Cancer drug sponsors won’t have to do separate studies if they can demonstrate that the weight of evidence shows that a given drug is dangerous to developing babies, the FDA said in a final guidance document.

The 13-page document adopts proposals on fetal toxicity studies originally laid out in the International Council for Harmonization’s S9 Nonclinical Evaluation for Anticancer Pharmaceuticals, but it goes further by offering the kinds of information that regulators might consider for the weight of evidence.

The list includes:

• Reproductive findings in humans, such as when a drug is in a class of pharmaceuticals with extensive, publicly available information on potential reproductive effects;
• Findings from genetically modified animals or models using pharmacologic inhibition;
• Data from a surrogate model, if it’s available and the “target biology in the animal species is relevant”; 
• A review of the existing literature; or
• Use of alternative assays, such as fit-for-purpose in vitro or ex vivo, or nonmammalian in vivo assays.