Janssen COVID-19 Vaccine Frequently Asked Questions
A: Janssen COVID-19 Vaccine is authorized to prevent coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals 18 years of age and older. Primary vaccination with the Janssen COVID-19 Vaccine consists of a single dose.
For the February 2021 emergency use authorization, the FDA evaluated and analyzed the safety and effectiveness data from clinical trials conducted in over 40,000 study participants and manufacturing information submitted by Janssen Biotech, Inc. The FDA has determined that the totality of the available data provides clear evidence that Janssen COVID-19 Vaccine may be effective in preventing COVID-19. Based on the scientific evidence available, the FDA concluded that the known and potential benefits of Janssen COVID-19 Vaccine outweigh the known and potential risks for people 18 years of age and older.
A: The effectiveness data to support the February 2021 EUA include an analysis of 39,321 participants in the ongoing randomized, placebo-controlled study being conducted in South Africa, certain countries in South America, Mexico, and the U.S. who did not have evidence of SARS-CoV-2 infection prior to receiving the vaccine. Among these participants, 19,630 received the vaccine and 19,691 received placebo. Overall, among these clinical trial participants, primary vaccination with a single-dose of the vaccine was approximately 67% effective in preventing moderate to severe/critical COVID-19 disease occurring at least 14 days after vaccination and 66% effective in preventing moderate to severe/critical disease at least 28 days after vaccination.
Additionally, the vaccine was approximately 77% effective in preventing severe/critical COVID-19 occurring at least 14 days after vaccination and 85% effective in preventing severe/critical COVID-19 occurring at least 28 days after vaccination.
For the vaccine and placebo groups, respectively, there were 116 and 348 COVID-19 cases that occurred at least 14 days after vaccination, and 66 and 193 cases that occurred at least 28 days after vaccination. Starting 14 days after vaccination, there were 14 severe/critical cases in the vaccinated group versus 60 severe/critical cases in the placebo group, and starting 28 days after vaccination, there were 5 severe/critical cases in the vaccine group versus 34 severe/critical cases in the placebo group.
A: Data are not yet available to inform about the duration of protection that the vaccine will provide.
A: It is not known if the vaccine protects against asymptomatic SARS-CoV-2 infection.
A: Yes. Among the participants in the study that FDA evaluated for the February 2021 authorization, overall, 45.3% of participants in the clinical trials identify as Hispanic/Latino, 19.4% Black or African American, 9.5% American Indian or Alaska Native, 3.3% Asian, 0.2% Native Hawaiian or other Pacific Islander, and 5.6% Multiracial.
The demographic characteristics were similar among participants who received Janssen COVID-19 Vaccine and those who received placebo.
A: Information is available for the United States, South Africa, and Brazil. A subgroup analysis was conducted for these countries. Following are the results of this analysis:
- United States: the vaccine was 74.4% effective and 72% effective in preventing moderate to severe/critical COVID-19 occurring at least 14 days and 28 days after vaccination, respectively.
- South Africa: the vaccine was 52.0% effective and 64.0% effective in preventing moderate to severe/critical COVID-19 occurring at least 14 days and 28 days after vaccination, respectively.
- Brazil: the vaccine was 66.2% effective and 68.1% effective in preventing moderate to severe/critical COVID-19 occurring at least 14 days and 28 days after vaccination, respectively.
A: Efficacy of the Janssen COVID-19 vaccine demonstrated in the clinical trial reflected protection against several SARS-CoV-2 variants predominant during the trial, including the Wuhan-H1 variant D614G (predominant in the United States), the B.1.351 variant (predominant in South Africa), and a P.2 variant (predominant in Brazil).
A: A single booster dose may be administered at least 2 months after completion of primary vaccination with the Janssen COVID-19 Vaccine in individuals 18 years of age and older. A single booster dose may be administered to individuals 18 years of age and older as a heterologous booster dose following completion of primary vaccination with a different authorized or approved COVID-19 vaccine. The dosing interval for the heterologous booster dose is the same as that authorized for a booster dose of the vaccine used for primary vaccination.
A: The authorization for emergency use of a single booster dose of the Janssen COVID-19 Vaccine is based on the FDA’s evaluation of immune response data in 39 participants from a clinical trial including 24 participants who were 18 through 55 years of age and 15 participants who were 65 years of age and older. The study participants received a booster dose approximately 2 months after their first dose, and the results demonstrated a booster response.
Overall, approximately 9,000 clinical trial participants have received 2 doses of Janssen COVID-19 Vaccine administered at least 2 months apart, and approximately 2,700 participants have had at least 2 months of safety follow-up after the booster dose. Janssen’s analyses of data from these studies have not identified new safety concerns.
The authorization for emergency use of a single booster dose of the Janssen COVID-19 Vaccine in individuals who completed primary vaccination with a different authorized or approved COVID-19 vaccine (heterologous booster dose) is based on the above-mentioned data as well as immunogenicity data from a clinical trial that evaluated a heterologous booster dose of the Janssen COVID-19 Vaccine. In this study, adults who had completed primary vaccination with a Moderna COVID-19 Vaccine (151 participants), a Janssen COVID-19 Vaccine (156 participants), or a Pfizer-BioNTech COVID-19 Vaccine (151 participants) received a booster dose of one of three vaccines: Moderna COVID-19 Vaccine, Janssen COVID-19 Vaccine, or Pfizer-BioNTech COVID-19 Vaccine. A booster response to the Janssen COVID-19 Vaccine was demonstrated regardless of primary vaccination.
A: The available safety data to support the EUA include an analysis of 43,783 participants enrolled in an ongoing randomized, placebo-controlled study being conducted in South Africa, certain countries in South America, Mexico, and the U.S. These participants, 21,895 of whom received the vaccine and 21,888 of whom received saline placebo, were followed for a median duration of eight weeks after vaccination. The most commonly reported side effects were pain at the injection site, headache, fatigue, muscle aches and nausea. Most of these side effects were mild to moderate in severity and lasted 1-2 days.
A: As a result of ongoing safety monitoring, on April 13, 2021, the FDA and CDC recommended a temporary pause in the use of Janssen COVID-19 Vaccine, due to reports of a serious and rare type of blood clot in combination with low blood platelets (blood cells that help your body stop bleeding). This serious condition is called thrombosis with thrombocytopenia syndrome (TTS).
Out of an abundance of caution, the FDA and CDC recommended a pause in the use of the Janssen COVID-19 Vaccine while the FDA and CDC investigated these reports of serious adverse events. This was important, in part, to help ensure that health care providers were made aware of the potential for these adverse events and could plan for proper recognition and management due to the unique treatment required for TTS.
The safety monitoring program that is in place to monitor COVID-19 vaccines is working, as we were able to detect the reports of these serious adverse events early and take action to assess them.
A: On April 23, 2021, the FDA and CDC lifted the recommended pause on the Janssen COVID-19 Vaccine after a thorough evaluation of the available safety data pertaining to thrombosis with thrombocytopenia syndrome (TTS). Those data, plus the deliberations and recommendations of CDC’s Advisory Committee on Immunization Practices (ACIP), helped with our assessment that the known and potential benefits of Janssen COVID-19 Vaccine outweigh its known and potential risks in individuals 18 years of age and older. The available data suggest that the chance of this serious adverse event occurring is remote, but investigation into the level of potential excess risk due to vaccination and specific risk factors is ongoing.
The Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers) includes a Warning pertaining to the risk of TTS. The warning notes that in people who developed blood clots with low blood platelets after receiving the Janssen COVID-19 Vaccine, symptoms began about 1 to 2 weeks after vaccination. Reporting of these blood clots with low levels of platelets has been highest in females ages 18 through 49 years. Among reported cases of TTS, the blood clots have involved blood vessels in the brain, abdomen, and legs, as well as blood vessels at other body sites. The Fact Sheet for Recipients and Caregivers also includes information about blood clots in combination with low blood platelets after receiving the Janssen COVID-19 Vaccine.
We have informed the public of these cases and note that a causal relationship with Janssen COVID-19 Vaccine is plausible for TTS. The FDA and CDC will continue to fully investigate all reports of TTS and to closely monitor the safety of all COVID-19 vaccines.
A: The available data suggest that the chance of these adverse events occurring is remote.
In people who have developed blood clots with low blood platelets following the Janssen COVID-19 Vaccine, symptoms began approximately 1 to 2 weeks following vaccination. Reporting of these blood clots with low blood platelets has been highest in females ages 18 through 49 years.
You should contact your health care provider immediately if you are experiencing any of the following symptoms after receiving the Janssen COVID-19 Vaccine:
- shortness of breath
- chest pain
- leg swelling
- persistent abdominal pain
- severe or persistent headaches or blurred vision
- easy bruising
- tiny blood spots under the skin beyond the site of injection of the vaccine
These symptoms are different from the commonly reported side effects that people may experience in the first few days following vaccination, which can include headache, fatigue, muscle aches and nausea. Most of these side effects are mild to moderate in severity and last 1 to 2 days.
A: Healthcare providers should be alert to the signs and symptoms of thrombosis with thrombocytopenia syndrome (TTS) in individuals vaccinated with Janssen COVID-19 Vaccine. In individuals with suspected thrombosis with thrombocytopenia and who were vaccinated with Janssen COVID-19 Vaccine, heparin may be harmful and alternative treatments may be needed. Consultation with hematology specialists is strongly recommended.
Additional information for clinicians is available from CDC in its Health Alert Network notice, “Cases of Cerebral Venous Sinus Thrombosis with Thrombocytopenia after Receipt of the Johnson & Johnson COVID-19 Vaccine.”
In addition, The American Society of Hematology has information on its website relevant to the diagnosis and treatment of thrombosis with thrombocytopenia following the Janssen COVID-19 Vaccine.
A: Guillain Barré syndrome (a neurological disorder in which the body’s immune system damages nerve cells, causing muscle weakness and sometimes paralysis) has occurred in some people who have received the Janssen COVID-19 Vaccine. In most of these people, symptoms began within 42 days following receipt of the Janssen COVID-19 Vaccine. The chance of having this occur is very low. The Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers) includes a warning about the suggested increased risk of Guillain Barré Syndrome (GBS) and the Fact Sheet for Recipients and Caregivers includes information about GBS. The Fact Sheet for Recipients and Caregivers notes that vaccine recipients should seek medical attention right away if they experience any of the following symptoms after receiving the Janssen COVID-19 Vaccine:
- Weakness or tingling sensations, especially in the legs or arms, that’s worsening and spreading to other parts of the body
- Difficulty walking
- Difficulty with facial movements, including speaking, chewing, or swallowing
- Double vision or inability to move eyes
- Difficulty with bladder control or bowel function
A: No. The only way to accurately compare the effectiveness of medical products, such as vaccines or drugs, is by direct comparison in head-to-head clinical trials, which did not occur for these vaccines. Furthermore, the clinical trials for these vaccines occurred in different geographic regions and at different points in time with varying incidence of COVID-19. All of the COVID-19 vaccines that the FDA has authorized for emergency use are at least 50% more effective than placebo in preventing COVID-19, consistent with FDA recommendations provided in our October 2020 guidance document, Emergency Use Authorization for Vaccines to Prevent COVID-19. A vaccine with at least 50% efficacy would have a significant impact on disease, both at the individual and societal level.
A: There is no scientific evidence to suggest that the vaccine could cause infertility in women. In addition, infertility is not known to occur as a result of natural COVID-19 disease, further demonstrating that immune responses to the virus, whether induced by infection or a vaccine, are not a cause of infertility. Reports on social media have falsely asserted that the vaccine could cause infertility in women and the FDA is concerned that this misinformation may cause women to avoid vaccination to prevent COVID-19, which is a potentially serious and life-threatening disease. SARS-CoV-2 is the virus that causes COVID-19. The symptoms of COVID-19 vary and are unpredictable; many people have no symptoms or only mild disease, while some have severe respiratory disease including pneumonia and acute respiratory distress syndrome (ARDS), leading to multi-organ failure and death. The Janssen COVID-19 vaccine uses a type of adenovirus that cannot replicate to deliver a piece of the DNA, or genetic material, that is used to make the distinctive “spike” protein of the SARS-CoV-2 virus. After a person receives this vaccine, the body can temporarily make the spike protein, which does not cause disease, but triggers the immune system to learn to react defensively, producing an immune response against SARS-CoV-2. Contrary to false reports on social media, this protein is not the same as any involved in formation of the placenta.
A: While there have been no specific studies in these groups, there is no contraindication to receipt of the vaccine for pregnant or breastfeeding women. Pregnant or breastfeeding women should discuss their options with their healthcare providers.
A: Yes. The FDA has determined that the totality of the available data provides clear evidence that Janssen COVID-19 Vaccine may be effective in preventing COVID-19. The data also show that that the known and potential benefits outweigh the known and potential risks of the vaccine. Among these participants in the vaccine group of the clinical trial, there were no COVID-19-related deaths and no COVID-19 cases requiring medical intervention occurring 28 days or more after vaccination.
A: In the study that evaluated safety in 43,783 participants (21,895 of whom received the vaccine and 21,888 of whom received saline placebo), hives were reported in five vaccine recipients and 1 placebo recipient in the 7 days following vaccination. In this study, there has been one report of severe hypersensitivity reaction, not classified as anaphylaxis, beginning two days following vaccination with Janssen COVID-19 Vaccine. The event was serious and likely related to vaccination.
In another ongoing clinical study in South Africa, one case of anaphylaxis has been reported following administration of the vaccine.
The Fact Sheet for Healthcare Providers Administering Vaccine and the Prescribing Information includes the following information, and the same general information is also included in the COVID-19 Vaccine Fact Sheets for Healthcare Providers Administering Vaccine and the Prescribing Information for the other authorized COVID-19 vaccines:
CONTRAINDICATION
Do not administer the Janssen COVID-19 Vaccine to individuals with a known history of a severe allergic reaction (e.g., anaphylaxis) to a previous dose of the Janssen COVID-19 Vaccine or any component of the Janssen COVID-19 Vaccine (see Full EUA Prescribing Information).
WARNINGS
Appropriate medical treatment to manage immediate allergic reactions must be immediately available in the event an acute anaphylactic reaction occurs following administration of the Janssen COVID-19 Vaccine.
This information is also consistent with the Prescribing Information for all vaccines intended to prevent infectious diseases.
The Fact Sheet for Healthcare Providers Administering Vaccine and the Prescribing Information direct the reader to the Centers for Disease Control and Prevention’s guidelines for monitoring for allergic reactions following vaccination.
A: A serious adverse event of severe pain in the injected arm that began immediately after vaccination and that was ongoing 74 days following vaccination was reported in one vaccine recipient. A serious adverse event of severe generalized weakness, fever, and headache, with onset on the day following vaccination and resolution three days following vaccination was reported in one vaccine recipient. These serious adverse events are likely related to the vaccine.
Numerical imbalances, with more events in vaccine than placebo recipients, were observed for the following serious and non-serious adverse events of interest in individuals receiving the vaccine or placebo, respectively:
- Thromboembolic events:
- Deep vein thrombosis: 6 events (2 serious) in vaccine recipients versus 2 events (1 serious) in placebo recipients
- Pulmonary embolism: 4 events (3 serious) in vaccine recipients versus 1 event (serious) in placebo recipients
- Transverse sinus thrombosis with thrombocytopenia: 1 event (serious and with onset of symptoms 8 days post-vaccination) in vaccine recipients versus 0 in placebo recipients
- Seizures:
- 4 events (1 serious) in vaccine recipients versus 1 event (0 serious) in placebo recipients
- Tinnitus (ringing in one or both ears):
- 6 events (0 serious) in vaccine recipients versus 0 in placebo recipients
For these events, a causal relationship with the Janssen COVID-19 vaccine could not be determined based on the clinical trial. The assessment of causality was confounded by the presence of underlying medical conditions that may have predisposed individuals to these events. However, taking into consideration post-authorization experience, a causal relationship with Janssen COVID-19 Vaccine is plausible for thrombosis with thrombocytopenia and continues to be investigated.
A: Providers administering Janssen COVID-19 Vaccine must report to the Vaccine Adverse Event Reporting System (VAERS) and are encouraged to report to Janssen Biotech Inc. the following information associated with the vaccine of which they become aware:
- Vaccine administration errors whether or not associated with an adverse event
- Serious adverse events (irrespective of attribution to vaccination)
- Cases of Multisystem Inflammatory Syndrome (MIS) in adults
- Cases of COVID-19 that result in hospitalization or death
A: Janssen Biotech, Inc. has a pharmacovigilance plan that was assessed by FDA to monitor the safety of Janssen COVID-19 Vaccine. The pharmacovigilance plan includes a plan to complete longer-term safety follow-up for participants enrolled in ongoing clinical trials. The pharmacovigilance plan also includes other activities aimed at monitoring the safety of the vaccine and ensuring that any safety concerns are identified and evaluated in a timely manner.
Responsibility for additional post-authorization vaccine safety monitoring is shared primarily by FDA and the U.S. Centers for Disease Control and Prevention, along with other agencies involved in healthcare delivery. Post-authorization safety monitoring during the COVID-19 pandemic vaccination program aims to continuously monitor the safety of COVID-19 vaccines to rapidly detect safety problems if they exist. There are multiple, complementary systems in place with validated analytic methods that can rapidly detect signals for possible vaccine safety problems. The U.S. government has a well-established post-authorization/post-approval vaccine safety monitoring infrastructure that has been scaled up to meet the needs of a large-scale COVID-19 vaccination program. The U.S. government – in partnership with health systems, academic centers, and private sector partners – are using multiple existing vaccine safety monitoring systems to monitor COVID-19 vaccines in the post-authorization/approval period. Some of these systems are the Vaccine Adverse Event Reporting System (VAERS), the Vaccine Safety Datalink (VSD), the Biologics Effectiveness and Safety (BEST) Initiative, and Medicare claims data.
A: The EUA requires vaccination providers, prior to the individual receiving the vaccine, to communicate to the recipient or their caregiver information consistent with the “Fact Sheet for Recipients and Caregivers,” and either to provide a copy of the Fact Sheet for Recipients and Caregivers or to direct the individual to the website, www.janssencovid19vaccine.com. to obtain the fact sheet.
A: Yes. Among the participants in the study that FDA evaluated for the February 2021 authorization, relatively few confirmed COVID-19 cases occurred overall among clinical study participants with evidence of SARS-CoV-2 infection prior to vaccination, but limited data suggest that previously infected individuals can be at risk of COVID-19 (i.e., reinfection) and may benefit from vaccination. Furthermore, available data suggest that the safety profile of the vaccine in previously infected individuals is just as favorable as in previously uninfected individuals.
A: Most vaccines that protect from viral illnesses also reduce transmission of the virus that causes the disease by those who are vaccinated. While it is hoped this will be the case, the scientific community does not yet know if Janssen COVID-19 Vaccine will reduce such transmission.
A: Additional data on vaccine effectiveness will be generated from further follow-up of participants in clinical studies already underway before the EUA was issued, plus studies conducted by the manufacturer or by the U.S. government evaluating effectiveness of the vaccine as used under the EUA.
A: In a randomized, blinded clinical trial, participants are not aware of whether they received vaccine or placebo. Therefore, any mitigation efforts would have affected those who received vaccine and placebo equally. The relatively high number of COVID-19 cases occurring among placebo recipients suggests that any mitigation efforts among trial participants may not have been very effective at preventing COVID-19.
A:
- Fact Sheet for Recipients and Caregivers
- Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers), which also includes Emergency Use Authorization (EUA) Prescribing Information
- FDA Decision Memorandum for use in individuals 18 years of age and older
- FDA Decision Memorandum for a single booster dose in individuals 18 years of age and older
- FDA Decision Memorandum for heterologous booster dose
A: If safety or effectiveness concerns arise with a vaccine under EUA, the FDA has the authority to revoke the EUA. However, it is expected that the data supporting the EUA, together with those that will be collected during use of vaccine under EUA, and additional data collected from ongoing trials will be used to support licensure (approval) of a vaccine authorized under EUA.
A: The FDA believes it is important for clinical trials for other COVID-19 vaccines to continue or initiate. It is important to have a portfolio of COVID-19 vaccines available to be able to vaccinate our population.
A: FDA career scientists and physicians in the Center for Biologics Evaluation and Research made a determination that the emergency use authorization request met the criteria for issuing an EUA. The FDA’s chief scientist, Rear Adm. Denise Hinton, signed the letter of authorization.
A: The FDA embarked on an education campaign via social media, consumer content, media interviews, engagement with stakeholders and more to help the public understand our regulatory and scientific processes. These engagements will continue.