A proposed rule issued by CMS on September 3, 2010 would withdraw certain provisions of the July 17, 2007 Medicaid average manufacturer price (AMP) final rule, along with the October 7, 2008 final rule defining "Multiple Source Drug." CMS explains that the withdrawal is being proposed in light of retail pharmacies’ legal challenges to the definition of AMP and the multiple source drug provisions, and the passage of health care reform amendments which have effectively superseded the AMP provisions. For more information, see the summary on our sister blog, Life Sciences Legal Update.