Like other pharmaceutical and biotech companies, Johnson & Johnson initiated efforts to develop a COVID-19 vaccine as soon as the novel coronavirus sequence became available in January 2020.
At the end of March, Johnson & Johnson announced that its experimental vaccine could be ready for human testing by September 2020, and for regular use shortly thereafter in early 2021.
J&J Uses “Proven” Adenoviral Vector Platform
The COVID-19 vaccines currently in development are all unique. Some, like Moderna’s mRNA vaccine, use newer, experimental technologies. Others, like Johnson & Johnson’s adenoviral vectors, have been proven as a tried-and-true approach over time.
Adenoviral technology has been tested extensively, but it is only used in one commercial vaccine today: the rabies vaccine used to immunize wild animals. The Janssen division of Johnson & Johnson hopes to create the world’s second adenoviral vaccine with its engineered version of adenovirus 26 (Ad26).
Ad26 normally causes common colds, but has been disabled to stop replication. A gene for the surface protein from COVID-19 has been “stitched” into the Ad26 vector. As Paul Stoffels, J&J’s chief scientific officer explains, “We learned from what we did in Zika that with the right [Ad26] vector, we can get very significant immunity. We can do it with one dose, but we’re going to test two doses in the clinic.”
Why Isn’t J&J Launching Clinical Trials Now?
Moderna, Oxford University, and other vaccine leaders are already in the process of completing Phase 1 and Phase 2 clinical studies, but Johnson & Johnson’s Phase 1 trial of its experimental vaccine won’t occur until the fall.
Stoffels explains why J&J believes it’s worth the wait: “With vectors like Ad26, you need to get the seeds [copies of the engineered virus] to do biological manufacturing. That takes time to make sure we select the right clones and that we have a stable selection so we can grow the right ones.”
Although J&J’s clinical trials will lag behind others in the crowded pharmaceuticals field, the company can accelerate its timeline from a Phase 1 trial of safety and immune responses to a proof-of-concept study thanks to its pre-established safety data. “We are used to recruiting extremely fast, so we could do 250, 500 people in a day and month later, 3 days after the blood is taken, we should be able to know the results,” Stoffels elaborates.
Stoffels and the rest of the J&J team envision using thousands of people in an emergency use application of the experimental vaccine in order to achieve a large Phase 2 study in the real world.
Thanks to its landmark new partnership with the Biomedical Advanced Research and Development Authority (BARDA), Johnson & Johnson has committed more than $1 billion of investment to co-fund vaccine research, development, and clinical testing. If all goes as planned, J&J will have a vaccine ready for emergency use by early 2021.