When it comes to COVID-19 vaccines, cancer patients shouldn’t feel like they have to be choosy. With the recent rollout of a third COVID-19 vaccine, patients may wonder if one vaccine is better than the other, especially since they employ two different types of technology. Also, news reports that the new Johnson & Johnson (J&J) vaccine may not be as effective as the two other vaccines has also raised concerns.
But Dr. Mashiul Chowdhury, Infectious Disease Program Specialist at Cancer Treatment Centers of America®,(CTCA), says all three current vaccines are safe and effective, and cancer patients should get whatever vaccine they can, when they can. “No one vaccine is better for cancer patients over the other one,” he says.
How are they different?
The vaccines currently available to protect against COVID-19 use two different types of medical technology and have different dosage rules and storage requirements. Here’s a rundown:
mRNA vaccines
The Pfizer and Moderna vaccines were created using pioneering messenger ribonucleic acid (mRNA) technology. These vaccines use engineered strands of mRNA to send instruction to the immune system to produce antibodies that target spike proteins protruding from the outside of the coronavirus cells. These spike proteins allow the virus to attach themselves to cells and spread the infection.
While they use the same technology, the two mRNA vaccines have some minor differences:
Pfizer-BioNTech: This vaccine is approved for those 16 or older. It’s given in two doses, three weeks apart.
Moderna: This vaccine is approved for those 18 or older. It’s given in two doses, four weeks apart.
The two vaccines have proven to be up to 95 percent effective in preventing serious infections from COVID-19.
Viral vector vaccines
The J&J vaccine is more traditional. It uses a modified form of a different kind of virus, a viral vector, to send instructions to the immune system—in this case, a form of an adenovirus, which is similar to coronaviruses is used. Both adenoviruses and coronaviruses, in different forms, are responsible for many common colds. Once inside the body, the vaccine produces a harmless COVID-19 lookalike, which prompts the immune system to produce antibodies that’ll also work against the real thing.
The J&J vaccine is 66 to 72 percent effective at preventing moderate to severe symptoms from COVID-19, but researchers say the lower efficacy may have been influenced by different clinical trial results in different countries and the presence of virus variants that did not exist when the Pfizer and Moderna viruses were tested. All three vaccines are between 85 and 95 percent effective at preventing severe symptoms and hospitalizations.
Regardless of the difference in efficacy rates, Dr. Chowdhury stresses that cancer patients should not wait for an mRNA vaccine if the J&J version is all that’s available to them.
“Although the efficacy may be different, we shouldn’t wait for one particular vaccine,” he says. “We need to take whatever is most available, because all vaccines are equally effective in preventing severe disease and death.”
The J&J vaccine has two advantages over the mRNA vaccines:
- It only requires one dose instead of two.
- It does not require deep-freeze cold storage that creates the shipping and storage challenges posed by the mRNA vaccines.
White House Chief Medical Advisor Anthony Fauci, MD, Director of the National Institute of Allergy and Infectious Diseases has already been vaccinated. But, he said, he would not hesitate to receive any of the three vaccines currently approved. “All three of them are really quite good, and people should take the one that’s most available to them,” Dr. Fauci says on NBC’s Meet the Press. “If you go to a place and you have J&J, and that’s the one that’s available now, I would take it,” Fauci said. “I personally would do the same thing. I think people need to get vaccinated as quickly and as expeditiously as possible.”
Made to wait
The federal government supervises the distribution of COVID-19 vaccines. States do not control which approved vaccines they receive, but they do determine who receives them.
Cancer patients and long-term survivors are at very high risk of severe symptoms and death from COVID-19. Cancer and its treatments may damage the immune system, allowing the virus to spread more quickly. The U.S. Centers for Disease Control and Prevention has recommended all Americans 16 and older with underlying medical conditions, such as cancer, diabetes and heart disease, get priority when vaccines are distributed. Still, some states have chosen not to put cancer patients high on their priority lists.
Last month, more than 130 cancer care centers, research centers, advocacy groups and other organizations penned an open letter to President Joe Biden, urging him to pressure states to prioritize the more than 17 million U.S. cancer survivors for vaccination.
“We want to again emphasize the importance of ensuring that prioritization of vaccine supplies be given to high-risk populations that include patients with active cancer and survivors of cancer,” the letter states. “We sincerely hope that you and your colleagues in the administration will stress to all State Public Health Departments that patients with active cancer and survivors of cancer must be provided priority access to a lifesaving COVID-19 vaccine.”
