Ocrevus (ocrelizumab) is a less expensive treatment option for relapsing multiple sclerosis (MS) than subcutaneous interferon beta-1a (Rebif) in the long-run, according to a cost-effectiveness analysis published in the Journal of Medical Economics.
In addition to lower total costs over a 20-year period, the analysis suggested that Ocrevus allows patients to live longer with a better quality of life. The costs also were lower for Ocrevus for each life year lived, also when taking quality of life into consideration.
These findings might inform payers and policymakers as they make decisions about how to reimburse MS therapies, researchers said.
The study, “Cost-effectiveness analysis of ocrelizumab versus subcutaneous interferon beta-1a for the treatment of relapsing multiple sclerosis,” was performed by Analysis Group in collaboration with Ocrevus developer Genentech.
Because Ocrevus has not been available long enough to do a retrospective cost-effectiveness analysis, researchers built a model using data from the two Phase 3 OPERA trials (NCT01247324 and NCT01412333) of relapsing MS, in which the drug was compared to interferon beta-1a. They also used previously published data to supplement information.
The model assumed that patients could be in any of 21 health states. These were made up of relapsing-remitting (RRMS) patients with a disability level of 0–9 using the Expanded Disability Status Scale (EDSS), secondary progressive MS (SPMS) with an EDSS score of 0–9, or death.
In each of the 20-year analyses, patients with RRMS could transition across EDSS scores, progress to SPMS, experience relapses, or die. Patients also could stop treatment, and the rate at which this happened was calculated using dropout rates from the OPERA trials. Patients were assumed untreated if they reached an EDSS score of 7 or beyond.
Out of all relapses, analysts assumed that 21 percent required hospitalization — a statistic based on earlier research.
Researchers used drug costs reported as the Wholesale Acquisition Cost (WAC) from the Micromedex Red Book Online, in which costs are reported by manufacturers. Assuming that patients completely adhere to dosing as described in the respective prescription labels, the annual cost of interferon beta-1a was $86,179, and $65,000 for Ocrevus. All costs were discounted at 3 percent per year and the model was corrected with half a year.
Their findings showed that Ocrevus treatment cost less than interferon beta-1a over the 20-year period: $614,519 compared to $678,341 for interferon. This translated to an estimated total cost savings of $63,822.
Looking at various aspects of cost, it became clear that only administration costs were higher for Ocrevus than for interferon — $1,595 compared to $110 — which was linked to the more costly infusion procedures required for Ocrevus treatment.
Monitoring costs were higher for Rebif because the interferon label recommends complete blood counts and liver function tests at one, three, and six months following treatment start and then periodically. Analysts assumed that no monitoring is recommended for Ocrevus.
Costs related to adverse events and relapses also were lower for Ocrevus, as were costs related to EDSS disease states.
In addition, calculations of life years lived, as well as quality-adjusted life years (QALYs), slightly favored Ocrevus. The QALY is a generic measure of disease burden, taking both the quality and the quantity of life lived into account.
Researchers also simulated different scenarios to test the robustness of their model. For instance, Ocrevus’ cost-effectiveness remained better when they analyzed the situation in a five-year or lifetime perspective.
Nevertheless, they did acknowledge several limitations of the model. First, the analysis did not consider other therapies a patient might start after stopping Ocrevus or Rebif treatment. Also, the model assumes that all patients in a particular disease state have the same likelihood of transitioning — a scenario that is far from clinical reality.
Finally, the probability of transitioning, calculated using data from clinical trials and registries, might not be accurate.
Despite these limitations, researchers argue that the analysis shows that Ocrevus outperforms interferon out of a cost-effectiveness perspective — an insight that might guide payers and healthcare policymakers.