of around 90%. Older patients ready to switch and female patients were recorded as less interested in switching. Ethnicity difference was also noted as White British were less likely (79%) to switch. Reasons not switching varies from anxiety (17%), medical reasons (33%), faith in the originator drugs, previous reaction, and perception of side effects. We also compared an infliximab switch and noted a slightly lower rate in switching (85.45%). These non-switchers accounted for (14.55%) compared to etanercept. It is interesting to note that only one patient switched back to the originator drug, showing a larger retention rate in the infliximab groups. We reviewed the reasons for switching back to originator and noted the reasons as lack of confidence in the drug (17%), rather than inefficacy. Conclusion: This is a small group retrospective audit with limitations. We observed that older patients prefer not to switch and with differences in ethnicity. Effective patient education will help to switch patient from originators to biosimilars and maintain the retention rate. This can be achieved by developing a patient expert group on biosimilar switchers, and also one-to-one education by health professionals. Developing more patient-centered educational material on biosimilars in South Asian languages will help to improve the biosimilar switch. Disclosures: A. Moorthy: Honoraria; Speaker Fees and Sponsorship for Conferences. K. Hall: None. S. Walton: None. 101 EFFICACY OF TOCILIZUMAB USE IN GIANT CELL ARTERITIS (GCA) AND TAKAYASU ARTERITIS (TA) PATIENTS ALLOWING GLUCOCORTICOID DOSE REDUCTION Malinder Singh 1 , Naomi Scott 1 and Barbara Hauser 1 1 Rheumatology, Western General Hospital, Edinburgh, UNITED KINGDOM Background: Tocilizumab is an interleukin-6 receptor alpha inhibitor which has been shown to allow rapid glucocorticoid (GC) tapering whilst maintaining disease remission. Tocilizumab was recently recommended in patients with giant cell arteritis (GCA) by NICE and SMC but its use is restricted to 1 year. In a real-life large vessel vasculitis cohort, we have audited the efficacy of tocilizumab use in allowing GC dose reduction, inducing remission and the current required treatment length. Methods: A single centre pharmacy database allowed the identifica- tion of all patients with large vessel vasculitis (LVV) who were started on tocilizumab in the last 2 years. We collected health record data on demographics, concomitant disease-modifying anti rheumatic drug (DMARD) use, length of tocilizumab use, reported LVV flares, adverse events and GC reduction. Results: We have identified 13 patients with LVV, nine patients with GCA and four patients with TA. Amongst the nine GCA patients, eight patients had refractory GCA and one patient had relapsing disease. Three (33%) GCA patients had confirmed extracranial vessel involve- ment. The majority of patients (85 %, n ¼ 11) were women and mean BMI of all patients were 32.2  9.8 kg/m 2 and five (35.7%) patients were morbidly obese (BMI >35 kg/m 2 ). Most patients (n ¼ 12) received weekly subcutaneous tocilizumab injections (162 mg) and 1 patient received intravenous infusions at 2mg/kg. The majority of patients (77%) were on concomitant DMARD therapy in the form of methotrexate (n ¼ 8 ), azathioprine (n ¼ 1) and mycophenolate mofetil (n ¼ 1). Tocilizumab use resulted in ten (77%) patients achieving remission without a reported flare and the majority (n ¼ 9, 69%) of patients achieved 50% reduction in GC dose after 4 months of therapy. Mean length of treatment with tocilizumab for GCA patients was 11 6 months and four out of nine (44%) GCA patients required tocilizumab for over 12 months. Two patients had to stop tocilizumab due to severe adverse events (diverticulitis with bowel perforation and severe pneumonia). Conclusion: Our audit confirms that tocilizumab is an effective treatment for achieving remission in relapsing and refractory GCA and TA patients and allows rapid tapering of GC. Many patients in our cohort benefit from prolonged (>1 year) treatment with tocilizumab which is in contrast to current guidelines. Additionally, a number of patients requiring tocilizumab were morbidly obese. Disclosures: M. Singh: None. N. Scott: None. B. Hauser: None. 102 ASSESSING REASONS FOR PATIENTS SWITCHING BACK FROM BIOSIMILAR ETANERCEPT THERAPY TO ORIGINATOR PRODUCT 1 , Kavina Shah 1 , Ahmad Al-Abdulla 1 and 1 Imperial College Healthcare NHS Trust, London, Background: Biosimilar therapies are required to be clinically similar to their corresponding originator product, regarding safety and efficacy. Recent guidance states most trials comparing biosimilar and originator products have been undertaken on patients newly initiated on biological therapy. There is limited data on patients previously established on originator product before being switched. Clinical observation suggests a number of patients have switched back from biosimilar etanercept (Benepali) to originator product (Enbrel) - our aim was to explore the reasons behind this. Methods: Using pharmacy funding and dispensing databases, patients switched from Enbrel to Benepali and subsequently switched back to originator product were identified. Inclusion criteria included adult rheumatology patients, who were prescribed etanercept. Patients with rheumatoid arthritis (RA) had Disease Activity Score in 28-joints (DAS28) calculated before their initial switch to Benepali and subsequently prior to being switched back to Enbrel. Results: Over a 20-month period, 27 of 202 patients (13.4%) switched initially to Benepali were switched back to Enbrel. 16 had RA - other indications included psoriatic arthritis (n ¼ 5) and ankylosing spondy- litis (n ¼ 3). 78% of patients reported worsening of symptoms as the reason for switching back. Other reasons included skin reactions (n ¼ 1) and painful injections (n ¼ 1). 7 out of 9 RA patients with documented DAS28 scores had an increase in DAS28 score post- switch to Benepali (Table 1). Average change in DAS28 during this period was þ1.32 (p ¼ 0.06). Average changes in DAS28 components were: Tender Joint Count þ5, Swollen Joint Count þ0.55, Visual Analogue Scale (VAS) þ25.56 and Erythrocyte Sedimentation Rate þ9.89. Conclusion: 13.4% of patients switched to Benepali after having been established on Enbrel required switching back. The majority of patients who switched back to Enbrel reported subjective worsening of disease symptoms with Benepali. Analysis of RA patients demonstrated increased DAS28 scores (>1.2) during the period of being switched to Benepali - mainly due to increases in visual analogue scores (statistical insignificance may be due to low sample size). This may suggest a subjective component contributes towards intolerance of Benepali - hence consideration of patient education during initiation of biosimilar treatments could be significant in improving compliance. Disclosures: C. Dahanayake: None. K. Shah: None. A. Al-Abdulla: None. M. Carulli: None. 103 RETROSPECTIVE AUDIT OF SEPTIC ARTHRITIS IN COVENTRY AND WARWICKSHIRE NHS TRUST: 5-YEAR DATA Arani Vivekanantham 1 , Meyada Ali 1 , Megan Rutter 1 , Amandeep Kahlon 1 , Andrew Metcalfe 2 and Shirish Dubey 1 1 Rheumatology, University Hospital Coventry, Coventry, UNITED KINGDOM, and 2 Trauma and Orthopaedics, University Hospital Coventry, Coventry, UNITED KINGDOM Background: Septic arthritis (SA) is a rheumatological emergency, associated with individual morbidity, mortality and prolonged admis- sions. The incidence is 2-10 people per 100,000. There is data to suggest that the increasing frequency of joint injections and arthroscopies is contributing to a rising incidence of SA. The aims of this audit were to investigate: the incidence of native joint septic arthritis in the adult population in a secondary care hospital in the UK; to what degree immunosuppression is a feature in such cases; what proportion of SA cases were deemed iatrogenic. Methods: All inpatient admissions between 2007-2011 to University Hospital Coventry and Warwickshire (UCHW) NHS Trust, which covers an estimated population of 550,000, were analysed. Patients were retrospectively identified on the basis of the International Classification of Diseases (ICD)-10 coding generated following discharge. Exclusion criteria included patients aged <18, diabetic foot, prosthetic joint infections and those who on clinical review of notes were not thought iii84 Wednesday 1 May 2019 INVITED SPEAKERS ABSTRACTS Downloaded from https://academic.oup.com/rheumatology/article/58/Supplement_3/kez108.009/5444740 by guest on 25 April 2022