A Canadian subsidiary of pharmaceutical company GlaxoSmithKline (GSK) has been accused by the US Food and Drug Administration (FDA) of deviating from good manufacturing practice (GMP) regulations while manufacturing the flu vaccine FluLaval.

The allegations, contained in a Warning Letter released by FDA on 24 June 2014, stem from a 31 March-9 April 2014 inspection of ID Biomedical Corporation's—a GSK subsidiary since 2005—Quebec facility.

The bulk of the allegations contained within FDA's Warning Letter focus on a general failure to maintain microbiological controls at or above federal standards.

For example, FDA claimed that the purified water used in the manufacture of FluLaval was "inadequate to prevent bioburden and endotoxin excursions," or in plain terms, that the water wasn't free of microorganisms. FDA said records examined by its inspectors indicated several instances over the last two years when ID Biomedical employees had discovered bacteria and other organisms in the water, and commented that the company lacked a "set schedule" for disinfecting the water system at regular intervals.

FDA inspectors also expressed concern about the company's manufacturing controls, which it claimed had been insufficient to control contamination and/or endotoxins. Those problems had existed for years despite attempts to correct them, FDA observed.

In another case, FDA said it had observed documents indicating that the company had been unable to determine if lots of its vaccine— an inactivated virus incapable of causing the flu—had in fact been inactivated, potentially leaving patients at risk.

FDA said the totality of the deficiencies noted in the Warning Letter—a type of letter threatening future enforcement action unless actions are taken to address the agency's concerns—were "an indication of your quality control unit not fulfilling its responsibility to assure the identity, strength, quality, and purity of your licensed biological drug product and intermediates."

"FDA expects ID Biomedical and GSK to undertake a comprehensive and global assessment of all of its manufacturing operations to ensure that all products conform to FDA requirements," FDA wrote. "Given the potential contributions of Flulaval to the public health, we encourage frequent interaction between your management and technical staff with FDA to help ID Biomedical and GSK move forward with corrective actions as rapidly as possible."

FDA said GSK had already been in contact with the agency three times, and that regulators had requested a meeting with the company's senior management to "discuss the issues cited in this letter"—a highly unusual measure rarely mentioned in FDA Warning Letters.