04. Utilization and Tolerability of Anifrolumab-fnia in Home Infusion Patients

Background: Systemic lupus erythematosus (SLE) is the most common form of lupus, a chronic autoimmune disorder where the immune system attacks healthy tissues and cells causing inflammation and damage across various organs, including the skin, joints, kidneys, and brain. Anifrolumab-fnia (Saphnelo) was approved by the FDA in 2021 for the treatment of SLE, as an addition to standard therapy. The American College of Rheumatology Lupus Clinical Practice will not be be release until spring of 2023. However, the 2023 update to the European Alliance of Associations for Rheumatology (EULAR) guidelines recommend belimumab and anifrolumab as first line therapy in severe cases of SLE with non-major organ development.

Anifrolumab-fnia is a monoclonal antibody that targets and inhibits the type I interferon receptor (IFNAR). Type I interferons are overproduced in SLE, driving inflammation and immune dysregulation. By blocking this receptor, anifrolumab-fnia reduces in inflammatory responses, thereby alleviated SLE symptoms and limiting organ damage Clinical trials have demonstrated that administering anifrolumab-fnia, at 300 mg every four weeks effectively lowers overall lupus disease activity, improves skin and join symptoms, and allows for reduced steroid use.
Unlike existing SLE treatments such as hydroxychloroquine, systemic glucocorticosteroids, and belimumab, which may leave residual symptoms, anifrolumab-fnia offers a distinct advantage by targeting all type I interferon receptors without requiring a loading dose, reconstitution, or lab monitoring. This makes it a promising option for enhancing SLE management.

Purpose: The primary objective of this study is to assess the usage of anifrolumab-fnia for SLE in home infusion patients. The secondary objective is to assess patient tolerabiity of anifrolumab-fnia.

Methods: This will be a retrospective, multi-center study including patients who were initiated on anifrolumab-fnia over a period of 3 years. Data collection will include prior medication history, usage of steroids, concomitant medications for SLE, improvements of symptoms once on anifrolumab-fnia, and tolerability. Treatment improvement will be assessed by specific labs (CRP levels, CBC). Data will be collected through electronic medical records. This research was determined to be IRB exempt.

Results: A total of 116 patients met the inclusion criteria and were evaluated for this retrospective analysis. The study cohort comprised 5 (4.3%) males and 111 (95.6%) females, with an average age of 46 years (range 18-78). (Table 1) Of the 116 patients, 40 (34.5%) discontinued anifrolumab therapy, while 76 (65.5%) remained active. Discontinuation reasons are detailed in Figure 2, with the most common factors being cost and non-compliance, highlighting financial burden and adherence issues as key contributors. Clinical concerns accounted for 21.9% of discontinuations, including adverse reactions (7.3%), contraindications (2.4%), and lack of improvement (2.2%). Other notable reasons included changes in pharmacy providers and patient relocation.

Figure 3 illustrates prior medications in patients who eventually discontinued anifrolumab. Of these, 27 (32.9%) had previously been treated with belimumab, indicating that many patients transitioned from another biologic therapy before starting anifrolumab. Immunosuppressive agents were also commonly used, including azathioprine (17.1%), methotrexate (14.6%), and mycophenolate (12.2%). Less frequently used agents included cyclophosphamide, Orencia, and Humira, each reported in 2 patients (2.4%).

Figure 4 summarizes concomitant medications taken while on anifrolumab. Hydroxychloroquine was the most frequently used concomitant medication (59 patients, 46.5%), reflecting its standard role in lupus management. Prednisone or other corticosteroids were used by 28 patients (22%). Immunosuppressive agents were prescribed in 31.4% of cases, with mycophenolate (17.3%) being the most common, followed by azathioprine (5.5%), leflunomide (5.5%), and methotrexate (3.1%).

Discussion: The findings suggest that accessibility improvements and strategies to enhance patient adherence could help reduce discontinuation rates. Addressing provider continuity may also support therapy maintenance. Additionally, the high proportion of patients transitioning from belimumab and other immunosuppressants may suggest that anifrolumab is being prescribed for individuals with more severe or refractory lupus.

The frequent use of hydroxychloroquine and corticosteroids alongside anifrolumab underscores the complexity of disease management and the need for continued efforts to achieve steroid-sparing outcomes. The high number of patients who tried belimumab and subsequently discontinued anifrolumab suggests that some patients may have been resistant to multiple biologic treatments. Patients previously treated with azathioprine, methotrexate, or mycophenolate likely had more severe disease forms. Those coming off cyclophosphamide may have experienced significant disease activity warranting biologic escalation, but discontinuation could reflect issues such as adverse reactions or lack of improvement.

Efforts to improve accessibility and patient adherence could potentially reduce discontinuation rates.

Conclusions: In conclusion, this study contributes to the limited data available on anifrolumab in the home infusion setting. The low discontinuation rate due to ADRs indicates that anifrolumab is generally well-tolerated, in a diverse patient population of patients. The concomitant medications studied on active patients on anifrolumab support SLE remission guidelines (oral corticosteroid (OCS) dose of ≤5 mg per day, stable maintenance doses of immunosuppressants, no use of restricted medicines, and no premature discontinuation of anifrolumab).