UPDATE 2-Momenta sues Teva over generic Lovenox

* Momenta accuses Teva of patent infringement

* Teva says generic Lovenox lawsuit without merit

* Momenta shares up 1.5 pct, Teva shares down 0.4 pct (Adds Teva comment, closing share prices)

NEW YORK, Dec 2 (Reuters) - Momenta Pharmaceuticals Inc MNTA.O said it sued Teva Pharmaceutical Industries Ltd TEVA.TATEVA.O, accusing the Israel-based company of infringing its patents by producing and processing its own generic version of the blood thinner enoxaparin.

Momenta in July won U.S. approval to sell the first generic formulation of the injectable drug, which has been sold under the brand name Lovenox by French drugmaker Sanofi-Aventis SA SASY.PA and has long been used in hospitals to treat and prevent blood clots.

Momenta, which filed the suit in U.S. District Court for Massachusetts, sells its generic in partnership with Sandoz, the generic division of Swiss drugmaker Novartis AG NOVN.VX.

Teva, the world’s largest generic drugmaker, is awaiting an approval decision from the U.S. Food and Drug Administration for its version of enoxaparin. Momenta contends in its lawsuit that such an approval would constitute infringement of its patents.

Teva on Thursday said it believes the lawsuit to be without merit and that it intends to seek reimbursement “for all legal fees in fighting these baseless allegations.”

On Nasdaq, Momenta closed up 1.5 percent at $15.65, while Teva ended down 0.4 percent at $49.77. (Reporting by Ransdell Pierson and Bill Berkrot; Editing by John Wallace and Richard Chang)