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The assumption that some “in vivo” genotoxins can damage DNA at any exposure level, and therefore that any level can represent a risk, led to a conservative stance being proposed in terms of quality assessment. It was stipulated that a justification must be provided in relation to the manufacturing process that clearly explained why, for that specific process, the presence of genotoxic impurities was “unavoidable.” The position paper also stated that, wherever possible, alternative routes that avoid genotoxic residues should be used and that an applicant was obliged to update the manufacturing process should a safer alternative process be available. If, after these steps had been taken, a risk remained, it was suggested residual levels should be reduced to the level that was “as low as technically feasible.” It is interesting to reflect on recent issues relating to contamination of sartans (most notably valsartan [4]) where similar language to that within this preliminary position paper has been used with calls for “nitrosamine free” sartans being requested by some authorities. This is perhaps not entirely unreasonable for the sartans, given that one route to a particular sartan can bring nitrosamine risk and another manufacturing process (or indeed another sartan) can be free from nitrosamine risk.