Background/Purpose: Recently issued guidelines suggest that rheumatoid arthritis (RA) patients with previously treated solid malignancy may be treated as patients without such history (1). The recommendation is based on limited evidence and rheumatologists and patients are frequently hesitant to start biologic therapy after a cancer diagnosis. The objective of this study is to describe biologic utilization in real world RA patients following a malignancy diagnosis.

Methods: Patients (pts) with RA enrolled in the Corrona registry and diagnosed with a solid malignancy post enrollment were included in this analysis. Index date was defined as first visit after malignancy diagnosis. Proportion of pts initiating a biologic or targeted synthetic (ts) DMARD after diagnosis was estimated. Median time to the initiation of a biologic/tsDMARD after diagnosis was calculated using the Kaplan-Meier method and proportion initiating biologic treatment in 6-month time windows was estimated using the life-table method.

Results: Out of 42619 RA pts historically enrolled in Corrona, 934 pts had an incident solid malignancy after registry enrollment. 880 pts had at least 1 follow-up visit within 12 months after diagnosis and were included in the analysis. At index visit, mean disease duration was 14.1 years, mean age 66.6 years and 67% (n=592) were females. Mean CDAI for the population was 11.2 and 38.4% (n=329) of pts were in moderate or high disease activity. Total follow-up time after index date was 2585.6 person years. 41.7% (n=367) of the pts were treated with biologics/tsDMARDs within 12 months preceding malignancy and 30.7% (n=270) were on such agents at visit immediately following the diagnosis. Approximately 20% (n=170) initiated or switched a biologic/tsDMARD during the follow-up period, the majority of which started a TNF inhibitor (53.5%) The percentage of pts starting a biologic / tsDMARD and also a TNFi is shown in Table 1. The median time to initiation of the first biologic/tsDMARD was 118.7 months, approximately 10 years.

Conclusion: In real world practice, nearly one-third of RA patients continue therapy with biologic and ts agents after malignancy diagnosis and another one-third initiate biologic therapy within 5 years of solid malignancy diagnosis. The majority of biologic/tsDMARDs initiations was a TNFi. The proportion of biologic initiation is increasing in cancer survivors as time post diagnosis progresses.   Reference:

1.       Singh JA, Saag KG, Bridges SL Jr, et al. 2015 American College of Rheumatology Guideline for the Treatment of Rheumatoid Arthritis. Arthritis Rheumatol. 2016 Jan;68(1):1-26. doi: 10.1002/art.39480. Epub 2015 Nov 6. Review. Table