Salix did the right thing to stay in compliance with their mission.
Around Oct 2011 Salix was having problems with a Colazal subcontractor, and with two generic versions of Balsalazide Disodium on the market they were not too concerned about shifting their focus to Giazo (an improved version of Colazal). Due to all of the negative input they received (letters, e-mails, phone calls), they realized that a lot of patients do not improve on the generic versions, so they re-focused back on Colazal.
Colazal is back; and in a few months Giazo will also be available, which is supposed to be an improved version of Colazal requiring less pills.