Washington ? The Food and Drug Administration said Thursday that it will sharply limit access to the anti-diabetes drug Avandia because of concerns about an increased cardiovascular risk associated with the drug.

Patients who are now taking the drug will have to sign an informed consent statement acknowledging that they understand the risks before they will be allowed to continue refilling prescriptions. New patients will not be able to receive the drug unless their doctor certifies that they are unable to control their blood-sugar levels with other medications and that they are unable to take Avandia’s primary competitor, Actos, for medical reasons.

At the same time, the European Medicines Agency said that it will suspend marketing of Avandia, also known by the generic name rosiglitazone, throughout the European Union.