Following the SARS outbreak in 2002 and 2003, nearly two years passedbetween when researchers first decoded the virus’ genetic sequence to when an experimental vaccine was put into a Phase 1 study
By contrast, Inovio needed less than 90 days to design its vaccine, conduct preclinical tests and manufacture initial doses for trials. Moderna moved even faster, readying its prototype in 63 days from when it first selected the genetic sequence around which it would build its treatment.
The speed at which Inovio, Moderna and CanSino are working is enabled in large part by the technology behind the vaccines each is making. Rather than the protein-based vaccines which make up most of medicine’s preventive toolkit, the biotechs are building their vaccines from the genetic building blocks of viruses, RNA and DNA.
Inovio’s, for example, was constructed first on a computer, composed from selected snippets of double-stranded DNA that the company hopes will spur cells to produce proteins capable of eliciting an immune response from the body. Once trained, the immune system could then recognize and respond to an invading pathogen like SARS-CoV-2, as the new coronavirus is known.
Moderna’s vaccine works similarly, but uses messenger RNA encased in lipid nanoparticles to accomplish the task, while CanSino relies on an inactivated virus to deliver its DNA instructions.
First trials of experimental SARS-CoV-2 gene-based vaccines
|First in humans?
|First data expected?
|By early summer
|By early summer
|By year end
Developers of DNA- or mRNA-based vaccines are moving more quickly into clinical testing than would be expected for traditional vaccine approaches. Gene-based vaccines are comparatively unproven, however.
While Inovio and Moderna have tested their technology in several thousand healthy volunteers and patients for programs aimed at other diseases, neither has delivered late-stage study results or secured an approval.
“It’s far from certain that these new platforms will be scalable or that existing capacity can produce sufficient quantities of vaccine fast enough,” wrote researchers at the Coalition for Epidemic Preparedness Innovations, a Norway-based group that’s funded both Inovio’s and Moderna’s efforts to develop a vaccine for SARS-CoV-2.
“It’s therefore critical that vaccines also be developed using tried-and-true methods, even if they may take longer to enter clinical trials or to result in large numbers of doses.”
U.S. government officials, such as National Institute of Allergy and Infectious Diseases Director Anthony Fauci, have repeatedly stressed it will take 12 to 18 moths for a vaccine to be ready for widespread use. Past experience suggests that’s a best case scenario, but the current pandemic could become a proving ground for technologies like Moderna’s and Inovio’s.