In Reply: Mega-trials for blockbusters are readily feasible. There would be no cost for the government or health care system. Drug production cost to industry (as opposed to sales cost) is negligible. The proposed mandate could easily stipulate that blockbuster manufacturers donate drugs and placebos for such trials. Total cost to the industry would be approximately 1% of their cumulative sales for the product.
Assume a reward mechanism in which a positive result in a trial that takes T years generates a 1-year patent extension. Expected sales with and without the trial are M’ = TS0 + (t + 1)SpC + tSn(1 − C) and M = (T + t)S0, respectively, in which t is the number of remaining years in the original patent after the trial finishes, C is the probability to get a positive result, and Sp, Sn, S0 are average annual sales, if the result is positive, negative, or no trial is performed, respectively. The excess expected sales with the trial (M’ − M) easily exceed the 1% cost, unless both C is low (it is unlikely to get positive results) and Sn is much less than S0 (negative results are devastating for the drug market).