[Safety and efficacy of off-label use of biologic therapies in patients with inflammatory rheumatic diseases refractory to standard of care therapy : Data from a nationwide German registry (GRAID2)].

BACKGROUND: The German Registry of Autoimmune Diseases 2 (GRAID2) is a retrospective, non-interventional, multicenter registry study collecting data from patients with inflammatory, mainly rheumatic diseases refractory to standard of care therapy and treated with an off-label biologic therapy. The retrospective documentation comprised case history, diagnosis, course of disease (including safety and global efficacy). The objective was to evaluate the global clinical outcome and safety of off-label biologic therapy in clinical practice.

RESULTS: Data from 311 patients with an overall observation period of 338.5 patient-years were collected. The mean patients age was 47.8 years with 56.9% females. The most frequently documented diagnoses comprised rejection prophylaxis/therapy after renal transplantation (NTX, 18.3%), ANCA-vasculitides (17.4%), systemic lupus erythematosus (SLE, 10.3%), autoinflammatory fever syndromes (8.4%), autoimmune myositis (7.4%) and pemphigus (5.8%). Documented biologic therapies included rituximab (RTX, 70.1%), tocilizumab (TCZ, 9.3%), infliximab (IFX, 7.1%), anakinra (ANK, 5.5%), adalimumab (ADA, 3.5%), etanercept (ETA, 2.3%) and certolizumab (CTZ, 0.6%). After initiation of off-label biologic treatment, tolerability was assessed by the physicians as "very good"/"good" in 95.5%. Altogether, 275 adverse events were documented and of these, 104 were classified as serious adverse events and occurred in 62 patients. In 19 of these patients severe infections (30.6%) were documented, resulting in a rate of 5.6 severe infections per 100 patient years. A total of six deaths were documented, while five of these cases were rated as not related to the biologics treatment. Notably, the use of RTX in patients with small vessel vasculitides and of TCZ in patients with large vessel vasculitides prior to their approval support their relevance in clinical management of patients with severe diseases.

CONCLUSION: The results of this registry together with data of GRAID1 provide evidence that use of off-label biologic therapies in patients with inflammatory rheumatic diseases refractory to conventional treatment did not result in any new safety signal already known for these compounds or subsequently shown by clinical trials in certain entities.