name Medrol, among others.
The team observed that two years after treatment, patients significantly reduced the degree of skin symptoms. This was demonstrated by a reduction of the modified Rodnan skin score (MRSS) from 25.5 at the beginning of the study to 12.6 two years later, a decrease of 51%.
“In our study, the skin involvement decreased steadily and significantly over a two-year follow-up period,” the researchers wrote in the report. “This finding is promising, since it was shown that the survival is significantly better in patients who show an improvement of the skin score, compared to those who do not,” they added.
The disease activity score was also significantly reduced with rituximab treatment, from a score of 4.1 at baseline to 1.5 at the 24th month.
Evaluation of lung, cardiac, and kidney involvement showed that the patients’ status remained clinically stable throughout the two-year follow-up period.
Seven serious adverse events were reported during the study, but six were considered unrelated to the treatment. One was associated with the rituximab plus methylprednisolone combo therapy.
“This study suggests that rituximab looks safe and tolerable and the results may suggest its efficacy on skin involvement, on overall disease activity and on stabilization of internal organ status in early dcSSc,” the team concluded.