Protecting vulnerable patients with haematological malignancies from COVID-19 has moved relatively quickly from prevention through social distancing then vaccination to include other risk management strategies and treatment with antivirals and monoclonal antibodies.
The HSANZ, in collaboration with major stakeholders, has recently developed a comprehensive binational consensus position statement on the use of COVID-19 therapeutics in patients with haematological malignancies.
It acknowledges the ongoing high rate of transmission of SARS-CoV2 in the community and the “unacceptably high” risk for immunocompromised patients with haematological malignancies.
It also notes the environment continues to change rapidly including with emerging SARS-CoV-2 variants and that advice will inevitably change in response.
Some of their recommendations included:
The statement includes advice for managing patients with suboptimal vaccine response based on disease or treatment and the role of tixagevimab and cilgavimab as pre-exposure prophylaxis.
It says patients on BTKi, BCL2 inhibitors and JaK2 inhibitors and patients who have received anti CD20 therapy in the last 12 months are the least likely to respond to COVID vaccination and therefore should be considered for prophylaxis.
“Tixagevimab/cilgavimab can also be considered before initiation of therapy based on vaccination history, disease risk, B-cell depleting potential of the underlying treatment, and the likelihood of response to future vaccination,” the statement said.
The statement noted that in mild to moderate COVID-19, anti-SARS-CoV-2 monoclonal antibodies such as sotrovimab were effective at reducing ED presentations, ICU admissions and all cause death but only when administered within five days of symptoms onset.
“Of note, the activity of this agent depends on the underlying variant of SARS-CoV-2, and it is unlikely that sotrovimab is effective against the B.1.1.529/BA.2 strains,” it said.
Antivirals such as Paxlovid were also effective if administered early but there was the possibility of multiple drug interactions.
“The ritonavir component is a strong CYP3A inhibitor, and can increase concentration and toxicity risk of many cancer therapies including BTK inhibitors, venetoclax, brentuximab, vincristine, ruxolitinib and prednisone.”
The statement highlighted that patients with haematological malignancies and moderate to severe COVID-19 required multidisciplinary care including input from intensive care, infectious diseases, and respiratory medicine.
The statement said immunocompromised individuals can have prolonged COVID-19 infection and viral shedding which in part may relate to the development of T-cell exhaustion.
“Consequently, this can cause difficulty in de-isolating patients following infection, as well as delayed manifestations of COVID-19.”
It said the guidance regarding surveillance testing and re-treatment was mixed.
“Increasingly, use of PCR cycle threshold (Ct) and viral cultures may be used to guide management and de-isolation of patients with persistent PCR positivity.”
It said that local models for screening, assessment and management of long COVID were emerging.
Key stakeholders in the development of the position statement included the Australasian Society of Infectious Diseases, Leukaemia Foundation, Lymphoma Australia, Myeloma Australia, and Leukaemia & Blood Cancer New Zealand.
Australia and New Zealand Transplant and Cellular Therapies (ANZTCT) has separate position statements – here and here – on vaccination and treatment of patients planned for or who have received haematopoietic stem cell transplant or CAR T-therapies.