Johnson & Johnson COVID-19 Booster, Administered Six Months After Two-Dose Regimen of BNT162b2, Shows Substantial Increase in Antibody and T-cell Responses

Preliminary Phase 2 study and a sub-study demonstrate value of mix-and-match approach; Johnson & Johnson booster increased neutralizing and binding antibodies, similar to boosting with BNT162b2, and showed strong increase in T-cell responses

NEW BRUNSWICK, N.J., DECEMBER 5, 2021 – Johnson & Johnson (NYSE: JNJ) (the Company) today announced preliminary results from an independent study, including a subset of participants from the Janssen-sponsored COV2008 study, conducted by Dan Barouch, M.D., Ph.D., et al. of Beth Israel Deaconess Medical Center (BIDMC), which showed that a booster shot of the Johnson & Johnson COVID-19 vaccine (Ad26.COV2.S), administered at six months after a two-dose primary regimen of BNT162b2, increased both antibody and T-cell responses. These results demonstrate the potential benefits of heterologous boosting (mix-and-match). The article describing these results have been posted on medRxiv.

“There is early evidence to suggest that a mix-and-match boosting approach may provide individuals with different immune responses against COVID-19 than a homologous boosting approach,” said Dan Barouch, M.D., Ph.D., Director of the Center for Virology and Vaccine Research at BIDMC. “In this preliminary study, when a booster dose of Ad26.COV2.S was given to individuals six months after a primary regimen with the BNT162b2 vaccine, there was a comparable increase of antibody responses at week four following the boost and a greater increase of CD8+ T-cell responses with Ad26.COV2.S compared with BNT162b2.”

“These results provide valuable scientific insights for our vaccine when used as a mix-and-match booster and can help inform boosting strategies with the goal to curb the pandemic,” said Mathai Mammen, M.D., Ph.D., Global Head, Janssen Research & Development, Johnson & Johnson. “These data add to the growing body of evidence demonstrating that a mix-and-match booster dose of the Johnson & Johnson COVID-19 vaccine successfully increases humoral responses and cellular responses against the original strain of SARS-CoV-2, as well as the Beta and Delta variants.”

These Phase 2 data are reinforced by preliminary results from the UK COV-BOOST clinical study published in The Lancet, which demonstrated that following primary vaccination with two doses of either BNT162b2 (n=106) or ChAdOx1 nCov-19 (n=108), a booster dose of the Johnson & Johnson COVID-19 vaccine increased both antibody and T-cell responses.

Cellular (T-Cell) Responses
In this preliminary study, boosting with the Johnson & Johnson COVID-19 vaccine after a primary vaccine regimen of BNT162b2 appears to lead to a greater increase in CD8+ T-cell responses than boosting with BNT162b2. These T-cell response data suggest differences between immune responses following homologous boosting with BNT162b2, and mix-and-match boosting with the Johnson & Johnson COVID-19 vaccine following a primary regimen of BNT162b2.

The Johnson & Johnson COVID-19 vaccine leverages Janssen’s AdVac^® technology and cell-mediated immunity, including CD4+ and CD8+ responses. T-cells can target and destroy cells infected by the virus that causes COVID-19. Specifically, CD8+ T-cells can directly destroy infected cells and are aided by CD4+ T-cells.

Humoral (Antibody) Responses
Both the Johnson & Johnson COVID-19 vaccine and BNT162b2 as boosters led to similar neutralizing and binding antibody levels against the original SARS-CoV-2 strain, as well as the Delta and Beta variants, four weeks following the boost. However, after a mix-and-match booster dose of the Johnson & Johnson COVID-19 vaccine, antibodies continued to increase for at least four weeks whereas in individuals who received a homologous boost with the BNT162b2 vaccine, antibodies declined from week two to week four post-boost.

Neutralizing antibodies are capable of binding to the virus in a way that blocks infection and confines the virus to the upper respiratory tract. Binding antibodies can bind to the virus’ spike protein and inactivate the virus through non-neutralizing antiviral functionalities.

Study Design
For this study, a specimen biorepository at Beth Israel Deaconess Medical Center (BIDMC) obtained samples from individuals who received the BNT162b2 vaccine. Participants either continued follow-up in the biorepository and were boosted with 30 ug BNT162b2 (n=24) or were enrolled in the COV2008 study (NCT04999111) and were boosted with 5, 2.5, or 1x10¹⁰ vp of the Johnson & Johnson COVID-19 vaccine (n=41). The COV2008 study is a Johnson & Johnson sponsored, ongoing, blinded Phase 2 clinical trial (VAC31518COV2008) to evaluate its COVID-19 vaccine as a booster in adults 18 years of age and older.

The U.S. Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) has recommended the Johnson & Johnson COVID-19 vaccine as a booster for all eligible individuals aged 18 years and older who receive an authorized COVID-19 vaccine.

Johnson & Johnson continues to submit relevant data to other regulators, the World Health Organization (WHO) and National Immunization Technical Advisory Groups (NITAGs) worldwide to inform decision-making on local vaccine administration strategies, as needed.

In collaboration with academic groups in South Africa and around the world, the Company has been evaluating the effectiveness of its COVID-19 vaccine across variants, now including the new and rapidly spreading Omicron variant. In addition, the Company is pursuing an Omicron-specific variant vaccine and will progress it as needed.

For more information on the Company’s multi-pronged approach to helping combat the pandemic, visit: www.jnj.com/covid-19.