The COVID-19 pandemic has led to understandable anxiety within the blood cancer community about how their illness may affect their ability to overcome COVID-19 infection. Members of the Oxford Centre for Haematology have led a collaborative research project looking at the response of patients with chronic lymphocytic leukaemia (CLL) who were infected with COVID-19, reported in the journal Blood.
CLL is a type of blood cancer, where white blood cells called B lymphocytes grow out of control. The disease is typically slow to develop, showing few symptoms at the beginning. Around 4000 people are diagnosed with CLL each year in the UK, more commonly among people over 60 years old, and there are a variety of treatments available, depending on the stage of disease progression.
In the recent study, investigators from 45 centres selected 374 patients with CLL who were diagnosed with COVID-19 in two time periods (Feb 2020-Apr 2020 and May 2020-Jan 2021). Trends showed that CLL patients diagnosed with COVID-19 in spring 2020 experienced a high case fatality rate (31-33%). At this point the, FDA authorised the use of dexamethasone for COVID-19 infected patients requiring oxygen and a wider set of treatment guidelines were disseminated. The overall trend in overall survival for CLL patients reassuringly mirrors that observed in the general population. There was a definite improvement in survival for patients infected with COVID-19 after May 2020, likely due to improvements in treatment.
Figure 1. Overall survival from the time of COVID-19 diagnosis of (A) the entire cohort and (B) stratified by timing of diagnosis for patients who required oxygen
Further analysis compared the effect of a range of treatments including dexamethasone, remdesivir, convalescent plasma, corticosteroids and hydroxychloroquine in the CLL COVID-19 patient group. Researchers also analysed how long patients required intensive care treatment in hospital, how many needed oxygen, whether their BTKi cancer therapy was continued during COVID infection, and whether there was any correlation of the overall survival rate to age, gender or cumulative illness rating scale.
A final question concerned the efficacy of COVID-19 vaccines to promote an immune response within CLL patients. Serology tests showed that 60% of CLL patients developed COVID-19 antibodies, although the response varied considerably. Ongoing research aims to understand the immune response to COVID-19 vaccination.
“Since the beginning of the COVID-19 pandemic, medical staff have worked very hard to optimise treatment for patients, and it is gratifying to see the improvements in survival of CLL patients to COVID-19 infection” said Dr Toby Eyre, Consultant Haematologist at the Oxford University Hospitals NHS Foundation Trust, and the co-lead of the research project. “Oxford Centre for Haematology, with funding from NIHR Oxford BRC Oxford, is in a strong position to coordinate both retrospective and clinical trials to add to the body of knowledge about how best to treat blood cancer patients during the COVID pandemic.”
Read the research paper.
Find out more about the Oxford Centre for Haematology.