A number of people have asked me what is causing the current shortages in certain types of drugs. Here’s what I’ve been able to discern so far:
In general, there are two reasons why shortages might appear in a market. The first is high fixed costs. These include regulatory costs, the costs of converting a manufacturing plant to a new use, or the costs of creating a new factory. Industries with high fixed costs will see temporary shortages after either supply shocks (e.g., a factory goes offline) or demand shocks (e.g., an increase in the population needing a drug). The price mechanism eventually resolves such shortages. The duration of the shortage is related to the size of the fixed costs.
Shortages also appear when something interferes with the price mechanism’s ability to resolve a shortage. The classic example is government price controls (i.e., a binding price ceiling). Such shortages persist as long as the price controls (e.g., rent control) remain in place and binding.
From my study of the current spate of drug shortages, the best accounting for these shortages appears in this publication by the U.S. Department of Health and Human Services: “Economic Analysis of the Causes of Drug Shortages,” Issue Brief, October 2011.
I initially suspected these drug shortages were caused by Medicare’s Part B drug-payment system. Others, including Scott Gottleib and the Wall Street Journal, have made that claim. However, this study and a lengthy discussion with the U.S. Department of Health and Human Services’ assistant secretary for planning and evaluation have persuaded me that not only is Medicare’s Part B drug-payment system not the cause, that system doesn’t even impose binding price controls. Rather, it controls the margins that physicians earn for administering a drug. (If Medicare did impose binding price controls, would we see mark-ups of 650 percent or more for the shortage drugs?)
Rather, the shortages appear to be the result of a number of dynamics in the market for rare drugs: