Off-Adherence Keeping (OAK) observational study: intentional off-adherence immunomodulatory multiple sclerosis treatment

Aims: To evaluate how improved treatment adherence with a lower-frequency regimen/treatment of intramuscular (IM) IFNβ-1a impacts therapeutic effectiveness in relapsing-remitting multiple sclerosis (MS) patients switching from a higher-frequency injectable regimen/treatment. Patients & methods: Italian patients with relapsing-remitting MS and prior poor adherence to high-frequency injectable treatments (n = 181) were followed for 24 months after starting IM IFNβ-1a. Results: During the study, 97.4% of patients were treatment adherent; 22.1% of patients reported a relapse. The estimated probability of remaining relapse-free after 2 years was 78%. A high dropout rate (52.5%) led to small sample size and reduced statistical power. Conclusion: Intramuscular IFNβ-1a treatment was associated with high adherence and a low relapse rate. Unfortunately, low patient retention limited the generalizability of these findings. Plain language summary Prior research suggests that taking the drug IFNβ-1a through less frequent muscle injections enables more patients to adhere to their prescription than taking other medications. This study included 181 Italian patients with relapsing-remitting multiple sclerosis (MS) who historically did not take medication as often as prescribed. Relapses of MS were counted among patients treated with muscle injections of IFNβ-1a for 2 years; 97.4% of patients followed their prescription and 22.1% experienced a relapse. From these data, 78% of patients were estimated not to experience a relapse during 2 years of IFNβ-1a muscle injections. However, an unusually high number of patients (52.5%) left the study within 2 years, which makes it difficult to draw firm conclusions.