Experiences with Comparative Assessment

Experiences with Comparative Assessment

Under Regulation (EC) No. 1107/2009, if an active substance in a plant protection product has been listed as a Candidate for Substitution (CfS), then a comparative assessment (CA) is necessary for product authorisation. At Kerona Scientific’s virtual Dublin Plant Protection Symposium, held in December 2020, Guy Gibson of consultancy service Enhanced Efficacy described his experiences of preparing the CA.
The purpose of CA is to reduce risks by replacing the molecules that are on the list of CfS (Regulation (EU) No 2015/408). The aim is to move towards safer (and by implication newer) molecules, while preventing significant disadvantages to users, ensuring adequate resistance management options are available, and ensuring that options remain for minor uses. As Mr. Gibson noted, of the 77 molecules on the list, many remain agronomically important.
Mr. Gibson stated that it is critical when conducting a CA to use a methodical approach based on the EPPO efficacy guidance document PP 1/271 (3), the latest version of which is “a lot clearer and more logical” than the previous one.
The stepwise approach begins with consideration of the minor uses. EU Member States vary not just in which uses are regarded as minor, but also in the importance of minor uses for the CA: some Member States stop the assessment if there is one minor use, whereas Germany, for example, stops if there are five.
The second step is to consider the resistance risk: if a target pest has a high or medium inherent resistance risk – which is likely for generic products and most CfS – and the candidate is an important part of resistance management, then the CA can stop here.
Hopefully, according to Mr. Gibson, at this point the applicant will have already established that they don’t need to continue, but if they do, the remaining steps involve considering, respectively, the efficacy and use within IPM and the practical and economic disadvantages of substitution.
Mr. Gibson advised the importance of understanding the biology and agronomy of the product, as well as understanding the alternative products and their weaknesses. It is important to focus on the product’s key targets and to tailor the assessment to the particular Member State. It is also a sensible idea to demonstrate the logical worst case – the removal of all candidates for substitution and all products with the same mode of action – which almost always would be disastrous for growers.
In conclusion, Mr. Gibson questioned whether the CA system has actually achieved anything, as in his experience no product has been prevented from gaining authorisation as a result of CA. He believes it’s likely that the system will be revised in the near future so that some CfS will be removed from the market.
The Kerona Scientific Regulatory Team prepares Comparative Assessment evaluations on behalf of our clients for many Member States. If you need assistance with this or other regulatory assessments for plant protection products, please don’t hesitate to contact us at info@kerona.ie