A: 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 determined the totality of available data provides clear evidence that Janssen COVID-19 Vaccine may be effective in preventing COVID-19. Based on the scientific evidence available at the time, the FDA concluded 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 FDA limited the use of the Janssen COVID-19 Vaccine to individuals 18 years of age and older for whom other authorized or approved COVID-19 vaccines are not accessible or clinically appropriate, and to individuals 18 years of age and older who elect to receive the Janssen COVID-19 Vaccine because they would otherwise not receive a COVID-19 vaccine for the following reasons: 

• There is a risk of thrombosis with thrombocytopenia syndrome (TTS), a syndrome of rare and potentially life-threatening blood clots in combination with low levels of blood platelets with onset of symptoms approximately one to two weeks following administration of the Janssen COVID-19 Vaccine.
• After conducting an updated analysis, evaluation and investigation of reported cases of TTS, the FDA determined the risk of TTS following administration of the Janssen COVID-19 Vaccine, warrants limiting the authorized use of the vaccine.
• The FDA considered that individuals with TTS may rapidly deteriorate, despite prompt diagnosis and treatment, that TTS can lead to long-term and debilitating health consequences and that TTS has a high death rate. FDA also considered the availability of alternative authorized and approved COVID-19 vaccines which provide protection from COVID-19 and have not been shown to present a risk for TTS.
• The FDA determined the known and potential benefits of the vaccine for the prevention of COVID-19 outweigh the known and potential risks for individuals 18 years of age and older for whom other authorized or approved COVID-19 vaccines are not accessible or clinically appropriate, and for individuals 18 years of age and older who elect to receive the Janssen COVID-19 Vaccine because they would otherwise not receive a COVID-19 vaccine.

The Fact Sheet for Healthcare Providers Administering Vaccine was revised to reflect the authorized use of the Janssen COVID-19 Vaccine and includes a warning statement at the beginning of the fact sheet for prominence, summarizing information on the risk for TTS. Additionally, information on the revision to the authorized use of the vaccine and updated information on this risk of blood clots with low levels of blood platelets has been added to the Fact Sheet for Recipients and Caregivers. 

A: The Janssen COVID-19 Vaccine can cause thrombosis with thrombocytopenia syndrome (TTS) which may be life-threatening.  

In people who have developed TTS following the Janssen COVID-19 Vaccine, symptoms began approximately 1 to 2 weeks following vaccination. Reporting of these blood clots with low blood platelets have been reported in males and females, in a wide age range of individuals 18 years of age and older, with the highest reporting rate (approximately 8 cases per 1,000,000 doses administered) in females ages 30- 49 years; overall about 15% of cases have been fatal. 

You should seek medical attention right away 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 the commonly reported side effects are mild to moderate in severity and last 1 to 2 days.  

A: In people who developed these blood clots with low levels of blood platelets, symptoms began approximately one to two weeks after vaccination.

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.

Additionally, the American Society of Hematology has information relevant to the diagnosis and treatment of thrombosis with thrombocytopenia following the Janssen COVID-19 Vaccine.

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: The duration of protection against COVID-19 is currently unknown.

 

A: It is not known if Janssen COVID-19 Vaccine protects against asymptomatic SARS-CoV-2 infection.

A: Yes. Among the participants in the study the 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: The limited authorized use of the Janssen COVID-19 Vaccine is also applicable to booster dosing. In individuals 18 years of age and older for whom other authorized or approved COVID-19 vaccines are not accessible or clinically appropriate, and in individuals 18 years of age and older who elect to receive the Janssen COVID-19 Vaccine because they would otherwise not receive a COVID-19 vaccine, a single booster dose of the Janssen COVID-19 Vaccine may be administered:

• at least 2 months after completion of primary vaccination with the Janssen COVID-19 Vaccine 
• following completion of primary vaccination with a different authorized or approved COVID-19 vaccine, using the dosing interval 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 vaccine used for 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.

It is important to note that as a general matter, while some individuals may experience side effects following any vaccination, not every individual’s experience will be the same and some people may not experience side effects.

A: Based on FDA’s analysis of data from the Vaccine Adverse Event Reporting System (VAERS) and our review of an analysis of data conducted by Janssen, the FDA determined that the currently available data suggest an increased risk of Immune Thrombocytopenia (ITP) during the 42 days following administration of the Janssen COVID-19 Vaccine. ITP is a disorder that can cause easy or excessive bruising and bleeding due to very low levels of platelets. ITP 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. 

Specifically, the Fact Sheet for HealthCare Providers Administering Vaccine (Vaccination Providers) has been revised to include a warning about ITP. The warning states that reports of adverse events following use of the vaccine suggest an increased risk of ITP during the 42 days following vaccination, and that individuals with a history of ITP should discuss with their healthcare provider the risk of ITP and the potential need for platelet monitoring following vaccination with the Janssen COVID-19 Vaccine.  

The Fact Sheet for Recipients and Caregivers has been revised to inform about ITP and instructs individuals who have ever had a diagnosis of ITP to talk to their vaccination provider before receiving the Janssen COVID-19 Vaccine. It also conveys that vaccine recipients should seek medical attention right away if any of the following symptoms develop after receiving the Janssen COVID-19 Vaccine:

• easy or excessive bruising or tiny blood spots under the skin beyond the site of the injection,
• unusual or excessive bleeding

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). 

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). The 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. At the time, the available data suggested the chance of this serious adverse event occurring was remote, but investigation into the level of potential excess risk due to vaccination and specific risk factors continued.

At that time, the Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers) was revised to include 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. Based on data available at the time, the warning also noted that reporting of these blood clots with low levels of platelets had 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 was also revised to include information about blood clots in combination with low blood platelets after receiving the Janssen COVID-19 Vaccine.

We informed the public of these cases and noted that a causal relationship with Janssen COVID-19 Vaccine is plausible for TTS. The FDA and CDC  continues to fully investigate all reports of suspected TTS and to closely monitor the safety of all COVID-19 vaccines.

A: Monitoring the safety of the Janssen COVID-19 Vaccine continues and reports to the Vaccine Adverse Events Reporting System (VAERS), a passive surveillance system, provide evidence for an increased risk of blood clots in combination with low blood platelets (thrombosis with thrombocytopenia syndrome (TTS)) with onset of symptoms approximately one to two weeks after administration of the Janssen COVID-19 Vaccine.

The Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers) was revised to include a Contraindication to the administration of the Janssen COVID-19 Vaccine to individuals with a history of thrombosis with thrombocytopenia following the Janssen COVID-19 Vaccine or any other adenovirus-vectored COVID-19 vaccine, such as AstraZeneca’s COVID-19 vaccine (which is not authorized or approved by the FDA). The Warning section was updated to include the most current information about the risk of TTS following administration of the Janssen COVID-19 Vaccine.  Specifically, it informed that cases of TTS following administration of the Janssen COVID-19 Vaccine have been reported in males and females, in a wide age range of individuals 18 years of age and older, with the highest reporting rate (approximately 1 case per 100,000 doses administered) in females ages 30- 49 years; and about 15% of cases have been fatal. The Fact Sheet was revised to also convey that currently available evidence supports a causal relationship between TTS and the Janssen COVID19 Vaccine.

The Fact Sheet for Recipients and Caregivers was revised to inform potential vaccine recipients that they should not receive Janssen COVID-19 Vaccine if they have had a blood clot along with low blood platelets following Janssen COVID-19 Vaccine or following AstraZeneca’s COVID-19 vaccine, which is not authorized or approved by the FDA, and to include the most current information about the occurrence of blood clots in combination with low blood platelets after receiving the Janssen COVID-19 Vaccine.

The FDA and CDC continue to investigate the level of potential excess risk of TTS 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 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 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 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: 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, as long as these are individuals for whom other FDA-authorized or approved COVID-19 vaccines are not accessible or clinically appropriate or who elect to receive the Janssen COVID19 Vaccine because they would otherwise not receive a COVID-19 vaccine. The FDA has determined the totality of available data provides clear evidence that Janssen COVID-19 Vaccine may be effective in preventing COVID-19. The data also show the known and potential benefits outweigh the known and potential risks of the vaccine in the authorized population. Among participants 60 years of age and older with health conditions 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, currently available evidence supports a causal relationship between thrombosis with thrombocytopenia (TTS) and the Janssen COVID-19 Vaccine.

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 administration of 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 the 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 the 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 – is 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 the 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.

Current scientific evidence suggests that individuals previously infected with SARS-CoV-2, including individuals who have had COVID-19, may be at risk of reinfection and developing COVID-19 again and may benefit from vaccination. Furthermore, available data suggest that the safety profile of the vaccine does not differ between previously infected individuals and 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: The FDA makes numerous materials about the Janssen COVID-19 Vaccine available to the public. These materials include fact sheets, materials covering regulatory information, frequently asked questions, press releases, translations and more. All the materials about the Janssen COVID-19 Vaccine can be found on the Janssen COVID-19 Vaccine webpage. In addition, the FDA posts all the materials for the COVID-19 vaccine emergency use authorizations on the Emergency Use Authorization webpage.

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 the emergency use authorization request met the criteria for issuing an EUA. The FDA’s former 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.