The shortage of these drugs has resulted in the emergence of “gray markets” in which the drugs are exchanged repeatedly between various suppliers before they reach the end-user. Typically, gray markets are socially beneficial, moving goods toward consumers with the strongest demand. But in this case, prescription drug gray markets seem unsavory and will likely soon be the subject of new government regulation. However, drug makers can circumvent this intervention while, at the same time, capturing some consumer surplus that they currently lose to distributors.
The shortage / The FDA historically has defined a “drug shortage” as “a situation in which the total supply of all clinically interchangeable versions of an FDA-regulated drug is inadequate to meet the current or projected demand at the patient level.” That definition is probably not satisfactory to economists, but we can appreciate its meaning: there’s a sudden and dramatic decrease in supply at the drug’s customary price.
These shortages affect less than 1 percent of the approximately 40,000 ethical drugs on the market. Interestingly, the vast majority of the affected drugs are generic versions. This seems counterintuitive; one would expect that once a patent has expired and generic makers can begin production, there would be ample supply at the customary price.
The two independent sources for the shortage data are the University of Utah’s Drug Information Service (DIS), which manages the American Society of Health-System Pharmacies (ASHP), and the FDA Center for Drug Evaluation and Research’s Drug Shortage Program. The FDA data report lower numbers than the DIS, which is in part a product of how the two organizations define a “drug shortage.” But the difference is also partly attributable to the sources that the two agencies use for their data: DIS’s information comes from care providers who judge whether a drug is in shortage, whereas the FDA uses drug manufacturers’ data.
As shown in Table 1, both data sets exhibit the same general pattern over the past 10 years: the annual number of new shortages increased steadily in the latter 2000s, then eased in the early 2010s. However, according to the DIS data, the number of shortages remains troublingly elevated as compared to the mid 2000s, while the FDA data show a dramatically lower number of shortages in recent years.
A trend worth special attention is the percentage of drugs in shortage that are “sterile injectables.” These often are older, off-patent drugs produced by generic manufacturers. They include cancer drugs, anesthetics for surgery, drugs for emergency medicine, and electrolytes for intravenous feeding. As a percentage of new ethical drug shortages, sterile injectables have remained in the 70 to 80 percent range from 2010 through 2013, with 2014 being the first year to drop below 70 percent (at 68.2 percent).
Elasticities and investment / In most markets, the volume and seriousness of product shortages depend on the extent to which demand and supply of the product respond to changes in price. In microeconomic theory, these responses are referred to as price elasticities; products that experience sharp changes in supply or demand as a result of a price change are price-elastic; products that don’t experience much change are price-inelastic.
Understandably, the demand for prescription drugs is fairly inelastic. These goods are typically “medically necessary” and in many cases there are few effective substitutes. Besides, most patients have health care insurance, hence consumer demand for these drugs (and most health care services and products) is largely unaffected by price changes. Furthermore, hospitals and physicians generally prescribe medication based on its effectiveness for the patient, which is unrelated to the price paid for the drug.
On the supply side, there is also a lack of responsiveness to changes in price, at least in the short run. Pharmaceutical production often requires expensive, specialized equipment for specific drugs, and manufacturers are required to adhere to “current good manufacturing processes” that require time to implement because they are complex. Sometimes a manufacturing line can be reconfigured relatively quickly to produce a different drug that’s in the same class—say, transitioning from one type of ACE inhibitor to another. But that’s not the case if the reconfiguration involves two different drug classes—say, shifting from an antibiotic to an anesthetic. Moreover, pharmaceutical raw materials are not always readily available and require validation by manufacturers and FDA regulatory approvals. Furthermore, prescription drugs have a limited shelf life; as a result, manufacturers’ inventories are often kept low, reflecting more of a just-in-time manufacturing philosophy.