US drug prices vs international generics

We track US private-pay prescription drug prices and compare them to international generic equivalents. The data shows a consistent 30 to 50 percent price gap on many off-patent molecules, with some categories priced as low as 1 to 5 percent of the US private-pay rate.

Highest mispricing this month

PMI = ((US private pay - international price) / US private pay) * 100. A PMI of 90 means the molecule trades internationally at 10 percent of the US price.

MoleculeBrandUS private payInternationalPMI
Tenofovir/EmtricitabineTruvada (PrEP)$2000.00/month$10.00/month99.5
Sildenafil 100mgViagra$35.00/tablet$0.50/tablet98.6
Tadalafil 20mgCialis$40.00/tablet$0.60/tablet98.5
Finasteride 1mgPropecia$2.50/tablet$0.10/tablet96.0
Modafinil 200mgProvigil$30.00/tablet$1.20/tablet96.0