In yet another strange twist involving the trajectory of the world’s biggest-selling medicine, there are reports today that Teva Pharmaceuticals will assist with an upcoming launch of a generic version of the Lipitor cholesterol pill in the US. How is this possible when Ranbaxy Laboratories was awarded the exclusive right? Supposedly, a collaboration between the two drugmakers can make it happen by month’s end, when the Lipitor patent expires stateside.

The news first surfaced today in the Israeli media after Teva held its quarterly earnings conference call. Citing the Calcalist web site, which tracks Israeli business, Yediot Aharanot reported that the Israeli drugmaker is busy making plans to sell generic Lipitor (see here). The speculation was also fueled by an investor note from Bernstein Research analyst Ronny Gal, who posited that Teva revised guidance due to a large launch for an undisclosed product.

The circumstances actually remain unclear and a Teva spokeswoman writes us to say the drug maker has no comment. But the episode is causing intrigue, because the implications are significant - and not only for drugmakers, but also patients and payers. A deal between Teva and Ranbaxy would allow a generic to arrive by the end of November as planned along, offering price competition to both the brand-name pill sold by Pfizer and an authorized generic to be sold by Watson Pharmaceuticals. Remember that Ranbaxy may have 180 days in which to sell a generic exclusively, depending upon an FDA ruling.

For those of you who are wondering why Ranbaxy might need help to distribute Lipitor, the Indian drugmaker has been under a cloud due to manufacturing problems. Three years ago, federal prosecutors cited Ranbaxy for allegedly falsifying records resulting in the production and sale of meds failing to meet FDA standards. The charges included fabricating bioequivalence and stability data. Later, the FDA issued warnings letters and banned more than 30 meds made at two plants (see this). The FDA has not yet issued its decision.

Meanwhile, the November 30 date for launching a generic Lipitor is drawing closer. But the reports that Teva is somehow involved in an upcoming launch is causing confusion, given that Shibani Malhotra of RBC Capital Markets wrote yesterday that “market intelligence indicates that Ranbaxy has built inventory and is planning for a near-term launch.”

Separately, Bernstein Research analyst Tim Anderson also wrote that there is “no evidence that Ranbaxy is ready to take orders from purchasers for its generic,” although he adds that the FDA “will be under intense pressure to approve Ranbaxy, otherwise it is a detriment to patients and payers,” including the US government.

“It’s very mysterious,” says Michael McCaughan, a co-founder of Prevision Policy and editor of The RPM Report. “As far as I understand it, there is no way for Ranbaxy to give its exclusivity to another manufacturer… At the time they filed (to sell generic) Lipitor and, according to court decisions, (Ranbaxy) could either have US exclusivity or waive it all together. And if you waive it all together, any generic could be launched…And if there is an agreement in place, why not announce it?” He suggests the revised guidance might have referred to a generic version of the Lovenox bloodthinner.

As an aside, Mylan Laboratories tried unsuccessfully to undermine Ranbaxy’s ability to proceed with a generic version. Earlier this year, a federal judge tossed a lawsuit in which Mylan claimed the FDA did not have the right to allow Ranbaxy to proceed with its generic launch, given the manufacturing issues. Mylan had settled separate patent litigation with Ranbaxy and was concerned that, if the FDA does not allow Ranbaxy to launch, the Lipitor market would be split between the Pfizer pill and the authorized generic from Watson (back story). We asked Mylan for a reaction to the report about Teva, but have not yet heard back.