Past research has shown that rare mutations in a gene called SCN9A give some people complete immunity to pain. A handful of pharmaceutical companies are now working to develop drugs to imitate that genetic mutation. Rather than muting pain by reducing inflammation, like ibuprofen and similar drugs do, or by turning on the body’s analgesic properties, such as opiates do, Pfizer Inc. and a few other smaller companies including Xenon Pharmaceuticals Inc. and Convergence Pharmaceuticals Ltd. are working on new methods tied to the SCN9A gene.
Scientists connected the pain-free condition to SCN9A in 2006, after studying families in northern Pakistan with the syndrome. One of those studied was a 10 year old boy who worked as a street performer, entertaining people by walking on hot coals. One researcher wrote in the journal, Nature, “None knew what pain felt like, although the older individuals realized what actions should elicit pain.”
For people with this pain-free condition, inherited mutations in the SCN9A gene block the functioning of the sodium channels called NAV1.7. The experimental drugs also try to block their functioning, or at least diminish their ability to transmit pain.
While the effectiveness of Nav1.7 drugs is still not known, Simon Tate, chief scientific officer of Convergence Pharmaceuticals believes one possible benefit is their potential to be non-addictive. Other drugs on the market today for epilepsy and other diseases block several sodium channels, including Nav1.7 and show “no evidence of addiction,” he says. wsj.com 7/31/13