For Dennis Carson, however, the FDA announcement represented the culmination of a scientific odyssey that took 21 years. To him, vaccines represent a paradigm in preventive health—even though vaccines take longer to develop and typically don’t bring the kind of financial payoffs that blockbuster drugs yield in the life sciences industry.
Carson, a 71-year-old professor emeritus at the UC San Diego School of Medicine, co-founded Dynavax in 1996 with the idea of developing a new hepatitis B vaccine based on short bacterial DNA sequences. The intended result would provoke a stronger and longer-lasting immune response, and Carson says that has been borne out. It may have been a long slog to win FDA approval, but “It hasn’t been a long slog because the science was wrong,” he said.
The recombinant vaccine, known commercially as Heplisav-B, is the first Dynavax product to win FDA approval, and the first new hepatitis B vaccine in the United States in more than 25 years.
The underlying idea, based on research led by Carson and UC San Diego’s Eyal Raz, is that “immunostimulatory DNA,” serving as the adjuvant in recombinant biologic vaccines, would be a kind of interchangeable part in an array of new vaccines. The idea is only now coming into its own. Carson, who still operates a lab at the Sanford Consortium for Regenerative Medicine, says similar DNA sequences could some day be used in other vaccines to stimulate an immune response to tuberculosis, malaria, flu, and even cancer.
Dynavax is now conducting trials of cancer vaccines based on immunostimulatory DNA oligonucleotides. The selected agents are injected directly into the tumors (for melanoma and head and neck cancers), or given by inhalation (in lung cancer).
Getting this far in hepatitis B, though, has required the patience of Job.
As a point of comparison, it took 13 years to win FDA approval for the chemotherapy drug 2-CdA (Cladribine), which Carson helped develop with Ernest Beutler, his mentor at The Scripps Research Institute. Yet in his office, which overlooks the Torrey Pines Golf Course and the Pacific Ocean, Carson takes a serene view.
“Twenty [plus] years sounds like a long time,” he said. “But for a vaccine that is given to a lot of people, and where safety is the prime issue, it takes a long time.”
Dynavax initially submitted its … Next Page »