Cost-Effectiveness of MS Therapy

The most common disabling neurologic disease among adults 18 to 60 years of age is multiple sclerosis (MS). Disease-modifying therapies (DMTs) are the gold standard of disease management for MS, with the goal of preventing or delaying permanent neurologic disability.

First-line DMTs for MS are fingolimod, subcutaneous (SC) interferon IFN beta (b)-1b, SC IFN b-1a, glatiramer acetate, and intramuscular (IM) IFN b-1a. Adherence, (measured by medication possession ratio [MPR]), to those therapies has been reported as 89.2%, 72.4%, 77.8%, 82.1%, and 79.2%, respectively.

Noting that suboptimal adherence can have a negative impact on patient outcomes, researchers recently conducted a study, supported by Novartis Pharmaceuticals Corporation, to assess the impact of differential adherence on relapse rates and cost-effectiveness of first-line DMTs in MS from the perspective of a commercial payer in the United States. They reported results of their study during a poster session at the Academy of Managed Care Pharmacy 2012 Educational Conference in Cincinnati, Ohio, in October. The poster was titled Cost-Effectiveness of Multiple Sclerosis Treatments: Effects of Adherence.

The analysis utilized a Microsoft^® Excel-based model to estimate the cost-effectiveness of fingolimod compared with other first-line DMTs in patients with relapsing forms of MS. The researchers obtained wholesale acquisition costs (WACs) for all DMTs from Analy$ource^® Online, a web-based pricing tool. Monitoring requirements were based on the product Prescribing Information for each agent; unit monitoring costs were obtained from the 2010 Physicians’ Fee & Coding Guide.

The cost of relapse was based on the cost of managing the relapse and the severity of the relapse. The relative severity of each relapse was obtained from the EVIDENCE (Evidence for Interferon Dose-Response: European North American Comparative Efficacy) trial and was assumed to be the same for all DMT treatments.

Patients were considered adherent if they had an MPR ≥80% over the 12-month period following the second prescription fill. The impact of nonadherence (MPR <80%) on real-world relapse rates was calculated based on published estimates. The estimated relapse rate for nonadherent patients was calculated based on the relapse rate of adherent patients divided by the odds ratio of adherent patients having a relapse.

The cost per relapse avoided was calculated for each of the DMTs over a 2-year time horizon.

Fingolimod was associated with the lowest cost per relapse avoided (90,566), followed by SC IFN b-1b (Extavia^® [interferon beta-1b], $142,268; Betaseron^® [interferon beta-1b], $153,944), SC IFN b-1a ($155,486), glatiramer acetate ($174,097), and IM IFN b-1a ($370,397).

The model inputs with the greatest impact on the results were adjusted relapse rate reduction (relative to placebo) of fingolimod, the WAC of fingolimod, and the average number of relapses in untreated patients with MS. Assuming that all patients on fingolimod had an MPR <80%, the total cost per relapse avoided remains lower than the other DMTs.

Limitations cited by the authors included basing estimates of DMT adherence on data from a single claims database study of a large national pharmacy benefit manager that only measured adherence, not actual relapse, and not incorporating manufacturer discounts and rebates into the cost model.

In summary, the researchers stated, “Adherence has a significant impact on real-world effectiveness in MS, which, in turn, influences cost-effectiveness. Higher rates of adherence among patients treated with fingolimod translate into higher estimated real-world effectiveness in this model. Fingolimod had the lowest cost per relapse avoided in all scenarios, ranging from 0% to 100% of patients adherent to treatment. Clinical efficacy demonstrated in clinical trials and real-world adherence rates due to tolerability must be considered in evaluating the value of MS therapies.”