The Price and Market Share Evolution of the Original Biologics and Their Biosimilars in Finland

Background Biological drugs are generally expensive and produce a continuously growing share of drug costs. Yet they are essential in the treatment of many chronic diseases. Biosimilars, clinically equivalent to biological originator products, are expected to restrain drug costs in the biological market. Objective This study aimed to examine the impact of the biosimilar market entry on the prices of the reference products in outpatient care in Finland, investigate the impact of biosimilar market entries on price competition among biological medicinal products, and examine how the prices and market shares of outpatient biosimilars have developed in Finland during 2009–2020. Methods This retrospective register study applied data from IQVIA covering national community pharmacy wholesale data between 1 January, 2009, and 31 August, 2020, for somatropin, epoetin, filgrastim, follitropin, insulin glargine, insulin lispro, etanercept, pegfilgrastim, adalimumab, teriparatide, and enoxaparin biosimilars and their reference products, in addition to two relevant insulin products. We determined the monthly wholesale amounts in defined daily doses and wholesale weighted average prices (excluding value-added tax) per defined daily dose for each product. We analyzed the evolution of the price and market shares. We performed a linear segmented regression analysis to examine the impact of the market entry of biosimilars on the prices of reference products. Results The prices of the reference products mainly decreased after the biosimilar entered the market. If the reference product price was not reduced, it was no longer reimbursable after evaluation under the Health Insurance Act, leading to marginal market shares. The changes in the prices of biosimilars were not as remarkable as the changes in the prices of reference products after the biosimilar market entry. For most active substances, biosimilar prices were stable or decreased. The utilization of biosimilars varied widely between different active substances at the end of the observation period. Conclusions Changes in pricing policy and the public reimbursement scheme related to the market entry of biosimilars were the main reasons for the decrease in the prices of reference products. Therefore, biosimilars did not generate genuine price competition between biological products. In many of the drug groups examined, the market shares of biosimilars have growth potential in the future.