GlaxoSmithKline is hoping that Rotarix, its rotavirus vaccine, will get the go-ahead from US health regulators this Wednesday after Food and Drug Administration staff posted a fairly positive review on the jab on the agency’s website.

The review said that Rotarix appeared to be effective at protecting against rotavirus, the primary cause of severe acute gastroenteritis in young children. However the staffers also expressed concern about data suggesting that the vaccine is associated with an increased risk of pneumonia-related deaths and other adverse events.

In its analysis, the agency staff examined 11 studies and said the data do not suggest that Rotarix increases the risk of intussusception. However, the staff also found that in one trial there was a statistically significant increase in the number of pneumonia-related deaths in those administered Rotarix compared with those who received placebo. Results from the study, which involved about 63,000 children, also demonstrated increased convulsions in those who received Rotarix, the staff noted.

GSK, in documents provided ahead of the FDA advisory committee on Wednesday, noted that respiratory infections like pneumonia account for "dramatically greater numbers and proportions of infant deaths in Latin America, compared to the USA”.

Rotarix is already available in Europe but needs to make up ground in the USA on Merck & Co’s Rotateq. GSK’s two-dose regime, compared with Rotateq’s three-dose course, could give the UK-based drugmaker an advantage but that will not be the case if the FDA wants more safety data.