The safety of any medicine such as biosimilar is as dependent as much on the system that supports it as the biological properties of the medicine itself. Part of this system rests as proprietary information within a company, while part rests within healthcare system that uses the product. This raises the question of how and by using which metrics can we measure system safety to ensure system similarity? It is hard showing there’s nothing to worry about, so should similarity between the innovator and the biosimilar systems be standardised? Measuring adverse reaction frequencies indicate harm rather than safety which depends on human performance. Even if we were to rely on spontaneous reports, the delayed onset of adverse reactions and overlapping of therapies hinders causality assessment especially when comparing different products using spontaneous evidence. This makes it even more important that licence holders work with healthcare providers to ensure processes are in place to ensure traceability their products in case they need to demonstrate safe use. Hospital IT (information technology) systems are an essential source for recording and retrieving information about adverse events and suspect medicines. So, it is of concern to find evidence from the Netherlands showing that very low frequencies of recording of brand names and batch numbers for biologicals in pharmacy datasets (1). Thus the presence of multiple IT systems within healthcare that lack integration may be an obstacle to efficient adverse event reporting weakening traceability especially, as has also been shown in the US, many IT systems do not capture drug identifiers other than brand and/or INN. In the US, lack of system integration was cited as a significant reason for not reporting ADEs.
NHS England provide the following guidance about switching to biosimilars ‘Doctors reserve the right to switch a patient’s medicine provided there are appropriate monitoring arrangements in place’. So without adequate arrangements for traceability healthcare professionals could reasonably argue against switching to a biosimilar.
Biosimilar biologicals are entering a market where there is considerable uncertainty about how to manage risk and thus their systems need to be at least of equivalent quality to that of the innovator. Unfortunately, we only use a few metrics for measuring system performance which are not shared publically. Industry associations would be strongly advised to convene a working group to recommend and agree upon system metrics and performance indicators. This means it is even more important to adhere to the high standards of non-clinical and clinical quality criteria for similarity that have been established by WHO, EMA and FDA and continue discussions about how they can be more precisely defined. Meanwhile at all steps of the prescribing and dispensing chain, every feasible form of identifier should be strongly encouraged to aid traceability. Pharmacy software providers need to be engaged so that current IT systems are updated to capture all such identifier information, in particular, batch number. I agree no biosimilar safety concerns have been demonstrated so far from those biosimilars that have been marketed but we must not allow complacency to deter us from striving to improve our systems.
(1) Klein K, Scholl JHG Vermeer NS et al Traceability of Biologics in The Netherlands: An Analysis of Information-Recording Systems in Clinical Practice and Spontaneous ADR Reports Drug Safety February 2016, Volume 39, Issue 2, pp 185-192