ALGORITHM IDENTIFYING CHRONIC INFLAMMATORY DISEASES TREATED BY BIOTHERAPY AND/OR TARGETED SYNTHETIC TREATMENTS IN OUTPATIENT CARE IN FRANCE: FEASIBILITY, PRELIMINARY RESULTS, AND IMPACT OF COVID-19

Background: Discriminating chronic inflammatory diseases under biotherapy and/or targeted synthetic treatments (B/TST) using medico-administrative databases are challenging but required for medico-economic analyses focusing on these diseases. Objectives: The objective was to evaluate the feasibility of using a medication dispense data in order to identify patients with chronic inflammatory diseases under B/TST in outpatient care setting and evaluate the impact of COVID-19 in France Methods: LRx contains all anonymized medication dispenses prescribed in outpatient care in a representative panel of French retails pharmacies, including data of near 40 million patients. Patients having at least one B/TST delivered in 2019 were selected. An algorithm was constructed using different steps, including a machine learning step by transfer learning applied in patient classified as having a rheumatologic condition in order to differentiate rheumatoid arthritis (RA) from spondyloarthritis (SA). We numbered 190,640 patients, of which 87.8% were classified in one of the following diseases: RA, SA, psoriatic arthritis (PA), psoriasis, inflammatory bowel diseases (IBD) (extrapolated data to France). Descriptive analysis was performed. The impact of COVID-19 on biotherapy initiation was evaluated during the lockdown period (W2-W19 2020) in these different conditions. Results: Among the 167,468 patients under B/TST, 20.7%, 18.4%, 6.5%, 37.9% and 16.5% were considered as having a psoriasis, IBD, PA, RA, and SA, respectively. Female patients were more frequent in RA and PA (> 60%); younger (< 20 years) and older patients (74 years) were found in patients with IBD (5.7%) and RA (12.6%), respectively. Contrasting with IBD, SA, and RA patients were mainly under anti-TNF treatment (> 90% for IBD and SA, 73.5% for RA), psoriasis and PA patients received a range of broadly well-balanced of B/TST. Among the immunosuppressant, methotrexate was mostly prescribed in RA (58.4%), PA (34.1%), and psoriasis (14.1%), and azathioprine in IBD (19.9%). Oral corticosteroid delivered at least 4 times in 2019 were mostly found to be associated with a RA condition (28%). A significant decrease of biotherapy initiation was observed during the lockdown in France in patients with IBD (-20%, p=0.03) and psoriasis (-54%, p<0.0001), not significant decrease in patients with SA (-6%) and increase in RA patients (+23%). Conclusion: The algorithm was able to identify patients with chronic inflammatory diseases under B/TST delivered in outpatient care and will allow to follow-up its management and study the COVID-19 impact on biotherapy initiation. An external validation needs to be performed Disclosure of Interests: None declared Citation: Ann Rheum Dis, volume 80, supplement 1, year 2021, page 901Session: COVID-19 (POSTERS only)