CellCept, Cytoxan Can Significantly Reduce Skin Thickening in Systemic Sclerosis, Study Shows

Long-term treatment with CellCept (mycophenolic acid) or Cytoxan (cyclophosphamide) can significantly reduce skin thickening in patients with systemic sclerosis (SSc), according to study published in the journal Arthritis Care & Research.

About 90 percent of SSc patients have thickened skin — a hallmark of this disease. As such, it is commonly used as a disease severity marker and outcome measure in clinical trials to differentiate the effects of potential disease-modifying drugs from placebo.

Several immune-modulatory drugs such as ‎Trexall (methotrexate) and Cytoxan have been studied as treatment for skin thickening and interstitial lung disease in SSc. However, until now, no one had performed an in-depth, long-term analysis of the effect of such therapies on skin thickening.

In the study, “Efficacy of mycophenolate mofetil and oral cyclophosphamide on skin thickness: post-hoc analyses from the Scleroderma Lung Study I and II,” researchers performed a post-hoc analysis of data collected from Phase 3 (NCT00004563) and Phase 2 (NCT00883129) scleroderma lung studies, to assess if CellCept and Cytoxan were better skin thickening management drugs than placebo.

The trials included 300 adults within seven years from onset of the first symptom of SSc. In the Phase 3 SLS study, each patient received daily oral Cytoxan or placebo, and in the Phase 2 SLS-II study, patients received either daily CellCept, Cytoxan, or placebo.

Using the modified Rodnan skin score (mRSS) as primary outcome measure, the authors found that both treatment regimens were beneficial. In fact, skin symptoms improved by about 30 percent in patients treated with either CellCept or Cytoxan compared to baseline after 24 months, while placebo-treated patients improved by 19 percent over the same period.

“In the SLS-II trial, two years of daily MMF [CellCept] and one year of CYC [Cytoxan] were each associated with clinically meaningful and statistically significant improvements in mRSS vs. placebo arm in patients with dcSSc [diffuse cutaneous SSc] over a 24-month period,” the authors wrote. “In conclusion, our data further support the role of MMF [CellCept] and CYC [Cytoxan] in the improvement in skin thickness in patients with SSc.”