On 1 January 2026, Medical Dialogues reported that Dr Reddy’s has disclosed to various stock exchanges that it has received a Complete Response Letter (CRL) from the FDA in relation to its Biologics Licence Application (BLA) for AVT03, biosimilar to Amgen’s Prolia® and Xgeva® (denosumab).
Dr Reddy’s and Alvotech entered into a licence and supply agreement in May 2024 for the commercialisation of AVT03, under which Alvotech develops and manufactures the product and Dr Reddy’s will commercialise it exclusively in the US, and semi-exclusively in the EU and UK.
The CRL follows a pre-licence inspection of Alvotech’s Reykjavik manufacturing facility. The CRL did not identify any other deficiencies with the BLA. Inspection of the same facility also resulted in a CRL issued in November 2025 for Alvotech’s BLA for AVT05, biosimilar to J&J’s Simponi® (golimumab).
Alvotech/Dr Reddy’s BLA for AVT03 was accepted for review by the FDA in March 2025. In November 2025, Amgen filed BPCIA litigation in the US District Court for the District of New Jersey against Dr Reddy’s/Alvotech alleging infringement of 31 US patents covering denosumab, pharmaceutical compositions of denosumab, methods of manufacturing therapeutic proteins like denosumab, and denosumab products.
AVT03 was approved in Europe in November 2025. Alvotech has semi-exclusive commercialisation agreements for European markets with both STADA (June 2024) and Dr Reddy’s (May 2024) in relation to AVT03. STADA will market AVT03 as Kefdensis® (referencing Prolia®) and Zvogra® (referencing Xgeva®), while Dr. Reddy’s will market AVT03 as Acvybra® (referencing Prolia®) and Xbonzy® (referencing Xgeva®).