The "Defending Affordable Prescription Drug Costs Act" is a new chapter added to Title 5 of the General Laws, aimed at prohibiting discriminatory practices against 340B covered entities and their contract pharmacies by health insurers, pharmacy benefit managers, and pharmaceutical manufacturers. The act specifically prohibits these entities from:

1. Establishing lower reimbursement amounts for 340B drugs compared to non-340B drugs based solely on the drug's 340B status.
2. Imposing different fees, chargebacks, adjustments, or conditions on reimbursement based on 340B status.
3. Denying or limiting participation in pharmacy networks based on 340B status.
4. Imposing inconsistent audit requirements related to inventory management systems.
5. Requiring claims-level data identifying 340B drugs as a condition of reimbursement, unless mandated by the Centers for Medicare and Medicaid Services.
6. Requiring a 340B covered entity to reverse, resubmit, or clarify a claim after initial adjudication unless in the normal course of business.
7. Interfering with a 340B covered entity's choice to use a contract pharmacy for drug distribution or dispensing.
8. Including discriminatory provisions in contracts with 340B covered entities.
9. Placing restrictions or additional charges on patients choosing to receive 340B drugs that differ from those applied to non-340B drugs.
10. Excluding 340B covered entities from networks or refusing to contract with them for reasons not applicable to non-340B entities.
11. Imposing any other restrictions not applied to non-340B entities.

The act also restricts pharmaceutical manufacturers from denying, restricting, or interfering with the acquisition or delivery of 340B drugs to contract pharmacies and prohibits them from imposing additional terms not required by federal law.

Additionally, the act mandates that each 340B covered entity submit an annual report detailing their participation in the federal 340B program, including financial data and the impact of savings on community benefits. Violations of this act will be considered violations of chapter 13.1 of title 6 regarding unfair sales practices. The act is set to take effect on October 1, 2025.