By Stewart Bishop

Law360, New York (October 07, 2011, 7:38 PM ET) -- Massachusetts drugmaker Momenta Pharmaceuticals Inc. said Friday that it had obtained a temporary restraining order against Amphastar Pharmaceuticals Inc., Watson Pharmaceuticals Inc. and International Medical Systems Ltd. barring the rivals from selling a competing generic version of the blood-thinning drug Lovenox.

Momenta said the TRO prohibits Watson, Amphastar and its unit IMS from selling generic enoxaparin sodium pending an Oct. 20 hearing in Massachusetts federal court on its motion for a preliminary injunction, according to a statement from Momenta.

Amphastar and the others immediately fired back,...