I sold out today, shortest holding ever, only share I ever sold after less than 1 year! 11 days held for a 19% profit.
My thesis broke, a friend alerted me to a $5b deal between Galapagos, a US biotech, and Gilead Science. The deal breaker for me was the news that GLPG have a drug that also treats OA as well as other similar diseases - I believed one of PAR's strongest advantages was that all other drugs under development only treated pain symptoms and not underlying cause, discovering this was not the case meant I lost my conviction in the asymmetry of the risk and so I sold out.
It may well keep rising, and the market may not consider GLPG1972 a threat, but I have learnt the hard way, if my thesis for a business is broken, then get out. I am a little annoyed that I didn't uncover this competitor in my research, but thats offset by the profit I booked in any case.