About 15% of patients with hematologic disorders enrolled in a prospective study had a negative antibody response at least 2 weeks after receiving their second COVID-19 vaccination.
Among patients who failed to seroconvert, 72% had lymphoid neoplasms, and patients with indolent or aggressive non-Hodgkin lymphoma (NHL) had the highest rates of negative antibody response. However, seroconversion was observed in 99% of patients with chronic myeloid leukemia (CML).
These results were presented at the 2021 American Society of Hematology (ASH) Annual Meeting by Jil Rotterdam, a medical student at Universität Heidelberg in Mannheim, Germany.
This single-center study included 373 patients with hematologic disorders. The median patient age was 64 years (range, 20-92 years), and 44% were women.
Most patients (n=338) had a hematologic malignancy, including myeloid (n=227) and lymphoid (n=111) neoplasms. Thirty-five patients had a nonmalignant hematologic disease, including autoimmune diseases (n=26) and benign disorders (n=9).
There were 229 patients (61%) receiving active therapy, and 144 patients (39%) who had been treated previously or were treatment naïve.
Patients received 2 doses of the Pfizer-BioNTech vaccine (n=289), Moderna vaccine (n=36), or AstraZeneca vaccine (n=26), or a first dose of the AstraZeneca vaccine with a second dose of the Pfizer-BioNTech vaccine (n=22).
The researchers used an electrochemiluminescence assay (Elecsys, Roche) to quantify antibody levels (pan-immunoglobulin) against the receptor-binding domain of the SARS-CoV-2 spike protein at least 2 weeks after the second COVID-19 vaccination.
The median time from vaccination to analysis was 12 weeks. The vaccination-related antibody response was positive (≥0.8 U/mL) in 85% of patients (317/373), with a mean value of 197 U/mL.
The vaccination-related antibody response was negative (<0.8 U/mL) in 15% of patients (56/373). Among patients with a negative response, 72% (n=40) had lymphoid neoplasms, 21% (n=12) had myeloid neoplasms, and 7% (n=4) had an autoimmune disease.
Most patients with a negative response were receiving active therapy (71%, n=39). Therapies associated with negative results included Bruton tyrosine kinase inhibitors, immunoglobulins, and rituximab. Tyrosine kinase inhibitors were associated with positive results.
The proportion of patients with a negative antibody response, by disease type, was:
- 42% in indolent NHL (25/60)
- 44% in aggressive NHL (8/18)
- 24% in myelodysplastic syndromes (5/21)
- 13% in multiple myeloma (4/31)
- 11% in Hodgkin lymphoma (1/9)
- 5% in acute leukemia (1/20)
- 8% in myeloproliferative neoplasms (6/76)
- 1% in CML (1/101).
“Some patients with hematological diseases do not have adequate antibody response and might therefore not have sufficient protection from vaccination,” Ms Rotterdam said. “[W]e should recommend ongoing protective measures, such as masks, social distancing, and screenings, as well as prioritizing vaccination for family members and caregivers to protect the patients.”
Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
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Rotterdam J, Thiaucourt M, Schwaab J, et al. Antibody response to vaccination with BNT162b2, mRNA-1273, and ChADOx1 in patients with myeloid and lymphoid neoplasms. Presented at ASH 2021; December 11-14, 2021. Abstract 218.