CSL (ASX:CSL) and Vifor Fresenius Medical Care Renal Pharma said the European Commission revoked the marketing authorization for the Tavneos drug following a recommendation from the European Medicine Agency's Committee for Medicinal Products for Human Use (CHMP), according to a Thursday statement.

Tavneos was developed as a treatment for adults with the main forms of ANCA-associated vasculitis, a potentially life-threatening disease where the immune system mistakenly attacks the body's own blood vessels.

The marketing authorization was revoked due to concerns related to data handling in a phase 3 trial before approval was granted, with the CHMP concluding that a positive benefit-risk balance for the drug could no longer be established.

"While we are disappointed by the decision, we respect the outcome of the regulatory process and are committed to implementing it in full," CSL and Vifor Fresenius said.

Tavneos will no longer be available for prescribing in the European Union and European Economic Area countries.

CSL's shares were down 1% in recent Friday trade.