No Increased Risk of irAEs Seen After COVID-19 Vaccination in Patients on ICIs

In a small study, patients with lung cancer who underwent COVID-19 vaccination while receiving immune checkpoint inhibitors (ICIs) did not have an increased risk of immune-related adverse events (irAEs).

However, these patients did have worse antibody responses to COVID-19 vaccination when compared with healthy control individuals. These results were published in the Journal of Thoracic Oncology.

The study included 126 patients with lung cancer who were 20 years of age or older. They were treated with ICIs between 4 weeks before their first COVID-19 vaccination and 4 weeks after their second vaccination. 

The patients’ median age at baseline was 71 years, and 73.0% were men. Nearly all patients (124/126) were vaccinated twice with the Pfizer-BioNTech COVID-19 vaccine (30 μg each) at a median of 21 days apart. The remaining 2 patients were vaccinated twice with the Moderna COVID-19 vaccine (100 μg each) at a median interval of 32 days. 

The most frequently administered ICI was pembrolizumab (49.2%), followed by atezolizumab (22.2%), and durvalumab (16.7%). 

The median observation time from the start of ICI treatment to the first vaccine dose was 208.0 days. The median follow-up was 145.0 days after the first vaccine dose. 

The incidence of irAEs of any grade was 20.6% before COVID-19 vaccination and 5.6% after vaccination. None of the 26 patients with irAEs before vaccination experienced exacerbation of these AEs or developed a new irAE after vaccination. 

The researchers noted that the incidence of irAEs post-vaccination is not higher than the incidence expected without vaccination, which is 35% based on the literature.

The researchers also assessed levels of anti-spike (S) IgG antibodies against SARS-CoV-2 in 65 ICI-treated lung cancer patients and 65 age- and sex-matched healthy control individuals. Both groups were vaccinated twice with the Pfizer-BioNTech COVID-19 vaccine.

In both groups, S-IgG antibody titers peaked at a median of 35 days after the first COVID-19 vaccination. This corresponds to a median of 14 days after the second vaccination. 

On day 35, 96.7% of patients in the lung cancer group and 100% of the healthy control individuals tested positive for S-IgG antibodies (P =.23). However, the median level of S-IgG antibodies was significantly lower in the lung cancer group than in the control group — 3238.6 AU/mL and 12,260.7 AU/mL, respectively (P <.001). 

Based on these findings, the researchers concluded that COVID-19 vaccination may be less effective in patients with lung cancer on active treatment with ICIs. However, vaccination appears safe in this patient group. 

Reference

Hibino M, Uryu K, Takeda T, et al. Safety and immunogenicity of mRNA vaccines against severe acute respiratory syndrome coronavirus 2 in patients with lung cancer receiving immune checkpoint inhibitors: A multicenter observational study in Japan. J Thorac Oncol. Published online June 22, 2022. doi:10.1016/j.jtho.2022.05.015

This article originally appeared on Cancer Therapy Advisor