The FDA's latest quarterly report from its Adverse Event Reporting System has spotlighted a number of drugs with a potential safety issue or that have had new safety information attributed to them between January and March of this year.

According to the list, the US regulator is looking at incidents of liver failure in patients treated with Pfizer's new kidney cancer drug Sutent (sunitinib), and is also investigating gastrointestinal perforation among users of Wyeth and Progenics' opioid-induced constipation treatment Relistor (methylnaltrexone).

Appearing on the list does not mean that the FDA "has identified a causal relationship between the drug and the listed risk", but that there is a potential safety issue. The list also includes products that have had new safety information added to the labelling, including Rocephin (ceftriaxone) which in June had hemolytic anaemia added to the warnings section, and alpha interferon products which last month saw the addition of pulmonary hypertension to the warnings.