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It was Heraclitus of Ephesus (535-475 BC) who first proclaimed that the world exists in a constant flow of change. This is even more apparent when it comes to science and technology. While the developers and proprietors of consumer-targeted products and gadgets know this well, in drug development the bottleneck of regulatory approval ensures that the flow is linear and only towards improvement.
A drug will not be approved unless it is better – or, in some cases, safer – than existing ones. As a result, while we witness very rapid changes in the nature of drugs being discovered and those under development, there is much less variability in the marketplace.
New Therapeutic Techniques
The majority of marketed therapeutics are small molecule-based, followed by biologics such as monoclonal antibodies (mAbs). Therapeutic modalities such as cell and gene therapies still represent a relatively insignificant fraction of the global drug market. Mesenchymal stem cells (MSCs) were first described by Arnold Caplan in the early 1990s and have proven to be a popular therapeutic modality, and the subject of at least 346 clinical trials (1,2). However, so far, there have only been two conditional marketing authorisations for Prochymal©.
The advancement of an entirely new and very different therapeutic technology is a complex undertaking. A key complication is the necessary optimisation of all parameters of technology and all associated products, to achieve sufficient efficacy for clinical benefit and, ultimately, marketing authorisation. Such a goal is not achievable overnight, but is, and must be, the result of systematic experimentation; a lengthy continuum of change and evolution.
The development of mAb therapeutics was a lengthy progression from murine, to chimeric, humanised and fully human, and continues in full flow toward better glycosylation, bi- and multi-specific antibodies, alternative antibody scaffolds, and armed antibodies that carry therapeutic payloads, such as anti-cancer agents. Cell-based therapies must follow the same path of progress and improvement.
http://www.samedanltd.com/magazine/12/issue/219/article/3851
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