When someone first dredged up the rights for this drug, it sold 667,000$ worth of pills every year for 1$ each. GlaxoSmithKline produced it and it just wasn't

When someone first dredged up the rights for this drug, it sold 667,000$ worth of pills every year for 1$ each. GlaxoSmithKline produced it and it just wasn't worth the trouble to discontinue or to muck about with. No one would make a generic because it would be more expensive to enter the market than profits could be realized. So the monopoly is natural because no one with any good sense would consider competing. That GSK sold the rights to this drug (and quite possibly other similar drugs) to some other company in a rational bid to monetize inefficient assets and increase shareholder value has upset that monopoly but Turing just needs to exploit the market until the generics show up. That and the price they paid explain Turing's strategy.