Vaccine race: Volunteers step up to help test promising candidates
Bay Area residents this week join the global race for a coronavirus vaccine, with developers of two of the most promising candidates seeking hundreds of volunteers in San Francisco, Oakland and Santa Clara County.
Kaiser Permanente enrolled its first Northern California participants in a global clinical trial for a vaccine made by Pfizer and the German technology company BioNTech on Monday. In San Francisco, researchers with UCSF and the Department of Public Health expect to start giving volunteers a vaccine made by
AstraZeneca and Oxford University next week.
Sutter Health’s East Bay AIDS Center, located at Alta Bates Summit Medical Center in Oakland, also expects to join the AstraZeneca trial.
Both experimental vaccines are entering Phase 3 trials, the last step before federal approval, assuming the products prove safe and effective. In all, about 1,400 Bay Area participants are expected to be enrolled in both trials, but given the speed at which vaccine development is happening, scientists expect to seek many more hundreds, if not thousands, of volunteers in the coming months.
“This pandemic has had a huge negative impact on every aspect of society and our daily lives. It’s caused so much pain and suffering. To be able to be part of the solution is tremendously exciting,” said Dr. Susan Buchbinder, colead investigator of the Bay Area’s AstraZeneca vaccine trials and director of Bridge HIV, the San Francisco public health HIV prevention unit.
“Even though we’re going to be testing AstraZeneca, we anticipate we’ll be part of other trials as well,” she said. “I would be thrilled if any of the vaccines are successful. I’m rooting for all of them.”
Global vaccine development has moved at explosive speeds since the new coronavirus was identified in early January. More than 100 products are being studied, and dozens have been tested in humans.
The coronavirus has spread far and fast around the world, infecting more than 20 million people, including 5 million in the U.S., and killing 745,000 globally. Many infectious disease experts believe that vaccines are the best, and perhaps only, hope for ending the pandemic and rebuilding economies shattered by social restrictions without even more devastating loss of life.
The United States has identified five vaccine candidates it considers most viable. In addition to the Pfizer and AstraZeneca vaccines, the U.S. is betting on products made by Johnson & Johnson, Merck and Moderna. The Pfizer, AstraZeneca and Moderna vaccines all are in Phase 3 trials, collectively planning to enroll nearly 100,000 volunteers worldwide.
The U.S. Department of Health and Human Services already has awarded up to $1.95 billion to Pfizer to start manufacturing 100 million doses of vaccine and up to $1.2 billion to AstraZeneca for 300 million doses. Manufacturing vaccines while they are still being tested is risky, but the hope is they could be given to the public right away if they prove safe and effective.
“These are heroic efforts, truly noble efforts to fight this pandemic,” said Dr. Bali Pulendran, a vaccine specialist at Stanford Health Care. “And I think it’s wonderful that these premier Bay Area institutions are playing a very active role in this effort.”
Both the AstraZeneca and Pfizer trials are doubleblind and placebocontrolled, which means some participants will be given the vaccine and others a placebo. All participants will be given two doses via injection, one month apart. Neither participants nor researchers will know who got the vaccine.
The trials will last two years, but investigators expect to have early results within a few months. The AstraZeneca trial is part of the National Institutes of Health COVID Prevention Network. People can sign up online to participate at coronavirusprevention network.org. The Pfizer trial is sponsored by the vaccine developers. Only Kaiser members can join the study in California for now.
The goal in both trials is to determine whether the vaccines prevent people from getting COVID19, the disease caused by the new coronavirus. The studies also will look at the longterm safety of the vaccines, and whether the vaccines trigger a strong immune response and prevent infection altogether. Early studies of both vaccines found them to be safe, causing only mild, shortterm symptoms such as fatigue or body aches in some volunteers.
The vaccine trials brought to the Bay Area are tapping into existing research networks that have been used for decades to study immunization efforts for HIV and a variety of other infectious diseases.
“In some ways (the trial) very much looks like the type of vaccine trials we do all the time. What really is not typical is the speed at which all of this has taken place,” said Dr. Nicola Klein, director of the Kaiser Permanente Vaccine Study Center and lead investigator for the trial in Northern California, which is enrolling participants in Santa Clara County and Sacramento.
Networks like the ones at Kaiser and in San Francisco employ dozens of researchers and health care providers with years of critical experience in running clinical trials, which can be complex and expensive. These networks already have nurses who are familiar with explaining complicated science and medical terms to prospective volunteers, for example, and analysts who know how to collect data and process it to protect the doubleblind protocol.
The AstraZeneca vaccine trial is using San Francisco’s extensive HIV clinical trial network, which dates to the 1990s and has contributed to HIV vaccine research along with prevention and treatment studies.
An HIV vaccine has proven frustratingly elusive after nearly 40 years of research. But scientists said there’s reason to be hopeful that a coronavirus vaccine — or more likely multiple vaccines — is close at hand.
For starters, most people are able to naturally fend off the coronavirus without serious illness, as evidenced by the millions of people worldwide who have been infected and have no symptoms or mild disease and fully recover without treatment. That’s not the case with HIV.
That means the human immune system already is built to attack the coronavirus — a vaccine just needs to
harness and boost that response.
“Yes, HIV has stymied us, but the coronavirus is very new and uncharted territory, and there’s a lot of reason to be enthusiastic,” said Dr. Annie Luetkemeyer, who is leading the AstraZeneca trial at UCSF. “It’s great to leverage these experienced clinical trial networks in an area that’s new to all of us, which is COVID research. It’s a good way to not start from scratch.”
As with the Kaiser trial, the San Francisco study plans to enroll people who are most at risk of infection and of serious illness, including people who are older, have underlying health issues, or work in jobs where they face greater risk of exposure to the virus.
Luetkemeyer and other infectious disease experts said it’s critical that multiple vaccines using different technologies are studied at once. Not all of them will be successful, and some vaccines may be more appropriate for different groups of people. For example, one vaccine may work well in people over age 60 while another may not work at all in that age group.
The Pfizer and AstraZeneca vaccines use different technologies for triggering an immune response. The Pfizer vaccine delivers synthetic genetic material, called messenger RNA or mRNA, to prime the body’s immune system to develop cells and antibodies to attack the virus. It’s a new approach to immunization that has never before been used in a vaccine. Moderna also uses the mRNA approach.
The AstraZeneca vaccine, developed with scientists at Oxford University, uses a chimpanzee adenovirus — essentially a virus that causes the common cold in chimps — to deliver a small segment of the coronavirus to humans. The adenovirus, weakened so it can’t harm humans, is tagged with the coronavirus segment, specifically a protein found on the “spikes” on the surface of the virus. The immune system attacks the adenovirus and develops antibodies and other defenses specific to the coronavirus.
Both vaccines have been shown to prompt a doublebarreled immune response: antibodies that neutralize the coronavirus to prevent it from infecting human cells, and immune cells that stop the virus from replicating once it’s already invaded. Scientists don’t yet know if one response is more important, or if both are necessary to develop immunity.
It’s also not known how long immunity might last, assuming the vaccines work. The Food and Drug Administration has said any vaccine needs to be at least 50% effective in order to be considered for approval.
Dusta Eisenman, a pediatric nurse at Kaiser Santa Clara, was given her first dose in the Pfizer study Wednesday morning. She said that though she’s “a little nervous” to be one of the first participants in the trial, “I’m pushing that down for the greater good.”
“I understand it’s warp speed and it’s going really fast, but we’ve dedicated a lot of smart people to this. I’m putting my trust into that,” she said. “To be able to feel like I’m contributing something now, and maybe there’s a light at the end of the tunnel, that’s exciting for me. I’m trying to be a light for friends and others who are feeling hopeless at this point.”