Implications of the new FDA/CDER immunotoxicology guidance for drugs

Although it has long been recognized that drugs, like other xenobiotics, could have adverse effects on immune function, historically, the assessment of the immunotoxic potential of pharmaceuticals has been undertaken in a haphazard fashion. Typically, studies have been conducted either after adverse effects were observed in clinical trials or if obvious signs of immunotoxicity were seen in nonclinical studies. This situation is changing with the promulgation of new guidances and guidelines by various regulatory agencies, especially in those countries involved in the ICH process. It is anticipated that studies conducted to comply with these regulatory requirements will result in a much better understanding of the immunotoxic potential of pharmaceuticals. In addition, new methods are likely to be developed for detecting drug-induced adverse immune effects. In particular, better methods need to be developed for the prospective identification of drugs which have the potential to induce allergic reactions. In this review, the essential points of the new FDA/CDER guidance document will be discussed, especially with respect to promotion of research into issues such as drug allergy.