The race to find a vaccine for COVID-19 is going full tilt.
More than a hundred are in the pipeline.
Pfizer is even ramping up production of its product, in case it's successful.
Historically, only about 6% of vaccine candidates make it to market.
This time around, researchers are working on every avenue - RNA, DNA, viral vectors, live proteins, nanoparticles and more.
"By having that diverse array of different technologies, it increases the likelihood that you'll get one or two or three that will reach the finish line," says Dr. Peter Hotez, a vaccine developer and researcher at the Baylor College of Medicine.
Moderna, the maker of the first vaccine to go into human testing is expanding tests into elderly volunteers.
Initially, trials were limited to 18 to 55-year-olds.
Researchers say we should beware of companies reporting rosy results - chances are it's aimed at their investors.
More than 100 candidates in race for coronavirus vaccine