To inform healthcare policy for immunosuppressed patients there is a need to define SARS-CoV-2 vaccine responses. Here we report SARS-CoV-2 vaccine-induced antibody and T cell responses in patients treated with anti-tumour necrosis factor (anti-TNF), a commonly used biologic in inflammatory diseases, compared to patients treated with vedolizumab, a gut-specific antibody targeting integrin a4b7 that does not impair systemic immunity. In anti-TNF recipients, the magnitude of anti-SARS-CoV2 antibodies was reduced five-fold, and rapidly decayed towards the seroconversion threshold by 14 weeks after second dose of vaccine. In contrast, anti-SARS-CoV-2 antibodies were sustained up to 16 weeks in vedolizumab-treated patients. Anti-SARS-CoV2 antibody decay was not observed in vaccinated patients previously infected with SARS-CoV-2. T cell responses were absent in one-fifth of anti-TNF and vedolizumab-treated patients after a second dose of either vaccine. Our data have important implications for anti-TNF recipients, including the need for vaccine prioritization, booster doses, and social distancing strategies.