The Nobel Prize in chemistry and new drug development: On the other hand...

The Nobel Prize in Chemistry has been awarded for elegant work on the “handedness” of molecules. The prize went to Henri Kagan and Kenso Soai for their pathfinding work on the creation of isomers – mirror-image versions of the same compound that can exist as either its “left-handed” or “right-handed” version, or isomer. It was an accomplishment never before achieved “other than [by] life itself,” in the words of the Nobel Committee.

The former version of a molecule is often denoted by an ‘S’ for the Latin word ‘sinister,’ meaning ‘left’ – a derivation that we left-handed people find deeply offensive. The term for the right-handed molecule is ‘D,’ for the Latin ‘dexter,’ the root of our word ‘dexterous’…. another distinction that annoys us lefties. Pejorative names aside, this difference matters a great deal in biology: The double helix of DNA coils to the right rather than to the left, every time. By contrast, nature prefers using left-handed molecules when making proteins. (Take that, rightists!) 

These remarkable differences were first noted in the mid-19^th century by Louis Pasteur, in examining crystals that had formed in wine (of course). But nature’s impressive one-handed preference must date to the dawn of life itself. 

The award was given for increasing our understanding of the right- or left- “handedness” of molecules, which are mirror-images of one another. We tried to convey that in this picture of my own hands; their position is intended to suggest the graspiness with which these differences have sometimes been exploited to re-patent old molecules. Photo by Karen Tucker.

The Nobel Committee’s announcement and most media accounts referred to the importance of this work for developing new drugs, if the D-isomer were found to have different favorable effects or toxicities not seen with the S-isomer. But a far more common application of this difference occurs when drugmakers take advantage of an often-gullible U.S. Patent Office by claiming that the left-handed version of a given medication has clinical effects that are meaningfully different from an existing right-handed version of the same compound (or vice-versa, or different from a right-left mixture). To get a new patent, companies generally don’t have to provide any evidence that these biological effects are different at all, or are even there. 

But once a new patent is awarded, a company can assign a new brand name to the new isomer and win monopoly rights to it even if its effects are the same as its cheaper predecessor. That ploy can generate billions of dollars, and it often has. 

The result of this isomer chicanery can be found in the home medicine cabinets of many Americans in the form of the widely used “purple pill” to treat g.i. acid disorders secretions – the widely used products Prilosec and Nexium. As the patent was expiring on the blockbuster Prilosec (generic name: omeprazole), its manufacturer transitioned that product from prescription-only status to over-the-counter. They then marketed the left-handed version of the same molecule as a costly new prescription-only drug, Nexium (as in ‘next’). Its generic name is esomeprazole, with the ‘es’ prefix standing for ‘S,’ denoting the left-handed version of the omeprazole molecule. 

That would be fine if the newly patented left-handed drug were different in its effectiveness or side effect profile. But the overworked, naïve, and overly-agreeable people in the U.S. Patent Office demanded no such evidence – even though patents are supposed to be issued only to inventions that are ‘novel.’ (I wrote about this 22 years ago in Powerful Medicines, p. 225.) 

A more recent example is esketamine, the left-handed or S-version of ketamine. It won FDA approval as a dramatically more expensive new treatment for depression – again without providing compelling evidence that it is meaningfully different from the older, cheaper, off-patent regular ketamine (Rethinking Medications, pp 201-203). 

The research that just won the 2026 Nobel prize in chemistry is breathtakingly elegant, and could have future applications for developing drugs that are more effective, less toxic, or both. But for now when it comes to utilization, cost, and policy, most patients are likelier to encounter the venal distortion of these right-left differences, made legal by patent policies that are too often the mirror-image of rational public policy.

In future posts on drug issues I’ll continue to explore both the dexterous science and its sinister manipulation – in an even-handed way, of course.