In the US, the question of whether or not pharmaceutical companies should be able to pay off competitors challenging their patent exclusivity may now be left to Congress.

“The effort has been fought to a stalemate in the courts,” says Lauren Fuller, director of legislative affairs for the Academy of Managed Care Pharmacy, a managed-care advocacy group that supports outlawing such 'pay-for-delay' deals. “We need to take care of this legislatively.”

Under the 1984 Hatch-Waxman Act, makers of generic drugs can begin producing generics before the original drug patent expires by challenging the validity of that drug's patent. Instead of fighting the battle in court, the patent holders often simply pay the generic makers to drop their efforts.

Such was the case when Barr Pharmaceuticals struck a deal to drop its challenge to Bayer's Cipro patent in 1997. With the support of the Federal Trade Commission, a cadre of organizations, including CVS Pharmacy and Rite Aid took the agreement to court, accusing such pay-for-delay deals of violating antitrust laws and unlawfully delaying the distribution of more affordable generics.

On 7 September, a US appeals court in New York may have effectively ended that fight by refusing to reconsider an earlier decision that such deals cannot be denied—in large part because to do so would effectively force companies to pursue litigation. The rational is typically dubbed the “Tamoxifen doctrine,” named after a similar 2006 case involving the cancer drug.

The last chance to resolve the issue in the court system would be if the Supreme Court decides to hear the case, but many proponents of outlawing pay-for-delay deals, such as Rutgers Law School antitrust expert Michael Carrier, are skeptical this will happen, largely because the court has refused to hear similar cases in the past, including the Tamoxifen case.

The “Preserve Access to Affordable Generics Act,” which would effectively nix pay-for-delay deals, is currently included as part of the Senate's 2011 financial services appropriations bill. Prior to the congressional summer recess, the act narrowly escaped exclusion from the bill by a group of senators who claim that the act would actually inhibit generic drugs by drawing companies into long and legal disputes.

The timeline for the bill's approval is not certain. The act could still be removed before the Senate's vote, which may be delayed until after the midterm elections in November.