The U.S. Food and Drug Administration plays a critical role in protecting the U.S. from chemical, biological, radiological, nuclear (CBRN) attacks, and emerging infectious disease threats.
The FDA's roles in monkeypox preparedness and response during this public health emergency include:
- The FDA facilitates development and availability of medical products that can be used to diagnose, prevent, or treat monkeypox.
- The FDA works closely with product sponsors to clarify regulatory and data requirements necessary to rapidly advance development and availability of medical products essential to supporting response efforts.
- The FDA uses appropriate regulatory mechanisms to expedite access to medical products, such as under expanded access when circumstances warrant.
- The FDA also works with product sponsors and the scientific community to design efficient, well controlled trials to support the regulatory evaluation of investigational products.
- The FDA monitors for fraudulent products and false product claims related to CBRN and emerging infectious disease threats and takes appropriate action to protect consumers.
- September 7, 2022: Monkeypox Update: FDA Takes Significant Action to Help Expand Access to Testing
- September 7, 2022: FDA published new web pages about monkeypox and medical devices, including diagnostic testing, and authorized the first Emergency Use Authorization (EUA) for a monkeypox in vitro diagnostic.
- Monkeypox and Medical Devices
- Monkeypox Emergency Use Authorizations for Medical Devices, including new voluntary EUA templates for test developers
- Policy for Monkeypox Tests to Address the Public Health Emergency
- August 9, 2022: Monkeypox Update: FDA Authorizes Emergency Use of JYNNEOS Vaccine to Increase Vaccine Supply
- August 3, 2022: Tecovirimat and the Treatment of Monkeypox – Past, Present, and Future Considerations
- July 29, 2022: FDA Provides Update on Agency Response to Monkeypox Outbreak
- July 26, 2022: The FDA approved a supplement to the biologics license for the JYNNEOS Vaccine, which is approved to prevent smallpox and monkeypox, to allow for additional manufacturing capabilities at one of the plants where the vaccine is made. After expediting and completing an inspection of the plant earlier this month, the FDA has finished its evaluation of the required information to validate product quality and determined that the vaccine meets its quality standards.
- July 15, 2022: The FDA is advising people to use swab samples taken directly from a lesion (rash or growth) when testing for the monkeypox virus. The FDA is not aware of clinical data supporting the use of other sample types, such as blood or saliva, for monkeypox virus testing. Testing samples not taken from a lesion may lead to false test results.
- June 24, 2022: The FDA cleared the CDC Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set (K221834) for use in CDC-designated laboratories.
- June 10, 2022: The FDA cleared the use of additional reagents and automation to increase testing capacity of laboratories using the CDC test.
Monkeypox is a rare disease that is caused by infection with monkeypox virus. This virus can spread to anyone through close, personal, often skin-to-skin contact. Currently, a high rate of the known cases in the U.S. are among gay and bisexual men and transgender and non-binary people, but this virus is not limited by sexuality or gender.
Please see the Centers for Disease Control and Prevention’s page 2022 United States Monkeypox Response for the latest response information
At this time, public health authorities have not recommended the general public needs to be vaccinated against monkeypox. Public health authorities have only recommended select individuals receive vaccination. For example, vaccination is recommended for those who have been exposed to monkeypox and for individuals with certain risk factors. Refer to the CDC’s recommendations, Considerations for Monkeypox Vaccination, for specific information.
Individuals who received a smallpox vaccine may have some protection against monkeypox. However, there are several factors that could affect whether immunity was actually present, including the “take” (the lesion that develops at the site of inoculation) of the vaccine when administered and the time since vaccination.
Yes. Moreover, since monkeypox was first detected in the U.S., the FDA is working closely with the CDC, commercial laboratories, and traditional manufacturers to make monkeypox tests more readily available to patients and providers.
There is only one FDA-cleared test, the CDC’s Non-variola Orthopoxvirus Real-time PCR Primer and Probe Set (K221834), for use in CDC-designated laboratories and it uses swab samples taken directly from a lesion (rash or growth). The FDA is not aware of clinical data supporting the use of other sample types, such as blood or saliva, for monkeypox virus testing.
There are no FDA-approved treatments for monkeypox. However, the CDC holds an expanded access Investigational New Drug (EA-IND) protocol, sometimes called “compassionate use,” that allows for use of an antiviral medication called TPOXX (tecovirimat) for treatment of monkeypox. The safety and efficacy of TPOXX to treat monkeypox in humans has not been established.
Expanded access is a pathway for a patient with a serious or immediately life-threatening disease or condition to gain access to an investigational medical product for treatment outside of clinical trials when no comparable or alternative therapy options are available. For more information, please see FDA’s website at: https://www.fda.gov/news-events/public-health-focus/expanded-access.
At this time, the CDC is not aware of any monkeypox cases in the current outbreak that have been associated with handling or eating food.
In general, you should wash your hands after handling food packaging, after removing food from the packaging, before you prepare food for eating, and before you eat. Consumers can follow the CDC guidelines on frequent hand washing with soap and water for at least 20 seconds; and frequently clean and disinfect surfaces.
- It is always important to follow the four steps of food safety—clean, separate, cook, and chill.
Monkeypox can spread to anyone through close, personal, often skin-to-skin contact, including:
- Direct contact with monkeypox rash, scabs, or body fluids from a person with monkeypox.
- Touching objects, fabrics (clothing, bedding, or towels), and surfaces that have been used by someone with monkeypox.
- Contact with respiratory secretions.
For more information, see: How it Spreads | Monkeypox | Poxvirus | CDC
A person with monkeypox can spread it to others from the time symptoms start until the rash has fully healed and a fresh layer of skin has formed. The illness typically lasts 2-4 weeks. The CDC recommends that people with monkeypox remain isolated at home or at another location for the duration of illness.
Monkeypox can be spread by touching objects, fabrics (clothing or towels), and surfaces that have been used by someone with monkeypox.
Anyone handling, preparing and serving food should always follow safe food handling procedures, such as washing hands and surfaces often.
The FDA approved JYNNEOS Vaccine in 2019, for the prevention of smallpox and monkeypox disease in adults 18 years of age and older determined to be at high risk for smallpox or monkeypox infection.
- This is the only currently FDA-approved vaccine for the prevention of monkeypox disease.
- The vaccine does not contain the viruses that cause smallpox or monkeypox.
- Given the emerging public health need, the FDA and government partners worked to accelerate submission of information needed to make additional U.S. doses of JYNNEOS available much more quickly than scheduled.
- The vaccine is part of the Strategic National Stockpile, overseen by the Department of Health and Human Services’ Assistant Secretary for Preparedness and Response, which helps ensure that the vaccine is accessible in the U.S. if needed.
- Get the Fast Facts on the Intradermal JYNNEOS Monkeypox Vaccine, Simplified Chinese, Korean, Tagalog, Vietnamese, Spanish
Currently, there are no FDA-approved treatments for monkeypox; however, TPOXX (tecovirimat), an antiviral medication, is being made available through a randomized controlled clinical trial sponsored by the National Institutes of Allergy and Infectious Diseases (NIAID) and also through the CDC under an FDA authority called Expanded Access, or “compassionate use.”
TPOXX (tecovirimat) history:
As background, in 2018, the FDA approved TPOXX for treatment of smallpox in adults and children. Because smallpox is eradicated globally, the FDA approved TPOXX under “Animal Rule” regulations, as it was neither ethical nor feasible to test the efficacy of the drug in humans. TPOXX was approved for treatment of smallpox based on efficacy data obtained from animal studies, specifically non-human primates infected with monkeypox virus and rabbits infected with rabbitpox virus. Such studies were relevant since the viruses that cause smallpox, monkeypox, and rabbitpox are in the same family of viruses called “orthopoxviruses.” Safety data was obtained in healthy human volunteers without a smallpox or monkeypox infection.
Unlike smallpox, monkeypox was endemic in other parts of the world (e.g., the Democratic Republic of the Congo) at the time of TPOXX’s initial approval. Consequently, it remained both ethical and feasible to conduct clinical trials in humans to study TPOXX for the treatment of monkeypox disease. Therefore, TPOXX for the treatment of monkeypox disease was not appropriate for approval under the pathway described in the FDA’s Animal Rule regulations.
TPOXX as a treatment for monkeypox infections:
The safety and efficacy of TPOXX to treat monkeypox in humans has not been established. Conducting randomized, controlled trials to assess TPOXX’s safety and efficacy in humans with monkeypox infections is essential. We don’t currently know if TPOXX will be beneficial in treating patients with monkeypox, since drugs that are effective in animal studies are not always effective in humans.
On September 8, 2022, NIAID opened a randomized, controlled clinical trial to assess the safety and efficacy of TPOXX for the treatment of monkeypox infection. Health care providers should encourage their patients with monkeypox infection to be evaluated for enrollment in this trial. For patients for whom enrollment in this trial is not feasible (e.g., a clinical trial site is not geographically accessible), use of tecovirimat under CDC’s expanded access protocol should be consistent with applicable guidelines for tecovirimat use.
Risk of Viral Resistance to TPOXX:
Viruses can change over time. Sometimes these changes make antiviral drugs less effective at combating the virus they are targeting, meaning those drugs won’t work as well or might not work at all.
TPOXX works by inhibiting a viral protein, called VP37, that all orthopoxviruses (e.g., smallpox virus, monkeypox virus, vaccinia virus) share. However, as noted in the drug label, TPOXX has a low barrier to viral resistance. This means small changes to the VP37 protein could have a large impact on the antiviral activity of TPOXX.
CDC scientists are actively monitoring for changes in the monkeypox virus that could make the virus less susceptible to TPOXX. Because of the potential for the virus to become resistant to TPOXX, it is important the drug be used in a judicious manner.
Patients should enroll in NIAID’s randomized, controlled clinical trial when feasible to facilitate assessment of the safety, efficacy, and resistance profile of TPOXX. For patients for whom enrollment in a randomized clinical trial is not feasible (e.g., a clinical trial site is not geographically accessible), use of TPOXX under CDC’s expanded access protocol should be consistent with applicable guidelines for TPOXX use.
Information for the Scientific Community:
On September 12, 2022, the FDA released additional information in publicly posted reviews supporting approval of the new drug application for tecovirimat to describe specific changes in the VP37 proteins of orthopoxviruses (e.g., vaccinia virus and monkeypox virus) that are associated with tecovirimat drug resistance.
As described in the FDA reviews, multiple independent studies characterized tecovirimat resistance development in orthopoxviruses in cell culture studies, in animal studies, and in an anecdotal human case of progressive vaccinia. These studies identified several genetic pathways for orthopoxviruses to become resistant to tecovirimat, which involves the emergence of amino acid substitutions in the viral VP37 drug target (see Table below). Many of the resistance pathways require only a single amino acid change in VP37 to cause a substantial reduction in tecovirimat antiviral activity.
Table: Orthopoxvirus VP37 Amino Acid Substitutions Associated with Tecovirimat Resistance
|Resistance Analysis Study||Amino Acid Substitutions|
|VP37 amino acid substitutions associated with high-level phenotypic resistance to tecovirimat in cell culture (defined as ≥10-fold increase in EC50 value) in vaccinia virus, cowpox virus or camelpox virus
Single amino acid substitutions: H238Q, N267D/S, G277C, D283G/Y, A290V, D294V, A295E, L302P/Q
Combinations of amino acid substitutions: F25V+I372N, L178S+Y258C, N179H+D283G, H194N +303insSVK, N267D+I309T, N267S+I317V, G277C+I372N, D280G+D294G, A290V+L315M, K68N+Y258C+T308S, W2C+D225A+Y258C+D280G
|VP37 amino acid substitutions detected in monkeypox virus infected, tecovirimat-treated nonhuman primates that succumbed to disease||H238Q, N267del/I/D/S/K, R268G, D280Y, A290V, A295E, L297ins, I372N/ILKIKNRK (mutation of stop codon and extension of reading frame)
|VP37 amino acid substitutions detected in a tecovirimat-treated individual with progressive vaccinia virus infection
|1Due to the conserved nature of VP37, tecovirimat resistance-associated substitutions in one orthopoxvirus are expected to apply to other orthopoxviruses.|
Collectively, these studies indicate tecovirimat has a low barrier to resistance, and this must be considered in the context of the current monkeypox public health emergency because there is a risk that tecovirimat resistant virus could emerge and possibly spread.
The FDA is releasing this information to aid the scientific community’s genomic sequencing efforts to support national surveillance of the current monkeypox virus outbreak in the U.S. The FDA believes releasing this additional information will further facilitate the ability to monitor for the development and spread of tecovirimat-resistant virus and therefore is important in promoting public health.
For FDA Center for Drug Evaluation and Research (CDER) therapeutic product development questions, please contact: CDERPublicHealthEmergencyProductDevelopment@fda.hhs.gov
For information on medical devices, including monkeypox tests, please see: Monkeypox and Medical Devices.
Unfortunately, during emergency situations, fraudulent products claiming to prevent, treat or cure conditions associated with the emergency almost always appear for sale. The FDA monitors for fraudulent products and false product claims related to emerging infectious disease threats and takes appropriate action to protect consumers.
Moreover, the FDA has taken significant steps to combat misinformation about FDA-regulated products being communicated online, in the news, and by high-profile public officials, celebrities, and other outlets. We continue to look for opportunities to combat misinformation head-on in ways easy for consumers to understand and communicate the potential for real harm. Find trusted health information from the FDA and our government partners. See the resources below.
- U.S. Monkeypox 2022: Situation Summary (CDC)
- Fact sheet: Biden-Harris Administration’s Monkeypox Outbreak Response (White House, June 28, 2022)
- JYNNEOS Monkeypox Vaccine Distribution by Jurisdiction (HHS/ASPR)
- Information for health care professionals (CDC)
- Information for laboratory personnel (CDC)
- Information for veterinarians (CDC)
- Use of JYNNEOS (Smallpox and Monkeypox Vaccine, Live, Nonreplicating) for Preexposure Vaccination of Persons at Risk for Occupational Exposure to Orthopoxviruses: Recommendations of the Advisory Committee on Immunization Practices — United States, 2022 (CDC MMWR)
- Monkeypox (WHO)
- What are Medical Countermeasures (FDA)
Consumers and general information: contact FDA
You may also call 1-888-INFO-FDA / (1-888-463-6332)
For CDER therapeutic product development questions, please contact: CDERPublicHealthEmergencyProductDevelopment@fda.hhs.gov
- 1. 1Due to the conserved nature of VP37, tecovirimat resistance-associated substitutions in one orthopoxvirus are expected to apply to other orthopoxviruses.