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.