Interim results from a Phase 1/2a sub-study published in the New England Journal of Medicine(NEJM) demonstrated that both humoral (antibody) and cellular (T-cell) immune responses generated by the Johnson & Johnson single-shot COVID-19 vaccine were strong and stable through eight months after immunization, the length of time evaluated to date. Data showed that T-cell responses - including the important CD8+ T-cells that seek out and destroy infected cells - persisted over the eight-month timeframe examined. The Company announced topline preprint study results from this Phase 1/2a sub-study on July 1, 2021.

Data from the study conducted in collaboration with Dan Barouch, M.D., Ph.D., et al. of Beth Israel Deaconess Medical Center suggest maturation of B-cell response without further boosting. Mature B-cells produce antibodies, which can help fight the virus that causes COVID-19.

Findings indicate that a single dose of the Johnson & Johnson COVID-19 vaccine elicited dual mechanisms of protection against COVID-19 disease, including against disease caused by the Delta variant (B.1.617.2) and other SARS-CoV-2 variants of concern, including the Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Epsilon (B.1.429) and Kappa (B.1.617.1) variants, as well as the original SARS-CoV-2 strain (WA1/2020). These data suggest an expansion of neutralizing antibodies over eight months, along with the observations of durable T-cell responses and the suggestion of B-cell maturation.

"These peer-reviewed data provide further and deeper insights into the durable humoral and cellular immune responses elicited by the single-shot Johnson & Johnson COVID-19 vaccine, thus offering potentially a dual mechanism of protection against COVID-19 disease, including against the Delta variant and other variants of concern," said Mathai Mammen, M.D., Ph.D., Global Head, Janssen Research & Development, Johnson & Johnson. "The study showed that variant specific neutralizing antibodies increased over the eight months examined after vaccination which suggests the maturation of B-cell responses. In addition, the T-cell responses are especially strong and stable over time, which is also potentially important for activity against these variants."

Sum total of recent data affirm ability to generate multiple components of immune responses

These data also extend and complement previously published results in Nature, which provided evidence of the vaccine's ability to elicit multiple components of the immune system in individuals, as well as preclinical data in Nature related to efficacy against SARS-CoV-2 infection due to the Beta variant in non-human primates. Collectively, these analyses indicate that the potential efficacy of vaccines against COVID-19, including disease caused by variants, should be considered in a broader immunological context regarding the role of non-neutralizing antibodies, B- and T-cells.

Additional data from a new analysis of blood samples obtained from a subset of participants (n=8) in the Phase 3 ENSEMBLE study posted on bioRxiv showed that the Johnson & Johnson single-shot COVID-19 vaccine elicited neutralizing antibody activity against the Delta variant at a higher level than what was recently observed for the Beta variant in South Africa.

Phase 1/2a Study Design (VAC31518COV1001)

This ongoing Phase 1/2a multi-center, randomized, double-blind, placebo-controlled trial aims to evaluate the safety, reactogenicity and immunogenicity of the Janssen COVID-19 Vaccine at two dose levels (5x1010 or 1x1011 virus particles), administered intramuscularly as single-dose or two-dose schedules, eight weeks apart, in healthy adults. The study is ongoing at multiple clinical sites in Belgium and the United States.

The results from this sub-study are from cohort 1b of this ongoing Phase 1/2a study, which enrolled 25 adults who are 18-55 years of age at a single site at Beth Israel Deaconess Medical Center for detailed descriptive exploratory immunogenicity studies. Additional follow-up with trial participants is currently underway.

Johnson & Johnson's COVID-19 Vaccine 

The Johnson & Johnson COVID-19 vaccine leverages the AdVac? vaccine platform proprietary technology that was also used to develop and manufacture Janssen's European Commission-approved Ebola vaccine regimen and construct its investigational Zika, RSV and HIV vaccines.

This Phase 1/2a clinical trial has been funded in part with federal funds from the U.S. Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response, Biomedical Advanced Research and Development Authority (BARDA), under other transaction authority ("OTA") agreement No. HHSO100201700018C.