Health plans and insurers are not yet turning to biosimilar infliximab as a preferred therapy, according to Gillian Woollett, DPhil, MA, of Avalere. Her new report surveyed publicly available policy about health plans across the nation. The principal finding was that step therapy was commonly used to encourage use of the originator product.
In fact, just one health plan (representing 1% of the 172 million lives covered in this study) supported the use of either Inflectra® or Renflexis® over the reference product Remicade® through step therapy. One plan (2% of the covered lives) allowed the use of either the originator product or Inflectra as a first step.
Four of the 18 plans with publicly available information did not utilize step-therapy rules for any forms of infliximab. However, “10 of the 18 plans (55% of plans, 52% of covered lives) require the use of [Remicade] first, alone or in combination with another DMARD,” stated Dr. Woollett in the report. A total of 81% of the covered lives from these 18 plans were subject to step therapies limiting access to one infliximab product or the other.
On its face, this type of step policy makes a bit of sense. Step therapies are often used alone or part of prior authorization mechanisms to make sure patients try more cost-effective agents first. In rheumatoid arthritis, that may comprise use of nonbiologic drugs before proceeding to a TNF inhibitor and then to another biologic in patients with rheumatoid arthritis. However, there is no proven benefit (or even logic) to offering a biosimilar infliximab after failing Remicade, or vice versa. If there was a significant clinically relevant difference in immunogenicity, this could be an issue, but this also has not been seen in practice. It makes more sense to try another anti-TNF or perhaps even move to an interleukin inhibitor—something with a different (or slightly different) mode of action.
A policy such as this can confuse the issue for patients, whose knowledge of biosimilars seems tenuous, and even providers, some of whom have little experience prescribing them, particularly because of payers’ Remicade-first policies.
The Avalere report provides some support for how payers are arresting utilization of biosimilar infliximab in favor of the originator infliximab product.
Dr. Woollett paints a very different picture for subcutaneously administered filgrastim products. Forty-nine percent of the covered lives (five large plans) had policies favoring Zarxio®, whereas 27% of covered lives were encouraged to use Neupogen® first. For these 18 plans, five (28% of plans, 49% of covered lives) demonstrate a preference for the biosimilar, filgrastim-sndz. Five (28% of plans, 27% of covered lives) demonstrate a preference for the reference filgrastim. Eight plans (44% of plans, 24% of covered lives) do not indicate a preference through formulary design. A further 24% were not subject to any preference.