The US government has filed a suit against Ranbaxy Laboratories [Get Quote], India's largest pharmaceutical company, and its US-based consultant Parexel Consulting for concealing and forging crucial data to get a favourable judgement on an ongoing investigation into the sale of sub-standard drugs in that country.

The suit, filed with the District Court of Maryland, has sought a direction to Ranbaxy and Parexel to submit all relevant documents for verification.

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If proved, the allegations could have a serious impact on Ranbaxy's US operations that contributed 23 per cent to the company's total turnover of over Rs 6,000 crore (Rs 60 billion).

When contacted, a Ranbaxy spokesperson said "a motion has been filed (not granted) seeking certain documents and no legal proceedings in the sense of a prosecution have been started. Ranbaxy strongly denies the allegations contained in the motion. Meanwhile, we continue to co-operate with the inquiry."

He said the allegations of "systematic fraudulent conduct' about drugs manufactured in the company's plant in India" are baseless as the US FDA has verified over 200 random samples of various products marketed by the company in the US  and all were found to be complying with all the specifications as per the filing.

Ranbaxy said it would file its response to the court on July 14.

According to the US court document, the investigation involves allegations of conspiracy, false statements and fraud relating to the health care benefit programme of the US Government and failure to maintain quality control systems and records at Ranbaxy's manufacturing facilities in India.

The US Department of Justice is also investigating whether Ranbaxy committed "contract fraud and submitted false claims to Federal health benefit programmes, fabricated bio-equivalence and stability data (necessary to prove efficacy of a drug) to support marketing applications filed with the US drug regulator for selling generic drugs in the US and for supply of generic HIV/AIDS drugs under the US President's Emergency Plan for AIDS Relief".

The investigation stems from an FDA inspection of Ranbaxy's facilities at Panota Sahib in June 2006, where it found discrepancies in manufacturing processes and maintanence of data. In this connection, the federal agents had raided Ranbaxy's US office last year.

Ranbaxy and Parexel Consulting, which was appointed by Ranbaxy to rectify the defects, have been charged with withholding and forging crucial information from the regulator to get clearance for further manufacturing of drugs at its Panota Sahib facility.

The outstanding documents demanded by the agency include two specific draft standard operating procedures, details on the Toansa plant and the API facilities of Panota sahib, validation protocals and reports for two products, and certain quality control procedures, detailed by the consultant.