Double vaccine victory over rotavirus
Two of the largest ever clinical trials have shown that two separate vaccines can prevent nearly all severe cases of a disease that kills about one child every minute in the developing world.
Pharmaceutical companies Merck and GlaxoSmithKline are launching the vaccines, called Rotateq and Rotarix, respectively. They have been found to be safe and effective at fighting the diarrhoea and vomiting caused by the rotavirus, which kills half a million infants in the developing world each year.
Rotateq, given in three doses, prevented 98 per cent of severe infections, whilst Rotarix, given in two doses, protected at least 85 per cent of children.
The results are published this week in two papers in the New England Journal of Medicine.
In an accompanying editorial, Roger Glass and Umesh Parashar, of the US Centers for Disease Control and Prevention, put the slight differences in trial results down to differences in the populations studied and how the severity of disease was classified.
GlaxoSmithKline conducted its trials mostly among infants in Latin America while the Merck vaccine was tested in Finland and the United States.
International health charity PATH, said in a statement today (5 January), however, that "an unanswered question is whether rotavirus vaccines will work as well in poor populations of Asia and Africa — where the burden of rotavirus is greatest — as it has in the mostly middle-income populations of Latin America".
PATH is working with international partners, including Merck and GlaxoSmithKline, to conduct vaccine trials in Africa and Asia.
Previous efforts to tackle rotavirus with a vaccine were thwarted in 1999, when Rotashield, made by Wyeth Laboratories, was withdrawn because it caused a rare bowel disease in one in every 10,000 patients. Due to the rarity of that disease, the recent trials each involved more than 60,000 children.
Merck is seeking permission to sell Rotateq in 50 countries and will evaluate its use in the developing world.
GlaxoSmithKline's vaccine was launched in Mexico in 2005, and has since been granted licences in 24 more countries, including the Philippines, Singapore and 12 Latin American nations.Rotarix is expected to be approved for sale in Europe next month (February 2006). Rotateq is currently being approved by the US Food and Drug Administration.
Link to abstract of Rotateq article in New England Journal of Medicine
Reference: New England Journal of Medicine 354, 23 (2006)
Link to abstract of Rotarix article in New England Journal of Medicine
Reference: New England Journal of Medicine 354, 11 (2006)
Link to summary of editorial in New England Journal of Medicine
Reference: New England Journal of Medicine 354, 75 (2006)