These could make it longer for them to achieve FDA approval andÂ cost their sponsors much more money. The recommendations include longer studies in humans, larger safety databases, and more postmarket studies, reports Bloomberg News.Â Also included in the document isÂ guidance on assessing the toxicity of the drug used to coat the stent, both on its own and as part of the complete product. And it has draft recommendations for engineering tests, biocompatibility tests, and animal studies to assess the device's overall safety. The guidance was put together by both CDRH and CDER. A public workshop to gather comments about the draft guidance will be announced shortly.