COVID‐19 vaccine effectiveness in patients with hematologic malignancy.

Future studies should consider reporting 30-d and all-cause mortality and long COVID or post-acute sequelae of COVID-19 (PASC) as outcomes for COVID-19 vaccine effectiveness in patients with HM. Keywords: blood cancer; breakthrough infections; leukemia; lymphoma; SARS-CoV-2; vaccine effectiveness EN blood cancer breakthrough infections leukemia lymphoma SARS-CoV-2 vaccine effectiveness 1 2 2 12/23/22 20221201 NES 221201 Patients with hematological malignancy (HM), specifically those with B-cell lymphoid malignancies and receipt of anticancer therapies within 12 months prior to coronovirus disease 2019 (COVID-19), are consistently reported to have worse COVID-19 severity, including higher rates of hospitalization, intensive care unit admission, mechanical ventilation, and death, compared to those with solid malignancy.[[1]] Given our prior knowledge about the impact of immunosuppression on response to non-COVID vaccines, it was unsurprising that patients with HM, especially those on lymphocytotoxic therapies, including anti-CD20 mAbs, were significantly less likely to develop adequate seroconversion after two doses of COVID-19 messenger RNA (mRNA) vaccination compared to those with solid malignancy.[3] Although patients may be independently protected by cellular immunity, the majority of the seronegative patients with HM did not elicit CD8+/CD4+ T cell responses after two doses.[4] How this blunted vaccine response translates to clinical outcomes following breakthrough infections in this vulnerable population is largely underexamined. Compared to noncancer patients, the vaccine effectiveness against symptomatic infections seems lower in patients with HM visiting academic centers (cumulative infection risk: 4.9% vs. 14.9%)[7]; however, epidemiological studies are still needed to understand the effectiveness of mRNA vaccination, especially boosters, against COVID-19 severity in this group. [Extracted from the article]