W Ye1, M C Fifield1,2, A Mayhew3, S Nasser1,4, Ajk Östör1,2. 1. a School of Clinical Medicine , University of Cambridge , Cambridge , Cambridgeshire , UK. 2. b Rheumatology Clinical Research Unit , Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust , Cambridge , Cambridgeshire , UK. 3. c Infusion Service , Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust , Cambridge , Cambridgeshire , UK. 4. d Department of Allergy , Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust , Cambridge , Cambridgeshire , UK.