Two men can begin the same one-minute cancer injection on the same day and still end up with very different Medicare bills. A missed enrollment choice from years earlier may determine who pays and who does not.
This post may contain links from our sponsors and affiliates, and Flywheel Publishing may receive compensation for actions taken through them.
Imagine two 70-year-old cancer patients starting identical treatment. Their doctors recommend Keytruda Qlex, a skin injection that takes about one minute to give. Merck's list price for each three-week dose is $12,272.
Both men have Original Medicare. One also has Medigap Plan G, which pays his Part B coinsurance after he meets the deductible. The other never bought supplemental coverage, so he would generally owe 20% of Medicare's approved cost each time, with no yearly ceiling on his expenses.
Merck (NYSE:MRK | MRK Price Prediction) said Keytruda Qlex generated $830 million in sales in Q3 2026. The treatment is becoming more common, but the two Medicare bills could look nothing alike.
The $12,272 Sticker Price Is Not the Medicare Bill
Merck's list price for the three-week dose is $12,272 before any discounts. Medicare pays its own approved amount for drugs administered by doctors, and that payment depends on the drug's billing code. Qlex now has a permanent code. On the Q3 earnings call, Merck oncology chief Jannie Oosthuizen said, “Since we received the permanent J-code on April 1, it has been a really positive trajectory.” Coinsurance is based on Medicare's approved amount, so applying 20% to the list price would give the wrong figure. Keytruda Qlex was not included among the drugs chosen for Medicare price negotiations set to begin in 2028.
How Original Medicare Pays
Part B usually covers medically necessary cancer drugs given in a doctor's office, clinic or hospital outpatient department. After the $283 Part B deductible for 2026 is met, the patient typically pays 20% of the Medicare-approved amount. Over a full year on a three-week schedule, that works out to about 17 injections. Each one brings its own 20% charge, and the surrounding office visits, scans and lab work can also trigger coinsurance.
Original Medicare does not have an annual out-of-pocket cap. One limit does apply to most hospital outpatient services: a single copayment generally cannot exceed the Part A inpatient deductible, which is $1,736 in 2026. That still does not cap total yearly spending, so where the treatment is delivered can matter a great deal.
One Treatment, Three Very Different Outcomes
| Coverage (2026) | Deductible he pays | His share of each shot | Annual cap on Part A/B costs | Prior authorization |
|---|---|---|---|---|
| Original Medicare alone | $283 | 20% of approved amount | None | Rarely |
| Original plus Medigap Plan G | $283 | Plan G pays Part B coinsurance | Generally $283 for covered Part B costs, plus premiums | Rarely |
| Medicare Advantage | Set by plan | Set by plan | Up to $9,250 in-network | Usually required |
Plan G covers his Part B coinsurance once the deductible is satisfied. In practice, the injections, scans and covered visits would usually bring no additional coinsurance, though monthly premiums still apply. Medicare Advantage plans do put a ceiling on in-network costs, and that cap can be as high as $9,850 for 2027. But an Advantage plan may require approval before the first dose, restrict him to a network, and leave out Part D drugs and out-of-network care.
The bigger problem may be what happens before treatment even starts. At 70, his one-time Medigap open enrollment window closed years ago. In most states, insurers can now look at his medical history, and a cancer diagnosis could lead to a denial or a higher premium. Switching from Advantage to Original Medicare plus Plan G in the middle of treatment may not be possible. Connecticut, New York, Massachusetts and Maine offer broader access, so state rules matter. Coinsurance on a drug like Qlex is only one of the Medicare surprises retirees can face.
What the Shorter Injection Really Changes
The older IV version of Keytruda takes about 30 minutes. Qlex takes around 1 minute every three weeks or about 2 minutes every six weeks. That can save chair time, parking costs and long stays in an infusion center. Whether it saves money too depends on how Medicare prices both the drug and the administration service, which has its own billing code. A shorter appointment does not automatically mean a smaller bill.
Three Steps Before the First Dose
- Ask for a written estimate. Request that the oncology billing office price Qlex using Medicare's approved amount, show the drug and administration fee separately, and confirm whether billing will come from an office or a hospital outpatient department.
- Check Medigap eligibility before assuming it is out of reach. If he has only Original Medicare, he should review his state's Medigap rules and see whether he can still qualify for Plan G. Without supplemental coverage, he faces 20% coinsurance on every injection.
- Get Advantage rules in writing. If he is enrolled in Medicare Advantage, he should confirm that his oncologist is in-network and that prior authorization covers Qlex by name. He should also compare each plan's 2027 out-of-pocket limit before open enrollment ends on December 7.
More from Digilifetrends
Take a Fresh Look at Your Medicare Coverage: Open Enrollment Runs Through Dec. 7
3 min read · Published 2026-11-09Original Medicare Leaves You Exposed to Unlimited Costs — Consider Adding Coverage First
3 min read · Published 2026-11-09Enroll in Medigap During Your Six-Month Enrollment Window, Not Medicare’s Fall Period
Sign up for a Medicare Supplement, or Medigap, plan during the six-month window that begins when you are 65 or older and enrolled in Part B. During that one-time period, insurers…
2 min read · Published 2026-11-09