In the majority of cases, the grant of a patent captures the chemistry and purpose of a drug and locks it away for the given number of years. This is the monopoly given to the manufacturer who will police the drug market and sue anyone who comes too close for infringing the patent. The very act of protection discourages future research to develop the drug for new and different purposes. Yet, in one or two cases, research does go on. Most of the time, this represent unofficial interests where physicians experiment with off-label uses, or there is just a simple change so that, what comes in multiple doses, may be spread out through an extended release capsule. Only in quite rare cases is the research real and sanctioned by the original manufacturer. So it is with Pfizer and its now famous little blue pill. In every way, this pill broke the mold. It was a literal game changer. Under development for one purpose, its accidental power to inspire men is now the stuff of legend. But that left Pfizer with an interesting choice. It had already invested millions to develop a drug to help relieve pulmonary arterial hypertension (PAH). Should it just throw all that money away? Although tempting, given the billions of revenue now flowing into its bank account, Pfizer decided to continue developing the drug for PAH. The result is Revatio, the same basic PDE5 inhibitor applied to the arteries in the chest rather than those leading into the penis. It has become a lifesaver. What is interesting is the change of name. Apparently Pfizer did not think patients would believe in the effectiveness of the drug if it continued under it erectile dysfunction name. A whole new brand identity had to be developed.

In a desire to prove the chemistry is applicable to an ever wider range of conditions, there are now trials underway to test whether it is an effective treatment for cancer, multiple sclerosis, strokes and, somewhat surprisingly, some aspects of mental disability. In all cases, the common feature is the ability of the drug to dilate arteries to improve the circulation of blood throughout the body. One of the consequences of improved circulation is a boost to the body’s immune system. If blood moves only slowly, it is possible for the immune response to drop quite dramatically, say in the area of a tumor. Hence the current trial to determine whether local administration to cancer of the throat will have beneficial results. Apparently, the early results look promising.

There is something faintly strange about the idea of viagra becoming as commonly used as an aspirin. What had once seemed so uniquely particular to the male need seems to have a potential relevance to almost everyone. Given that there are eleven different forms of PDE in the human body, this gives us the prospect there may be eleven different uses for viagra. Perhaps other drugs are always going to be less flexible. A painkiller, for example, really only has one reason to exist (ignoring the abuse for pleasure). Yet who is making this decision? Who decides a drug only has one use? For all we know, the majority of drugs licensed for use for one purpose may actually have multiple purposes. Ah, wait! That is the problem. If one drug could treat multiple diseases and disorders, there would be no need for multiple different drugs and pharmaceutical companies would make less money. Let us leave it that there shall only be the brand and generic viagra. For any other disorder, there must be a new and expensive drug.