In late 2020, results from large clinical trials gave us great hope regarding vaccines that can prevent infection by the SARS-CoV-2 coronavirus that causes COVID-19. The two vaccines that have been approved in the U.S. are a type called mRNA vaccines.
As the software of life, DNA encodes the information necessary to make proteins, whether it’s in a human, a plant, or a single-cell bacterium. But for that code to work, it must first be converted into a molecule called messenger RNA, or mRNA. These mRNA molecules deliver the information to cellular machinery called ribosomes, which then work to make proteins.
With mRNA vaccines, scientists engineer an mRNA molecule that encodes the proteins that we want the immune system to target. In the case of SARS-CoV-2, these mRNA vaccines are designed to target the surface spike protein that the virus uses to enter our cells.
No live virus is involved, nor are components necessary to assemble new versions of the virus. Just a description of what a specific marker on the surface of the virus looks like. This teaches the immune system, which then launches a broad response involving a variety of cells and antibodies. Thus far, these spike-targeting mRNA vaccines have proven quite successful.
Despite these breakthroughs, the battle isn’t over yet. COVID-19 still prevents a very real danger, and certain people—like those with cancer—are especially vulnerable.
The scientific and medical communities have tackled COVID in part by leveraging recent breakthroughs in the field of cancer immunotherapy, as was highlighted in our June livestream event. Since then, we have learned even more, and we now have better ways to prevent and treat it, and a much better understanding of how it affects people with cancer. The situation and our knowledge continue to evolve, but already we’ve uncovered many important pieces of information that can help save lives.
Here, we share our experts’ insights regarding key questions about cancer, COVID-19, and vaccination. Most of these conversations come from our recent CRI Virtual Immunotherapy Patient Summit, and full videos of all the event sessions can be watched on YouTube.
One of the most pressing questions is how having cancer affects people’s susceptibility to COVID-19. While patients aren’t necessarily more likely to catch COVID-19, they do appear more likely to suffer serious disease if they do.
“When COVID first started, there was a lot of concern that the outcomes of cancer patients who develop COVID would be substantially worse than the general public,” noted Scott Kopetz, M.D., Ph.D., a colorectal cancer expert from the University of Texas MD Anderson Cancer Center. “And I think we do see that the risks are slightly higher, but they're nowhere near as draconian a risk as we thought initially.”
“Cancer patients in general are definitely more susceptible to severe disease. Meaning if they get the virus, they're more likely to have more complications,” added Trisha Wise-Draper, M.D., Ph.D., a head and neck cancer expert from the University of Cincinnati College of Medicine.
“There are two important reasons for this,” according to Kunle Odunsi, M.D., Ph.D., a gynecologic cancer expert from the Roswell Park Comprehensive Cancer Center who addressed the topic during a recent CRI webinar.
"Cancer by itself can affect the immune system. And the weaker your immune system, the less likely you are able to fight any infection, whether it's COVID-19 or any other form of infection,” he explained. “The second potential reason why cancer patients are more likely to have severe COVID-19 compared with other patients is because many of the cancer therapies, such as chemotherapies, also affect the immune system. And when they affect the ability of the immune system to fight infection then, as you can imagine, the patients can be sicker and have more serious effects from COVID-19.”
“Based on what we know so far, most cancer patients are not at higher risk [of catching COVID-19] as long as they're not immunocompromised,” noted Elizabeth M. Jaffee, M.D., a pancreatic cancer expert from the Johns Hopkins University School of Medicine, during the Summit. “If you're not on high doses of chemotherapy, if you haven't had a bone marrow transplant, if you're not immunocompromised, then you're like anyone else when it comes to COVID.”
Still, giving chemotherapy to treat cancer is the right choice sometimes, despite the risks.
“If you have curable disease and we're recommending chemotherapy and radiation to treat you, the risk of you dying of cancer is much higher than getting COVID-19,” Wise-Draper emphasized. “We are absolutely not saying don't get treated. If you see you have cancer, you need to listen to your physicians and make sure you get your treatment.”
“I know that I can cure a lot of head and neck cancers,” she continued, “so, I'm going to give you the treatment that's recommended, because I'm not going to sacrifice the chance of curing you. But I am going to tell you to please protect yourself, stay away from people, wear your mask, don't go to big events.”
Importantly, in contrast to chemotherapy, immunotherapy hasn’t been found to confer any similar increase in risk with respect to COVID-19.
“We do not have to stop immunotherapy to prevent a patient from getting COVID. We don't know that being on immunotherapy helps, but it certainly doesn't hurt and make you more susceptible,” said Jaffee.
“If they are receiving these classes of immunotherapy drugs, generally speaking, they are safe,” added Saby George, M.D., a kidney cancer expert from the Roswell Park Comprehensive Cancer Center. “But if somebody's needing high-dose steroid [which can dampen the immune system] for the management of these side effects, then it becomes very tricky. That's when they may be more susceptible to infections like this.”
Experts also believe that having cancer in no way prevents people from benefiting from the new COVID-19 vaccines.
“If you have a normal immune system, not immunocompromised, you should do well with the COVID vaccine,” advised Jaffee. “Just like you would get a flu shot, if you're eligible for a flu shot, you're eligible for the COVID vaccine. From what I understand from [National Institute of Allergy and Infectious Diseases Director] Dr. Fauci, there has been no evidence of safety risks. I do believe the FDA will make sure that they're looking at all of the data. That's why it's taking a little bit longer. But again, you want to ask your oncologist.”
“All of these vaccines are looking incredibly effective,” affirmed Philip D. Greenberg, M.D., a blood cancer expert from the Fred Hutchinson Cancer Research Center. “SARS-CoV-2 turned out to be a remarkably easy target to develop an effective immune response to.”
As far as which vaccine to get, Greenberg said not to stress.
“If you can get a vaccine, I don't think it's worth worrying about waiting for any particular one of them. You get the vaccine you can get right now because they are going to be in short supply for the first six to eight months. If it turns out that one of them gives a better, more durable, long lasting response, you can always get boosted with a different vaccine later.”
Though we have a lot to learn about the long-term immunity that results from becoming infected, people who have already dealt with the disease should still plan to get a vaccine.
“Even if you got COVID-19, you should still get vaccinated because you actually produce a better protective antibody response to the vaccine than you do if you get it naturally, which goes a little against what we're used to. Part of that is probably because part of the virus is making you immunosuppressed and not able to mount a response to it. So, I absolutely recommend, especially to our immunosuppressed cancer patients, that they get this vaccine.”
In addition to its other impacts, COVID-19 dramatically changed how cancer research is conducted and how care is provided. This proved challenging in the beginning, and led to the eventual stoppage of more than 1,000 clinical trials, according to an analysis by the CRI Clinical Accelerator team.
“Cancer centers, unfortunately, had to figure out how to deal with this during the initial peak,” said Greenberg. “For a while, patients were not being enrolled on new trials because of that, until we could figure it out how to do this safely. What you can feel comfortable with is that everyone who is based at a cancer center now is going through very routine testing to make sure that they're incapable of transmitting [the virus]. But they're also wearing protective gear, which makes it virtually impossible to transmit it.”
“I can assure you that all these centers have now had unfortunately all too much time to figure out how to effectively deliver care in a way that doesn't put patients at risk. That allows patients who are at risk to feel safe. It allows those patients who, unfortunately, have contracted the infection to still be able to receive care.”
Fortunately, technology—particularly in the form of telemedicine or telehealth—has helped ease some of the troubles associated with this new (for now) normal.
”It's more convenient for patients during treatment, whether it's experimental or not,” Jaffee explained.
“Often, we see patients just to make sure they're not having any side effects from the therapies. And so, doing a telemedicine visit makes a lot of sense, because it's a check in, you see the patient, the patient can ask questions, you can answer them. And, they don't have to be inconvenienced by coming to the hospital. Of course, when you need blood work, those sorts of things, we still need you to come to the hospital. It's going to be a hybrid long-term of trying to make it more convenient for patients when it's safe to do that. But also, of course, we want to see patients when it's necessary to see them.”
Wise-Draper echoed that concern.
“I don't want my patients coming in unless they have to. We're doing a lot more telehealth if they're able to. If they're not getting treatment, I'm asking that we just talk over the phone. Don't come to the ER, unless you absolutely have to. Call me first so that we can go over your symptoms and maybe see you in our clinic where it's a little safer.”
According to George, these added cautions are often nothing new for people with cancer, whom he trusts with the responsibility.
“My experience is that patients are very smart,” he said. “They try to stay away from trouble. Very few [cancer] patients have become sick in the past year from COVID. So I hope all the patients are very careful, and they take care of themselves during this time, particularly until we have control over COVID.”
Learn more about CRI's work related to COVID-19