It’s no secret Sanofi has had trouble with its world-first dengue vaccine, Dengvaxia, but that hasn't dissuaded Takeda. Its own dengue shot met its goal in a pivotal phase 3 study that covered eight countries and more than 20,000 participants.
In a trial dubbed TIDES, the Japanese drugmaker's TAK-003 candidate was effective in preventing dengue fever caused by any of four serotypes. The trial, which enrolled children aged 4 to 16 in dengue-endemic countries in Latin America and Asia, is ongoing, with more data expected to read out later this year, Takeda dengue program head Derek Wallace said in an interview.
These first two sets of data will make up regulatory filings for approval, Wallace said. In the meantime, Takeda is working to build up commercial manufacturing and making other preparations for a potential launch, the company's vaccines chief, Rajeev Venkayya, said in a release.
The placebo-controlled study is testing two doses of the vaccine against any dengue serotype, regardless of whether recipients have had a prior infection. Monday's data—looking at efficacy at the 15-month mark—is the first of three analyses planned for the trial. The company didn’t release detailed efficacy numbers but plans to publish the data in a peer-reviewed journal, Wallace said.
The second part of the study—the set due for release later this year—will include another six months of follow-up, plus data on efficacy by serotype and serostatus. The third portion includes three-year follow-up data.
Takeda’s vaccine is based on a life-attenuated dengue serotype 2 virus, which provides a genetic “backbone” for the shot to fight all four types of the virus, according to the drugmaker.
As Takeda presses forward with its vaccine, the company is no doubt aware of Sanofi’s struggles in the field with Dengvaxia. The French drugmaker won an initial approval for the shot back in 2015 but hasn’t had success in the years since, partly in thanks to a crucial flaw: Dengvaxia can cause more serious cases of dengue if given to people who haven’t had a prior infection.
That, plus the fact that a dengue diagnostic doesn’t exist for field testing, has complicated the shot’s future. A mass vaccination campaign in the Philippines was called off after Sanofi’s safety disclosure.
Sanofi is now working to develop a diagnostic to screen potential recipients, but that's an additional hurdle for mass vaccination efforts. Takeda’s vaccine aims to protect regardless of dengue history, executives have said, which would be a leg up for the shot if it wins approval.
Aside from Sanofi, Takeda could end up facing additional competition in dengue. Merck & Co. last month entered a development deal with Brazil’s Butantan Institute in which the groups will share learnings to aid their respective programs.