Market size of biologicals in Russia in 2014 was 90 billion rubles, per RBC estimates, and biosimilars accounted for approximately 40 billion of that amount. RBC predicts world biosimilar market growth from 1,3 billion USD in 2015 to 30 billion USD in 2020. A number of biosimilar product development programs in the USA has grown twofold in from 2013 to 2016. These observations indicate worldwide increase of interest for biosimilar products development.
This month FDA released a draft guidance on demonstrating interchangeability of biosimilar products. Per current US legislation, a product is called interchangeable if “the biological product may be substituted for the reference product without the intervention of the health care provider who prescribed the reference product”. Applicant should prove that “the risk in terms of safety or diminished efficacy of alternating or switching between use of the biological product and the reference product is not greater than the risk of using the reference product without such alternation or switch”.
Correspondingly, the guidance contains advice on the conduct of switching design studies. In such studies, reference product and test product are switched in the middle of the treatment phase. Study population should be divided into two arms: one arm will be switching between the proposed interchangeable product and the reference product, another arm will receive only reference product.
Clinical pharmacokinetics and pharmacodynamics parameters should be chosen as primary endpoints of the study. The guidance also provides advice on choosing study population, sample size calculation, study analysis and proper route of administration choice. Furthermore, considerations on post-marketing safety monitoring are included in the document.
Draft guidance was published on January 17th, the agency will be receiving comments within 60 days of publication.