COVID-19 Alaska Clinical Update

November 17, 2020

AK cases

23,240 cases total in residents; 548 hospitalizations total and 98 deaths. Currently, 121 Alaskans are hospitalized with COVID-19, comprising 14% of statewide inpatient beds in hospitals, and 14 are requiring mechanical ventilation. Alaska has been in an acceleration phase with cases rising for seven consecutive weeks.

What you really need to know about the COVID-19 vaccine

• Safety and efficacy data from COVID-19 vaccine trials will be reviewed by the FDA as well as an independent review board before a vaccine is authorized or approved
• The companies making the leading vaccine candidates (Moderna and Pfizer) have taken the unusual step of releasing their protocols for public review to ensure transparency
• Both Moderna and Pfizer announced promising results from initial planned analyses, meaning the first distribution of vaccines may be weeks away
• Healthcare workers are top priority for the vaccine
• There are no plans to mandate a vaccine
• The State of Alaska is preparing to distribute the vaccine as soon as late November, although the date when the first doses will be available are not yet known
• Distribution may be challenging, since one of the two leading vaccine candidates has to be stored at an extremely cold temperature
• You can help distribute vaccine to your community! See the Alaska COVID-19 Vaccine Information Page for Healthcare Workers to sign up. DHSS is actively seeking providers to enroll in vaccine distribution in all communities.

A refresher on vaccine development: part 1 of 2

As conversation on vaccines ramps up, clinicians may get more and more questions from patients. DHSS developed a multi-part series reviewing the vaccine development process, delving in depth on the different types of vaccines being tested for COVID-19 and where they are in the pipeline, and addressing common questions about vaccines to help clinicians have answers at their fingertips. The first part will discuss the process for approval, while the second part discusses specific vaccine candidates, risks and FAQs. For more information, see the DHSS website on vaccines. To propose corrections or to ask this series to address specific questions, please contact elizabeth.ohlsen@alaska.gov. Please also join us on the DHSS Vaccine ECHO, Thursdays at 2PM: register here. 

How vaccines work

Vaccines induce immunity against a specific disease by conferring active immunity, causing the body to develop antibodies to recognize and attack an antigen. Killed vaccines give the recipient a virus that cannot replicate, while live attenuated vaccines give the recipient a virus that can replicate but has been altered so it does not cause disease. Live attenuated vaccines usually prompt a stronger, longer-term response (MMR and varicella, for example). As a general rule, the more similar a vaccine is to the disease-causing form of the pathogen, the better the immune response to the vaccine. COVID-19 vaccines in Phase 3 trials currently use one of three technologies to provoke an immune response to the spike protein of SARS-CoV-2 by causing a patient’s cells to express membrane spike proteins. One technology, used by the two leading companies, employs lipid particles to deposit mRNA inside cells to be translated into a spike protein that the immune system then reacts to. In another, adenoviruses modified to not cause symptoms carry spike protein code to be transcribed and then translated into a spike protein by host cells. A third technology injects premade spike proteins to directly stimulate antibody production.

The idea with vaccines is to not just protect the person who gets the vaccine but to reduce the spread of the disease in a population. Vaccines protect individuals in several ways- by preventing a person from getting a disease entirely, by making the illness less severe if they do end up getting the disease, and by providing some protection from related strains of a virus since the immune system will recognize the virus as at least somewhat familiar. An example of the last circumstance is the influenza vaccine, which is offered for different strains every year, but people who get the influenza vaccine every year will actually have stacking immunity to a variety of strains and be more protected than they would be if they had only gotten the shot that year. From a population perspective, if enough people get a vaccine, it can make it so difficult for a disease to spread that it nearly goes away or goes away entirely. However, as we have seen with measles, some diseases can come back very quickly if fewer people in a population choose to get a vaccine. 

How vaccines are tested

Any vaccine used in the United States must go through clinical development phases to get approval from the FDA. 

Preclinical testing takes place in animals before a vaccine is tested in humans.

Phase 1 trials consist of small studies involving around 10-100 healthy people. These studies ask two questions- does the vaccine cause any health problems? And does it produce an immune response? Even after these trials are published, data will continue to be collected about any adverse effects in all vaccine recipients.

In Phase 2 trials, hundreds of people who are healthy receive the vaccine as part of one or more randomized controlled trials mainly designed to look for adverse effects. These trials also take a first look at efficacy and determine dosing and schedule. Similar to Phase 1 and Phase 3, after these trials are published, data will continue to be collected about any adverse effects in all vaccine recipients.

In Phase 3 trials, thousands or tens of thousands of people, including people of similar ages and health characteristics to the people the vaccine is intended for, receive the vaccine as part of a randomized controlled trial. These larger studies allow scientists to ask whether rarer side effects are seen and further determine the effectiveness of the vaccine. Phase 3 trials will actively collect data and follow all participants for at least two years. However, adverse effects in Phase 3 trials are generally seen in the first two months after receiving the vaccine.

The FDA also requires monitoring after vaccines are approved and widely used to monitor for any side effects. The FDA notes in their guidance that they may also require formal post-marketing studies or trials to assess known or potential serious risks of COVID-19 vaccines if warranted.

What about an EUA?

An EUA is an Emergency Use Authorization. The FDA has the power to issue an EUA to help respond to a public health emergency by allowing not-yet-approved medical products to be used in a public health emergency when alternatives are not adequate, approved or available. Because the full FDA approval process for a vaccine is typically very time consuming, the FDA may issue an EUA to one or more vaccines if they demonstrate safety and efficacy in clinical trials. The FDA has issued detailed guidelines for applying for an EUA for a COVID-19 vaccine. To get an EUA, a company has to demonstrate that their vaccine is safe and effective through at least one well-designed Phase 3 clinical trial. They also specify that the company is also expected to continue to collect data after an EUA is issued and to apply for full approval as soon as possible. Trials must be far enough along when an EUA is issued that the EUA would not interfere with any other trials needed to get full approval.

How exactly can a COVID-19 vaccine get an EUA?

The FDA has said the minimum data needed to consider an EUA is if the manufacturer can show that at least 50% of the people who get the vaccine are protected from either getting COVID-19 at all or getting COVID-19 bad enough that it causes any symptoms. Also, there must not be any safety concerns where the risks outweigh the benefits of the vaccine.

Part 2 of 2 will cover specific vaccines in development. For more information and to stay up to date on the most current information on vaccine data and distribution plans, join us on the DHSS weekly vaccine ECHO on Thursdays at 2PM.

References and further information

Alaska COVID-19 Vaccine Information
CDC general vaccine information
FDA statement on vaccine approval and guidance document for COVID-19 vaccine development
FDA definition of an EUA and EUA guidelines for a COVID-19 vaccine
CDC guidance for vaccination during a pandemic
The New York Times maintains a vaccine tracker for updates on vaccine status
The Moderna vaccine’s study protocol
The Pfizer vaccine’s study protocol