I'm reading Joeph Stiglitz's work and I have thought, being a future business man and a moral newbie economist, that the better way to treat medical patents as same as other kind of patents is set a top profit related to costs of the production, in monopoly market power. If you want to receive a higher profit you have to reduce costs and reduce a bit less prices. With other kind of patents, out of the health care system, growing companies can have a higher top profit level the first two years for example. This would help that company to invest and get market power. Regarding spillovers, a few contracts 50/50 on profits, after a few years, can improve investigation and development of new techniques or products related to the patent.
I think this answer is less extreme than my first one.