The company's product is being sold in the United States by its marketing partner Caraco Pharmaceutical Laboratories, it added.
This generic amifostine injection is therapeutically equivalent to Medimmune's Ethyol amifostine injection of 500 mg strength, the company said.
Amifostine is used as an adjuvant in cancer treatment. Sun Pharma's amifostine injection would be used for reduction of kidney damage in patients who have advanced ovarian cancer.
On March 17, Sun Pharma had received US Food and Drug Administration's approval for marketing the generic Ethyol. The firm was the first-to-file an Abbreviated New Drug Application for generic Ethyol and had an 180-day marketing exclusivity, the company said.
Ethyol is covered under three patents and this ANDA was filed against all the patents. Meanwhile, Medimmune has filed a suit in the District Court of Maryland and the case is under litigation, Sun Pharmaceutical said.
Shares of the firm were trading at Rs 1,240 in morning, down 0.89 per cent on the BSE.