A much anticipated Covid-19 vaccine, developed by the University of Oxford and AstraZeneca, achieved 70% efficacy in phase III interim data. While less effective on paper, it could prove cheaper and easier to distribute than its most advanced competitors.
Scientists and politicians heartily received the announcement of promising interim clinical trial results from the Covid-19 vaccine being developed by AstraZeneca and the University of Oxford. They come not long after phase III results from the vaccines being developed by BioNTech and Pfizer, Moderna, and the Russian Gamaleya Research Institute.
While the vaccines of BioNTech and Moderna rely on messenger RNA technology, the University of Oxford and AstraZeneca vaccine is based on a common cold virus called adenovirus and engineered so it can’t replicate in human cells. The adenovirus trains the immune system to recognize the virus causing Covid-19 — SARS-CoV-2 — by exposing immune cells to the spike protein on the surface of the virus, which it uses to infect cells.
Compared to the vaccine candidates of BioNTech and Moderna, the technology used in AstraZeneca’s vaccine carries several key advantages. First of all, the technology is well established, whereas there is yet no mRNA medicine approved. Second, the vaccine can be produced, transported, and stored cheaply — its price is at least five times cheaper than its two competitors.
Additionally, the mRNA vaccine candidates have certain temperature requirements that make their transportation and storage more complicated, whereas AstraZeneca’s just requires fridge temperatures.
The data released by the University of Oxford contain an interesting finding. Volunteers given the planned dosing regime — two full doses a month apart — received 62% protection. However, those that mistakenly received half a dose and then a full dose a month later received an impressive 90% protection. All groups analyzed together made an efficacy of 70%.
According to Zoltán Kis, Research Associate in the UK’s Future Vaccine Manufacturing Hub at Imperial College, the final efficacy figure will likely go up when the full data are announced. He speculated that this ‘small dose paradox’ may be partly due to a secondary immune response against the adenovirus used to deliver the vaccine. However, there is no definite explanation; the full clinical trial data are expected to shed more light on this.
The 70% efficacy is, according to Kis, good for a vaccine. But it falls beneath the efficacy of BioNTech and Moderna’s vaccines, which are both over 90%. However, the Oxford candidate seems to perform well in virus transmission prevention and in the reduction of asymptomatic carriers.
A key advantage of mRNA technology is that the development of new vaccines against novel targets — be it new Covid-19 strains or another disease altogether — is way faster than with traditional vaccine development methods.
“One week a facility might be making a polio vaccine, while next week the same facility may be manufacturing a coronavirus vaccine,” Kis noted.
The fact that AstraZeneca’s vaccine originated from the University of Oxford showcases the role of academic-pharma partnerships to tackle healthcare emergencies. “The academic side brings lots of knowledge, lots of innovation,” Kis told me. “Big pharma has the experience to do large-scale clinical trials and make vaccines fast.”
Academic innovation has also been essential to the development of the Covid-19 vaccine contenders from Moderna and the German biotech CureVac, and new ideas in the life sciences sector are primarily generated in universities and research institutes. A phase II-stage RNA vaccine developed by the UK’s Imperial College is another example of how far institutions are progressing in the Covid-19 vaccine race.
Healthcare challenges will not be over when the coronavirus pandemic ends. New pandemics, antibiotic-resistant pathogens, and rare diseases are upcoming challenges that the big pharma alone cannot address. Pharmaceutical companies need to combine their market focus and problem-solving mindset with new technologies and out-of-the-box thinking prevalent in academic groups and startups.
Image from Shutterstock