Pfizer has received a US FDA complete response letter (CRL) for its proposed version of Roche’s breast cancer monoclonal antibody Herceptin (trastuzumab).

Pfizer announced its biologics license application (BLA) for PF-05280014 has been turned down by the US Food and Drug Administration (FDA), with the agency highlighting the need for additional technical information in the CRL.

The requested information does not relate to safety or clinical data, Pfizer said in a release.

The news comes less than a year after Pfizer received a CRL in response to its proposed version of Amgen’s anaemia drug Epogen (epoetin alpha). On that occasion, issues at Pfizer’s potential manufacturing site in McPherson, Kansas was cited as the reason for the regulatory thumbs down.

However, Pfizer’s manufacturing network was not to blame in the case of PF-05280014, spokesperson Thomas Biegi told BioProcess Insider.

“The areas identified in the CRL do not relate to any issues pertaining to our manufacturing facilities.”

He was unable to comment on how or from where the trastuzumab bisoimilar is made.

Pfizer has one of the largest biosimilar portfolios after acquiring a number of candidates through the $17bn acquisition of Hospira back in September 2015, including the first monoclonal antibody (mAb) biosimilar to be approved and launched in the US, Inflectra (infliximab).

Celltrion

Inflectra was co-developed with South Korean drugmaker Celltrion which manufacturers the biosimilar from its facility in Songdo, Incheon.

The site was hit with an FDA warning letter earlier this year which Celltrion said did not affect its ability to manufacture and supply the Inflectra.

However, the warning was a contributing factor in the FDA’s decision to issue a CRL to Celltrion for its own proposed trastuzumab biosimilar, and a CRL for its version of Roche’s drug Rituxan (rituximab). Both biosimilars, if approved, will be marketed in the US and Canada by Israeli drugmaker Teva Pharmaceutical Industries.