According to AHIP Solutions SmartBrief
A Government Accountability Office report found 58% or $324 billion of Medicare Parts B and D drug expenditures between 2016 and 2018 went to drugs advertised to consumers. AbbVie's Humira, Pfizer's Lyrica, Bristol-Myers Squibb's Eliquis and Merck's Keytruda, which were the drugs with the most advertising spending in 2018, were among the top 10 drugs with highest Part B or Part D spending.
If the cost of the drug is very high for you even with your Part D, you can also use a drug discount card like Good RX. These drugs can cause you to hit the "donut hole" sooner. If you have more questions, call me.