U.K.’s Voluntary Scheme For Branded Medicines, Pricing, And Access (VPAS) Faces A Potential Crisis Two large U.S.-based drug companies - AbbVie and Eli Lilly - have now exited the voluntary drug price agreement, citing the “punitive” system of revenue clawbacks, which has risen to 26.5% of branded sales in 2022. And, AbbVie and Lilly aren’t the only companies complaining about the levies.