Contaminated rotavirus vaccine: avoid ROTARIX until further notice? The oral vaccine ROTARIX contains an attenuated human rotavirus strain and is authorised for the prevention of rotavirus-induced gastroenteritis in babies from six weeks of age (a-t 2008; 39: 111-4). To date, the vaccination has not been included in general vaccination recommendations. Using a new polymerase chain reaction (PCR) method, independent US researchers have now identified DNA from porcine (pig-derived) circovirus 1 (PCV-1) in ROTARIX and in the viral seed stock. The contamination must therefore have been present from the onset in ROTARIX, which is produced on Vero cells (kidney cells from Green Monkeys) in a Belgian subsidiary of GlaxoSmithKline. GSK and the licensing authorities stress that, although PCV-1 is widespread in pigs, there is no evidence of infection or spread in humans (1-3). Preliminary test results, including the new PCR method, have found no traces of PCV-1 in the competitor product ROTATEQ, which is also propagated in Vero cells (4).
The national differences in the strategies of the licensing authorities are noteworthy. In Europe, while the EMA notes that the extraneous virus constituents should not be present in the vaccine, it - like the German Paul Ehrlich Institute (PEI) - does not regard the contamination as a risk or a reason to restrict the use of ROTARIX (1,5). The EMA appears to be less stringent in this decision than it is in relation to the clopidogrel generics, whose Indian raw-material producer drew attention to itself by formal deficiencies in the organisation of production (see a-t 2010; 41: 41). The PEI intends to conduct its own tests to determine whether "intact virus particles and viruses that can multiply in tissue cultures can also be identified" (6). Conversely, America's FDA is advising doctors to suspend use of the vaccine temporarily until the authorities have further data - "as agency learns more" (2). The Swiss Agency for Therapeutic Products, Swissmedic, and the Hong Kong authorities came to similar decisions (3,6). These recommendations follow the principle of preventive consumer protection. The strategy of the EMA and PEI - to give the all-clear and then check - leaves the risk of the contamination, which in this case is probably low, with the vaccinated baby and not the manufacturer.
In 2009, GSK's worldwide sales of ROTARIX amounted to 320 million Euros (4). If vaccination is considered at all, ROTATEQ should be used - as the FDA has recommended. It is probably no coincidence that GSK has just lowered the price of ROTARIX in Germany by 25% (7) - Red.