New Medicare Rule Forces Coverage for All Autoimmune Drugs, Limits Prior Authorization to Once Per Year Starting 2027

The Patient Access to Autoimmune Treatments Act, or PAAT Act, is a big deal for anyone relying on Medicare Part D to manage long-term chronic conditions like lupus, rheumatoid arthritis, or hemophilia. Starting in 2027, this bill mandates a crucial change: private insurance companies offering Part D plans must cover every drug specifically used to treat an autoimmune disease, hemophilia, or Von Willebrand disease. They can’t just pick and choose which ones make it onto their formulary anymore.

Cutting the Red Tape for Chronic Care

Beyond mandatory coverage, the PAAT Act takes aim at one of the biggest headaches in healthcare: prior authorization. If you have a chronic illness, you know the drill—your doctor prescribes a necessary drug, but the insurance company makes you jump through hoops every few months just to prove you still need it. This bill largely ends that bureaucratic cycle for these specific conditions. As of 2027, Part D plans generally cannot require prior authorization for these specialized drugs more than once every 12 months. Think of the time saved for both patients and doctors, who currently spend hours every month fighting for medication that’s clearly necessary for a non-curable, long-term condition. For someone managing a severe autoimmune flare-up, this means far fewer delays in getting essential treatment.

The Fine Print: Where Plans Can Still Demand Approval

While the 12-month limit is a huge win for patient stability, the bill includes a few carve-outs where plans can still require more frequent authorization. They can bypass the rule if the drug is typically prescribed for less than a year, or if it falls into certain restricted categories, like controlled substances (opioids, benzodiazepines, etc.). They also keep the right to require more frequent authorization for drugs that the FDA requires special safety monitoring for—those under a Risk Evaluation and Mitigation Strategy (REMS). These exceptions are important because they allow plans to maintain necessary oversight for drugs with higher safety risks or abuse potential, but they also give plan sponsors a small window to potentially push back on the annual limit. We’ll need to watch how broadly they interpret these exceptions.

Who Pays for the Mandatory Coverage?

This legislation is fantastic news for Medicare beneficiaries with these conditions—it guarantees access and drastically reduces administrative friction. However, it’s important to look at the cost side. By mandating that Part D plans cover all drugs for these specific diseases, the bill removes a key tool insurers use to manage costs: negotiating coverage based on price and efficacy. This means the financial burden on plan sponsors (the private insurance companies) will increase, as they must now cover potentially expensive specialty drugs without the ability to exclude them. While patients gain better access, these higher mandatory costs could translate into higher premiums for all Part D enrollees or increased costs for taxpayers subsidizing the Medicare program. It’s the classic trade-off: improved patient access often comes with a higher price tag for the system overall.