Background: Biosimilar infliximab (Inflectra™/Remsima™) has been available in the United Kingdom from 2015. We present data from the UK Inflammatory Bowel Disease (IBD) audit programme demonstrating changing patterns of biological use, including the use of biosimilars.
Methods: Participating hospitals prospectively identified adult and paediatric patients who were newly started on biological therapies for the treatment of IBD between 1 March 2015 and 29 February 2016. Data was submitted by 138 adult trusts/health boards and 19 specialist paediatric sites. Demographics, disease and safety data were collected on 2722 adult and 278 paediatric patients. Of these patients 1977 had Crohn's disease (CD), 950 had ulcerative colitis (UC) and 73 had IBD unclassified (IBDU). In patients with CD, response to treatment was defined as a decrease of >3 in HBI for adults and a decrease of >15 in PCDAI for paediatrics.
Results: Median time from diagnosis to treatment in adult patients has fallen from 4.5 years in 2012 to 3.8 years in 2016 (p=0.026). 60% (1388/2308) adult and 47% (109/230) paediatric patients had complete pre-treatment screening for opportunistic infections. Over the last four rounds of audit median pre-treatment Harvey-Bradshaw Index (HBI) in adult patients has fallen from 9 to 7.
In 2016 800 (29%) adult and 175 (63%) paediatric patients were started on infliximab (Remicade®) compared with 596 (22%) adult and 82 (29%) paediatric patients started on biosimilar infliximab. Of the patients being treated with infliximab (Remicade®) 81% (651/800) of adults and 95% (167/175) of paediatrics were on any steroid or immunosuppressant therapy at time of initial treatment compared to 80% (474/596) adults and 95% (78/82) paediatrics being treated with biosimilar infliximab. A response was shown in 84% (59/70) of adult and 86% (19/22) of paediatric patients following 3 months of treatment with biosimilar infliximab (Inflectra/Remsima) compared with 85% of adult (114/134) and 85% (28/33) of paediatric patients treated with infliximab (Remicade). 10% (82/855) adult patients and 5% (6/121) paediatric patients had an adverse reaction recorded at 3-month follow-up. The most common reaction was a rash. Infection was seen in 1% (9/855) of adult patients and there were no reported malignancies.
Conclusions: The pattern of use of biological therapies in IBD has changed over the course of the UK IBD audit with earlier use in milder disease. Short term safety and efficacy of biosimilar infliximab (Inflectra/Remsima) appear equivalent to infliximab (Remicade). The adoption of these agents is clinically appropriate and their universal adoption will be reflected by a significant cost saving.