The sale was under a 10b5-1 plan established in Feb 2014. Dr. Or continues to own 184K shares of ENTA, which is about $6.5M worth at the current market price.
Naturally, I would prefer that insiders not do any selling at all; however, the CEO and CSO have 10b5-1 plans, so they will presumably continue to sell modest amounts of stock on a regular basis if the share price exceeds the threshold specified in their respective plans.