Cancer treatments can weaken the immune system, reducing the impact of a Covid vaccination.
These people may need to receive an additional booster shot, according to Saranya Chumsri, MD, haematologist and oncologist at Mayo Clinic Cancer Centre and lead author of the new study.
This applies not only to chemotherapy but also a newer type of cancer treatment that was believed to not be as damaging to the immune system.
Doctor Chumsri’s patients produced lower levels of Covid neutralising antibodies while undergoing treatment at the cancer centre.
Because the immune systems of these people are weakened they are also at greater risk of infection and severe complications from the Coronavirus.
Doctor Chumsri said: “It is important for patients with cancer who are receiving chemotherapy to receive a COVID-19 vaccine.”
Data about vaccines is expected to be released over time that will help medical decision makers.
Earlier this month, US courts ordered the FDA, a regulatory agency, to begin releasing vaccine data it held on Pfizer’s Covid vaccine.
The data is being released at a rate of 55,000 pages a month under the Freedom of Information Act.
The FDA initially argued it would not be able to release more than 500 pages a month.