Merck ups the stakes in pneumococcal jab face-off with Pfizer


Dominance of the pneumococcal vaccine category is a race between Merck & Co and Pfizer, and while the latter is comfortably in front at the moment with its Prevnar franchise, Merck has multiple runners in the running.

One of these – dubbed V116 – is a cocktail of 21 Streptococcus pneumoniae serotypes designed to have the most benefit in adult populations, and it has just cleared a phase 1/2 trial as it embarks on a phase 3 programme.

It's a companion shot to Merck's Vaxneuvance (formerly V114), which covers 15 serotypes and was approved by the FDA last year as a rival to Pfizer's Prevnar 13 and newer Prevnar 20 vaccines, which cover 13 and 20 serotypes, respectively.

Merck also sells an older shot called Pneumovax 23, which covers 23 serotypes but is based on an older polysaccharide technology that does not stimulate the immune response as strongly as the newer conjugate vaccines.

The company is adopting a "portfolio strategy" to pneumococcal disease, with "tailored…vaccines to meet the specific needs of different populations," said Dr Eliav Barr, the drugmaker's chief medical officer. It is also working on another shot, V117, which takes a similar approach for the paediatric population.

V116 was compared to Pneumovax 23 in its phase 1/2 trial, and was at least as effective as the older shot against all the serotypes they have in common 30 days after immunisation, with better responses against the strains not included in the older shot.

The new vaccine has already started its first late-stage trials. And earlier this year, it picked up a breakthrough designation from the FDA for the prevention of invasive disease and pneumonia caused by serotypes 3, 6A/C, 7F, 8, 9N, 10A, 11A, 12F, 15A, 15B/C, 16F, 17F, 19A, 20, 22F, 23A, 23B, 24F, 31, 33F, 35B in adults 18 years of age and older.

That list includes eight serotypes not included in any currently licensed pneumococcal vaccine, said Merck, which reported the results today at the International Symposium on Pneumococci and Pneumococcal Diseases (ISPPD) in Toronto.

Those eight strains account for more than 30% of the disease burden caused by S pneumoniae, said the drugmaker.

Prior to COVID-19, pneumococcal vaccines were the largest vaccine market worldwide – estimated at around $8 billion – with Prevnar capturing almost $6 billion of that total in 2020 from its use in both the adult and paediatric categories.

Sales dipped to $5.2 billion in 2021, though Pfizer said the decline was caused by unfavourable timing of government purchases for paediatric immunisation campaigns and disruptions to healthcare caused by the pandemic.  That view seems to have been born out by a bounceback in sales in the first quarter of this year to more than $1.5 billion.