Vaccine Info

Ad26.COV2-S Vaccine

Last Reviewed
November 19, 2020

Ad26.COV2-S (JNJ-78436735) Vaccine Description

Johnson and Johnson (J&J) and Janssen Pharmaceutical research teams, in collaboration with Beth Israel Deaconess Medical Center, part of Harvard Medical School, constructed and tested multiple vaccine candidates using the Janssen AdVac® technology, and have selected its lead vaccine candidate Ad26.COV2-S (Ad26COVS1) (JNJ-78436735) recombinant for the prevention of coronavirus infection.

The JNJ-78436735 vaccine candidate leverages Janssen's AdVac and PER.C6® technologies. These are the same technologies Janssen used to develop and manufacture the Company's Ebola vaccine, Ad26.ZEBOV.

J&J stated 'it anticipates the first batches of a COVID-19 vaccine could be available for emergency use authorization in early 2021. As the Company progresses the clinical development of its Ad26.COV2-S vaccine candidate, it continues to increase manufacturing capacity and is in active discussions with global partners to ensure worldwide access.'

J&J and Janssen Vaccines & Prevention B.V. stated it is committed to the goal of supplying more than 1 billion doses globally through the course of 2021, provided the vaccine is safe and effective. For more information on Johnson & Johnson’s JNJ-78436735 approach to combatting the pandemic, Learn more at

Ad26.COV2-S (JNJ-78436735) Vaccine Distribution Agreements

J&J announced the European Commission (EC), acting on behalf of the European Union (EU) Member States, has approved an Advance Purchase Agreement in which the Janssen Pharmaceutical Companies will supply 200 million doses of its COVID-19 vaccine candidate to the EU Member States following approval or authorization from regulators. The EU Member States also have the option to secure up to 200 million additional doses.

Ad26.COV2-S (JNJ-78436735) Vaccine Indication

Janssen's vaccine candidate (JNJ-78436735) will be indicated to prevent infection from SARS-CoV-2 coronavirus, which leads to COVID-19 disease in humans. SARS-CoV-2 belongs to a group of viruses called coronaviruses that attack the respiratory system.

No pediatric vaccine efficacy data has been disclosed.

Ad26.COV2-S (JNJ-78436735) Vaccine Dosage

Ad26COVS1 was evaluated at 2-dose levels in a phase 1 study, administered intramuscularly as a single-dose or 2-dose schedule, with a single booster vaccination administered in one cohort.

The phase 2 study's primary purpose is to assess humoral immune responses of 3 dose levels of Ad26.COV2.S administered intramuscularly (IM) as a 2-dose schedule (56 days apart); Ad26.COV2.S administered IM as a single vaccination, and to test both compressed and expanded 2-dose schedules of Ad26.COV2.S (28 and 84 days apart).

The phase 3 ENSEMBLE study is studying the safety and efficacy of a single vaccine dose.

Ad26.COV2-S (JNJ-78436735) Vaccine News

  • November 14, 2020 - Johnson & Johnson announced the expansion to the partnership between its Janssen Pharmaceutical Companies and the Biomedical Advanced Research and Development Authority (BARDA) for the ongoing development of Janssen's investigational COVID-19 vaccine candidate, Ad26.COV2-S.
  • November 2, 2020 - South Africa-based Aspen Pharmacare Limited announced it has entered into a preliminary agreement with Janssen Pharmaceuticals, Inc. (Johnson & Johnson) for the technical transfer and proposed commercial manufacture of their COVID-19 vaccine candidate, Ad26.COV2-S. Aspen Pharmacare stated 'it will perform formulation, filling and secondary packaging of the vaccine for supply to Johnson & Johnson.
  • October 23, 2020 - Johnson & Johnson announced today that it is preparing to resume recruitment in the pivotal Phase 3 ENSEMBLE trial of its investigational Janssen COVID-19 vaccine in the United States after a temporary pause.
  • October 12, 2020 - J&J announced it temporarily paused further dosing in all our COVID-19 vaccine candidate clinical trials, including the Phase 3 ENSEMBLE trial, due to an unexplained illness in a study participant. Following its guidelines, the participant’s illness is being reviewed and evaluated by the ENSEMBLE independent Data Safety Monitoring Board as well as our internal clinical and safety physicians.
  • October 8, 2020 - Johnson & Johnson announced the European Commission, acting on behalf of the European Union (EU) Member States, has approved an Advance Purchase Agreement in which the Janssen Pharmaceutical Companies will supply 200 million doses of its COVID-19 vaccine candidate to the EU Member States following approval or authorization from regulators.
  • October 4, 2020 - J&J announced interim analysis from the ongoing Phase 1/2a clinical trial of the Janssen COVID-19 vaccine candidate (JNJ-78436735). The data demonstrate that a single dose of JNJ-78436735 induced a strong neutralizing antibody response in nearly all participants aged 18 years and older and was generally well-tolerated. Immune responses were similar across the age groups studied, including older adults.
  • September 26, 2020 - Interim results of a phase 1/2a, double-blind, randomized, placebo-controlled trial - Safety and immunogenicity of the Ad26.COV2.S COVID-19 vaccine candidate.
  • September 25, 2020 - Safety and immunogenicity of the Ad26.COV2.S COVID-19 vaccine candidate: interim results of a phase 1/2a, after only a single dose is supportive for further clinical development of Ad26.COV2.S at a dose level of 5x1010 vp, as a potentially protective vaccine against COVID-19.'
  • September 25, 2020 - Grand River Aseptic Manufacturing (GRAM) announced entering into an agreement with Janssen Pharmaceuticals, Inc. to support the manufacture of its SARS-CoV-2 vaccine candidate. The Johnson & Johnson vaccine candidate being manufactured at GRAM is being developed, in part, with funding from BARDA. BARDA, in collaboration with JPEO-CBRND, also is funding a demonstration of manufacturing capability that is expected to result in 100 million doses of the investigational vaccine which the federal government will own.
  • September 23, 2020 - JNJ announced the launch of its large-scale, pivotal, multi-country Phase 3 trial (ENSEMBLE) for its COVID-19 vaccine candidate, JNJ-78436735, being developed by its Janssen Pharmaceutical Companies.
  • September 13, 2020 - Janssen Vaccines & Prevention B.V. will begin mid-stage trials of its COVID-19 vaccine in Spain. About 190 people would take part in Spain's trials, which will take place in 3 hospitals and be concluded by September 22, 2020. The Spanish study is part of Phase II trials of the vaccine that are being carried out in three countries, also including the Netherlands and Germany. The phase 2 trials will last two months and include 550 participants in total.
  • September 3, 2020 - J&J reported Janssen’s lead SARS-CoV-2 investigational vaccine candidate, Ad26.COV2.S, prevented severe clinical disease in Syrian golden hamsters, upon challenge with SARS-CoV-2, the virus that causes COVID-19 in people. 
  • August 26, 2020 - Johnson & Johnson has added Chile, Argentina, and Peru to the Latin nations where it plans to conduct Phase III trials for its vaccine against COVID-19 disease. The company told Reuters it was waiting for regulatory approval in Chile, Argentina, and Mexico.
  • August 18, 2020 - Brazil's Health regulator Anvisa said it had given the green light a vaccine study that will see 6,000 people in Brazil volunteer to trial the vaccine contender of Johnson & Johnson’s pharmaceutical subsidiary Janssen.
  • August 14, 2020 - Janssen Pharmaceutica NV, one of the Janssen Pharmaceutical Companies of Johnson & Johnson, has agreed in principle to collaborate with the United Kingdom of Great Britain and Northern Ireland on a global Phase 3 clinical trial to explore the 2--dose regimen of Janssen’s SARS-CoV-2 vaccine candidate, Ad26.COV2.S. This global study will run in parallel to the Phase 3 trial investigating the single-dose regimen of Ad26.COV2.S.
  • August 9, 2020 - The Kingdom of Saudi Arabia announced it will soon begin a Phase 3 clinical trial of around 5,000 people for COVID-19 disease preventive vaccine known as Ad5-nCoV.
  • August 5, 2020 - J&J announced that it will develop and deliver 100 million doses of its coronavirus vaccine for the U.S. government in a deal totaling more than $1 billion. This agreement offers the U.S. the option to order an additional 200 million doses.
  • July 30, 2020 - The 4 Latest Facts About Johnson & Johnson’s Investigational COVID-19 Vaccine.
  • July 30, 2020 - A new study showed that Janssen's investigational vaccine elicited an immune response against SARS-CoV-2 in a preclinical, nonhuman study. Based on the positive data from this preclinical study, the first-in-human Phase 1/2a clinical trial is now underway in the USA and Belgium, with a Phase 3 study expected to commence in September 2020.
  • July 17, 2020 - The NYTimes reports clinical trials of the vaccine will begin in Belgium. Dr. Barouch’s team will soon start up a trial in Boston.
  • July 16, 2020 - J&J's Wolk said the Phase 1 trial of Ad26COVS1 is expected to enroll more than 1,000 participants, primarily between the ages of 18 and 55 years old, although the company also plans to include a group of people who are 65 years old or older in the early-stage trial. He also said that J&J is in talks with the National Institutes of Health to move up the timeline for the anticipated Phase 3 trial to late September 2020.
  • July 6, 2020 - Emergent BioSolutions Inc. announced a 5-year manufacturing services agreement with Janssen Pharmaceuticals, Inc., one of the Janssen Pharmaceutical Companies of Johnson & Johnson, for large-scale drug substance manufacturing for the investigational vaccine, Ad26.COV2-S. Emergent will provide contract development and manufacturing (CDMO) services valued at approximately $480 million for the first two years.
  • June 10, 2020 - Johnson & Johnson today that through its Janssen Pharmaceutical Companies (Janssen) it has accelerated the initiation of the Phase 1/2a first-in-human clinical trial of its investigational SARS-CoV-2 vaccine, Ad26.COV2-S, recombinant.
  • May 28, 2020 - A new article published in The Lancet, The starting line for COVID-19 vaccine development, identifies questions are whether responses are sustained over time and whether they correlate with clinical protection after exposure to a circulating strain of SARS-CoV-2. 
  • April 29, 2020 - Janssen Pharmaceutical Companies of Johnson & Johnson announced Catalent’s Biologics business unit will accelerate the availability of manufacturing capacity and prepare for large-scale commercial manufacturing at its facility in Bloomington, Indiana, of Johnson & Johnson’s lead vaccine candidate for COVID-19. The collaboration commits joint investment to accelerate the rapid scale-up of segregated manufacturing capacity over the coming months to support the dedicated production of Johnson & Johnson’s investigational vaccine candidate.
  • April 23, 2020 - Emergent BioSolutions Inc. announced an agreement whereby Emergent will deploy its contract development and manufacturing services to support the manufacturing of Johnson & Johnson’s lead vaccine candidate for COVID-19 that leverages the AdVac® and PER.C6® technologies from the Janssen Pharmaceutical Companies of Johnson & Johnson. Under the agreement, valued at approximately $135 million, Emergent will provide drug substance manufacturing services with its molecule-to-market CDMO offering, supported by investments from Johnson & Johnson beginning in 2020, and will reserve certain large-scale manufacturing capacity to pave the way for commercial manufacturing of Janssen’s adenovirus-based COVID-19 vaccine beginning in 2021.
  • March 30, 2020 - Johnson & Johnson has identified a lead COVID-19 vaccine candidate (with two back-ups), which will progress into the first manufacturing steps. Under an accelerated timeline, the Company is aiming to initiate a Phase 1 clinical study in September 2020, with clinical data on safety and efficacy expected to be available by the end of the year. This could allow vaccine availability for emergency use in early 2021. For comparison, the typical vaccine development process involves a number of different research stages, spanning 5 to 7 years, before a candidate is even considered for approval.

Ad26.COV2-S (JNJ-78436735) Vaccine Clinical Trials

Clinical Trial NCT04436276: - Phase 1/2 - last updated on October 20, 2020.

  • The purpose of the study is to assess the safety, reactogenicity, and immunogenicity of Ad26COVS1 (JNJ-78436735) at 2 dose levels, administered intramuscularly (IM) as a single-dose or 2-dose schedule, with a single booster vaccination administered in one cohort, in healthy adults aged greater than or equal to 18 to less than or equal to 55 years and in adults aged greater than or equal to 65 years in good health with or without stable underlying conditions.
  • The study took place in the USA and Belgium.

Clinical Trial NCT04505722: Study code: VAC31518COV3001: Phase 3 study - last updated on October 28, 2020.

  • The approved clinical trial is a phase 3, randomized, double-blind, placebo-controlled study to assess the efficacy and safety of Ad26.COV2.S in preventing Sars-CoV-2-mediated Covid-19 in adults aged 18 years or older (). It will be a single dose of the vaccine or placebo.
  • The study foresees the inclusion of up to 60,000 volunteers, across 3 continents, with seven thousand in Brazil, distributed in several regions of the country in the states of São Paulo, Rio Grande do Sul, Rio de Janeiro, Paraná, Minas Gerais, Bahia, and Rio Grande do Norte.
  • Protocol VAC31518COV3001; Phase 3 AMENDMENT 1 VAC31518 (JNJ-78436735).