Medicare covers Keytruda, but the amount you pay depends on which Medicare plan you have and whether your doctor prescribes it in an office or hospital setting

Keytruda (pembrolizumab) is a cancer immunotherapy drug used to treat several types of cancer, including melanoma, non-small cell lung cancer, and head and neck cancers. Medicare Part B covers Keytruda when it is given by injection in a doctor's office or hospital outpatient department. Medicare Part D covers Keytruda as an oral medication if your plan includes it on its formulary — the list of drugs the plan will pay for.

The key difference is where the drug is given. If your oncologist administers Keytruda as an infusion in the office, Part B handles it. If you take a pill form at home, your Part D prescription drug plan handles it. Your out-of-pocket cost will vary based on your specific coverage and deductible status.

Key Takeaways

  • Medicare Part B covers Keytruda infusions given in a doctor's office or hospital outpatient setting, and you typically pay 20% of the cost after meeting your Part B deductible.
  • Medicare Part D covers oral Keytruda if your prescription drug plan includes it on its formulary, and your copay or coinsurance depends on which tier the drug is placed on.
  • Not all Part D plans cover Keytruda, so you will need to check your specific plan's formulary or call your plan to confirm coverage before treatment begins.
  • If Keytruda is not covered by your current plan, you can request a coverage exception from your plan, or you may be able to switch plans during the annual enrollment period.
  • Your oncologist's office can often help you understand your coverage and work with your insurance to reduce delays in starting treatment.

How Medicare Part B covers Keytruda infusions

When Keytruda is given as an intravenous infusion in a doctor's office, hospital outpatient clinic, or infusion center, Medicare Part B pays for the drug itself. You pay 20% of the Medicare-approved amount after you have met your annual Part B deductible (which is $240 in 2024, though this amount changes yearly). The remaining 80% is covered by Medicare.

Part B also covers the administration fee — the cost of the nurse or technician giving you the infusion — under the same 20% coinsurance structure. If you have a Medigap or Medicare Advantage plan, your supplemental coverage may reduce or eliminate your 20% coinsurance, depending on your plan's terms.

Your oncologist's billing office should be able to tell you upfront what your share of the cost will be based on your specific Medicare coverage. It is worth asking them to estimate the cost before your first infusion so you are not surprised at the time of treatment.

How Medicare Part D covers oral Keytruda

If your doctor prescribes Keytruda as an oral tablet to take at home, your Medicare Part D prescription drug plan covers it — but only if the drug is on that plan's formulary. Each Part D plan creates its own list of covered drugs, and not all plans include Keytruda. Some plans may cover it only for certain cancer types or only after you have tried other drugs first.

Your out-of-pocket cost depends on which tier Keytruda is placed on. Specialty drugs like Keytruda are usually on a higher tier, which means you pay a higher copay or coinsurance — often 25% to 33% of the drug's cost. For an expensive drug like Keytruda, this can mean hundreds of dollars per month out of pocket.

You can find out whether your specific Part D plan covers Keytruda by logging into your plan's website, calling the plan's customer service number (on the back of your insurance card), or asking your pharmacy. Your oncologist's office can also check this for you.

What to do if your Part D plan does not cover Keytruda

If Keytruda is not on your plan's formulary, you have several options. The first is to request a coverage exception from your Part D plan. Your doctor submits a letter explaining why Keytruda is medically necessary for your specific condition. The plan then reviews the request and decides whether to cover the drug anyway. This process usually takes a few business days to a week.

A second option is to ask your doctor whether a different drug on your plan's formulary could work for your cancer type. Your oncologist knows which alternatives are available and whether they are appropriate for you.

A third option is to switch to a different Part D plan during the annual enrollment period (October 15 to December 7 each year). You can compare plans on Medicare.gov to find one that covers Keytruda. If you are newly diagnosed with cancer outside the enrollment period, you may be able to make a change due to a life-changing event — contact Medicare at 1-800-MEDICARE to ask.

Your oncologist's office often has experience navigating these coverage issues and may be able to speed up the exception request or suggest which plans are most likely to cover your treatment.

Medicare Advantage plans and Keytruda coverage

If you have a Medicare Advantage plan (Part C), coverage for Keytruda works differently than Original Medicare. Medicare Advantage plans must cover all drugs that Original Medicare Part B and Part D cover, but they can charge different copays and coinsurance amounts, and they may require prior authorization before you start the drug.

Prior authorization means your doctor must get approval from your Medicare Advantage plan before prescribing Keytruda. This adds a step to the process but usually does not delay treatment by more than a few days. Your oncologist's office handles the prior authorization request on your behalf.

Call your Medicare Advantage plan's customer service number to find out your specific copay for Keytruda infusions and whether prior authorization is required. Plans vary widely, so it is worth asking directly rather than assuming.

Cost information programs for Keytruda

If your out-of-pocket cost for Keytruda is very high, the drug's manufacturer, Merck, offers a patient information program. This program can help uninsured or underinsured patients pay for Keytruda. You can learn more by calling 1-855-KEYTRUDA (1-855-539-8783) or visiting the Merck Patient information Program website.

Some nonprofit organizations also offer grants or copay information for cancer patients. Organizations like CancerCare, Patient Advocate Foundation, and the American Cancer Society maintain lists of programs that may help with medication costs. Your oncologist's social worker or financial counselor can also point you toward resources specific to your situation.

These programs do not replace insurance but can help bridge the gap if your Medicare coverage leaves you with a large bill. It is worth exploring them even if you have Medicare, because many programs work alongside insurance rather than instead of it.

Frequently Asked Questions

Will Medicare cover Keytruda if my doctor says it is medically necessary but my plan does not cover it?

Medicare Part B will cover Keytruda infusions regardless of your plan's formulary, as long as your doctor prescribes it in an office or hospital setting. If your Part D plan does not cover oral Keytruda, you can request a coverage exception from your plan, and your doctor can submit medical documentation supporting the request. The plan then decides whether to cover it.

How much will I pay out of pocket for Keytruda under Medicare?

Under Part B infusions, you typically pay 20% of the Medicare-approved cost after your deductible. For Part D oral medication, you pay the copay or coinsurance your plan assigns to the drug, which can range from $100 to $500 or more per month depending on the tier and your plan. Your oncologist's office can give you a more precise estimate based on your coverage.

Can I switch Medicare plans if my current plan does not cover Keytruda?

You can switch Part D plans during the annual enrollment period (October 15 to December 7). If you are newly diagnosed with cancer outside this window, you may be able to make a change due to a may have access to life event — contact Medicare at 1-800-MEDICARE to ask. Your oncologist's office can also help you find plans that cover Keytruda.

Does my Medicare Advantage plan cover Keytruda?

Yes, Medicare Advantage plans must cover all drugs that Original Medicare covers, but they may charge different copays and may require prior authorization. Call your plan's customer service number to find out your specific copay and whether prior authorization is needed before your doctor prescribes it.

What should I do if I cannot afford my Keytruda copay?

Contact Merck's patient information program at 1-855-KEYTRUDA or explore nonprofit copay information programs through CancerCare or the Patient Advocate Foundation. Your oncologist's social worker or financial counselor can also help you find programs that may reduce your out-of-pocket cost.