A US judge said Tuesday that he would take "under advisement" a request by sanofi-aventis to block the sale of a generic version of its Lovenox from Novartis' Sandoz unit and Momenta.

US Judge Emmet Sullivan said he would "issue an appropriate decision as soon as I can," but gave no specific timetable for doing so.

Sanofi-aventis attorney, Emily Johnson Henn, noted that the company has "a strong likelihood of success on the merits" of the case.

However the defence counters that sanofi-aventis will suffer no irreparable harm if it has to wait for a trial on the merits.

Novartis last month won FDA approval to market a generic version of the drug, using Momenta's technology.