10 key facts about Dengvaxia, world’s first dengue vaccine

- Sneha Bhattacharjee

With the world’s first dengue vaccine, Dengvaxia, being given the approval by Mexico’s regulatory authority under the Ministry of Health COFEPRIS; the international health body, World Health Organisation (WHO) has said that it will help in achieving the WHO goal of reducing dengue morbidity by at least 25% and mortality by at least 50% by 2020.

From the background of the trials, to their result and its implication on India, here are the ten key facts about Dengvaxia that you should know:

1) The manufacturer: The vaccine has been manufactured by a French company Sanofi Pasteur and has successfully cleared the phase three trials in two continents where the dengue virus is widespread - Asia and Latin America.

2) For whom is the vaccination meant: The vaccination has been approved for people belonging to the age group 9-45 years only. It has also been approved for people living in countries where the virus is known to be in circulation. However, it does not apply to the tourists.

3) The vaccine’ effectiveness: The vaccine is tetravalent, thus provides protection against all four virus serotypes. Though the dengue virus circulates in only these four serotypes (Types 1-4), each type varies from outbreak to outbreak.

4) Results of the trial phase: The recent study conducted on the efficiency of the vaccine shows that it reduces the risk of hospitalisation in patients aged 9 and above. Further, the trials exhibited that the vaccine had greater efficiency in patients who have been diagnosed with dengue earlier and not much on the population that’s yet to experience it.

5) India as a participant: There were initial trials on Indian adults in the age group 18-45 years, performed in the cities of Delhi, Bengaluru, Pune, Ludhiana and Kolkata. The trials found the vaccine to be safe and immunogenic.

6) Licence clearance: Based on the database and the trial results in India, Sanofi is slated to apply for licence in India. The vaccine will be rolled out only after the approval of Drug Controller General of India (DCGI).

7) Cost of the vaccine: The manufacturer and COFEPRIS are yet to mention the price of the vaccine but has said that the vaccine will be first made available in the countries where dengue is widespread, whereas it will hit the Mexican market only next year. From the Indian perspective, the cost of vaccine plays a key role if it has to be a part of mass immunisation program in the country.

8) The need for the vaccine: Since there are no other means to control the spread of dengue, and it is only based on the symptoms that one faces, a vaccination becomes important to ensure the spread/control.

9) Does India have its own vaccine?: The trials for the dengue vaccine that has been under research since 2007 have shown positive results on mice and are slated to be tried on primates in the next phase however, it will take at least five more years for the trials to happen on humans.

10) Repercussions of the vaccine: While the WHO in a report has questioned the requirement of three doses of the vaccine, experts opine that the vaccine’ use of live forms of all four serotypes might result in the formation of antibodies against all four strains in the body instead of one or two that might be prevalent in the body. This unnecessary creation of antibodies might have its own repercussions in the long run on the body.