personalizedmedicine.bmpSo-called personalized medicine — tailoring treatments to an individual’s genetic traits — is showing great promise, but insurance companies are balking on paying for the very costly medications.

Each treatment typically costs multiple thousands of dollars, and when accepted, the medications add to the already high price of U.S. health insurance.

There’s a summary of the problem in an Mercury News piece, which cites successful products by Silicon Valley companies like Genomic Health (breast-cancer), Genentech (cancer), Cholestech (heart attack/stroke) and Monogram Biosciences (HIV) — all of which are facing challenges getting covered. Finally, there’s private company, XDx, which predicts heart transplant rejections, which we wrote about today, and is seeking new funding.

If it really takes 15 to 20 years for insurance companies accept these medications — as one cited study suggests — it could hamper the personalized health-care start-up boom going on in the valley.