B-cell chronic lymphocytic leukaemia (CLL) is associated with immunosuppression and patients are at increased clinical risk following SARS-CoV-2 infection. Covid-19 vaccines offer the potential for protection against severe infection but relatively little is known regarding the profile of the antibody response following first or second vaccination. We studied spike-specific antibody responses following first and/or second Covid-19 vaccination in 299 patients with CLL compared with healthy donors. 286 patients underwent extended interval (10–12 week) vaccination. 154 patients received the BNT162b2 mRNA vaccine and 145 patients received ChAdOx1. Blood samples were taken either by venepuncture or as dried blood spots on filter paper. Spike-specific antibody responses were detectable in 34% of patients with CLL after one vaccine (n = 267) compared to 94% in healthy donors with antibody titres 104-fold lower in the patient group. Antibody responses increased to 75% after second vaccine (n = 55), compared to 100% in healthy donors, although titres remained lower. Multivariate analysis showed that current treatment with BTK inhibitors or IgA deficiency were independently associated with failure to generate an antibody response after the second vaccine. This work supports the need for optimisation of vaccination strategy in patients with CLL including the potential utility of booster vaccines.

B 细胞慢性淋巴细胞白血病 (CLL) 与免疫抑制有关，感染 SARS-CoV-2 后患者的临床风险增加。Covid-19 疫苗具有预防严重感染的潜力，但对于第一次或第二次疫苗接种后抗体反应的情况知之甚少。我们研究了 299 名 CLL 患者与健康捐赠者在第一次和/或第二次 Covid-19 疫苗接种后的尖峰特异性抗体反应。286 名患者接受了延长间隔（10-12 周）疫苗接种。154 名患者接受了 BNT162b2 mRNA 疫苗，145 名患者接受了 ChAdOx1。通过静脉穿刺或滤纸上干燥的血点采集血样。在接种一种疫苗后，34% 的 CLL 患者（n  = 267）可检测到尖峰特异性抗体反应，而健康捐赠者的这一比例为 94%，患者组中抗体滴度低 104 倍。接种第二次疫苗后，抗体反应增加至 75%（n  = 55），而健康捐赠者的抗体反应为 100%，但滴度仍然较低。多变量分析显示，目前使用 BTK 抑制剂的治疗或 IgA 缺陷与第二次疫苗接种后未能产生抗体反应独立相关。这项工作支持优化 CLL 患者疫苗接种策略的需要，包括加强疫苗的潜在效用。