Janssen COVID-19 Vaccine Frequently Asked Questions
April 23, 2021: The FDA amended the emergency use authorization of the Johnson & Johnson (Janssen) COVID-19 vaccine to include information about a very rare and serious type of blood clot in people who receive the vaccine.
Report vaccine side effects toll-free at 1-800-822-7967 or online to FDA/CDC Vaccine Adverse Event Reporting System (VAERS).
On February 27, 2021, the U.S. Food and Drug Administration issued an emergency use authorization (EUA) for the third vaccine for the prevention of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The EUA allows Janssen COVID-19 Vaccine to be distributed in the U.S for use in individuals 18 years of age and older.
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. It is administered as a single-dose.
The FDA evaluated and analyzed the safety and effectiveness data from clinical trials conducted in over 40,000 thousand 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. The data also show that that the known and potential benefits outweigh the known and potential risks of the vaccine’s use in millions of people 18 years of age and older, including healthy individuals.
On April 13, 2021, the FDA and CDC recommended a pause in the use of Janssen COVID-19 Vaccine due to reports of serious adverse events of a type of blood clot in the large blood vessels in the brain called cerebral venous sinus thrombosis (CVST) in combination with low levels of blood platelets (blood cells that help the body stop bleeding). Thrombosis (blood clots) with thrombocytopenia (low levels of blood platelets) is also referred to as thrombosis with thrombocytopenia syndrome.
The FDA and CDC have reviewed all of the available data, including new information since our recommendation to pause the use of the vaccine. 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. At this time, the available data suggest that the chance of this serious adverse event occurring is very low, but investigation into the level of potential excess risk due to vaccination is ongoing.
The Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers) has been updated to include a Warning pertaining to the risk of thrombosis with thrombocytopenia. The Fact Sheet for Recipients and Caregivers has also been updated to include information about these serious adverse events.
We will continue to closely monitor the safety of the Janssen COVID-19 Vaccine.
Yes. Specifically, as of April 21, 2021, 15 cases of thrombosis with thrombocytopenia following Janssen COVID-19 Vaccine have now been confirmed, involving cerebral venous sinuses and other sites in the body (including, but not limited to the large blood vessels of the abdomen and the veins of the legs) and these have been associated with three deaths. These numbers will likely change over time as additional cases are reported and investigated.
We are informing the public of these cases and note that a causal relationship with Janssen COVID-19 Vaccine is plausible for thrombosis with thrombocytopenia syndrome and we are continuing to monitor the safety of the vaccine and investigating all reports. Specific risk factors for thrombosis with thrombocytopenia syndrome following the Janssen COVID-19 Vaccine and the level of potential excess risk due to vaccination are under investigation.
At the time, the FDA and CDC had reviewed data involving six cases (including one death) reported to the Vaccine Adverse Event Reporting System (VAERS) of rare types of blood clots in combination with low blood platelets (now referred to as thrombosis with thrombocytopenia syndrome). At that time, all cases occurred in females ranging in age from 18 through 48 years and involved blood clots in the large blood vessels of the brain (CVST). In some of the reported cases of CVST, blood clots also involved large veins in the abdomen.
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 thrombosis with thrombocytopenia syndrome.
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. The FDA and CDC will continue to fully investigate all reports to determine if a causal relationship exists.
At this time, the available data suggest that the chance of these adverse events occurring is remote, but investigation into the level of potential excess risk due to vaccination is ongoing. We are also continuing to closely monitor the safety of the vaccine, as we are doing with all COVID-19 vaccines.
In people who have developed blood clots with low levels of platelets following the Janssen COVID-19 Vaccine, symptoms began approximately 1 to 2 weeks following vaccination.
You should contact your health care provider immediately if you are experiencing any of the following symptoms:
- shortness of breath
- chest pain
- leg swelling
- persistent abdominal pain
- neurological symptoms (including 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 distinct 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.
Healthcare providers should be alert to the signs and symptoms of thrombosis with thrombocytopenia syndrome 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.
The effectiveness data to support the 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, 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.
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.
Efficacy of the Janssen COVID-19 vaccine demonstrated in the clinical trial reflected protection against several emerging SARS-CoV-2 variants of concern, 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).
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.
Yes. 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.
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.
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.
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.
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 was 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 include 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 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.
It is mandatory for Janssen Biotech, Inc. and vaccination providers to report the following to the Vaccine Adverse Event Reporting System (VAERS) for Janssen COVID-19 Vaccine:
- Serious adverse events
- Cases of Multisystem Inflammatory Syndrome (MIS)
- Cases of COVID-19 that result in hospitalization or death
It is also mandatory for vaccination providers to report all vaccine administration errors, whether or not associated with an adverse event, to VAERS for which they become aware, and for Janssen Biotech, Inc. to include a summary and analysis of all identified vaccine administration errors in monthly safety reports submitted to the FDA.
Janssen Biotech, Inc. has submitted a pharmacovigilance plan to 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.
In addition, the FDA, CDC, and other federal partners are using robust systems and data sources to conduct ongoing safety monitoring for COVID-19 vaccines authorized under an EUA. 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 – 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 period. Some of these systems are VAERS, the Vaccine Safety Datalink (VSD), the Biologics Effectiveness and Safety (BEST) Initiative, and Medicare claims data.
While relatively few confirmed COVID-19 cases occurred overall among participants with evidence of infection prior to vaccination, 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.
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.
No, there are no data available to support this scenario.