Staff Writer

The FDA denied Teva Pharmaceuticals Inc.'s latest attempt to block generic competition to Copaxone (glatiramer acetate) - but hurdles remain for generic Copaxone maker Momenta Pharmaceuticals Inc.

It's been almost two years since Momenta and partner Sandoz, the generic unit of Novartis AG, filed an abbreviated new drug application seeking approval of M356, their generic version of Teva's multiple sclerosis drug Copaxone. Although the FDA regulates Copaxone as a drug rather than a biologic, its variability of composition and complexity of manufacturing outstrip other peptide-based drugs approved through the ANDA process. (See BioWorld Today, July 14, 2008.)

Teva filed a citizen petition with the FDA arguing that Copaxone contains trillions of polypeptide sequences that have not been fully characterized, making it impossible for a generic version to establish that it has the same active ingredients.

The FDA disagreed. In a ruling sent to Teva this week, the agency said it has "broad discretion" in determining what information is required to establish sameness. The FDA further noted that its "flexible, science-based approach to determining active ingredient sameness has been sustained by the courts."

So while the FDA acknowledged that it will consider Teva's claims regarding Copaxone's complexity when making its final decision, it won't dismiss the M356 ANDA out of hand.

That's good news for Momenta, but it's just one step down a very long and bumpy road.

First off, there's the issue of patents. Teva holds seven patents on Copaxone that do not expire until 2014. Momenta and Sandoz have sought to invalidate those patents with a paragraph IV filing, but that will take some time to play out. Leerink Swann analyst Joseph Schwartz wrote in a research note that he expects the lawsuit to go to trial in the second half of this year, although there is a "small possibility" that a judge could issue a summary ruling sooner.

But even if Momenta and Sandoz did beat Teva's patents, they still have to get their M356 ANDA approved. Wedbush Pacgrow Lifesciences analyst Duane Nash noted that while novel drugs go through clinical trials and produce data that can be analyzed by investors to handicap an FDA decision, generic drug data are confidential. No one except Momenta and the FDA knows just how similar M356 and Copaxone really are.

Additionally, generic drugs don't get a prescription drug user fee date, so there's no telling when the FDA will make its decision regarding M356's approvability.

No one knows that better than Momenta and Sandoz. The companies have been trying for years to get FDA approval of their ANDA for a generic version of Lovenox (enoxaparin, Sanofi-Aventis Group). Like Copaxone, Lovenox is a complex molecule with biologic-like properties. The FDA rejected their ANDA in 2007, citing a failure to adequately address the drug's potential for immunogenicity, but the companies resubmitted.

Nash said "conventional wisdom" indicated that a long-awaited generic Lovenox approval might have been coming last year, but the tainted heparin crisis distracted the FDA and increased the scrutiny on heparin products. Nash said Sanofi and the various players pursuing generic Lovenox recently have been "sending smoke signals saying approval of a generic is imminent," but no one knows for sure if or when it will happen.

Spokespersons from Momenta declined to comment, given that both its generic Lovenox and generic Copaxone products are under active review.

Nash noted that while Lovenox and Copaxone seem to be biologics, the FDA regulates them as drugs, so the follow-on-biologics legislation passed in the recent healthcare reform legislation shouldn't have an impact. The new law specified that biotech drug innovators will get 12 years of data exclusivity protection before follow-on biologics can hit the market, but Congress left the remaining details of creating an approval pathway up to the FDA. (See BioWorld Today, March 23, 2010.)

Oppenheimer & Co. analyst Bret Holley wrote in a research note that the FDA's rejection of Teva's petition indicated the agency has adopted a "somewhat loose definition" of sameness for complex mixture drugs. He added that the rejection showed the agency is asserting its authority to review ANDAs for generic biologics on a case-by-case basis.

Yet Nash was wary of reading too much into the FDA's ruling against Teva. "I don't think we have tremendous insight into what the FDA is planning to do" about follow-on-biologics, he said.

Shares of Cambridge, Mass.-based Momenta (NASDAQ:MNTA) dipped 6 cents to close at $13.76 on Thursday, while shares of Jerusalem-based Teva (NASDAQ:TEVA) slid 85 cents to close at $57.82.