Recent announcements by the pharmaceutical companies Pfizer and Moderna have raised hopes that effective vaccines against the COVID-19 virus will soon be available. Memorial Sloan Kettering infectious disease specialist Monika Shah discusses how these vaccines work and how people, including those with cancer, will be able to get one.
How do these new vaccines work?
Like all vaccines, the two developed by Pfizer and Moderna stimulate the immune system to produce antibodies against a virus, in this case the COVID-19 virus, which is called SARS-CoV-2. Results reported so far have been very impressive — more than 90% effective.Back to top
What made it possible for them to be produced and tested so quickly?
The new vaccines use what’s called messenger RNA technology. This type of vaccine is faster and cheaper to make than conventional vaccines, so it takes less time to be able to test them in a large enough group of people. Another reason they were able to get results so fast is we’re in the middle of a pandemic, and there have been lots of people who have been exposed to the virus who are available and willing to be vaccinated in the setting of these large clinical trials.Back to top
When will the vaccines be available, and how will they be distributed?
A limited amount of vaccines may be available by the end of the year if the required FDA standards for efficacy, safety, and manufacturing are met. The vaccine can be distributed only after an FDA approval or emergency-use authorization. It’s hard to say precisely when MSK will have it, but we are taking every possible step to acquire vaccine doses. The vaccines must first be distributed to New York State, which then allocates them to hospitals and other distribution facilities that apply for them.
We don’t know how many doses will be available in the short term, but MSK plans to prioritize who receives the vaccines in alignment with the guidelines of the Centers for Disease Control and Prevention. This is a phased approach, where the first people to receive them are healthcare workers and first responders, followed by older people and those with high-risk medical conditions. It will be several months or more before we have a vaccine for everyone.Back to top
What would you say to someone who is reluctant to take a new vaccine?
There’s always going to be a perceived risk with vaccines for some people. But the data shared from the preliminary analysis of the phase III trials of the two COVID-19 vaccines suggest they were not just effective, but also safe. The side effects are like what you see with other vaccinations — injection site pain, fatigue, and the occasional fever that resolved within one to two days. Vaccines are critical components of the public health strategy to mitigate and eventually eradicate infectious diseases. The vaccine may be new, but this strategy is long-standing. Vaccine campaigns have repeatedly proven successful when people participate.
For most people with cancer, we will likely recommend that they get the vaccine when it is available, regardless of the type of treatment they are receiving. Although cancer treatment may reduce the effectiveness of vaccines, we believe the COVID-19 vaccine is safe and could offer important protection for cancer patients, who may be at higher risk for complications from COVID-19. Of course, we are constantly monitoring the data and safety profile of these vaccines as more people receive them, and will communicate updates as more information becomes available.Back to top