In an Israeli single-institution study reported in The Lancet Oncology, Ligumsky et al found that a booster dose of the SARS–CoV-2 Pfizer-BioNTech BNT162b2 mRNA vaccine given in August or September 2021 was immunogenic in patients receiving active cancer treatment. Antibody levels prior to and after the booster dose were lower in patients with cancer vs matched healthy subjects.
The study involved 72 patients with solid tumors receiving active treatment at Tel Aviv Sourasky Medical Center and 144 healthy health-care workers at the center matched for sex and age. Active treatment was defined as any intravenous anticancer medication given up to 3 weeks before or up to 3 weeks after booster administration.
All participants had received two doses of the BNT162b2 mRNA vaccine, and none had a documented history of SARS–CoV-2 infection. Booster doses were administered between August 1 and September 29, 2021, with immunogenicity assessed at 1 month.
Patients had a median age of 62 years, and 65% of both groups were women. Overall, 75% of patients had metastatic disease.
For the patient vs control groups, median times between the second and booster dose were 210 vs 217 days, and median times between second dose and prebooster antibody testing were 203 vs 210 days.
Our data suggest a high rate of waning immunogenicity in patients with cancer approximately 6 months after the administration of the second dose of BNT162b2 and support the use of a booster dose in this vulnerable population of actively treated patients with cancer.— Ligumsky et al
The median time from booster to postbooster antibody testing was 33 days (interquartile range [IQR] = 21–44 days) in patients with cancer vs 27 days (IQR = 23–29 days) in the control group (P = .0056). Prior to booster administration, 28% of patients with cancer vs 1% of the control group were found to be seronegative (P < .0001). After booster administration, 3 patients vs 0 control were seronegative.
Median IgG antibody titers increased significantly after the booster in the patient group, from 24.64 to 1,887.32 binding antibody units (BAU)/mL (P < .0001) and in the control group, from 159.6 to 3,270 BAU/mL (P < .001). Both prebooster and postbooster titers were significantly higher in the control group (both P = .00011). On multivariate analysis including study group and time before or after third dose and adjusted for age and sex, booster administration was the only significant factor associated with titer increase (P < .0001).
The most common adverse events in patients with cancer were pain at the injection site (49%), fatigue (28%), and fever (13%). Patients with cancer had a lower incidence of headache (P = .0046), muscle pain (P < .0001), and chills (P = .026) vs controls. No adverse events were life-threatening or required hospitalization or any other intervention.
The investigators concluded, “Our data suggest a high rate of waning immunogenicity in patients with cancer approximately 6 months after the administration of the second dose of BNT162b2 and support the use of a booster dose in this vulnerable population of actively treated patients with cancer.”
Hagai Ligumsky, MD, PhD, of the Tel Aviv Sourasky Medical Center, Tel Aviv University, is the corresponding author for The Lancet Oncology article.