Enoxaparin: US court affirms inequitable coduct against Sanofi

A U.S. federal court affirmed a ruling that Sanofi-Aventis intended to deceive the patent office in its dispute over generic versions of its blockbuster drug Lovenox.
Sanofi, the world's third-biggest drugmaker, has sued Teva Pharmaand Amphastar Pharma over their bid to sell a generic version of Sanofi's Lovenox, a blood-thinning drug that had sales of about $1.1 billion in the first quarter of 2008.
Enoxaparin (6-[5-acetylamino-4,6-dihydroxy-2- (sulfooxymethyl)tetrahydropyran-3-yl] oxy-3- [5-(6-carboxy-4,5-dihydroxy-3- sulfooxy-tetrahydropyran-2-yl)oxy-6-(hydroxymethyl)- 3-sulfoamino-4-sulfooxy-tetrahydropyran-2-yl] oxy-4-hydroxy-5-sulfooxy-tetrahydropyran-2- carboxylicacid ) is a low molecular weight heparin manufactured by Sanofi-Aventis. It is marketed as Lovenox or Clexane. Enoxaparin injections are derived from the intestinal mucosa of pigs. Enoxaparin is used to prevent and treat deep vein thrombosis or pulmonary embolism, and is given as a subcutaneous injection (by a health care provider or the patient). Its use is evolving in acute coronary syndromes (ACS).
Following patents are listed in Orange book for this product
US5389618 (Expiry: Feb 14, 2012)
USRE38743 (Expiry: Feb 14, 2012)
Earlier Amphastar and Teva ‘s Motion for Summary Judgment was granted on June 15, 2005, which held '618 patent invalid due to inequitable conduct. The USPTO reissued the disputed patent in June 2005 as USRE38743. Subsequently Aventis filed a Motion to substitute '618 for '743. On July 2005, the district Court granted the substitution of the patents and also entered final judgment on inequitable conduct grounds.
The U.S. Court of Appeals for the Federal Circuit ruled that pharma giant Sanofi-Aventis had committed "inequitable conduct" for failing to inform the U.S. patent office of information relevant to patentability.
The inequitable conduct was alleged w.r.t EP40144, which was granted in Europe as patent in 1980 (Which got revoked in 1990). The said patent covers the same invention as disclosed in ‘723. Aventis got ‘618 patent after overcoming 3 rejections by USPTO. Finally, Aventis demonstrated that pharmacokinetic profile with respect to t1/2 is better in ‘618 patent in comparison to ‘144 patent.
The federal court affirmed the ruling by a district court in California that there was an intent to deceive by Sanofi-Aventis in its failing to disclose dosages of the drug in pharmacokinetic studies.
The judge Radar dissented the ruling, arguing that inequitable conduct should be reserved for only the most extreme cases of fraud and deception, which he said did not apply in this case. In his dissenting note judge said that Aventis may have been careless, but hardly culpable
The USFDA has not cleared any generic form of Lovenox. (opinion of Court)