Medicare prescription drug plan sponsors need to make their enrollee materials compliant with the recently passed Inflation Reduction Act before the next sign-up period, according to a notice the Centers for Medicare and Medicaid Services issued Tuesday.

The Inflation Reduction Act, which President Joe Biden enacted last month, includes provisions designed to reduce prescription drug costs for Medicare beneficiaries, such as limiting cost-sharing for insulin to $35 and eliminating out-of-pocket spending for vaccines under Part D next year .

Health insurance companies must revise Medicare Advantage and Part D materials to reflect the new law prior to the upcoming open enrollment period, which begins Oct. 15 and ends Dec. 7. Insurers must notify enrollees about the insulin and vaccine policies by Sept. 30 and distribute revised benefit summaries and update their websites by Oct. 15, CMS directs in the memorandum.

CMS also advises insurance companies to review all beneficiary communications—not just those highlighted in the memo—to ensure they comply with the new law.

If hard copies of materials can’t be updated before they’re sent to enrollees, insurers should send correction notices by Nov. 15, the memo says. Insurers can combine updates into a consolidated mailing. Plans do not have to resubmit documents already provided to CMS and the agency won’t take compliance action to enforce the changes outlined in the memo, the agency wrote.