Subjective Tolerability Drives PsA Treatment Decisions in Cohort Study

Anne Constanze Regierer, MD

Credit: German Rheumatism Research Centre

Patients with psoriatic arthritis (PsA) did not have notable differences in clinical parameters before initiating biologic (b) and targeted synthetic (ts) disease modifying anti-rheumatic drugs (DMARDs) mono or methotrexate (MTX)-combination therapy and treatment decisions were driven by subjective tolerability of MTX.¹

“Under the principle of shared decision-making, physicians collaborate with patients both engaging in the decision-making process and reaching consensus on treatment choices. However, in PsA, when initiating b/tsDMARDs, it remains uncertain whether specific variables influence the decision-making process regarding continuation or discontinuation of MTX²,” lead investigator Anne Constanze Regierer, MD, head, Registry Research in Rheumatology Research Group, Epidemiology program, German Rheumatism Research Centre Berlin, Germany, and colleagues wrote.¹ “The aim of this study was to compare clinical and patient reported baseline parameters of PsA patients starting b/tsDMARD monotherapy with those starting such treatment in combination with MTX as well as to assess the drug retention rates in the 2 groups.”

Regierer and colleagues conducted a prospective longitudinal cohort study including 1305 patients with PsA and axial spondyloarthritis (axSpA), termed the RABBIT-SpA study In the study, patients with PsA were stratified into 2 groups according to whether they were starting b/tsDMARD as monotherapy or in combination with MTX. Treatment retention was compared between the groups by drug survival analysis.

The investigators found that 69% of the patients (n = 900) started b/tsDMARDs as monotherapy while 31% (n=405) started b/tsDMARDs in combination with MTX. Patients between groups had similar involvement in clinical domains like skin, nail and joint affection, dactylitis, enthesitis and axial involvement at baseline. The combination group did have higher satisfaction concerning tolerability of the previous treatment at treatment start than the monotherapy group.¹

The combination group had a mean drug retention time of 15.2 months and the monotherapy group had a mean drug retention time of 14.4 months. At 6 months, 48% of the combination group and 66% of the monotherapy group were still on their original treatment; at 12 months, these proportions were 48% and 67%, respectively. Adjusted treatment retention rates were found to be similar between groups (P = .04).

Discontinuation rates were also similar between groups, with 36% of the monotherapy group and 32% of the combination group discontinuing due to adverse events (AEs), and 61% of the monotherapy group and 57% of the combination group discontinuing due to ineffectiveness. Accordingly, rates of AEs were similar, with 45% of the combination group and 42% of the monotherapy group experiencing at least 1 AE, and 10% of the combination group and 14% of the monotherapy group experiencing at least 1 severe AE.¹

The investigators also specifically compared 437 patients treated with first-line b/tsDMARD monotherapy and 255 patients with first-line b/tsDMARD+MTX combination therapy and found that results were similar to the rest of the cohort study.¹

“In conclusion, our study contributes to the understanding of treatment decision-making in PsA. The choice between b/tsDMARD monotherapy and combination with MTX is mainly based on patient preference and drug tolerability. This highlights the role of patient satisfaction in determining treatment choices,” Regierer and colleagues concluded.¹

REFERENCES

1. Regierer AC, Kiefer D, Schett D, et al. No difference in clinical parameters and drug retention in PsA patients receiving b/tsDMARD monotherapy versus combination with methotrexate: data from the RABBIT-SpA registry. RMD Open 2024;10:e004389. doi: 10.1136/rmdopen-2024-004389

2. Gossec L, Kerschbaumer A, Ferreira RJO, et al. EULAR recommendations for the management of psoriatic arthritis with pharmacological therapies: 2023 update. Ann Rheum Dis 2024;83:706–19. doi:10.1136/ard-2024-22553