MANILA - The Philippines will take legal action against French drug maker Sanofi if it refuses to fully refund the P3.5 billion spent on its controversial anti-dengue vaccine by next month, the country's health secretary said Tuesday.

Sanofi has paid an initial P1.16 billion refund for unused Dengvaxia doses earlier this month.

• Sanofi refunds P1.16-B worth of unused Dengvaxia

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Health Secretary Francisco Duque III told radio DZMM that he wrote Sanofi on Friday, demanding a refund for used Dengvaxia doses as well because "the purported protection that they claim did not necessarily happen."

He said he gave Sanofi 15 days, or until February 10, to discuss this with their head office.

The Philippines will "be forced to take a legal action to protect the government and taxpayers' money" if Sanofi rejects the demand, said Duque.

The French pharmaceutical firm last year said the vaccine Dengvaxia could lead to more severe symptoms if given to those who have not had the mosquito-borne disease before. This prompted the government to scrap its immunization program for school children using the drug.

• Philippines suspends dengue vaccine program after Sanofi warns of risks
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Duque earlier said he will also ask Sanofi to allocate funds for the families of children who allegedly died after receiving Dengvaxia.

Some 830,000 public school students were inoculated with Dengvaxia under the campaign launched by the previous administration.

At least 5 vaccine recipients died less than 6 months after receiving the drug, the Public Attorney's Office had claimed.

• PAO probes death of 5th child who received dengue vaccine

The Senate is set to resume its investigation into the issue on the first week of February.