10 most expensive drugs for Medicare Part D

Medicare Part D covers pharmacy-dispensed drugs, primarily oral drugs and some self-injectables, such as insulin. 

The 10 drugs that cost Medicare Part D the most in 2018, according to a Moody's Investors Service report: 

1. Eliquis (Bristol-Myers Squibb/Pfizer) — $4.99 billion
2. Revlimid (Bristol-Myers Squibb) — $4.06 billion 
3. Xarelto (Johnson & Johnson/ Bayer) — $3.36 billion
4. Januvia (Merck) — $3.23 billion
5. Lyrica (Pfizer) — $2.95 billion 
6. Advair Diskus (GlaxoSmithKline) — $2.39 billion 
7. Humira Pen (AbbVie) — $2.39 billion 
8. Lantus Solostar (Sanofi) — $2.37 billion
9. Imbruvica (AbbVie/Johnson & Johnson) — $1.87 billion
10. Symbicort (AstraZeneca) — $1.75 billion