Nabiximols discontinuation rate in a large population of patients with multiple sclerosis a 18-month multicentre study.
Delta-δ-tetrahydrocannabinol and cannabidiol (THCCBD) oromucosal spray is used as an add-on therapy option for moderate to severe multiple sclerosis (MS) spasticity resistant to other medications. Aims of this study were to provide real-life data on long-term clinical outcomes in a large population of Italian patients treated with THCCBD and to evaluate predictors of THCCBD therapy continuation. This prospective observational multicentre Italian study screened all patients with MS consecutively included in the Agenzia Italiana del Farmaco e-registry at the start of THCCBD treatment (baseline), after 4 weeks (T1), 12±3 weeks (T2), 24±3 weeks (T3), 48±3 weeks (T4) and 72±3 weeks (T5) from baseline. A total of 1845 patients were recruited from 32 MS Italian centres. At T1, 1502 (81.4%) of patients reached a Numerical Rating Scale (NRS) improvement of ≥20%, with an NRS reduction of 26.9% at T1 and of 34.4% at T5. At T5, 725 patients (48.3% of 1502) discontinued treatment with highest discontinuation rate at T2 and T3. Daily number of puffs was generally stable through the observation period. The multivariate analysis showed that higher NRS scores at baseline (OR 2.28, 95% CI 1.15 to 6.36, p<0.01) and higher differences of NRS between T0 and T1 (OR 2.11, 95% CI 1.08 to 8.26, p<0.05) were associated with an increased probability to continue therapy after 18 months. THCCBD effects were sustained for 18 months with a relatively stable number of puffs per day. About 50% of patients abandoned THCCBD therapy for loss of efficacy or adverse events.