The Medicines and Healthcare products Regulatory Agency (MHRA) has issued notice of non-compliance for GSK's Tianjin unit after a June inspection uncovered "a critical deficiency" related to stability problems with some non-sterile products made at the plant.
The GSK (Tianjin) Co Ltd facility has not been operational since the site on which it operates was rocked by a series of blasts in August, but the problems cited by the MHRA date back well before that event.
The notice reports that as far back as 2005 GSK had identified tablet discoloration in stability samples taken at the plant, and determined that the affected products did not meet shelf-life specifications.
However, "no action was taken to assess the risk of the remaining products in the markets," according to the MHRA inspectors, who note that the affected products included various tablet formulations of GSK's gastrointestinal drug Zantac (ranitidine) destined for sale in Western European markets.
Meanwhile, adverse trends in stability-indicating attributes were observed but not investigated, and GSK did not take sufficient action to make sure that the defective products were not supplied to the user.
The company has also been upbraided for failing to notify the authorities about the quality issue and for failing to have an effective corrective and preventive actions (CAPA) system in place to root out the cause of the defect.
The notice - which is posted on the EudraGMP database - notes that the facility "should not be named on any marketing authorisations whilst this statement remains in place."
GSK operates another facility in Tianjin called Sino-American Tianjin SmithKline & French Laboratories Ltd, but this is unaffected by the GMP ruling.
The problems affecting the plant are not expected to have a significant impact on GSK, as Zantac lost its patent many years ago. It is now a minor product for the company, part of the established products unit that had been earmarked for a sell-off last year until GSK had a change of heart.