Short summary

This study aim to determine when patients with cancer should recieve COVID-19 vaccination to obtain an efficient immune response.

Rationale

Cancer patients as a group are of higher risk of severe disease following infection with SARS-CoV-2. This is particularly the case for cancer patients with hematological and lung malignancies as well as those with metastatic disease.

Although evidence regarding vaccination in cancer patients is limited, there is sufficient evidence to support anti-infective vaccination in general, but excluding live-attenuated vaccines and replicationcompetent vector vaccines, even in cancer patients undergoing immunosuppressive therapy. The level of efficacy may be expected to be generally reduced in certain populations of cancer patients with intense immunosuppression, such as recipients of hematopoietic stem cell transplantation.

However, based on data extrapolation from other vaccines and the mechanism of action of the COVID-19 vaccines (not live), it is conceivable that the efficacy and safety of vaccination against COVID-19 may be estimated to be similar to that of patients without cancer, although data from clinical trials are not available. And the benefits of vaccination seem to significantly and substantially outweigh the risks.

The optimal timing of vaccination remains uncertain and likely depends on individual therapy scenarios. It has been proposed that vaccination may ideally occur before systemic therapy starts.

However, if the patient has already started systemic therapy, it is reasonable to vaccinate during therapy. Some immunocompromised cancer patients might not achieve a sufficient immune response to vaccination.

Thus, there is a need for determining when the optimal time is for patient with cancer to receive vaccination to obtain an efficient immune response.

Description of the cohort

A prospective study of 1000 cancer patients at the Department of Oncology or Department of Hematology, Odense University Hospital.

All adult (> 18 years) patients diagnosed with a solid tumor or hematological disease with one of following:

a) in systemic treatment (chemotherapy, immunotherapy etc. )

b) in radiotherapy, or

c) follow-up

Data and biological material

Blood sampling will be performed:

• prior to COVID-19 vaccination

• immediately after and up to six weeks after the second COVID-19 vaccination

• After approximately 6 months, 1 year and 2 years

Collaborating researchers and departments

Department of Hematology, Odense University Hospital

• Prof. Henrik Frederiksen