Methotrexate displays a lack of competition for folate-receptor-binding sites and a nonfolate-receptor-targeted anti-arthritic activity. In an identical dosing fashion as was carried out for EC0746 in Figure 4, adjuvant-induced arthritis rats (n = 5) were treated subcutaneously with methotrexate (MTX) (250 nmol/kg biweekly) for 2 weeks without or with a 500-fold molar excess of EC0923 as the folate competitor. Anti-arthritic activities are shown: (a) arthritis score; (b) percentage increases in paw and spleen weights; and (c) percentage change in body weight. ns, not significant.
Lu et al. Arthritis Research & Therapy 2011 13:R56 doi:10.1186/ar3304