In a major setback for pharmaceutical giant, Wockhardt, the United States Food and Drug Administration has issued an import alert for the drugs produced at the company's Aurangabad unit.

The company operated three plants in Aurangabad. The US authorities release an import alert when it believes that the drugs may harm the residents. The import alert will allow FDA to begin queries related to Wockhardt's injectable block. Extimates shows that the import alert couldcause a loss of $100 million in sales if the alert is expected to the company's entire Export Oriented Units (EoU).

The company's leading drug, Toprol XL, which has sales of more than $120 million is not manufactured in Aurangabad. The company's Flonase or any high value products are also not produced at the plant targeted in the alert. The alert may also block the FDA approvals for the company.

The shares of the company fell as much as 20 per cent on Thursday after the US FDA issued the import alert against the company's drugs from a particular plant. The shares were trading about 20 per cent down at Rs. 1,315.25 on the Bombay Stock Exchange (BSE).