N.M. first and second dose of BNT162b2 and mRNA-1273 SARS-CoV-2 vaccines in patients with cancer in US and Europe from January to April 2021. Among 131 patients, most (94%) achieved seroconversion after receipt of two vaccine doses. Seroconversion rates and antibody titers in patients with hematological malignancy were significantly lower than those with solid tumors. None of the patients with history of anti-CD-20 antibody in the 6?months before vaccination developed antibody response. Antibody titers were highest for clinical surveillance or endocrine therapy groups and lowest for cytotoxic chemotherapy or monoclonal antibody groups. Keywords: COVID-19, vaccine, immune response, malignancy, tumor, pandemic, seroconversion, antibody, oncology, anti-cancer treatment Graphical abstract Open in a separate window Addeo et?al. show patients with cancer have poor antibody Linaclotide response after one dose and excellent antibody response at 3?weeks after two doses with mRNA COVID-19 vaccines. A subset of immunocompromised patients (i.e., those receiving anti-CD20), are at high risk for not developing antibodies post-vaccination. Introduction The novel coronavirus disease 2019 (COVID-19) pandemic has spread throughout the world with over 161 million confirmed cases globally and more than 3 million deaths as of May 2021 (https://covid19.who.int/). Unprecedented global effort has been made to develop different SARS-CoV-2 vaccines using technologies based on messenger RNA (mRNA), synthetic long viral peptides, plasmid DNA, and inactivated, attenuated, or genetically modified viruses, including BNT162b2 (Pfizer-BioNTech)?(Polack et?al., 2020), mRNA-1273 (Moderna) (Baden et?al., 2020), AZD1222 (Oxford/AstraZeneca) (Voysey et?al., 2021), Ad26.COV2.S (Johnson & Jonhson) (Sadoff et?al., 2021), Sputnik V (Gamaleya) (Logunov et?al., 2021), and BBIBP-CorV (Sinopharm) (Xia et?al., 2021)). Efficacy ranges between 60% and 94% with excellent safety profile in the general population. However, scarce experimental data about safety and efficacy of vaccine have been reported on patients with cancer, as those on active therapy were excluded from SARS-CoV-2 vaccine clinical trials (Friese et?al., 2021). Compared with the general population, patients with cancer are more likely to be at high risk of serious COVID-19-related complications and mortality (Bakouny et?al., 2020; Grivas et?al., 2021; Kuderer et?al., 2020), hence having information about efficacy of vaccine and optimal timing in relation to anti-cancer therapy to promote an effective immunity in this population remains crucial. Here, we report results from an international collaborative prospective cohort study assessing short-term humoral immune?response (seroconversion rates and antibody titers) by measuring anti-SARS-CoV-2 spike protein (S) immunoglobulin G (IgG) antibody titer as a surrogate after two doses of mRNA vaccines (mRNA-1273 and BNT162b2) in two different cohorts of patients with solid and hematological malignancies. To put our study findings in the context of the existing literature, we also present data from Linaclotide available studies (published or pre-print) examining anti-S IgG antibody response rates in patients with cancer who received SARS-CoV-2 vaccines. Results Study cohort We enrolled a total of 140 patients with cancer who received Linaclotide either BNT162b2 or mRNA-1273 vaccine at one of the enrolling sites. Among these patients, 131 were SARS-CoV-2 naive as determined by a negative anti-SARS-CoV-2 nucleocapsid (N) protein IgG test at baseline, and thus included in the immunogenicity analysis. Study cohort characteristics are listed in Table 1 . The median follow-up time was 50 (interquartile range [IQR]: 49C55) days, which is equivalent to 22 (22C24) days after receipt of a second vaccine dose. The median Rabbit Polyclonal to PMS2 (IQR) age at vaccination was 63 (55C69) years and the racial/ethnic distribution of patients was: non-Hispanic white (80%), Hispanic (18%), and black (2%). There was an almost equal proportion of males (55%) and females (45%) at both sites. Most malignancies were solid tumors (81%), with breast (33%) and urological (19%) cancer being the most common solid tumor types. Twenty-five (19%) patients had hematological malignancy. Approximately, one-third did not receive anti-cancer therapy within 6?months before COVD-19 vaccination. The most common anti-cancer therapy received by this cohort of patients was cytotoxic chemotherapy (23%), followed by endocrine therapy (15%), monoclonal antibody therapy (13%), kinase inhibitor therapy (11%), and immunotherapy (11%). Table 1 Clinical characteristics of the study cohort.

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