Methotrexate for Primary Biliary Cirrhosis: Who Is to Be Trusted?

Excerpt

Primary biliary cirrhosis (PBC) remains a puzzling disease. Its etiology recognizes both genetic and environmental influences, as well epitomized by the incomplete concordance rate among monozygotic twins [1]. Most recently, genomewide association studies provided a number of candidate genes which, however, are found only in subgroups of patients [2]. In a complementary fashion, several environmental factors have also been identified as putative triggers of PBC [3]. Nevertheless, numerous enigmas remain in PBC pathogenesis and clinical features. Among the latter, poor response of PBC to immunosuppressants, despite evidence supporting the immune-mediated injury and the proinflammatory cascade, remains a clinical challenge. Ursodeoxycholic acid (UDCA) is currently the only accepted treatment for PBC and may delay but not halt the progression of the disease [4]. A few studies suggested increased transplant-free survival, but a meta-analysis of published trials did not confirm this finding [5]. Interestingly, UDCA has limited immunomodulatory effects while acting on biliary secretion and protecting from the potentially membranolytic detergent effect of retained endogenous bile acids [6]. For these reasons, the combination of UDCA and immunosuppressants appeared an obvious and rational development but substantially failed for most drugs [7], while longer study periods are warranted for recent candidates such as budesonide [8], B cell depleting rituximab [9], and farnesoid X receptor agonist obeticholic acid [10]. The study by Dr. Kaplan and Colleagues included in this issue of Digestive Diseases and Sciences [11] raises some doubt against these quite established observations. …