Manufacturers must continue to use their discretion on which line extensions should be subject to inflation-based Medicaid rebates in lieu of guidance from CMS in its recent AMP final rule.

A major regulation that could reshape how the pharmaceutical industry reports drug pricing to the government and pays rebates on Medicaid drugs is slated to be released in final form in 2014. Some Medicaid regulatory experts suggest that CMS could make changes in the final rule that will make it less disruptive to manufacturers’ businesses than they have feared.

CMS’ proposed rule on average manufacturer prices for Medicaid relies on examples given in the Affordable Care Act for its list of “bona fide service fees” that manufacturers should exclude from the AMP calculation, but does not further expand on them. The proposed rule also avoids defining “fair market value” for such fees.