The US Food and Drug Administration has rejected Celltrion’s submissions for biosimilars to Roche drugs Rituxan and Herceptin.

According to media reports, the company received complete response letters for Herzuma (trastuzumab; CT-P6) and Truxima (rituximab; CT-P10).

Celltrion told BioCentury that the issues relate directly to an earlier warning from the regulator in January outlining GMP violations at its manufacturing plant.

Celltrion also told PharmaTimes that it intends to resubmit the applications "relatively soon" and anticipates gaining approval six months after.

The European Medicines Agency approved Herzuma in February for people with early breast cancer, metastatic breast cancer, or metastatic gastric cancer whose tumours have either HER2 overexpression or HER2 gene amplification, and Truxima early last year the treatment of certain cancers and inflammatory conditions.