Wall Street analysts told clients this development has sparked vast uncertainty across the biotechnology sector. 

The 70-year-old Kennedy has been a longtime health advocate, and Trump said he would let Kennedy "go wild" should he win the November 5 election.

"He's going to help make America healthy again. … He wants to do some things, and we're going to let him get to it," Trump said during his victory speech.

However, making America healthy again will require a complete overhaul of the FDA and USDA. Kennedy could dismantle the longstanding cozy relationships between big pharma and the federal government during Trump's second term. This very prospect spooked vaccine stocks in premarket trading in New York, extending losses from Thursday.

US Premarket: 

Moderna (-2.2%), Novavax (-2.6%) and BioNTech (-2.1%) extended losses from Thursday's decline

EU Cash: 

In Europe, shares of European vaccine makers such as Sanofi and GSK traded lower

"Healthcare/Pharma in focus this morning (GSXEPHAR), following Robert F Kennedy being confirmed as Trump's nominee for health secretary which sparked a pharma and specifically vaccine makers sell off into the close yesterday. To this point, Kennedy has been vocal on vaccines in the past, seen as one of the most prominent anti-vaxxer's in the US. Hence witnessing a -3sd move in our Pharma basket," Goldman's Martin Ehigiator told clients on Friday morning.

Deutsche Bank analyst Emmanuel Papadakis told clients this morning that his team slashed GSK's rating to "Hold" following the news. 

"We consider vaccines to be amongst the greatest scientific achievements to impact public health: unfortunately this view is not shared by the nominee," Papadakis said. 

Kennedy's track record of questioning experimental mRNA vaccines and taking on government bureaucracies overseeing the vaccine industry has caught the attention of many Americans...