The US FDA has issued a draft guidance for industry entitled ‘Considerations for Demonstrating Interchangeability with a Reference Product: Update.’ This draft guidance describes considerations regarding a switching study or studies intended to support a demonstration that a biological product is interchangeable with a reference product.

FDA issued the guidance for industry ‘Considerations in Demonstrating Interchangeability With a Reference Product’ (May 2019) (Interchangeability Guidance) before receiving and reviewing any biologics license applications (BLAs) submitted under section 351(k) of the Public Health Service Act (PHS Act) for a proposed interchangeable biosimilar.

Since publication of the Interchangeability Guidance, experience has shown that for the products approved as biosimilars to date, the risk in terms of safety or diminished efficacy is insignificant following single or multiple switches between a reference product and a biosimilar product.

Accordingly, FDA’s scientific approach to when a switching study or studies may be needed to support a demonstration of interchangeability has evolved.