SAT0246 At which point and for which reasons are oral mtx formulations switched to injectable ones in ra patients? combined results from 3 independent observational and clinical trials

Background: MTX is considered as a cornerstone in RA treatment since the 1990s and its injectable forms have proven their enhanced clinical and pharmacological efficacy and safety in case of insufficient response or poor tolerance of oral formulations. Few data are available considering the timepoint at which the route of administration is changed in current practice. Objectives: The objective of this work was to investigate across 3 independent trials if there was a consistency in patterns of MTX oral ->injectable switches in terms of RA characteristics, MTX dosages (before and after the switch) and reasons of passage. Methods: Three trials were considered for this work: 1/STRATEGE (observational study designed to investigate the therapeutic strategies used in current practice in RA patients insufficiently responding to initial MTX monotherapy), 2/APRiM (observational study aimed to investigate the treatment adherence of RA patients switching from oral to injectable MTX or between two different MTX prefilled syringes) and 3/SELFi (phase III randomized trial aiming to compare a new MTX autoinjector to the historical MTX prefilled syringe in terms of treatment adherence and functional capacity in RA patients at 6 months). In all three studies we selected baseline data concerning patients switching from oral to injectable MTX at the inclusion visit. Results Consistent data were observed across the three considered trials concerning the oral/injectable MTX switch. It occurs after about 3 years of treatment, at a DAS28 of 4 and at an average dose of 15 mg/wk (which is consistent with bioavailability data shown before). In most situations, MTX dosage is unchanged or very slightly raised at the switch timepoint. The main switch reasons were “non-achievement of treatment target” and “RA worsening”, the safety reasons were mentioned only in 5% of cases. Conclusions: Our work showed a consistent pattern across 3 independent trials concerning the oral/injectable MTX switch. It generally occurs at 15 mg/wk, the new injectable dosage being either unchanged or very slightly raised as compared to the last oral one. Surprisingly, the MTX route of administration seems to be modified mostly for efficacy reasons, safety issues being anecdotal. Reference 1Schiff MH, et al. Ann Rheum Dis2014. Disclosure of Interest: R.-M. Flipo Consultant for: Nordic Pharma, A. Saraux Consultant for: Nordic Pharma, C. Hudry Consultant for: Nordic Pharma, C. Gaujoux-Viala Consultant for: Nordic Pharma, E. Senbel Consultant for: Nordic Pharma, S. Trope Consultant for: Nordic Pharma, E. Zinovieva Employee of: Nordic Pharma, H. Herman-Demars Employee of: Nordic Pharma