682
Personalized Medicine and Orphan Drug Syndrome
There is no satisfactory defi nition of an orphan disease. In the USA it is defi ned as
one that affects <200,000 individuals but this number is less in other countries with
smaller populations. In general, an orphan disease is a condition that affects
<1 person per 10,000 of population. Most of the orphan diseases are genetic in ori-
gin. The common factor between personalized medicine and the orphan drugs is a
small or targeted patient population. There are examples of orphan drugs that are
personalized medicines as well:
- Kalydeco for cystic fi brosis (CF), approved by the FDA in 2012, addresses the
underlying cause of CF rather than the symptoms. It is a targeted therapy for
patients with the specifi c G551D mutation that is found in only 4 % of CF cases
in the US. - Crizotinib (Xalkori), which targets a fusion containing ALK found in 5.5 % of
non-small cell lung cancer patients. - Vemurafi nib (Zelboraf), Dabrafenib (Tafi nlar), and Trametinib (Mekinist) for
targeting BRAF V600E mutation found in 15 % of melanoma patients.
Segmentation of a common disease into subcategories on pharmacogenomic
basis might create a small population for a certain drug – orphan drug syndrome.
Orphan Drug Law in the US and similar laws in European Union, Japan and some
other countries provide fi nancial incentives for the pharmaceutical companies
developing products for orphan diseases. The same could be applied to personalized
medicine. Potential problems in this area, ethical and those related to cost-
effectiveness, remain to be addressed.
Commercial Aspects of Pharmacogenomics
The commercial aspects of personalized medicine that are discussed are based on
considerations of the cost of various technologies that will be used in developed
such medicines. Systematic pharmacoeconomic studies of pharmacogenomics have
not yet been carried out. The economic benefi ts can be predicted on the basis of
current progress made in genomics and will be a sequel of reduced time for R & D
and introduction of the product into the market.
Cost of DNA Testing
DNA tests for identifying an individual is simple and cheap. Commercial laborato-
ries offer DNA testing for paternity and other relationships for as little as $130.
Legal setting raises the costs. There are over DNA 1,200 tests available, mostly for
diagnosis of diseases. The cost varies from $150 to over $1,000 with an average of
$500. The costs are expected to drop in the future as the use increases. Markets for
molecular diagnostics are described in a special report on this topic (Jain 2015b ).
23 Economics of Personalized Medicine