Study: Step Therapy Contributes to Biosimilar Utilization

Study authors measured savings, conversions to biosimilars, and payer policies for 3 originator brands

Using commercial and public payer data, investigators observed that payer utilization management policies such as step therapy contributed to a sizeable movement toward biosimilar use, according to a poster presentation at AMCP 2021.

“Payers equipped with proactive utilization management strategies for oncology biosimilars were able to capitalize on early utilization shifts to the less expensive biosimilar products,” the authors concluded.

They conducted a retrospective claims analysis for patients with cancer enrolled in commercial and Medicare plans between June 2019 and June 2020. They evaluated the transition to biosimilars from 3 originator products Avastin (bevacizumab), Herceptin (trastuzumab), and Rituxan (rituximab).

The authors of the study also found that, in some cases, physicians were ahead of the curve in prescribing biosimilars and switching patients from originator products to biosimilars, meaning payer coverage preferences did not force them.

Additionally, physicians in private practices were twice as likely to independently switch patients to biosimilars than their counterparts in outpatient hospitals (279 vs 131 switches, respectively, for 5374 prior authorizations).

The study also included a model of savings that could be achieved from biosimilar use based on the utilization and pricing data included. For example, use of originator bevacizumab was associated with an extra $35.6 million in spending compared with use of bevacizumab biosimilars, based on overall costs of 20,076 claims.

The comparable excess spending for trastuzumab originator was $11.7 million for 25,511 claims and $19.9 million for rituximab originator based on 9275 claims.

However, they cautioned that “true savings” could not be determined because variable rebate arrangements between payers and manufacturers made it challenging to calculate.

The study evaluated formulary policies across 16 commercial and 12 Medicaid Advantage plans, and investigators said 30% of those plans had policies that preferred biosimilars, 4% of them had non-preferred coverage, meaning originator biologics had to be used first, and 66% covered biosimilars and originators equally, or “on par.”

Biosimilar utilization actually surpassed the use of innovator brands by the first quarter of 2020 (51%), roughly half a year after the beginning of the study period.

Reference

Fowler A, Borgert R, Polson M, et al. The emergence of therapeutic oncology biosimilars: payer’s perspective. Presented at: AMCP 2021; April 12-16, 2021. Accessed April 15, 2021. https://amcpannual2021.pathable.co/organizations/AETMfk4CdeFgWTR4v