The OIG has issued the latest in a long line of reports comparing Medicare Part B drug average sales prices (ASP) and average manufacturer prices (AMP), this time with a focus on 2013 pricing. By way of background, CMS has statutory authority to lower Part B drug reimbursement when a drug’s ASP exceeds its AMP or widely available market price (WAMP) by a threshold, currently set at 5%. In April 2013, CMS began exercising its payment substitution authority, but it applies the policy only to certain codes with complete AMP data, and when the ASP for the code exceeds the 5% threshold in two consecutive quarters or three of the previous four quarters. The OIG notes that 15 drug codes were subject to reimbursement reductions under this policy on the basis of data from 2013, which resulted in $13 million in Medicare savings from the fourth quarter of 2013 through the third quarter of 2014. If CMS had expanded its price substitution criteria to include drug codes with complete AMP data in a single quarter or certain codes with partial AMP data, the OIG estimates that CMS could have generated almost $6 million in additional savings. While recognizing CMS’s “cautious approach to price substitutions,” the OIG expressed its view “that CMS can achieve a better balance between safeguarding access to drugs and ensuring that Medicare and its beneficiaries do not overpay for drugs with ASPs that exceed the AMPs by the threshold percentage.” The OIG therefore recommends that CMS consider pursuing regulations to expand the price substitution policy to include at least some additional drug code. CMS continues to oppose such an expansion until there is more experience with the policy.