Abstract Background/Aims Timely access to intravenous immunosuppressant therapy is essential to effectively manage systemic vasculitis; however, significant variations in care and outcomes exists across centres. We systematically evaluated access to treatment for ANCA-associated vasculitis across the UK and Ireland. Methods This multi-method study included: a survey of 87 UK and Ireland Vasculitis Society sites and 11 Scottish Health Boards between Nov 2020 and June 2021; interviews with staff and patients with systemic vasculitis. Survey data was analysed descriptively. Interviews were audio or video recorded and analysed thematically. Results 59 responses from 51 Trusts/Health Boards across Scotland (n = 11), England (n = 33), Wales (n = 2), and Ireland (n = 5) included equal numbers of rheumatology and nephrology vasculitis services across diverse healthcare settings. 67 healthcare professionals across six case studies in Scotland (n = 3) and England (n = 3) and 32 patients with systemic vasculitis were interviewed. Services faced significant challenges in prescribing and delivering high-cost drugs to manage systemic vasculitis: balancing accountability versus bureaucracy, and tensions between different specialties looking after vasculitis patients when implementing access to high-cost drugs via multi-disciplinary networks. There was significant variation in how services delivered intravenous treatments: 10%(5/51) used inpatient beds; 35% (18/51) accessed another specialty unit or shared a daycase facility; 65% (33/51) used their own specialty daycase unit. Average wait time for urgent IV treatment was 2.67 days (range 1-10 days). 18% of services had waiting times >7 days, and of those 67% accessed intravenous treatments via another daycase facility. Specific challenges in accessing daycase facilities included availability of slots and staff, particularly in shared units, due to competition with other services and limited awareness of the importance of timely treatment for systemic vasculitis. This could impact on timing and treatment decisions e.g., prolonged steroid prescriptions. Staff training, competencies and governance to deliver cytotoxic drugs was problematic, particularly for smaller services, and 70% of services said national training modules would be helpful. Oncology units could provide workarounds but daycase nurses with vasculitis knowledge were a valuable source of advice and support for patients attending for treatments, identifying medical issues and arranging assessment if required. Conclusion There is significant variation in access to intravenous treatment for systemic vasculitis. Healthcare organisations should ensure timely access to urgent intravenous treatment for systemic vasculitis within 7 days and appropriately trained staff. National training modules for non-cancer chemotherapy could facilitate equitable access to training. Where treatment is delivered via other units, greater awareness of systemic vasculitis would help provision of information and support for patients. Disclosure W. James: None. A. Nicoll: None. L. Locock: None. L. Harper: None. M. Little: None. N. Basu: None. R.J. Hollick: None.