Double-blind, Randomized, 8-week Placebo-controlled followed by a 16-week open label extension study, with the LPA1 receptor antagonist SAR100842 for Patients With Diffuse Cutaneous Systemic Sclerosis

Abstract

BACKGROUND Preclinical studies suggest a role for lysophosphatidic acid (LPA) in the pathogenesis of systemic sclerosis (SSc). OBJECTIVES SAR100842, a potent selective oral antagonist of LPA1 receptor, was assessed for safety, biomarkers and clinical efficacy in patients with diffuse cutaneous SSc (dcSSc). METHODS An 8-week double-blind, randomized, placebo-controlled study followed by a 16-week open label extension with SAR100842 was performed in patients with early dcSSc and a baseline Rodnan skin score (mRSS) of at least 15. The primary endpoint was safety during the double-blind phase of the trial. Exploratory endpoints included the identification of a LPA-induced gene signature in patients 'skin. RESULTS 17 of 32 subjects were randomized to placebo and 15 to SAR100842; 30 patients participated in the extension study. The most frequent adverse events reported for SAR100842 during the blinded phase were headache, diarrhea, nausea and fall and the safety profile was acceptable during the extension part. At Week 8, mean reduction in mRSS was numerically greater in the SAR100842 compared to placebo (mean change [SD]: -3.57 [4.18] versus -2.76 [4.85]; difference [95% CI]: -1.2 [-4.37 to 2.02], p=0.46). A greater reduction of LPA related genes was observed in skin of SAR100842 group at Week 8, indicating LPA target engagement. CONCLUSION SAR100842, a selective orally available LPA receptor antagonist, was well tolerated in patients with dcSSc. MRSS improved during the study although not reaching significance, and additional gene signature analysis suggested target engagement. These results need to be confirmed in a larger controlled trial. This article is protected by copyright. All rights reserved.