Dengue vaccine rollout nears as Panacea begins final trials

India is moving closer to its own dengue vaccine. Panacea Biotec has begun the final Phase III trials of DengiAll, its dengue vaccine candidate, after a development effort of nearly 15 years. The study is overseen by the Indian Council of Medical Research (ICMR).

More than 10,000 volunteers have enrolled in the trial across the country. The Phase III trials started in 2024, with participants randomly assigned to receive either the vaccine or a placebo, and results are expected later this year. Panacea Biotec will test whether DengiAll protects against all four dengue virus serotypes now circulating in India.

"We will try to get this vaccine out there as soon as possible," Syed Khalid Ali, chief scientific officer of Panacea, told AFP in New Delhi. Ali added: "We will be the second (single-dose) vaccine to come out... But in India and several lower-middle-income countries, we will be the first ones to roll out the dengue vaccine."

Why India needs a dengue vaccine

Dengue causes severe flu-like symptoms and debilitating body aches, and it has exploded globally, fuelled by rising temperatures and densely populated cities. The World Health Organization says almost half the world's population is at risk, with 100 to 400 million infections every year.

India has recorded more than one million dengue cases and at least 1,500 dengue deaths since 2021, according to WHO-linked reporting cited by NDTV. Monsoon outbreaks regularly push Indian hospitals to their limits, crowding urban wards and leaving rural regions grappling with late diagnoses and poor access to care. Doctor Ekta Gupta, professor of clinical virology at the Institute of Liver and Biliary Sciences in New Delhi, said dengue was now considered hyperendemic in India, with all four virus serotypes circulating simultaneously. "This vaccine is very much needed right now to control the occurrence of these cases, or at least prevent the severity," she said.

The field has long struggled with the four-serotype problem. Immunity to one strain does not protect against others, and secondary infections can be more severe. A home-grown shot would cut dependence on imported prevention tools. The figures underline why dengue deaths remain a policy concern.

How the final trials will work

The Phase III trials will measure how well DengiAll prevents symptomatic dengue and hospitalisation among volunteers. Trials of this scale are the last step before a vaccine can seek regulatory approval in India. The ICMR's oversight adds a layer of independent scrutiny to the data. In India, final approval would come from the Drug Controller General of India, while WHO prequalification would be required for large-scale international use.

The candidate is based on a tetravalent strain originally developed by the US National Institutes of Health. Panacea Biotec is the most advanced of three Indian firms licensed to use the strain, having developed its own formulation and secured a process patent. Inside the company's research labs, doctor Priyanka Priyadarsiny, head of biological R&D, said: "We are extremely cautious about purity, safety and adverse effects. Only after meeting regulatory specifications can a product be considered safe for public use." Ali said the shot could be given to people aged one to 60 and is expected to offer long-term protection.

Dengue vaccine competition and next steps

At present, the WHO recommends only one dengue shot, Qdenga, produced by Japan's Takeda for children aged six to 16 in high-transmission settings. Qdenga requires two doses administered three months apart and is not currently available in India. A successful Indian dengue vaccine would give the national immunisation programme a domestic option for the first time. The dengue vaccine rollout in India would then depend on regulatory clearance and manufacturing scale-up. A dengue vaccine rollout across lower-middle-income countries could follow if WHO prequalification is secured.

Virologist Shahid Jameel, an Oxford University fellow not connected with the trial, warned that dengue incidence could rise by 50 to 75 per cent under current climate change trends. He cautioned that only Phase III results would determine whether the candidate meets the criteria for a safe and effective vaccine. "Only then can we have a useful dengue vaccine. It is still early days, but there is hope for the future," he told AFP.