Saturday, December 19, 2009

Not All Drugs Are the Same After All

New York Times article "Not All Drugs Are the Same After All" (December 18th, 2009) offers no economic scrutiny to the complex issue of pharmaceuticals.

Let me start by saying I’m a fan of generic drugs. They save Americans billions of dollars each year and give us access to wonderful drugs at affordable prices. I’ve recommended generics in this column many times and use them myself when possible.

The author goes on to speak on the nature of generics and how they may be inferior to the real thing. What the article does not note is two interesting ways in which generics, chemically-equivalent entities, and brand-name drugs interact.

Monopolies are inefficient, and create deadweight loss. Society grants monopolies to pharmaceutical companies to induce them to research and create new products, which create social benefit, both when the monopoly exists and when the patent runs out; competition from generics runs profit down to zero on a drug and society alone gets the full benefit of the new drug. Traditionally, there is a tradeoff between protracting the life of a patent, which encourages research and development, and shortening the life of a patent, which increases social gain for the drugs that are created. Society balances the positive externalities of research with negative externalities of monopoly.

Therefore, as it is unclear whether or not we are at an efficient patent life of twenty years, it is further unclear whether or not generics are "saving" consumers money off drugs that never exist--harming their welfare. However, elasticity of supply increases as time lengthens--after a matter of years, possibly before the patent ends, a drug can face competition from chemically-equivalent compounds. Compounds that are similar, and free-ride off a drug's preexistent research and development, but are different enough that they do not fall under a patent.

If this is the case, then a pharmaceutical firm might see monopoly profits for a matter of years, let's say seven, at which point chemically-equivalent companies compete and drive down profits for the next thirteen, at which time profits are driven down to zero. It may be the case that shortening a patent life increases profits. Were a patent life ten years, then it is possible chemically-equivalent companies would not find their thirteen years of limited competition to be profitable enough to enter an industry, and a pharmaceutical company would gain ten years of monopoly profit, rather than seven, at which point its profits would go to zero.  This scenario is depicted graphically below (click to enlarge).

Additionally, we note that generics may not save certain Americans money. Let us say that, as the article notes, generic drugs are inferior to their brand-name counterparts. Then it may be possible competition for generics makes prices increase, rather than decrease. The reason this is possible is if there exists a heterogeneous population, for which there are inelastic demanders and elastic demanders. Before generic competition elastic demanders are setting the price of a drug, and their quantity is worth a price tradeoff for the firm. When generics are introduced, elastic demanders shift to generics, while inelastic demanders are now the marginal consumers, at which point it is profit maximizing for a pharmaceutical company to raise the price of a good. It is apropos to note that profits will unambiguously decrease for the firm, as quantity will be reduced more than price is increased (otherwise a profit-maximizing monopoly would have reduced price earlier.)  This is depicted graphically below (click to enlarge).


  1. The graphics are much easier to read using the new enlargement tool.

  2. Thank you Gladys! Corrections surmises that figures can often be helpful in understanding our implicit model, especially as we eschew mathematics in our articles save when it is unavoidable. However, it is difficult for Corrections to gauge the comprehensibility of figures and is always looking for feedback.