Over half of multiple myeloma patients develop an antibody response to the COVID vaccine, according to a new study published in The Lancet Haematology. In the study led by Sarah Bird and colleagues at The Institute of Cancer Research in London, Dr. Bird noted that IgG responses were found in 56% of myeloma patients after their first shot, "which rises to 70% when measuring Total antibody." 

While this response percentage is lower than responses seen in the general population, it is still encouraging that the vaccine, even after the first shot, can provide some protection to immunocompromised multiple myeloma patients.

The researchers assessed blood antibodies of 93 myeloma patients following their first dose of the COVID-19 vaccine. The patients had received either the Pfizer (n = 48) or AstraZeneca (n = 45) vaccines. In the study, 52% of the patients had a complete or very good partial response to their myeloma therapy at the time of vaccination. The others in the study included 17% of patients who had a partial response and 29% who had stable or progressive diseases. There was no difference in the percentage of patients who received either the Pfizer or AstraZanenca vaccines. Lower than normal levels of immunoglobulins (called immunoparesis) was identified in 46% of patients. 

From the 93 patients, 56% of them tested positive for SARS-CoV-2 IgG antibodies at a median of 33 days after vaccination. 

Additional findings included the following: 

• Myeloma patients with normal immunoglobulin levels had higher levels of COVID antibodies
• Myeloma patients on any myeloma therapy at the time of vaccination had lower COVID antibody levels (46%) than those off therapy (74%)
• No specific myeloma treatment was related to lower COVID antibody rates
• Antibody rates differed by type of response to myeloma treatment
  • Complete response or Very Good Partial Response (63%)
  • Partial response (75%)
  • Stable or progressive disease (30%)
• In the 8 patients who had undergone autologous stem cell transplant within 12 months of vaccination, 75% had positive antibodies 

The patients who were COVID antibody negative after vaccination were further tested for anti-COVID IgG, IgM and IgA levels. The Total antibody level gave a positive result in 33% of these patients. As a result, the overall positive antibody result (IgG or Total or both) was observed in 70% of the 93 myeloma patients. 

The authors state: 

“Our data suggest lower positive antibody rates in patients with active multiple myeloma, patients with immunoparesis, and patients on any treatment,” the authors wrote. “The only easily reversible risk factor of these is being on therapy, although we did not identify any specific treatment associated with a lower seropositive rate than others.”

The authors note that patients should avoid vaccination on a day they are receiving myeloma treatment (except immunomodulators like Revlimid). Because 30% of myeloma patients not developing a response to the COVID vaccine is concerning, the authors suggest that tracking the non-responding group will be critical so that these patients are not left vulnerable to COVID-19.