Biosimilars are products that are highly similar to medicines containing biologic products such as proteins or antibodies. The MHRA’s draft guidance aims to provide developers of biosimilars with clear requirements to market and sell biosimilar products in the UK at the end of the Brexit transition period when EU regulatory provisions will no longer directly apply. The UK government has already said that it will use the opportunity to depart from EU rules and regulations, where necessary, to implement a regulatory system that is robust and responsive.
Every medicinal product requires a marketing authorisation (MA) before it can be marketed in the UK and the EU. Some MAs can be granted by individual member states, whereas others must be obtained centrally across the EU from the European Medicines Agency (EMA). The EMA is responsible for evaluating the majority of applications to market biosimilar medicines in the EU.
When the Brexit transition period ends on 31 December 2020, the MHRA will replace the EMA as the body responsible for evaluating MA applications for biosimilar products in the UK. The MHRA plans to finalise its guidance prior to this date so that it can be implemented from 1 January 2021.
Broadly speaking, developers of biosimilars must show the regulatory authorities through comprehensive scientific comparative studies that their product is highly similar to the original approved biologic product, known as the ‘reference’ medicine. They must also show the authorities that there are no clinically meaningful differences between their biosimilar and the reference medicine in terms of safety, quality and efficacy. The draft guidance published by the MHRA is based on guidelines that have already been prepared by the Committee for Medicinal Products for Human Use (CHMP), a body of regulators within the EMA, for the assessment and the authorisation of biosimilars in the EU.
Importantly, however, the MHRA’s draft guidance expressly states that it has departed from the CHMP guidelines in some respects, in light of “the scientific and regulatory experience” since the licensing of the first biosimilar product in the EU in 2006. It refers to a September 2020 review of biosimilar applications in the EU which concluded that “extensive comparative analytical studies” between the biosimilar and the reference medicine, combined with an “abbreviated clinical package”, should be sufficient to assess biosimilarity in most cases, with the latter focussed on assessing metabolism, clearance, safety and immunogenicity of the biosimilar product in the body.
The UK MHRA’s support for the use of in-depth knowledge of the reference product and laboratory analytical techniques to predict clinical comparability of biosimilars could reduce the need for developers to conduct head-to-head efficacy trials between biosimilars and reference medicines.