20th April 2021 // Sarah McDonald
An exciting new study investigating COVID-19 vaccine effectiveness has just been published in Lancet Haematology. The study led by The Institute of Cancer Research, London, and The Royal Marsden NHS Foundation Trust is the first published study testing the effectiveness of COVID-19 vaccines in myeloma patients.
The results from the study show that 70% of myeloma patients had an immune response to the first dose of either the Pfizer-BioNTech or Oxford-AstraZeneca COVID-19 vaccine.
Therefore, these results tell us that most myeloma patients can and do respond well to either vaccine.
The study included 93 myeloma patients who attended the Royal Marsden Hospital, London for their myeloma. The group was mixed and included patients at different stages of treatment. On average, the patients included in the study had received at least one line of treatment and 71% of the group were receiving treatment at the time of vaccination.
The effectiveness of the first dose of the vaccine was assessed by measuring immune response >21 days after vaccination. A positive immune response was determined by the presence of anti-COVID-19 antibodies in the blood.
If like most people you are learning about antibody response for the first time it is important to note that our bodies have billions, if not trillions, of different antibodies. We produce several unique antibodies to fight a specific infection. Therefore, when exposed to COVID-19 or the COVID-19 vaccine our bodies will produce a number of different anti-COVID-19 antibodies. There are five main types or groups of antibody, based on their shape and functionality, they are IgG, IgA, IgM, IgE and IgD. IgG is the most common type of antibody found in the blood; this is why they are commonly used to detect the immune response. The antibodies produced to fight an infection are distinct from the monoclonal antibody (paraprotein) produced by myeloma cells.
The team measured antibody response in two ways – by testing for the presence of a vaccine-specific anti-COVID IgG antibody in the blood and by measuring the total antibody response (the presence of anti-COVID IgG, IgM and/or IgA antibodies in the blood).
The researchers initially measured immune response by testing for the presence of the vaccine-specific anti-COVID-19 IgG antibody in the blood. 56% of the myeloma patients tested positive for the specific anti-COVID IgG antibodies.
Following this, the researchers tested the total antibody response in patients who tested negative for the specific anti-COVID-19 IgG antibody. They found that 33% of these patients had anti-COVID-19 antibodies.
Therefore, overall, the study shows that around 70% of myeloma patients had a positive immune response to the vaccine.
The study measured the immune response to both the COVID-19 vaccines. There was no difference in the antibody response rate between the two vaccines. 54% of patients who received the Pfizer-BioNTech vaccine and 58% of patients who received the Oxford AstraZeneca vaccine had a positive antibody response. This result supports the current guidance for people with myeloma to accept whichever vaccine is offered to them.
The researchers also looked to see if there were any particular patient characteristics (e.g., age, sex, treatment) associated with vaccine response rates.
The findings showed a patient’s age, sex, have no impact on vaccine response. However, myeloma status and immune function might.
Patients with active myeloma, compromised immune function or on any treatment were less likely to have a positive antibody response. The strongest association with poor response was having poorly controlled, non-responsive myeloma. This suggests that the biggest concern regarding vaccine effectiveness is in patients with active and non-responsive myeloma. The patients who are most likely to be severely immunocompromised.
This doesn’t necessarily mean that immunocompromised patients don’t get any protection from the vaccines.
The study only looked at the immune response to the first dose of the vaccine. Therefore, it can’t tell us if the second dose of the vaccine boosts the effectiveness and improves the positive antibody response rate in myeloma patients. There are a number of ongoing studies collecting this data so hopefully, we will know more about the second dose soon. Maybe the immune response in myeloma patients will be even higher.
The study also can’t tell us for certain how well the vaccines protect myeloma patients against COVID-19. Although a positive antibody response is associated with protection it isn’t definitive. The only way to confirm how well the vaccines protect myeloma patients from COVID-19 is to do more research, with more patients, that measures the number of COVID-19 cases following vaccination. Only then will we know if the vaccine reduces the risk of infection or the risk of severe infection.
This is why Myeloma UK have joined the Blood Cancer UK Vaccine Research Collaborative to fund further research into how likely people are to get protection from the vaccine depending on their type of blood cancer and stage of treatment, as well as funding any gaps in the current research to fill any missing pieces.
Nevertheless, this study is good news for myeloma patients, and it starts to paint a better, positive picture of COVID-19 vaccine effectiveness in myeloma. It clearly shows that the majority of myeloma patients respond to the vaccine so hopefully, it provides some reassurance for those worried about vaccine effectiveness.
For me, it confirms that the COVID-19 vaccines play an important role in minimizing the risk of COVID-19 infection and that myeloma patients should get both doses of a COVID-19 vaccine when offered.