OBJECTIVES : Biosimilars are an emerging market in the United States (US), with eight biosimilars accounting for over $400 billion in market share. However, it is still trailing that of the European Union, where over 25 biosimilars have been approved. The goal of this review was to examine biosimilar landscape and identify potential barriers and opportunities for the emerging biosimilar market in the US.

METHODS : A comprehensive literature review was conducted in PubMed, Google Scholar, and grey literature. The studies on the topics of biosimilar development and market uptake. Search strategy included a combination of keywords, such as “biosimilars”, “biologic”, “guidelines”, “costs”, “regulatory”, “legislation”, “opportunities”, “challenges”, and “barriers”. Studies reporting the impact on US biosimilar market were retained for full text review and key findings were abstracted. We did not review editorials, opinions, commentaries, or perspective articles without empirical evidence.

RESULTS : We classified the identified studies into three categories based on the factor affecting biosimilar market entry and penetration—stakeholder perspective, economics, and regulatory and legislative factors. Stakeholder perspectives included biosimilar knowledge and safety concerns with substitution. Economic factors included legal costs, financial incentives to payers, and reimbursement issues. Regulatory and legislative factors included Food and Drug Administration robust biosimilar framework, extrapolation to other therapeutic areas, anti-biosimilar lobbying by states, and the “patent dance”. Uniquely, each of these factors are challenging, yet may present an opportunity for expansion of biosimilars within the US. Additionally, these factors were found to be interlinked, maneuvering and shaping the biosimilar market.

CONCLUSIONS : Emerging biosimilars in the US are governed by an interplay of a multitude of factors. None of the studies we identified comprehensively explored biosimilar market access in light of clinical, economic, legislative, and regulatory data. Although biosimilars have promising growth potential, winning with biosimilars requires understanding of the intricacies of specified factors.