Studies conclude impurity in Roche's Viracept did not increase patients' risk of cancer

Basel, 24 July 2008. The European Committee for Human Medicinal Products (CHMP) has confirmed that the presence of an impurity called ethyl methanesulfonate (EMS) in Roche's Viracept (nelfinavir mesylate) did not increase patients' risk of developing cancer.

The discovery of the EMS impurity in some batches of nelfinavir led to a global recall of this HIV medication in June 2007. Since then, the product has been made available again in the EU.

The conclusions announced today were based on tests with EMS, which have been validated by independent experts including toxicologists and HIV-treating clinicians. The results were also reviewed by patient advocates and non-governmental organisations.

"Roche has acted promptly and responsibly in generating this new research on EMS" said Dr Anton Pozniak, Consultant Physician in HIV, Chelsea and Westminster Hospital, London, UK. "The results of the studies – validated by a panel of independent toxicologists and clinicians – as well as the conclusions of the CHMP should provide reassurance to patients who were exposed to elevated levels of EMS, and to their healthcare providers."

In collaboration with the CHMP, Roche designed and commissioned in-depth animal studies to better define the potential impact of EMS. These studies demonstrated that patients who were accidentally exposed to the highest levels of EMS in nelfinavir received doses of the impurity significantly below the threshold at which DNA damage – and therefore cancer or birth defects – can occur.

"Our primary focus throughout this process has been on protecting the safety of patients" said William M. Burns, CEO, Roche Pharmaceuticals Division. "Roche undertook this important research because so little was known about EMS at the time the recall was initiated. We welcome the CHMP's conclusions and expect that the rapid generation and dissemination of the data will make an important contribution to the industry as a whole."

The full data will be shared with the broader HIV and research communities via scientific conferences and peer-reviewed journals in the coming months. An initial presentation has been accepted as late-breaker poster at the XVII International AIDS Conference, 3-8 August, 2008.

Additionally, Roche had initiated the first steps to establish patient registries as part of its efforts to monitor and track patients who may have been exposed to contaminated batches of nelfinavir. However, in light of the new research, the CHMP has concluded that there is no need to follow these patients in registries.

Following the discovery of elevated levels of EMS in some batches of nelfinavir, Roche in June 2007 undertook a total global recall in areas of the world where it supplies the drug. This was followed by the suspension of nelfinavir's licence in August 2007. In agreement with the CHMP, Roche undertook a comprehensive review and correction of its manufacturing procedures, which led to nelfinavir's licence being reinstated in October 2007.

Source: Ketchum