Takeda’s chances of stealing a march on rival Sanofi in the dengue fever vaccine market look increasingly high after encouraging data from a phase II trial.
Takeda’s dengue candidate TAK-003 showed a high protective efficacy rate in the DEN-204 trial, achieving a 71% reduction in the risk of developing symptomatic dengue compared to placebo in children and adolescents.
Phase III trials of Dengvaxia showed a 61% reduction in the risk of developing dengue fever, and while phase II findings can often be truncated in larger-scale studies the new data suggests Takeda’s programme is on track.
Meanwhile, TAK-003 induced sustained antibody responses against all four serotypes of dengue virus, regardless of previous dengue exposure and dosing schedule, in contrast to Dengvaxia which showed some variation in response rates to different serotypes in trials. Takeda’s candidate is now in a phase III trial due to generate results before the end of next year.
“We are seeing an acceptable safety profile and sustained antibody responses out to 18 months in this trial,” said Derek Wallace, who is leading the TAK-003 development programme at Takeda. “The reduced incidence of dengue in children and adolescents receiving TAK-003 is encouraging, however data from our ongoing Phase 3 efficacy trial, TIDES, are required to confirm these findings.”
Dengvaxia was approved at the end of 2015 but has suffered from a painfully slow take-up, which the company has blamed on political turmoil in some of the key markets where dengue fever is endemic, including Latin America and the Philippines.
Sales of the vaccine last year were €55m, well short of the €200m forecast, and seem to have gone into reverse this year with Sanofi booking just €22m for the product in the first nine months and €4m in the third quarter. Once tipped to make €1bn-plus at peak, consensus analyst estimates have been rapidly dialled back and Thomson Reuters is now predicting €360m in sales in 2022.
Takeda is hoping to leapfrog Sanofi in the sector, and last year announced a €100m investment programme in a manufacturing facility in Singen, Germany, to make sure it has plenty of production capacity for TAK-003 if approved.
Dengue is the fastest spreading mosquito-borne viral disease and 40% of the world’s population lives under the threat of the virus, according to the World Health Organization (WHO).
The disease infects 390 million people a year and symptoms include fever, a hammering headache, flu-like symptoms, bone, muscle and joint pain, rash and nausea and vomiting.
While most patients recover, the disease poses a considerable economic burden on society – it is estimated to cost India upwards of $500m a year for example – and causes around 20,000 deaths a year worldwide.