The Containment of Supply and Demand

Evidently there is a shortage of cancer drugs in the US right now and instead of a humane response, we are seeing significant price increases. The first rule of free-market economics is that the price of a product is whatever the market will bear. However, when securing a scarce product makes the difference between life and death for the consumer, this rule should be suspended: it is simply immoral for scarcity to influence the price of a life-saving product. What would we say to someone who agreed to rescue another person from a precarious situation, (a fire, drowning, etc.) only upon payment of a significant sum of money?