Novartis group Sandoz has decided not to pursue US submission of a biosimilar version of Roche's Rituxan/Mabthera, after a request from regulators for more data.

Back in May the firm revealed that its biosimilar rituximab had received a complete response letter from the US Food and Drug Association, but stressed at the time that it "stands behind the robust body of evidence included in the regulatory submission”.

However, following an evaluation of the FDA’s request for additional information to complement the filing, Sandoz said it would not be pushing forward with its application, instead focusing on progressing its biosimilar pipeline “in areas of greatest unmet access needs”.

"We are disappointed to have to make this decision and stand behind the safety, efficacy and quality of our medicine, which met the stringent criteria for approval in the European Union, Switzerland, Japan, New Zealand and Australia,” said Stefan Hendriks, global head of Biopharmaceutical at Sandoz.

“Given the breadth of our biosimilar pipeline, we believe we should now focus on opportunities in the US and around the world where we can best meet rapidly evolving patient and healthcare system needs."

MabThera/Rituxan pulls in sales of more than $7 billion a year across its indications, which include the treatment of rheumatoid arthritis and non-Hodgkin's lymphoma.