Typically biologics including biosimilars, are used to treat long term and complex conditions such as cancer, rheumatoid arthritis, psoriasis, Crohn’s disease and growth disorders. Worldwide, over 650 biologics have transformed the lives of over 350 million patients suffering from more than 100 diseases.² 

As a result of their complexity, biological medicines including biosimilars are considerably more expensive to develop and manufacture than conventional medicines. This can make it difficult for the NHS to afford these medicines and can limit patients' access to them.²³ 

By definition, biosimilars are required to have the same amino acid sequence, as the reference products and to demonstrate high purity, and highly similar analytical and functional properties, pharmacokinetics / pharmacodynamics (PK/PD), clinical efficacy (potency) and safety, including immunogenicity.^1,3,17

The European Commission (EC) has clearly expressed its confidence in the quality and consistency of biosimilars. In their 2013 consensus information document 'What you need to know about biosimilars' the EC states that “biosimilar medicinal products have been used safely in clinical practice in the European Union since 2006 and their market share has been growing at different rates across both EU member states and product categories.”¹⁷

The regulatory process for biosimilar medicines is fundamentally different than for generic products which require very limited  clinical development.  In the case of biosimilar medicines, the European Commission issues specific guidelines for each product which specify the procedures, including appropriate clinical trials, to be performed  in seeking regulatory approval of the product.  The main part of the evaluation is a detailed head to head comparison of the biosimilar medicine with its reference medicine to show there is no clinically significant differences between them. The size and duration of the clinical trials is set after a rigorous scientific advice process with the European Medicines Agency. The biosimilar pathway does not need to demonstrate safety and efficacy in each indication as this is done by reference to the originator product which has already satisfied these requirements. ^6,16

Biosimilars are approved via stringent regulatory pathways so that they may be launched following loss of exclusivity of their originator reference products.^{4,5,11,12,13,14.} The scientific review within EMA is carried out by the Committee for Medicinal Products for Human Use (CHMP), who take advice from the Biosimilar Medicinal Products working party. The UK medicines regulator MHRA, plays a leading role within CHMP and provides UK experts to carry out scientific assessment and be part of the decision making process.  The scientific and regulatory principles for demonstrating that biosimilars have no clinically meaningful differences to their reference product build on those used for assessing changes in the manufacturing process of a given biologic.^8,9,10 These comparability principles have been in place for more than 25 years to address manufacturing changes and have been demonstrated to work.

Since 2006, biosimilars have been used effectively in clinical practice in the UK and other European countries where they are already making an impact in terms of cost-savings and patient access.⁷

Biosimilars are approved by regulators across the world, including the EU, only if they have demonstrated comparability to the originator product in terms of safety, efficacy and quality through an extensive and iterative comparability exercise, based on strict guidelines set by the authorities.^{4,5,11,12,13,14}  Regulators such as EMA and FDA will only approve biosimilars for which companies provide information which allows them to conclude that there are no clinically meaningful differences between the reference product and the biosimilar.^3,4,5

The use of biosimilar medicines offers the opportunity for increased access to these important medicines and by creating competition, reducing cost.²⁰ Competition also provides an incentive for originator companies to develop new biological medicines; and biosimilars themselves maybe associated with additional patient support services.

For example, data based on 2010 usage of human growth hormone (hGH) at The North Central London Formulary and Medicines Management Group at University College London Hospitals NHS Trust suggests, annual cost savings in excess of £200,000 per annum are possible from a single centre if all patients were switched from originator hGH to biosimilar hGH.^15,21 Savings generated through biosimilars can be reallocated in the same disease area to help fund access to recent innovative products or help fund access in other disease areas.¹⁹

The cost saving due to competition from biosimilar medicines and the resultant reduction in cost per Quality Adjusted Life Year (QALY)²⁴ may lead to biosimilar medicines being approved by Health Technology Appraisal agencies when the pricing of the equivalent originator product was found not to be cost-effective for example, NICE approval of biosimilar infliximab in Ankylosing Spondilitis in February 2016.²⁵

There is thus scope for biosimilar medicines not just to save the NHS money which can be made available to fund other treatments but also to make specific medicines available to patients within the NHS which might otherwise not be approved for use. 

Biosimilars will usually form part of a NICE multiple technology appraisal (MTA) alongside their reference products, in the indication under consideration.⁶ The Department of Health has confirmed that a technology appraisal remit referred to NICE enables NICE to decide to apply the same remit, and the resulting guidance, to relevant licensed biosimilar products which subsequently appear on the market.¹⁸