Vaccines in Development: Which are Ready for Prime Time?

Vaccine development for COVID-19 is a fast-moving topic. Private industry, academics, and government agencies are working together at rapid speed to generate viable options for billions of people throughout the world without sacrificing safety or introducing unforeseen risk. The goal, as with any vaccine, is to stimulate your immune system to make antibodies against the SARS-COV-2 virus, thereby protecting you from getting sick with coronavirus. The urgency to control the spread has translated into testing of well-known, theoretical, and brand-new technologies. Brilliant minds are hard at work, around the clock, to not only design and test vaccines, but to also determine systems for distribution and administration to help abate the global crisis

There are hundreds of vaccines in the pipeline in various stages of investigation, including 54 (as of this writing) that have advanced to the stage of being tested on people and 10 in late stage (known as Phase III) clinical testing. As of November 2020, there are two that stand out as close to acceptable levels of effectiveness and safety; therefore, plans for mass production, distribution and administration are also underway.

Pfizer and Moderna Both use mRNA Technology

The news that has grabbed recent worldwide attention include announcements by Moderna and Pfizer/BioNTech that Phase III clinical trials of their mRNA vaccine candidates show nearly 95% effectiveness. Many drained global citizens are starting to imagine solutions for this pandemic. Dr. Anthony Fauci, Director of the United States (U.S.) National Institute of Allergy and Infectious Diseases (NIAID) went so far as to claim that “it’s not going to be a pandemic for a lot longer because I believe the vaccines are going to turn that around.”

There are many caveats and precautions to keep in mind, however, not only with vaccine development and confirmation of efficacy and safety, but also with distribution and administration of the shots.

Vaccine Safety & Effectiveness

While these encouraging results bring us closer to a solution, it’s important to understand what they mean. In clinical trials, such as those conducted by scientists at Pfizer and Moderna, there are two groups of people, neither of whom have been previously infected with COVID-19. Participants are randomly assigned to receive injection of either placebo (consisting of saline water) or the experimental vaccine candidate. The participants, doctors, and healthcare providers administering the injection do not know who received vaccine and who received placebo; this is called a randomized, controlled, blinded clinical trial. In medicine, we refer to that design as the “gold standard” of research because we can rely on the results being scientifically valid, rather than the positive effects being from nothing more than luck or chance. Those who received the experimental vaccine in both the Pfizer and the Moderna studies were 90 to 95% less likely to develop coronavirus than those who received placebo injections. For example, in the Pfizer investigation, 170 people, out of almost 44,000 recipients have contracted the virus to date; 162 of them had received placebo, while only 8 had received the vaccine. 

This is promising and exciting. After many months of being sequestered and feeling secluded, we have legitimate reason to feel hope.

After many months of being sequestered and feeling secluded, we have legitimate reason to feel hope.

Now, Pfizer/BioNTech submitted an application for Emergency Use Authorization (EUA) to the U.S. Food and Drug Administration (FDA). The company will continue ongoing research to assess long term immunity (meaning – for how long the vaccine can protect you from contracting the virus), potential negative effects that might occur over time, and ability to confer immunity following exposure to the virus. The last question will explore whether the vaccine is protective if you receive it after you’ve been around someone who has COVID-19. One important element already determined is that it takes roughly 28 days following the second dose of the Pfizer mRNA vaccine until antibodies develop – a crucial step toward conferring immunity. 

Moderna also announced progress on their vaccine, which is based on a similar genetic platform and suggests excellent rates of potential protection.

Vaccine Distribution & Administration

As rates of infection in parts of America and Europe approach their highest levels, everyone eagerly awaits the release of this vaccine. Once authorized by the FDA, public distribution will be complicated and will limit return to our pre-pandemic lives, as will outstanding questions about safety and effectiveness. 

Widespread vaccination in America is still many months away. We must remain vigilant, continue to do everything in our individual and collective power to slow the spread of the virus. Wearing masks, physically distancing, avoiding social gatherings, and practicing hygiene remain the mainstay for stopping the spread of COVID-19 and saving lives. This will be the case for a significant period of time, even after a vaccine is available. Dr. Fauci estimates that high-risk Americans and healthcare workers will be among the first recipients of the vaccine. Ambitious estimates suggest that a sizeable proportion of the U.S. population will receive the vaccine by mid to late spring. But, Dr. Fauci warns, such a “guesstimate” assumes that everything proceeds without setbacks, mistakes, or unanticipated risks.

But, Dr. Fauci warns, such a “guesstimate” assumes that everything proceeds without setbacks, mistakes, or unanticipated risks

Concerns have also been raised about how Pfizer will manufacture and ship the vaccine to hospitals and pharmacies across the globe. Pfizer is manufacturing the vaccine in Kalamazoo Michigan and in Belgium; for Americans, the majority of vaccine doses will come from the Great Lakes state. It is up to federal and state governments, however, to decide to whom to appropriate the doses and the number to request. As mentioned, the vaccine preparation uses mRNA that, once inside your body, enters cells and is coded to produce a protein that mimics spikes on the outside of the coronavirus. These spike proteins “trick” your immune system into responding to this foreign entity as if it were coronavirus. 

The mRNA needs to be kept at temperatures well below zero (more specifically, negative 70 degrees Celsius, which is equivalent to negative 94 degrees Fahrenheit); otherwise, the vaccine will denature (fall apart) and be rendered ineffective and unusable. Pfizer has designed reusable boxes filled with dry ice to keep the vials of vaccine cold enough, and shipping companies, including UPS and FedEx, have designed special compartments to send and deliver the vaccine vials. These special containers hold between 1000 and 5000 vials. 

One potential advantage of the Moderna candidate, which relies on similar mRNA and, therefore, still requires cold storage, is that the temperatures needed for this vaccine to stay stable up to 30 days resemble standard refrigerators and freezers available in pharmacies and hospitals.

Many details are yet to be determined, including that Pfizer reports the plan to ship 50 million doses in December. Twenty-five million of those vials are slated for distribution in the U.S., while the other 25 million will go to other countries. That means that 12.5 million Americans can be vaccinated during this first round, since each person receives two doses, three weeks apart. 

12.5 million Americans can be vaccinated during this first round, since each person receives two doses, three weeks apart. 

Meanwhile, the Bill & Melinda Gates Foundation is at the forefront of global distribution, working with international partners to both quickly develop the second generation of vaccines more suitable for low and moderate income countries and prepare systems for distribution. GAVI, Vaccine Alliance and Coalition for Epidemic Preparedness Innovations (CEPI) are co-leading the efforts of the Access to COVID-19 Tools (ACT) Accelerator to ensure equitable access to COVID-19 tests, treatments, and vaccines. As Melinda Gates says “COVID-19 anywhere is COVID-19 everywhere.”

As Melinda Gates says “COVID-19 anywhere is COVID-19 everywhere.

Distribution Within States’ Purview; But Dollars Fall Short

In the U.S., the logistics of vaccinating and tracking millions of citizens will be left largely to state governments. The Centers for Disease Control and Prevention (CDC) in the U.S. has committed to providing 340 million dollars to the states for these distribution efforts; however, local health departments anticipate much higher costs and have requested another 8.4 billion dollars from the U.S. Congress to adequately and appropriately fulfill this duty. Comprehensive online systems are necessary to keep track of who has received vaccinations. Insufficient funding will slow down the rate of vaccination, especially among citizens who are hard to reach, as well as the process of following who has received their first and second doses. States with large rural populations pose particular challenges for the administration of the vaccine due to the cold storage requirements.

States with large rural populations pose particular challenges for the administration of the vaccine due to the cold storage requirements.

Each of Us Has a Role in Curbing COVID-19

Another problem involves potential resistance to taking the vaccine. There is a worldwide movement of anti-vaxxers, which is based on false data and amplified by social media. Plus, others feel some degree of skepticism because of the speed with which the vaccines are being developed. 

But, as Kavita Patel, MD, a prominent physician and public health expert, points out “vaccines don’t save lives; vaccinations do.” 

Kavita Patel, MD, a prominent physician and public health expert, points out “vaccines don’t save lives; vaccinations do.”

Lessons from the Past

When Elvis Presley was vaccinated on national television in 1956, the polio immunization rate among teens skyrocketed and incidents of polio went down by 90% in just four years. History shows that when prominent Americans, especially from marginalized or high-risk communities, use their platforms to lead by example, people pay attention and heed their advice. Nowadays, those messages can reach far and wide through social media influencers, when first vetted by public health experts. 

Many questions remain unanswered and unexpected challenges will arise along the way. The aim is for scientists and authorities to work hand-in-hand to mitigate polarization and to not only produce safe, effective vaccines but also readily distribute and administer them as swiftly, efficiently, and equitably as possible. 

In the meantime, our job as citizens remains to limit the spread of COVID-19 even after the vaccine is available and distribution has begun. This virus will circulate in the population for a long time to come. Like a mantra, we say again and again:  wear masks, physically distance, avoid social gatherings, and practice hygiene. Plus, while availability of testing has improved, progress is still needed for widespread application in the U.S. and receipt of rapid results. As we face the last quarter of the year since COVID-19 was identified, we still need to set testing as a top priority by enhancing supplies and, perhaps, the possibility of self-administered home testing. 

Written By Rohan Prabhu & Jacki Hart, MD

White House Touts Old Therapy for New Virus

Convalescent plasma (CP) is not a new therapy, but it’s gotten new attention. For illness that has progressed to respiratory distress, physicians in hospitals have prescribed convalescent plasma for COVID-19 patients, along with other treatments like steroids and antiviral medications that are generally well established for this clinical scenario from similar infectious agents. Because of both theoretical benefit and observational success, studies have begun to emerge about the application of convalescent plasma for COVID-19 specifically. With early encouraging results suggesting improved survival rates for tens of thousands of individuals, the White House administration urged the United States (U.S.) Food and Drug Administration (FDA) to establish emergency use authorization (EUA). Despite the preliminary success, this move remains controversial because the usual degree of research scrutiny has not been applied to convalescent plasma for COVID-19. Studies are ongoing.

Proponents say convalescent plasma has been around for a long time for similar purposes, what could be the harm? (Well – think hydroxychloroquine…) Skeptics say the move is premature. The middle ground would have been to continue in the previous capacity of FDA investigational (also called compassionate) use. That allows doctors to make informed clinical decisions to use CP when the patients’ circumstances warrant, with documentation and agreement that the patient is aware of the experimental nature of the therapy, and with meticulous tracking of many details that would become clinically relevant and inform well-substantiated application of the treatment as we move forward. 

Now, some experts worry that the EUA might jeopardize research. Having the medication readily available for this purpose may translate to fewer people enrolling in studies since doctors can obtain the drug for patients without requesting the added demands of participating in a clinical trial. Given the positive publicity about convalescent plasma, patients may not take the chance of being assigned to a placebo group and, thus, not receive the therapy. The EUA may also lead to diminished tracking which helps delineate important details regarding the treatment, like dosing and timing of administration as well as potential risks, side effects, and negative reactions.

How does Convalescent Plasma Work?

The idea of convalescent plasma is to gather blood from patients who have recovered from the infection and, thus, developed antibodies that might confer immunity to someone who currently has the illness. In theory, the antibody-rich blood product should help patients recover faster from COVID-19. Since there is no confirmed effective treatment for COVID-19, the idea of boosting patients’ immune response to the virus seems worthwhile.

The therapy has been around since early in the 20th century and has been used successfully for other viruses, including hepatitis, mumps, measles, rabies, polio, and the 1918 influenza pandemic. More recently, it’s even been used for H1N1 flu, Ebola, and previous coronavirus outbreaks like Severe Acute Respiratory Syndrome -1 (SARS-1) and Middle Eastern Respiratory Syndrome (MERS). However, it remains unclear whether convalescent plasma adds benefit to standard treatment. The way to determine this involves studies using a rigorous design known as randomized controlled clinical trials (RCTs) for hospitalized patients with COVID-19.

Without such scientific analysis, many questions remain unresolved about the proper way to administer the therapy

Without such scientific analysis, many questions remain unresolved about the proper way to administer the therapy – including exactly who will benefit, at what stage of the COVID-19 infection, and what dose confers protection. 

Data from Chinese researchers suggests benefits like xray resolution of lung infections from COVID-19, a reduced viral load, and improved survival. However, the data is extremely limited, including that that study was discontinued due to low rates of enrollment and lack of added clinical benefit from convalescent plasma. There are several assessments going on currently in the U.S., including through the University of North Carolina (UNC) and an expanded (again, called compassionate) use program led by the Mayo Clinic in Minnesota. The latter is from where much of the information about CP use in COVID-19 patients has been derived to date. 

In the meantime, under what appears to be possible pressure from the White House Administration, and against the advice of some prominent experts, the FDA issued the EUA on August 23rd, 2020 for convalescent plasma. 

Given the change in FDA status, there has been a surging interest from hospitals continuing to struggle with high numbers of people with COVID-19. This has translated to accelerated demand for convalescent plasma. Blood banks around the country are shipping CP to states like Florida, Texas, Tennessee, Mississippi, Missouri, and California. Organizations leading these efforts include the Red Cross and America’s Blood Centers.

If you’ve recovered from coronavirus and test positive for COVID-19 antibodies, you might be eligible to donate convalescent plasma; the FDA explains.

If you’ve recovered from coronavirus and test positive for COVID-19 antibodies, you might be eligible to donate convalescent plasma; the FDA explains. Even one donor can benefit three to four patients with matching blood types. 

Written By Rohan Prabhu & Jacki Hart, MD