Study: Cancer immune therapies linked to severe COVID-19

Cancer patients treated with medicines that unleash the immune system to attack tumors are more likely to be hospitalized with respiratory complications from COVID-19, according to a new study.

The findings suggest that while immune therapies known as checkpoint inhibitors - a class that includes Merck & Co.'s blockbuster Keytruda and Bristol-Myers Squibb Co.'s Opdivo - may increase the risk of developing severe coronavirus symptoms, other treatments like chemotherapy may not. People suffering from advanced cancer or having had recent surgery also didn't appear to get more seriously ill, according to data published in the journal Nature Medicine on Wednesday.

The research seeks to shed more light on the link between COVID-19 and cancer. Although previous studies from China and Italy suggested a higher death rate, little is known about the connection between the two illnesses and the impact of various medicines, the authors wrote. Of the almost 9,400 deaths of people diagnosed with the new virus in New York state as of April 10, about 8% were patients with cancer, they said.

Treatment with checkpoint inhibitors "was an independent predictor of severe respiratory illness," authors including Mini Kamboj, a doctor at Memorial Sloan Kettering Cancer Center, said in a statement accompanying the research.

"Until further evidence is available, it is prudent not to alter treatment decisions but to consider increased vigilance with SARS CoV-2 testing in patients initiating or continuing treatment" with immune therapies, according to the research.

The study found 40% of a group of more than 420 patients at the New York cancer center diagnosed with COVID-19 were hospitalized, a fifth developed severe respiratory illness and 12% died within 30 days. That case-fatality rate is lower than previous estimates, according to the authors. More research in larger patient populations is needed to identify risks, they said.