Experts say they’re not sure yet how effective COVID-19 vaccines are for people with cancer. Evgeniy Shkolenko/Getty Images
  • Experts are uncertain how effective COVID-19 vaccines are for people being treated for cancer and those who have survived the disease.
  • One reason is that people with cancer have not been included in COVID-19 vaccine trials.
  • Some studies have indicated there’s some immune response for people with cancer after a COVID-19 vaccination, but the reaction might not be as strong as it is in the general population.

Since the COVID-19 vaccine clinical trials began, people being treated for cancer and those who have survived the disease have been largely excluded.

Two prominent cancer organizations are now insisting this must change.

In a joint statement, the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research (FCR) announced that individuals with active cancer or a history of cancer must be made eligible for COVID-19 vaccine trials unless there is a safety justification for exclusion.

“We’ve learned that patients with cancer are especially vulnerable to severe illness, hospitalization, or death due to COVID-19,” Dr. Everett E. Vokes, president of ASCO, said in the joint statement.

“However, since clinical trials for COVID-19 vaccines have largely excluded patients with cancer, we still have a long way to go to better understand how safe and effective COVID-19 vaccines are for patients in active treatment,” he added.

Dr. Julie Gralow, chief medical officer of ASCO and a medical breast cancer oncologist for 30 years, told Healthline that there is a great need to learn more about how cancer and the novel coronavirus interact.

“Early in the development of the vaccines, it, of course, made sense to try to get healthy population to start within these trials,” Gralow said.

“But once you have positive signals, once you have locked that in, it is supercritical to adjust eligibility in subsequent trials or expand cohorts to more vulnerable and underserved populations, including those who are not healthy,” she added.

Gralow said that because these trials to date enrolled narrower, more homogenous patient populations, many of the most vulnerable and underserved people don’t know if the vaccines are safe or effective for them. 

She said ASCO has begun to collect data over the past couple of months on people with cancer and the COVID-19 vaccines.

“The vast majority, including patients with solid tumors, have good immune responses to the vaccines,” Gralow said. “But we are finding high-risk populations, including in hematological malignancies: B cell malignancies, lymphoma, multiple myeloma. Some of them have a response, but they are generally at lower levels.”

People with blood cancers who are being treated with the drug Rituxan have particularly low response rates to the vaccine, according to Gralow.

“It’s not zero. But it’s low,” she said. “We are also seeing this with CAR-T cell immunotherapies and stem cell transplants. But in regular chemo, we have not seen any big problems.”

The importance of trial access

Gralow noted that ASCO’s statement is simply a continuation of the organization’s outreach this past year to underserved populations.

“We are using this statement mainly to remind people that we need to be inclusive, we need to make sure we are adding various underserved racial populations, for example, and older populations to clinical trials, and others who have been underrepresented,” she said.

Dr. Erin Reid, a hematologist and professor of medicine at Moores Cancer Center at UC San Diego Health (UCSD), agrees with the ASCO/FCR position.

“Formally studying the safety and benefits of SARS-CoV-2 vaccination in individuals with cancer is desirable on many fronts, and I agree with the ASCO/Friends of Cancer Research joint statement,” she said.

Reid said UCSD and many other institutions have been participating in the CCC-19 registry, which follows outcomes in people with cancer who developed COVID-19.

“There is probably a lot of variability between different individuals with cancer and response to vaccines — even among people who received the same treatment for the same cancer,” Reid said. “Bottom line: Some immune protection is better than none.”

Vaccination of someone who is immunocompromised is likely to provide reduced severity of COVID-19 if that person is exposed to SARS-CoV-2 after vaccination, Reid concluded, but “the degree of protection compared to someone with a normal immune system is not known.”

Looking at immune responses

An analysis published in the journal The Lancet reports that immune responses to COVID-19 vaccines are more robust in the non-cancer population but that there is still some degree of response among people with cancer.

In people with cancer, one dose of the Pfizer/BioNTech vaccine “yields poor efficacy. Immunogenicity increased significantly in patients with solid cancer within 2 weeks of a vaccine boost at day 21 after the first dose. These data support prioritization of patients with cancer for an early (day 21) second dose of the vaccine.”

Meanwhile, Gralow says that ASCO and FCR continue to look at other ways to embrace inclusiveness and keep reaching out to cancer patients and others who are not properly represented.

“We have much to learn about each different group, and COVID has only magnified the problems with access to clinical trials and healthcare in general,” Gralow said.

For people who’ve fought cancer, the uncertainty is more than an annoyance.

Alec Kupelian, 26, an operations specialist at Teen Cancer America who lives in Portland, Oregon, had a sarcoma tumor that required 11 months of chemotherapy plus radiation.

He’s in remission and remains actively involved in cancer causes.

He’s angry that people with cancer have not yet been allowed to enter vaccine trials.

“There is nothing scarier than uncertainty,” Kupelian told Healthline. “My experience with cancer has left me with strong anxieties. Cancer patients need to be allowed in COVID-19 vaccine trials. We need to know how the vaccines are working for us.”

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