On 26 May 2026, the European Food Safety Authority (EFSA) published a scientific opinion on the renewal of authorisation for the feed additive 6-phytase (4a23), produced with Komagataella phaffii DSM 25375 and marketed as ENZY PHOSTAR P/L by Kaesler Nutrition GmbH. The additive is intended for all poultry species, weaned piglets, pigs for fattening, sows, and minor porcine species. EFSA concluded that no new evidence raises safety concerns for the target animals, consumers, or the environment under the current conditions of use, and that the additive remains effective as a zootechnical additive (digestibility enhancer).
Document background
The opinion was prepared by EFSA's Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) following an application from Kaesler Nutrition GmbH for renewal of the additive's EU authorisation. The original authorisation was granted under Regulation (EC) No 1831/2003. The document is a scientific assessment, not a regulatory decision; the European Commission and Member States will decide on the formal renewal based on EFSA's findings.
Key findings and trade-offs
EFSA confirmed that the additive's production strain and manufacturing process remain unchanged and that the maximum recommended dose (500 FTU/kg feed) is safe for all target species. No new toxicological or ecotoxicological data triggered a revision of previous safety margins. The opinion also noted that the additive does not pose a risk to users handling it, provided appropriate dust-control measures are in place.
The assessment involves a trade-off between regulatory continuity and the burden of proof: the renewal process requires applicants to submit updated dossiers even when no new risks have emerged, ensuring ongoing oversight but imposing compliance costs on industry. For Kaesler Nutrition, the positive opinion removes uncertainty about market access for ENZY PHOSTAR P/L, a product used to improve phosphorus digestibility and reduce environmental phosphorus excretion from livestock.
Impact on stakeholders
For livestock farmers and feed manufacturers, the renewal maintains access to a well-established enzyme additive that helps lower feed costs by reducing the need for inorganic phosphorus supplementation. For EU consumers, the opinion reaffirms that meat and eggs from animals fed the additive are safe. For regulatory authorities, the opinion provides a science-based justification to continue authorisation without additional restrictions. For Kaesler Nutrition GmbH, the positive assessment supports continued commercialisation of the product in the EU market.
Expected follow-up
The European Commission will now draft a regulation to renew the authorisation of 6-phytase (4a23) for the requested species, following the standard comitology procedure with Member State vote. The current authorisation remains valid until the Commission adopts the renewal act.