The FDA issued final guidance for developers of drugs to treat severely debilitating or life-threatening hematologic disorders (SDLTHDs), such as hemophilia and sickle cell disease.

Commissioner Scott Gottlieb noted the guidance is intended to streamline the development of pharmaceuticals used to treat patients with SDLTHDs other than cancer, while protecting patients’ safety and avoiding the unnecessary use of research animals.

In vitro and/or in vivo proof-of-concept studies should be conducted prior to clinical trials to evaluate the mode of action and effects of the drug related to its intended therapeutic effect, the agency says.

An assessment of the drug’s potential effect on vital organs—such as the respiratory, cardiovascular and central nervous systems—should be completed before beginning clinical trials. “Detailed clinical observations following dosing and appropriate electrocardiographic measurements in nonrodents are generally considered sufficient,” the agency says, noting that stand-alone safety pharmacology studies aren’t needed.