Scientists have long understood that cancers are as individual as the patients in which they develop and proliferate. We still classify cancers in different groups depending on tissue origin, morphology and other factors, but genomic studies have revealed that on a cellular and molecular level, cancer cells can be very individual within a group. We also know from antibody-based therapies that the patient’s immune system can be used to fight cancer cells. Antibody-based therapies have been, and newly developed antibodies will continue to be, successful in the treatment of cancer. But the idea of directly activating the patient’s humoral immune response against tumour cells promises a lasting vaccine-like response. Individualising this immune response, tailored to unique (mutated) proteins produced by patients’ own cancer cells, opens a new avenue of vaccine-like cancer therapies. Individualised mRNA cancer vaccines may be the answer to the treatment of previously untreatable or unresponsive cancers.
Unfortunately, individualised treatments are not something that drug developers, manufacturers and regulatory authorities are used to dealing with. The MHRA draft guideline on individualised mRNA cancer immunotherapies indicates that regulatory authorities are willing to discuss new ideas and QC-concepts required to industrialise the individualisation of mRNA therapies.
The publication of the MHRA’s draft regulatory guidance on individualised mRNA cancer immunotherapies marks more than just a technical milestone in regulatory science. It addresses the fundamental challenges to the way medicines have been conceptualised, manufactured and approved for over a century. Once, the industry relied on the predictability of mass-produced drugs designed, tested and delivered in homogeneous batches. Now, individualised drugs demand a regulatory framework for therapies that are, by definition, unique to every patient. Traditional drug development, however, is built upon scale. A single molecule, discovered and refined, undergoes years of preclinical and clinical testing across populations to establish safety and efficacy before being manufactured at scale. Regulatory oversight centres on batch integrity, ensuring that each vial, tablet or syringe from a given lot is chemically and functionally identical. Quality assurance is grounded in reproducibility over the complete lifecycle of the product. Although individualised therapies break with this paradigm, most elements of the production will still have to be reproducible and traceable to ensure that the quality in terms of identity, purity and quantity is designed into the product and, more crucially, that each single batch is received by the intended patient. A guideline should address these points.
