Domestic firms Aurobindo Pharma, Glenmark Pharmaceuticals and Natco Pharma have received US health regulator's approval to market their generic Rizatriptan Benzoate orally disintegrating tablets used for treating migraine in the American market.

While Aurobindo and Glenmark said they will launch the product immediately, Natco Pharma said it has already commenced shipment of the product.

The final approval from the US Food and Drug Administration (USFDA) is for Rizatriptan Benzoate orally disintegrating tablets (ODT) in strengths of 5 mg and 10 mg, the companies said in separate statements.

The products by all the three domestic firms are generic version of Merck's Maxalt MLT tablets in the same strengths and are indicated for the acute treatment of migraine in adults and in paediatric patients aged 6-17 years.

Natco said its partner Breckenridge Pharmaceuticals will market the products.

Shares of Aurobindo Pharma, Glenmark Pharmaceuticals and Natco Pharma were today trading in the afternoon at Rs 186.10, Rs 574.15 and Rs 456.45, respectively on BSE, down 0.43 per cent, up 0.98 per cent and up 1.57 per cent from their previous close.