Teva Pharmaceutical Industries Ltd. said Monday it received tentative approval from the US Food and Drug Administration for its abbreviated new drug application (ANDA) for Adenosine Injection, 3 mg/ml in 20 ml and 30 ml single dose vials. On final approval, the injection will be the AP-rated generic equivalent of Astellas Adenoscan Injection, a product used as an supplement to thallium-201 myocardial perfusion scintigraphy in patients unable to exercise adequately. The brand product has annual sales of approximately $163 million. Teva is currently in patent litigation over the product after a suit was brought against the company in May 2005. A trial is scheduled to begin in 2007.