Background Combination therapy with a tumour necrosis factor inhibitor plus methotrexate (MTX) has been shown to be effective for achieving and sustaining remission in patients with rheumatoid arthritis (RA). The potential for continuation with etanercept (ETN) monotherapy once remission has been achieved was highlighted recently.1 As MTX is not well tolerated in some patients, we carried out a subanalysis of the COMET study2 to explore the effect of ETN monotherapy in patients who had achieved disease remission with ETN+MTX.
Objectives To evaluate the efficacy of ETN monotherapy compared with ETN+MTX combination therapy at week 104 in RA patients who achieved disease remission with ETN+MTX at week 52 in the COMET study (NCT00195494).
Methods Participants in the COMET study received combination therapy (50 mg/week ETN+MTX) or MTX monotherapy for 52 weeks in Period 1. This subanalysis focuses on the patients in the ETN+MTX arm who either continued ETN+MTX therapy (ETN+MTX/ETN+MTX) or received ETN monotherapy (ETN+MTX/ETN) in Period 2 (weeks 52-104). Only those patients who achieved week 52 remission were included in the subanalysis, and the proportion who achieved week 104 remission were analysed. Both Disease Activity Score in 28 joints (DAS28) remission (DAS28<2.6) and Boolean remission (tender joint count≤1, swollen joint count≤1, C-reactive protein≤1 mg/dl and patient global assessment≤1 (0-10 scale)) were analysed. Comparisons between treatment groups were performed using Fisher's exact test for categorical parameters or one-way ANOVA for continuous parameters, and used the Last Observation Carried Forward imputation method.
Results Demographic and baseline disease activity characteristics were similar between the two treatment groups and between week 52 DAS28 and Boolean remission vs non-remission groups, with the exception of significantly more males and fewer females who were in DAS28 remission compared with non-remission (48% vs 29% for males and 52% vs 71% for females in the ETN+MTX/ETN+MTX vs ETN+MTX/ETN groups, respectively; P=0.029). At week 104, DAS28 remission was maintained by 46/54 (85.2%) of patients in the ETN+MTX/ETN+MTX group vs 44/63 (69.8%) patients in the ETN+MTX/ETN group (P=0.077), and Boolean remission was achieved by 18/23 (78.3%) of patients in the ETN+MTX/ETN+MTX group vs 20/28 (71.4%) patients in the ETN+MTX/ETN group (P=0.749).
Conclusions There were no significant differences in either DAS28 remission or Boolean remission at week 104 in the efficacy of ETN monotherapy vs ETN+MTX therapy in RA patients who had achieved disease remission on ETN+MTX at week 52. Remission data from the more stringent Boolean remission criteria indicate that ETN monotherapy may be adequate in RA patients who have achieved remission following combination therapy, which may be useful for the continued treatment of patients who cannot take MTX.
Pope JE, et al. Ann Rheum Dis. 2014;73:2144-51.
Emery P, et al. Lancet. 2008;372:375-82.
Acknowledgements The COMET study (NCT00195494) was funded by Pfizer Inc. Medical writing support was provided by Rina Passmore of Engage Scientific Solutions, and was funded by Pfizer Inc.
Disclosure of Interest P. Emery Grant/research support from: BMS, Roche, Chugai, MSD, Pfizer, AbbVie, Novartis and UCB, Consultant for: BMS, Roche, Chugai, MSD, Pfizer, AbbVie, Novartis and UCB, H. Jones Employee of: Pfizer Inc, L. Marshall Employee of: Pfizer Inc, A. Szumski Employee of: Pfizer Inc, U. Kerkmann Employee of: Pfizer Pharma GmbH, B. Kola Employee of: Pfizer Ltd