In a warning letter, USFDA said inspectors in March had found significant deviations from standard manufacturing practices at Cadila Pharmaceuticals' Ankleshwar plant, which manufactures active pharmaceutical ingredients.
The significant violations included the failure of the company to adequately probe or take corrective action after customer complaints between 2011 and 2012 about unpleasant odours from, and impurities in, certain drug batches sold in the US, the USFDA said.
The company did not have proper controls in place to prevent the unauthorised manipulation of its electronic raw data, it added.
In addition, the company's failure to correct these violations may result in FDA refusing admission of articles manufactured at Cadila Pharmaceuticals' Ankleshwar plant into the US, it added.
The FDA issued the letter on October 15, and has given the company 15 days to respond.
The company could not be reached for comments over the FDA letter.