VOX  CEPR Policy Portal

Many observers believe that pharmaceutical firms prefer to invest in drugs to treat diseases rather than vaccines. This column presents an economic rationale for why such a pattern may emerge for diseases like HIV/AIDS. The population risk of such diseases resembles a Zipf distribution, which makes the shape of the demand curve for a drug more conducive to revenue extraction than for a vaccine. Based on revenue calibrations using US data on HIV risk, the revenue from a drug is about four times greater.