2. Merck & Co.

Sales of Merck's HPV vaccine Gardasil 9 grew 6% to $2.3 billion in 2017. (Merck)

Merck & Co.
2017 sales:
$6.5 billion
2016 sales: $6.2 billion
Vaccine business led by: Michael Nally

While immuno-oncology star Keytruda has generated plenty of headlines for Merck lately, the company's vaccine business has been on the upswing, too, thanks to human papillomavirus shot Gardasil 9. That shot helped drive a strong 2017 for the unit: The pharma giant's immunizations pulled in $6.5 billion, or 4.8% growth year over year. 

And Gardasil obviously was a big part of that story. Sales for the HPV shot grew 6% to $2.3 billion as U.S. officials continued pushing for more uptake and as its rollout in China picked up steam. Pneumovax 23 also chipped in growth; the polysaccharide pneumococal shot saw a 28% sales boost for the year to $641 million. Merck's established pediatric shots ProQuad, MMR II and Varivax together reached $1.68 billion last year, up 2% over 2016. And its rotavirus vaccine, RotaTeq, grew 5% to $652 million.  

It's not all positive at the company, though. Merck's shingles vaccine Zostavax faces new pressure from GlaxoSmithKline's Shingrix, which has fairly stampeded onto the market. In the fourth quarter, after GSK launched Shingrix, Zostavax sales plummeted 45%. The vaccine tanked again in the first quarter of this year, too, coming in 58% lower than the same period in 2016. Merck’s "other" vaccines—small products not mentioned by name—together slipped 15% to $387 million for all of 2017. 

RELATED: Gardasil grows, Zostavax struggles as Merck posts $6.5B in 2017 vaccine sales 

The company has its eyes on some promising pipeline projects, though: a 15-valent pneumococcal shot, for instance, that aims to fight Pfizer’s megablockbuster Prevnar 13 for share. Merck started a phase 3, head-to-head trial of that candidate, dubbed V114, against the Pfizer shot, now the bestselling vaccine in the world. Offering protection against 13 serotypes of the pneumococcal virus, Prevnar generated $5.6 billion in sales last year.  

Merck R&D head Roger Perlmutter, M.D., Ph.D., sees his company's pipeline shot as an “opportunity to both strengthen the response to serotypes covered by other pneumococcal conjugate vaccines but also to add additional serotypes." But even if Merck can elbow aside Prevnar 13, Pfizer has another challenger in the wings; its 20-valent pneumococcal shot is in midstage testing. 

RELATED: Merck pits its pneumococcal shot against Pfizer's mammoth Prevnar in head-to-head phase 3 

Other Merck candidates include V212, an inactivated varicella zoster vaccine; a hexavalent pediatric shot under review; and a late-stage Ebola shot. The latter has actually been used in the real world already; to fight a deadly Ebola outbreak in the Congo this year, officials deployed the Merck vaccine on an emergency basis and were able to get the outbreak largely under control. 

Life science commercial intelligence firm EvaluatePharma recently predicted Merck's vaccine business will bring in $9.4 billion in sales in 2024, representing 5% annual growth during the period. 

2. Merck & Co.