The main purpose of this legislation, known as the "Cutting Copays Act," is to make changes to the Medicare Part D program, specifically aimed at reducing the out-of-pocket costs for low-income individuals who need prescription medications. The goal is to ease the financial burden on these individuals by adjusting the cost-sharing requirements for their medications. Key provisions of the act include adjustments to the copayment amounts that low-income individuals must pay for their prescriptions.