Swiss pharmaceutical company Roche Group said Monday it has suspended a late-stage trial for a new rheumatoid arthritis and lupus drug after several patients died from infections.

Roche said the drug, ocrelizumab, was developed together with Biogen Idec with headquarters in Cambridge, Massachusetts.

A review found "the safety risk outweighs the benefits observed in these specific patient populations at this time" after detecting "serious and opportunistic infections, some of which were fatal," Basel-based Roche said.

It declined immediately to say how many patients died, where and when.

The company said it was still testing ocrelizumab for patients with relapsing remitting multiple sclerosis

Roche shares were down 0.6 percent at 179.60 Swiss francs ($167.54) on the Zurich exchange.