Eligibility and implementation of disease-modifying therapy for primary progressive multiple sclerosis in a UK cohort.

BACKGROUND: As disease-modifying therapies become approved for primary progressive multiple sclerosis (PPMS), services must be aligned in readiness. METHODS: In this paper we use population and clinic-based data to estimate eligibility rates for ocrelizumab, and the extent of additional service requirements necessary to ensure its widespread introduction in PPMS. RESULTS: Overall population estimates for the incidence and prevalence of people with PPMS who are eligible for ocrelizumab are 1.6 and 4.2 per 100,000 respectively. The majority (87%) of incident cases of PPMS satisfied clinical eligibility criteria for ocrelizumab but lacked radiological evidence of disease activity due to a historical tendency not to routinely monitor using MRI in this group. The majority of prevalent patients did not satisfy clinical eligibility criteria for ocrelizumab, mainly because of advanced disease duration or disability. CONCLUSIONS: These findings illustrate the fact that there has been a tendency for people with PPMS not to receive routine clinical and radiological monitoring. Additional planning or resources will be required to facilitate contemporary disease re-evaluation and surveillance at a population level.