Dengvaxia, developed by Sanofi Pasteur, became the first dengue vaccine to receive regulatory approval in 2015 and later. Subsequent investigations and studies revealed that the vaccine's effectiveness varied depending on an individual's prior dengue infection status. 

Dengvaxia is recommended by the World Health Organization for persons aged 9 to 45 with confirmed previous dengue virus infection.

According to the US Centre for Disease Control (CDC), Dengvaxia is licensed in 20 countries.

Dengvaxia Vaccine three doses administered subcutaneously and each dose given 6 months apart (at 0, 6, and 12 months) for full protection.

EFFICACY:

Overall, Dengvaxia protects children from dengue illness, hospitalizations, and severe dengue 8 out of 10 times (80%) in children who had dengue before vaccination. The vaccine protects against all four dengue virus types: dengue 1, 2, 3, and 4.

CAUTION:

It was observed that in individuals who had never been exposed to dengue before vaccination, the vaccine might increase the risk of severe dengue if they were later infected with the virus, therefore restricting the limited use of Dengvaxia only to vaccinate individuals who had cleared previous dengue infections.

Very recently, the Qdenga vaccine developed by Takeda Pharmaceuticals received regulatory approval from the European Medicines Agency, the United Kingdom, and a few other countries such as Brazil, Argentina, Indonesia, and Thailand, according to the company.

The European Commission Approved QDENGA (TAK-003) for Use in Individuals 4 Years of Age and Older.

QDENGA Becomes the Only Dengue Vaccine Approved in the EU for Use in Individuals Regardless of Previous Dengue Exposure.

EFFICACY:

After years of research, Japan's pharmaceutical giant Takeda Pharmaceutical Company has developed a dengue vaccine named "Qdenga" – offering hope for future generations. 

Indonesia has already approved the vaccine, which is expected to hit the market in early 2023.

The vaccine cut hospitalisations of recipients by 84% compared with a placebo and prevented the illness in 61%, with no significant safety risks. Although the vaccine is not equally effective against all four strains.

The primary study endpoint for the phase III trial was efficacy against any dengue, of any severity, caused by any DENV type in either dengue immune or non-immune recipients. Within 12 months of the second dose vaccine efficacy was 80.2%.

At the 18-month timepoint, vaccine efficacy against all dengue in dengue immune recipients was 76.1% and 66.2% in dengue non-immune recipients. Efficacy against hospitalized dengue was 90.4% and 85.9% against dengue hemorrhagic fever (DHF) (WHO, 1997 criteria). 

More recently, the Instituto Butantan, U.S. NIH, and Merck (MSD) reported the first results from a phase III trial in Brazil with over 16,000 participants and at least two years of disease surveillance.

EFFICACY:

Overall efficacy was 79.6% with dengue immunes having higher efficacy (89.2%) compared to dengue non-immunes (75.3%).

Efficacy data is only available for DENV-1 (89.5%) and DENV-2 (69.6%) due to the low circulation of types DENV-3 and -4 during the trial.

DENV type specific data by dengue immune status reveals higher efficacy against DENV-1 in dengue immunes (96.8%) compared to non-immunes (85.5%) and similar findings for DENV-2 (immune 83.6%, non-immune 57.9%).

There were no severe cases or cases with clinical warning signs reported. The trial will continue until 2024 leaving open the possibility there will be sufficient cases caused by DENV-3 and -4 to gain a clearer view of vaccine performance against these types.