The Canadian drug maker has asked its outgoing CEO, J. Michael Pearson, to cooperate with a U.S. Senate investigation into drug pricing. Pearson failed to appear for a deposition, but *should* appear at an April 27th hearing. Valeant, who built its business buying older drugs and raising their prices – not a popular business model these days – faces three federal probes into its business practices. This isn’t the first time we’ve heard about drug pricing and the U.S. Senate (remember Turing Pharmaceuticals?) And, it won’t be the last time either.