Real World Data Highlights Impact of Ocrelizumab Availability on Recently Switched Multiple Sclerosis Patient Characteristics and Switching Patterns

Background: Retrospective patient chart review fielded by an independent market intelligence agency which specializes in analysing the disease-modifying therapy (DMT) market, including new start and switching treatment decisions, in multiple sclerosis (MS).

Objectives: Analyze DMT switching patient characteristics and switching patterns pre- and post-launch of ocrelizumab, approved for relapsing forms of MS and first drug approved for primary progressive MS (PPMS).

Methods: Fielded just prior to the FDA approval of ocrelizumab, a retrospective patient chart review of 1,002 MS patients who switched DMTs within the previous three months was conducted with 197 US neurologists. The same study will be fielded in February 2018, allowing for a comparison of pre- and post-market impact.

Results: Prior to ocrelizumab availability, 79% and 3% of recently switched MS patients were diagnosed with relapsing remitting MS (RRMS) and PPMS, respectively.  The mean Expanded Disability Status Scale (EDSS) score was 2.2 and 4.5 for RRMS and PPMS patients, respectively. Between the two most recent visits, 37% of audited patients had a relapse, 30% increased T2 lesions, 18% enlarging T2 lesions, 17% increased T1 lesions, 22% increased Gd-enhancing lesions, and 11% brain atrophy. 71% of patients were switched to their second DMT and 16% to a third DMT. Most patients were switched from an interferon DMT (43%) or a glatiramer acetate agent (29%) to an oral DMT (44%).  21% of patients specifically requested the initiated DMT. When efficacy was the primary driver of the switch (40% of patients), neurologists were specifically targeting relapse reduction in more than one-third of patients. Among efficacy-related switched, 29% of patients were switched to a monoclonal antibody DMT (versus 17% overall).  21% of the recently switched patients were classified by their neurologists as being “very likely” candidates for ocrelizumab. These potential ocrelizumab candidates had higher EDSS and Rankin scores, were more likely to have a progressive form of MS, and were more likely to be on a later line of therapy.

Conclusions: With strong ocrelizumab RRMS and PPMS uptake and the paradigm shifting towards earlier use of more aggressive therapy and promptly switching nonresponders, the authors hypothesize that, following 10 months of ocrelizumab availability, 1) more switching will come from first-line oral DMTs, 2) PPMS will make up a greater share of recently switched patients, and 3) ocrelizumab-treated patients will be more likely to be diagnosed with RRMS and have lower EDSS scores then pre-launch expectations suggested.