I'm thinking that they make much more money if they save lives.
Have you read about the Vioxx case?
Because of the patent laws drug companies concentrate on making small changes to old drugs and sell them as new drugs. Sometimes this is as “harmless” as overstating the efficacy of drugs by commissioning many trials and only publishing the favourable ones. (Yes that’s legal and common practice) Other times it means hiding the side effects of drugs and dealing with the legal repercussions later, if and when the they become known.
The system is explicitly constituted to prioritise profit over human life and well being. Why should we be surprised at the outcome?