Sanofi-Aventis’ sales of Lovenox in the USA are about to be hurt now that the first generic version of the blockbuster anti-clotting drug made by Novartis’ Sandoz unit and Momenta Pharmaceuticals has been given the green light.

The US Food and Drug Administration today approved the first generic version of Lovenox (enoxaparin), which is used for multiple indications including prevention of deep vein thrombosis. The agency noted that the process for approving a natural product such as Lovexox can be more complex and Keith Webber, deputy director of the FDA’s Office of Pharmaceutical Science, said the review involved “a series of sophisticated analytical tests and a study in healthy volunteers to assure that the drug would be as safe and effective as the brand name product".

The FDA had received a citizen petition from Sanofi questioning the criteria for assessing generic enoxaparin but the agency has decided that “current scientific evidence, precedent, and FDA's legal authority establish a sound basis for the approval”.

Momenta is delighted that its drug, called M-Enoxaparin, has been designated therapeutically equivalent to Lovenox. Chief executive Craig Wheeler noted that “this is the first product based on Momenta's technology platform to be approved, and demonstrates our ability to characterise and develop a complex mixture drug".

Sandoz is pretty pleased as well, and noted that “product shipment began immediately” after the approval for its version of “the 'gold standard' for anti-thrombotic treatments”. Global head Jeff George said “we are now looking forward to significantly increasing patient and payor access to this vital medicine, by providing a high-quality, more affordable version”.

Lovenox is a big earner and recorded US sales of $2.7 billion in 2009. It has been used to treat 200 million patients worldwide and is the best-selling hospital-based medicine in the USA.

Sanofi doubts quality of M-Enoxaparin
Sanofi is not impressed and says that the Momenta/Sandoz version "has not been assessed on the basis of an extensive clinical programme showing proven and comparable clinical efficacy and safety to Lovenox". The French drugmaker adds that it will avail itself of "appropriate analytical and clinical avenues to assess the quality, efficacy and safety of the product and is considering all appropriate legal options".

Other companies looking to get the go-ahead for their versions of Lovenox are encouraged by the FDA’s decision. Teva Pharmaceutical Industies said that after reviewing the agency's response to the citizen petition, which outlines five criteria to demonstrate "sameness”, the Israeli drugmaker believes “it has demonstrated to the FDA that its version of generic Lovenox meets their criteria and that Teva's pending Abbreviated New Drug Application is approvable”.

Amphastar Pharmaceuticals had been hoping to be the first firm and has been involved in a bitter dispute with Janet Woodcock, director of the FDA’s Centre for Drug Evaluation and Research. Last year, the company filed an official ethics complaint against Ms Woodcock, who worked with Momenta scientists in 2008 following the scandal of tainted heparin on the market sourced from China.

Amphastar claimed its ANDA, filed in 2003, has been delayed while Momenta had “special access” to Ms Woodcock once its file was submitted for approval two years later. However in February this year, the FDA dismissed Amphastar’s claims as Ms Woodcock voluntarily removed herself from considering the Momenta and Amphastar filings.

The importance of the generic Lovenox approval is considerable to the industry as a whole, analysts have noted. Simos Simeonidis at Rodman & Renshaw said that the biggest impact of the FDA’s decision has more to do with “the fact that the premise behind which Momenta was founded (ie the power and promise of its technology) will have now been validated” and that the FDA “will have approved the generic of a complex molecule, making the possibility of approvals for similar products much more tangible”.