I know this is a really old post, but is there any update on this? I can't find anything newer than 2009 via google.

Good question.....

Merck purchased Sirna in 2006 and I don't think researching how to get rid of unwanted hair was on their priority list, as it was for Sirna. If anything, they would be pursuing the oncology track, for obvious reasons They understand how to "silence the genes", but the delivery system is a real challenge. You might want to research the two doctors that discovered how to interfer with the RNA (Craig Mello and Andrew Fire) and see if they are still doing this research: http://www.ip-right.org/Right/rnai

I read an interview with one of the head developers of this. He said the main reason it fell through was due to technological shortcomings. Namely, they couldn't get the siRNA to penetrate into the skin.

However, researchers from Northwestern have just developed a topical delivery method to do just that!...
http://www.northwestern.edu/newscenter/stories/2012/07/skin-disease-treatment.html

I wonder if the people from Sirna will pick up on this new technology and continue with their project!!