Teva like Novartis owns hundreds of generic
drug companies and breaks patents all over the place. Generic
companies do not have to advertise, they can't be sued, and they do not have to pay for R&D. Teva only make patent drugs for MS and Cancer which are expensive and less likely to be in law suits.
We in the U.S. pay more because in other countries the governments buy drugs in bulk and negotiate prices, Teva and Novartis are not U.S.