Merck looks past Sanofi's dengue woes in development deal with Brazilian vaccine institute

Merck entered a new collaboration with Brazil's Butantan Institute to advance dengue vaccines. (Merck)

Even after Sanofi suffered a costly dengue vaccine controversy last year, fellow pharma giant Merck & Co. isn’t backing away from the field. Instead, it has struck a new partnership with Brazil’s Butantan Institute to advance their respective dengue vaccine programs.

Each partner has a dengue vaccine in development, and now they’ll share “clinical data and other learnings.” Merck agreed to pay the Butantan Institute $26 million upfront and up to $75 million if its vaccine candidate meets various development and commercialization milestones, plus potential royalties on sales.

Merck's vaccine is in phase 1 testing, a spokeswoman said, while the Butantan Institute's candidate, TV003, is in phase 3.

Both vaccines are made up of four live attenuated viruses, one from each dengue serotype, Merck's spokeswoman said. The technology was originally developed at the National Institutes of Health. The Butantan Institute is aiming to enroll 17,000 participants at 15 Brazilian cities for its late-stage trial.

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If Merck's vaccine wins approvals, the company will commercialize the shot around the world, excluding Brazil. The Butantan Institute will retain the right to manufacture and sell its vaccine in its home country.

The partnership comes after Sanofi's world-first dengue vaccine tripped into a high-profile safety controversy. Analysts initially thought Sanofi’s Dengvaxia could pull in blockbuster sales, but the launch sputtered and then suffered further after Sanofi disclosed the vaccine could cause more serious dengue cases if given to people who haven’t had a prior infection.

The revelation triggered outrage in the Philippines, where the vaccine had been part of a mass vaccination campaign. Officials stopped vaccinations, started investigations and demanded refunds. All told, the episode cost Sanofi €158 million last year, the company reported.

RELATED: Sanofi's dengue shot Dengvaxia wins FDA priority review despite controversial past

The controversy may have cost Sanofi even more in lost sales. In 2016, executives said the vaccine could deliver €200 million in first-year sales. Instead, 2016 Dengvaxia sales rang in at €55 million. In 2017, that figure sank to €3 million.

But while the situation in the Philippines marked a setback for Sanofi, the company isn’t giving up on Dengvaxia; it's now seeking U.S. and European approval. The vaccine has already secured more than 20 approvals worldwide.

Meanwhile, Takeda has a phase 3 candidate in testing as well. The Japanese drugmaker last year hit its massive trial enrollment goal, and at the time, program head Derek Wallace told FiercePharma that the trial "represents the confidence we have in our dengue vaccine candidate and in Takeda’s capacity to develop it.”