Evidence-based practice in times of drug shortage.

Shortage of oncology drugs is a particularly complicated issue because there are usually limited therapeutic options. Moreover, oncology practice may employ medications for supportive indications which differ from their main usage. This means shortage of oncology drugs is not usually addressed by the major drug shortage guidelines. We have previously shown that, during a shortage crisis, it is possible to make a recommendation on the use of an expired drug supply based on a reasonable estimate of its safety and efficacy. Here, we would like to share further examples on how to deduce potential therapeutic alternatives based on pharmacokinetic and pharmacodynamic principles in the absence of direct clinical evidence in the literature.