Viagra’s hidden story

As a convincing example of “disease mongering” [2] by the pharmaceutical industry, Moynihan (4 Jan 2003, 45-47) has analysed the way female sexual dysfunction has been made into a “new” disease. In the same issue (p. 9), news item detailed how Viagra could become a providential preventive treatment for one of the main concerns of half of humanity (at the very least) – male impotence. One might wonder, however, whether Viagra itself is not a perfect example of the increasing tendency of larger companies to make blockbusters from trite chemical entities.

Twenty years ago, I participated in the development of an alpha-blocker, actually a simple me-too: as we were very impressed by the sexual reactions of the young male volunteers included in the phase I studies, it was a joke for us to predict that the registration of a product like this one to treat impotence would certainly lead to an impressive commercial success. The obstacle, of course, was that of potential toxicity… Then, as it was pharmacologically banal that a number of drugs had genuine effects on the male erectile function, any rigorous analysis of sildenafil should have focussed on two crucial questions: 1) is there any evidence that this drug is more efficient than any other product known to have similar effects? 2) is there any evidence that the potential safety problems have been reasonably controlled?

Pfizer provided no answer to the first question, since evidence of efficacy for Viagra was given by placebo-controlled studies: this was correct from a regulatory point of view (since, for the above mentioned reasons, there was no “reference” drug), but represented a sheer perversion from a scientific point of view since everybody knew that a number of drugs had similar pharmacological properties.

Concerning safety and having regard to the number of severe hazards reported after Viagra was marketed, it may be interesting to recall that when this compound was developed, Pfizer was making an enormous fuss about tenidap, an anti-arthritic compound, which, quite early in its development, was massively presented as a fantastic potential blockbuster. Yet, once reaching the registration phase, tenidap was rejected by most regulatory bodies with unusual promptness, precisely because of unresolved safety questions (SCRIP 10-14 May 1996: 22). At the same time, Pfizer received a severe warning letter from the FDA because of repeated failures in reporting serious hazards of its drugs (SCRIP 21 May 1996: 11). These two convergent precedents patently do nothing to reassure us about the reliability of Viagra’s manufacturer regarding the process of safety assessment. Recent information about the fallacies of the benefit/risk assessment of doxazosin (18 Jan 2003, p. 170), another drug marketed by Pfizer, is consistent with these remarks.

Lack of new drugs is reaching crisis point (18 Jan 2003: 119), and this is explained by analysts as the tendency of giant companies resulting from mergers to concentrate on blockbusters. As is well-known, merging does not stimulate creativity, but gives an unprecedented financial power for commercial promotion. Viagra could be the typical example of the way intensive marketing allows big companies to make people believe that the moon is made of green cheese and to give substance to the idea that new chemical entities of problematic benefit/risk ratio represent far-reaching achievements in therapeutics. This policy of mystification is an alternative to the recent recommendation [3] of The Lancet that given the current crisis in drug discovery, pharmaceutical companies should “invest preferentially in the creative minds in their laboratories” (instead of investing in their legal staff) : investing in the creative minds in the reps might not be such a bad idea either – as exemplified by Pfizer’s impressive success story…