Patients and doctors still haven't fully invested in the use of biosimilars, despite a steady rise in the cost of biologics, shows a new report by Harvard researchers.
The study, by Seoyoung C. Kim, M.D., of Brigham and Women's Hospital in Boston, is based on an analysis of a nationwide commercial healthcare plan of 14 million patients. Researchers found that while the cost of TNF inhibitor infliximab biosimilars remain steady at about $8,464 per patient, less than 1 percent of patients use biosimilars compared to comparable biologics, such as adalimumab (Humira, AbbVie), which comprises of nearly 50 percent of all TNF biologic use.
Dr. Kim and colleagues focused on the utilization of the five originator TNF inhibitor products and infliximab biosimilars Renflexis (infliximab-abda) and Inflectra (infliximab-dyyb), both of which were on the market at the time of the study from Q1 2016 and Q1 2019. Two other infliximab biosimilars Ixifi (infliximab-qbtx) and Avsola (infliximab-axxq) have also been approved by the U.S. Food and Drug Administration.
They analyzed outpatient dispensing or intravenous administrations of TNF inhibitors between January 1, 2016 and March 31, 2019 comparing the use of five originator TNF inhibitors and the infliximab biosimilars among patients who received at least one prescription or infusion.
The analysis included approximately 1.1 million TNF inhibitor prescriptions or infusions that were dispensed to 95,906 patients. Adalimumab was the most commonly dispensed TNF biologic accounting for 45 percent of all TNF inhibitors prescribed in the first quarter of 2016 and 49.4 percent of all TNF inhibitors prescribed in the first quarter of 2019. It was followed by etanercept, branded infliximab, certolizumab and golimumab.
Biosimilars to infliximab (infliximab-dyyb and infliximab-abda) had slow starts with only 0.1 percent of all TNF inhibitors used in the second quarter of 2017 and 0.9% in the first quarter of 2019.
- The cost of biologics gradually increased from 2016 to 2019. For example, infliximab cost an average of $8,442 in the first quarter of 2016 and by first quarter 2019, health insurance companies were paying an average of $10,578 for each patient.
- Adalimumab cost an average of $7,283 in the first quarter of 2016, but by first quarter 2019, it practically doubled to an average of $13,740.
- Certolizumab cost an average of $7,012 in 2016 Q1 and by 2019 Q1, it was an average of $10,597.
- Golimumab cost cost an average of $6,889 in 2016 Q1 and by 2019 Q1, it was an average of $10,178.
- Etanercept cost an average of $6,228 in 2016 Q1 and by 2019 Q1, it was an average of $11,647.
- By comparison, the infliximab biosimilar cost an average of $8,322 in the second quarter of 2017, compared to an average of $8,464 in 2019 Q1. The amount rose to an average of $10,112 in the second quarter of 2018 and fell by Q1 2019 which may be due to the availability of unique HCPCS billing codes which are used by biosimilar manufacturers to set competitive rates.
"We observed less than a 1 percent uptake of the infliximab biosimilar. This finding may have been partly attributable to an early lack of savings in insurance-paid cost or patient copayment for biosimilar infliximab versus originator TNF inhibitors," researchers wrote.
Cost savings that have been reported in European markets have not materialized here in the U.S., researchers reported. For example, Denmark experienced 64 percent discount when a mandatory nationwide non-medical switch from originator to an infliximab biosimilar was instituted.
"These findings suggest that current cost savings from infliximab biosimilars in the US alone are insufficient to promote their widespread use and that comparable savings to those achieved in some European companies may not be possible without systemic reform of the U.S. pharmaceutical market," the authors wrote.