The World Health Organization will review the safety data on French pharmaceutical company Sanofi Pasteur’s dengue vaccine this month, after the company last week said that the Dengvaxia vaccine could make the disease worse in some cases, Reuters reported.
“The analysis confirmed that Dengvaxia provides persistent protective benefit against dengue fever in those who had prior infection,” Sanofi said in a statement on November 29. “For those not previously infected by the dengue virus, however, the analysis found that in the longer term, more cases of severe disease could occur following vaccination upon a subsequent dengue infection.”
Dengue is a mosquito-borne disease that kills about 20,000 people annually.
The Philippines has ordered an investigation into the immunisation of more than 7.3 lakh children, Reuters reported. The government had stopped the use of the drug – the first approved vaccine for dengue – last week. Brazil, where dengue is a major healthcare issue, has already recommended restricted use of Sanofi’s vaccine.
In Manila on Monday, Sanofi Pasteur’s Global Medical Head Ng Su Peing insisted that the vaccine is beneficial, The Philippine Star reported. However, she did not say why the company did not act after the WHO identified the risk in 2016.
The drug still provides up to six years of protection against the disease to those with a history of dengue infection and reduces the severity of the disease by 80%, Peing said. She added that three out of four dengue cases do not usually show symptoms of the disease after being treated with Dengvaxia, but admitted that Sanofi did not recommend using it to treat individuals with no previous record of dengue infection.