The stock went up 3.69 per cent to Rs 1,448.80 on BSE.
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On NSE, it surged 3.81 per cent to Rs 1,450.
The approval by the US Food and Drug Administration (USFDA) is for multiple strengths of 6.25mg and 12.5mg of the generic version of Janssen Pharmaceuticals' Axert tablets, Ajanta Pharma said in a BSE filing on Monday.
Ajanta Pharma USA Inc, a wholly-owned subsidiary of the company, is scheduled to launch the almotriptan malate tablets in the US shortly, it said.
Almotriptan tablets is a part of an "ever growing portfolio" that the company has developed for the US market, the company added.