Vaccine Info

Janssen Ad26.Mos4.HIV Vaccine

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Last reviewed
January 16, 2024
Fact checked by
Robert Carlson, MD

Janssen Ad26.Mos4.HIV Vaccine - Discontinued

The Janssen Pharmaceutical Companies of Johnson & Johnson, together with a consortium of global partners, announced on January 18, 2023, the results of an independent, scheduled data review of the Phase 3 Mosaico study (also known as HPX3002/HVTN706) of Janssen’s investigational HIV vaccine regimen. The study’s independent Data and Safety Monitoring Board (DSMB) determined that the regimen was not effective in preventing HIV infection compared to placebo among study participants. No safety issues with the vaccine regimen were identified. In light of the DSMB’s determination, the Mosaico clinical trial will be discontinued.

Ad26.Mos4.HIV was a tetravalent vaccine candidate that contains a “mosaic” of HIV genes from different subtypes of the virus that researchers stitched into a harmless adenovirus. The subtypes include Ad26.Mos1.Gag-Pol, Ad26.Mos2.Gag-Pol, Ad26.Mos1.Env, and Ad26.Mos2S. Janssen’s mosaic-based vaccine candidate contains mosaic immunogens (molecules capable of inducing an immune response) that have been created using genes from a wide variety of HIV-1 subtypes to deliver a global vaccine that could be deployed anywhere in the world.

Ad26.Mos4.HIV was based on “mosaic” immunogens—vaccine components featuring elements of multiple HIV subtypes—to induce immune responses against various global HI  strains. The investigational vaccine regimen consisted of four injections over a year of Ad26 Mos4.HIV. This vaccine candidate uses a common-cold virus (adenovirus serotype 26 or Ad26) to deliver the mosaic im unogens. The final two vaccinations were accompanied by a bivalent (two-component) HIV envelope protein formulation, combining clade C gp140 and mosaic gp140 envelope proteins, adjuvanted by aluminum phosphate to boost immune response. All study vaccinations were completed in October 2022. In earlier clinical tests, this vaccine did not trigger neutralizing antibodies but produced high levels of binding antibodies and other immune responses. A booster shot consists of a mosaic version of HIV’s surface protein mixed with an alum adjuvant.

The primary analysis of the Phase 2b Imbokodo study, announced in August 2021, found that a similar investigational HIV vaccine regimen did not provide sufficient protection against HIV in a population of young women in sub-Saharan Africa. 

Learn more at http://www.jan Johnson & Johnson (J&J).

Ad26.Mos4.HIV Vaccine Indication

Ad26.Mos4.HIV is being developed as an anti-HIV vaccine.

Ad26.Mos4.HIV Vaccine Dosage

This vaccine candidate is administered via an intramuscular injection into the left deltoid. Janssen’s investigational preventive HIV vaccine regimen involves four vaccination visits over one year.

Ad26.Mos4.HIV Vaccine News

January 18, 2023 - “We are disappointed with this outcome and stand in solidarity with the people and communities vulnerable to and affected by HIV,” said Penny Heaton, M.D., Global Therapeutic Area Head, Vaccines, Janssen Research & Development, LLC.

July 23, 2019 - Johnson & Johnson Announces New Clinical Data on Mosaic-based HIV Preventive Vaccine Regimen. The study, ASCENT (HPX2003/HVTN 118), found that adding a bivalent soluble protein to the regimen (a combination of Clade C and Mosaic gp140) improved the breadth of immune responses to different HIV strains circulating worldwide. 

Ad26.Mos4.HIV Vaccine Clinical Trials 

Mosaico, a Phase 3 study of Janssen’s investigational HIV vaccine regimen, began in 2019 and completed vaccinations in October 2022. The study included approximately 3,900 cisgender men and transgender people who have sex with cisgender men and/or transgender people, who represent groups and populations vulnerable to HIV, at over 50 trial sites in Argentina, Brazil, Italy, Mexico, Peru, Poland, Puerto Rico, Spain, and the United States. The study evaluated an investigational vaccine regimen containing a mosaic-based adenovirus serotype 26 vector (Ad26.Mos4.HIV) administered during four vaccination visits over one year. A mix of soluble proteins (Clade C/Mosaic gp140, adjuvanted with aluminum phosphate) was also administered at visits three and four.

The Mosaico DSMB analysis, based on the data available to date, indicated that the regimen does not protect against HIV, and the study is not expected to meet its primary point. No safety issues with the vaccine regimen were identified. In light of this, the study will be discontinued, and further analyses are underway. The DSMB’s determination follows the primary analysis of the Phase 2b Imbokodo study, announced in August 2021, and found that a similar investigational HIV vaccine regimen did not provide sufficient protection against HIV in a population of young women in sub-Sahara  Africa. The investigational vaccine regimen used in the Imbokodo study was found to have a favorable safety profile.

The Mosaico study was led by a global public-private partnership including the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), the HIV Vaccine Trials Network (HVTN), the U.S. Army Medical Research and Development Command (USAMRDC), and Janssen Vaccines & Prevention B.V. Since 2005, Janssen Vaccines & Prevention B.V. has been participating as a sub-grantee in the NIH-supported Integrated Preclinical/Clinical AIDS Vaccine Development (IPCAVD) program under grants AI066305, AI078526, AI096040 and AI128751 (Principal Investigator, Prof. Dan Barouch).

Clinical Trial NCT04983030: Safety, Immunogenicity, Efficacy of Ad26.Mos4.HIV, MVA-BN-HIV and PGT121, PGDM1400, and VRC07-523LS in HIV-1-Infected Adults. This multi-center study has not begun re-uniting.  Thirty-six participants ages 19-70 will be recruited for this randomized, parallel-group, placebo-controlled, double-blind, Phase 1/2a clinical study.

Clinical Trial NCT03060629:  A Study to Assess the Efficacy of a Heterologous Prime/Boost Vaccine Regimen of Ad26.Mos4.HIV and Aluminum Phosphate-Adjuvanted Clade C gp140 in Preventing Human Immunodeficiency Virus (HIV) -1 infection in Women in Sub-Saharan Africa.

Clinical Trial NCT03964415:  A Study of Heterologous Vaccine Regimen of Adenovirus Serotype 26 Mosaic4 Human Immunodeficiency Virus(Ad26.Mos4.HIV), Adjuvanted Clade C gp140 and Mosaic gp140 to Prevent HIV-1 Infection Among Cis-gender Men and Transgender Individuals Who Have Sex With Cis-gender Men and/or Transgender Individuals (MOSAICO

Clinical Trials

No clinical trials found