The Coronavirus: Did we need a vaccine?
Every aspect of the Coronavirus disease 19 (COVID-19) pandemic has occurred at record speeds, from disease transmission to vaccine development. COVID-19, caused by a novel coronavirus known as SARS-CoV-2, targets the respiratory system. Most people experience flu-like symptoms; however, in the elderly and those with comorbidities, mild respiratory issues can quickly progress to Acute Respiratory Distress Syndrome, resulting in multiple organ failure and death.
The highly contagious nature of this virus, which is spread through droplets and aerosols released when an infected person sneezes or coughs, is evident by the fact that over 106 million COVID-19 cases have been reported worldwide. Over 2.35 million people have already succumb to the virus1–3.
The limitations of hospital capacity, ventilators, and healthcare personnel have been constant concerns throughout this pandemic. Worldwide regulations promoting social distancing and hygiene have prevented transmission, but they have also crippled the economy and stifled social freedoms1,2.
The overwhelming nature of this pandemic has led to the development of COVID-19 vaccines within an unprecedented timeframe. Despite the relief that this brings to some, many are concerned about the effects of the vaccine. A poll conducted by The Associated Press-NORC Center for Public Affairs research reported that of the 20% of Americans that did not want the COVID-19 vaccine, 70% were concerned about side effects4. Furthermore, the speed with which the COVID-19 vaccines were developed have left many questioning whether proper precautions and protocols are still being implemented. The Food and Drug Association (FDA) has stated that vaccine production will be in accordance with legal and regulatory guidelines5.
A cancer patient, who’s immune system is likely compromised by the effects of chemotherapy, would be understandably concerned about the virus and possible risks associated with the vaccine. This article aims to provide insight into the COVID-19 vaccine, concerns for cancer patients, and recommendations of healthcare professionals.
The COVID-19 vaccine: development, efficacy, and side effects
A vaccine is considered effective when it reduces the infection rate, disease severity, or disease transmission. One of the main goals of a vaccination strategy is to create herd immunity, which is a large population of people that are immune to a specific disease6. With the aid of new vaccine development technologies, human clinical trials for the first potential COVID-19 vaccine began on March 16th 2020, just 4 months following the outbreak7. On February 10th 2021, the New York Times Coronavirus Vaccine Tracker reported that 69 COVID-19 vaccines were in the human clinical trial phase8.
Vaccine development was previously a 10-15 year process, and had the COVID-19 vaccines been made in this manner, scientists would still be the exploratory phase of the development process9. Soon after the COVID-19 outbreak in China, scientists unraveled the genetic code for SARS-CoV-2, which serves as the blueprint for the virus’s structure10.Then, by studying the virus’s structure, a protein called the spike protein was found on the outer surface of SARS-CoV-2. Researchers found that SARS-CoV-2 uses the spike protein to bind to and enter human cells, where it can replicate and cause sickness11. The spike protein is now the main target for COVID-19 vaccines12.
Traditionally, vaccines contained a weak or inactivated form of a virus that would allow the body to train against a weakened opponent so it would be better prepared to fight the same virus during an actual infection13. The COVID-19 vaccine was developed using RNA technology, an idea that was introduced in the 90’s by French researchers14. An RNA vaccine contains an mRNA sequence, which is simply a refined version of the blueprint used to build a particular protein. Once in the body, cells can process this code to produce the protein. If this is a viral protein, the body recognizes it as foreign, and the immune system is trained to eliminate it. Some COVID-19 vaccines introduce the code for the spike protein so that the body will be trained to fight it when presented with the actual virus13. Two of the leading COVID-19 vaccines, BNT162b2 Pfizer-BioNTech and mRNA-1273 Moderna, which have been approved for emergency use in the U.S. and E.U., are mRNA vaccines that target this spike protein8,15. COVID-19 vaccines may require periodic updates, similar to the Influenza vaccine, in order to accommodate mutations16.
The Centers for disease control and prevention (CDC) reports a 94.1% efficacy with the Moderna vaccine based on 1 large Phase III clinical trial with 30,000 participants aged 18-95 that had not previously tested positive for COVID-19. Systemic adverse effects, described as mild to moderate, were more common after the 2nd dose. These effects were more severe in patients under 6517. Pain, swelling, and redness were reported as localized reactogenicity symptoms, while chills, fatigue, and headaches were listed as systemic adverse effects18. The World Health Organization (WHO) reported that the Moderna vaccine is safe in patients with comorbidities, such as hypertension or diabetes, and chronic infections, provided that their condition is stable and controlled. Due to the possibility of severe allergic reactions, vaccinees must be monitored for 15 minutes after administration. They also report that the effect on immunocompromised people has not been properly investigated. Persons who have previously tested positive for COVID-19 are not deterred from getting vaccinated, but are advised to wait 6 months19.
Both the Moderna and Pfizer vaccine require 2 doses for maximal efficacy. The New England Journal of Medicine reported 95% efficacy in persons that received both doses of the Pfizer vaccine and 52% efficacy is expected after the 1st dose20. A recent report from Israel described a 33% reduction in COVID-19 cases after the first dose. It is important to consider that the Israeli report is based on persons over 60 years, whereas the original Pfizer study included young people as well21. The Pfizer Emmergency Use Authorization Fact Sheet reports similar side effects to that of Moderna, and immunocompromised patients are asked to report their conditions beforehand22.
The COVID-19 vaccine: considerations for cancer patients
Due to the heterogeneity in cancer patients, there has been some debate as to whether they should be considered a high-risk group. Morbidity and mortality rates between 5 and 61% have been reported in cancer patients that contract COVID-1923. The immunosuppressive effect of many cancer treatments make cancer patients more susceptible to infection. One literature review reported that 10/11 studies in COVID-19 patients reported higher fatalities in patients that also had cancer, especially hematological cancers. Such data argues that cancer patients should be also receive priority vaccination23,24.
Data concerning the effect of the COVID-19 vaccine in cancer patients is very scarce. Of the nearly 44,000 participants in the Pfizer clinical trial only 3.7% were cancer patients23. The immunosuppression in cancer patients caused by chemotherapy, radiation, and/or targeted therapy is also expected to reduce the efficacy of the vaccine. The goal of a vaccination is to elicit an immune response that will train the immune system to fight against a particular disease. A weakened immune system is less likely to respond to this challenge and may therefore be incapable of being trained25. Some have tried to compare the COVID-19 vaccine to the Influenza vaccine; however, studies reporting the vaccine efficacy in cancer patients who received the flu vaccine show that the outcome depends on the cancer type and treatment26–28.
Dr. Nora Disis, a medical oncologist and the director of the Institute of Translational Health and the Cancer Vaccine Institute at the University of Washington, suggests that vaccine dosage and the timing are points of concern, especially in patients in active treatment. She also suggested that cancer patients avoid vaccinations containing an active form of the virus as this could lead to infection in immunocompromised patients29.
Recommendations and reminders for cancer patients
Currently, no COVID-19 vaccines containing live virus have been approved for administration, therefore there should be no risk of becoming infected by the vaccine itself29. As studies of the vaccine in cancer patients are lacking, it is uncertain if cancer patients are susceptible to side effects other than those reported in the general population. The overall recommendation for cancer patients is to receive the vaccine as the risk of contracting the virus is far greater than the possibility of the vaccine being less effective30. We recommend that patients actively on treatment discuss with their oncologist the timing of vaccine administration.
Dr. Jeffrey Farma, a surgical oncologist at the Fox Chase Cancer Center in Pennsylvania, recommends that cancer patients with upcoming surgeries schedule enough time between surgery and the vaccination. Furthermore, patients that have undergone a bone marrow transplant should consult with their hematologist to determine when their immune system will be able to respond to the vaccine. All cancer patients or survivors should consult with their physicians before getting vaccinated31.
Time will tell if current COVID-19 vaccines provide long-term protection and whether they are effective against new variants. Therefore, the advice given to all vaccination recipients is to continue adhering to social distancing and hygiene regulations. Cancer patients, especially, should continue to protect themselves from unnecessary exposure to COVID-19 and any other diseases32,33.
Dr Juneja joins Maryland Oncology Hematology’s White Oak Cancer Center after 13 years of practice in Northern Virginia and Bethesda. He has subspecialized in breast, gastrointestinal, lymphoma, and myeloma in his prior practices. He is very interested in clinical research and cutting edge as well as precision medicine. Previously, he has designed clinical trials with Bristol Myers Squibb, been a medical officer at the FDA, and has been an investigator in several clinical trials.
Having survived cancer himself, he completely understands what it is like to be a patient. He lives with his wife, 2 children, dog, and enjoys playing piano, tennis, running, bicycling, and sailing.
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- COVID-19 situation update worldwide, as of week 5, updated 11 February 2021. https://www.ecdc.europa.eu/en/geographical-distribution-2019-ncov-cases.
- Expectations for a COVID-19 Vaccine – AP-NORC. https://apnorc.org/projects/expectations-for-a-covid-19-vaccine/.
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- Hodgson, S. H. et al. What defines an efficacious COVID-19 vaccine? A review of the challenges assessing the clinical efficacy of vaccines against SARS-CoV-2. The Lancet Infectious Diseases vol. 21 e26–e35 (2021).
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- Zimmer, C., Corum, J. & Wee, S.-L. Covid-19 Vaccine Tracker Updates: The Latest – The New York Times. https://www.nytimes.com/interactive/2020/science/coronavirus-vaccine-tracker.html.
- Government Accountability Office, U. GAO-20-583SP, Science & Tech Spotlight: COVID-19 Vaccine Development.
- Zhou, P. et al. A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature 579, 270–273 (2020).
- Ou, X. et al. Characterization of spike glycoprotein of SARS-CoV-2 on virus entry and its immune cross-reactivity with SARS-CoV. Nat. Commun. 11, 1–12 (2020).
- Mahase, E. How the Oxford-AstraZeneca covid-19 vaccine was made. The BMJ vol. 372 (2021).
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- Oliver, S. E. et al. The Advisory Committee on Immunization Practices’ Interim Recommendation for Use of Pfizer-BioNTech COVID-19 Vaccine — United States, December 2020. MMWR. Morb. Mortal. Wkly. Rep. 69, 1922–1924 (2020).
- Information about the Moderna COVID-19 Vaccine | CDC. https://www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines/Moderna.html.
- The Moderna COVID-19 (mRNA-1273) vaccine: what you need to know. https://www.who.int/news-room/feature-stories/detail/the-moderna-covid-19-mrna-1273-vaccine-what-you-need-to-know?gclid=Cj0KCQiAyJOBBhDCARIsAJG2h5fDy4YPD3cz69Fqiff3ooH4F3065k93kC60SksUGHs-gU62LA16z38aAi6ZEALw_wcB.
- Polack, F. P. et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N. Engl. J. Med. 383, 2603–2615 (2020).
- Mahase, E. Covid-19: Reports from Israel suggest one dose of Pfizer vaccine could be less effective than expected. BMJ 372, n217 (2021).
- Inc, P. Pfizer COVID-19 Vaccine EUA Fact Sheet for Recipients and Caregivers. www.cvdvaccine.com.
- Ribas, A. et al. Priority COVID-19 Vaccination for Patients with Cancer while Vaccine Supply Is Limited. Cancer Discov. 11, 233–236 (2021).
- ASH-ASTCT COVID-19 and Vaccines: Frequently Asked Questions – Hematology.org. https://www.hematology.org/covid-19/ash-astct-covid-19-and-vaccines.
- Yap, T. A. et al. SARS-CoV-2 vaccination and phase 1 cancer clinical trials. Lancet Oncol. 0, (2021).
- Ayoola, A. et al. Efficacy of influenza vaccine (Fluvax) in cancer patients on treatment: a prospective single arm, open-label study. Support. Care Cancer 28, 5411–5417 (2020).
- Zhang, L. et al. Clinical characteristics of COVID-19-infected cancer patients: a retrospective case study in three hospitals within Wuhan, China. Ann. Oncol. 31, 894–901 (2020).
- Yri, O. E. et al. Rituximab blocks protective serologic response to influenza A (H1N1) 2009 vaccination in lymphoma patients during or within 6 months after treatment. Blood 118, 6769–6771 (2011).
- COVID-19 Vaccines and Cancer Patients: 4 Things to Know. https://www.medscape.com/viewarticle/942907.
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- COVID-19 Vaccines: Here is What Cancer Patients and Survivors Need to Know Now | Fox Chase Cancer Center – Philadelphia, PA. https://www.foxchase.org/blog/covid-19-vaccines-here-is-what-cancer-patients-and-survivors-need-to-know-now.
- What cancer patients need to know about COVID-19 vaccines | CTCA. https://www.cancercenter.com/community/blog/2020/12/covid-vaccine-cancer-patients.
- Oncologists can allay COVID-19 vaccination concerns of patients with cancer, survivors. https://www.healio.com/news/hematology-oncology/20210208/oncologists-can-allay-covid19-vaccination-concerns-of-patients-with-cancer-survivors.