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                MCM Issues

MCM Issues

                        Advanced Manufacturing
          Antimicrobial Resistance Information from FDA
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          FDA Mpox Response
          Medical Countermeasure Monitoring and Assessment
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          MCM Issues
          Smallpox Preparedness and Response Updates from FDAMCM Issues Smallpox Preparedness and Response Updates from FDA
  
  	
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              Photomicrograph demonstrating some of the histopathologic changes in a human skin tissue sample infected with the variola (smallpox) virus. (Credit: CDC)


  Caption
        
      Photomicrograph demonstrating some of the histopathologic changes in a human skin tissue sample infected with the variola (smallpox) virus. (Credit: CDC)What's new | Fast facts | FDA's role | Medical countermeasures | Guidance for industry | Advisory Committee meetings | Consumer protection | News and statements | Additional resources | Contact FDA

Information about FDA's response to mpox is available at: FDA Mpox Response.


What's new

**February 22, 2023:**On February 3, 2023, FDA approved a shelf-life extension of TPOXX (tecovirimat) Injection, 200 mg, from 24 months to 42 months for some lots of TPOXX injection. TPOXX supplied by the Strategic National Stockpile (SNS) does not have an expiration date printed on its label. To determine the expiration date for product received from the SNS, find the lot number on the product label and refer to this table to identify the corresponding expiration date.
	**May 18, 2022:**FDA approved an intravenous (IV) formulation (PDF, 565 KB) of TPOXX (tecovirimat) to treat smallpox. The oral formulation of the drug was originally approved in 2018. The IV formulation is an option for those who are unable to swallow the oral capsule. *Also see**Therapeutics**below*Fast Facts

Variola virus is the causative agent of smallpox.
	Smallpox was declared eradicated in 1980 by the World Health Organization, with no known cases of naturally occurring smallpox having occurred since 1977. The last outbreak of smallpox in the United States occurred in 1949.
	While there is no known immediate, direct threat of a biological attack using smallpox (i.e., an intentional release of Variola virus), concerns over the possible use of Variola virus in a biological attack have led to increased preparedness efforts.
	**Transmission:**Smallpox can be transmitted person-to-person via inhalation of virus-containing airborne droplets of saliva from an infected person. Transmission can also occur via contact with material from the smallpox pustules or crusted scabs, or through materials such as bedding or clothing that has been in contact with the pustules or scabs.
	**Prevention:**Smallpox can be prevented by vaccination with smallpox vaccine. The vaccine does not contain the smallpox virus and cannot give you smallpox. *Also see* *Vaccinesbelow*
	**Treatment:**Treatment of patients with smallpox generally involves supportive care. TPOXX (tecovirimat) and Tembexa (brincidofovir) are approved for the treatment of smallpox. *Also see* *Therapeutics**below*FDA's role

FDA plays a critical role in protecting the United States from chemical, biological, radiological, nuclear (CBRN), and emerging infectious disease threats.

FDA's roles in smallpox preparedness and response include:

**Facilitating the development and availability of medical countermeasures (MCMs)**that can be used to diagnose, prevent, or treat smallpox. *Also see Medical countermeasures and Guidance for industry below, and What are medical countermeasures*?
	**Working with medical product sponsors**to clarify regulatory and data requirements necessary to rapidly advance development of MCMs essential to supporting response efforts.
	**Protecting the safety of the nation’s blood supply**and human cells, tissues, and cellular/tissue-based products for transplantation. *Also see**Guidance for industry* *below*
	**Enabling access to investigational MCMs**—when necessary—through an appropriate regulatory mechanism such as under an Emergency Use Authorization (EUA) or under expanded access when the clinical circumstances warrant.
	**Protecting consumers against fraudulent products**- 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 CBRN and emerging infectious disease threats and takes appropriate action to protect consumers. *Also see Consumer protectionbelow*Medical countermeasures

Vaccines | Therapeutics | Diagnostics

Vaccines

Vaccination against smallpox before contact with the Variola virus can protect you from getting sick. Vaccination within 7 days of being exposed to Variola virus may provide protection from disease and, if you still get smallpox, may reduce the severity of disease. Currently, smallpox vaccine is not available to the general public because smallpox has been eradicated, and the virus no longer exists in nature.

The Strategic National Stockpile (SNS) currently contains three smallpox vaccines:

**ACAM2000****(Smallpox [Vaccinia] Vaccine, Live)** is a replication-competent vaccinia virus vaccine, indicated for active immunization against smallpox disease in persons determined to be at high risk for smallpox infection.*****Also see ACAM2000 (Smallpox Vaccine) Questions and Answers*
	**Jynneos Smallpox and Monkeypox Vaccine, Live, Non-Replicating** was approved on September 24, 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. Jynneos will be available for those determined to be at high risk of either smallpox or monkeypox infection. *For more information, see: FDA approves first live, non-replicating vaccine to prevent smallpox and monkeypox*
	**Aventis Pasteur Smallpox Vaccine****(APSV)**is an investigational, replication-competent vaccinia virus vaccine. In a smallpox emergency, APSV could potentially be made available under an IND or EUA for use in circumstances where approved vaccines are depleted or not readily available.Replication-competent vaccinia virus vaccines are generally safe and effective, but some people do experience side effects and adverse reactions. Severe adverse reactions are more common in people who are being vaccinated for the first time and among young children (≤5 years of age). Vaccinia Immune Globulin Intravenous (Human) (VIGIV) is indicated for the treatment and/or modification of certain conditions that are complications resulting from smallpox vaccination with replication-competent vaccinia virus vaccines.

*Also see**related information about smallpox vaccines**, from FDA’s Center for Biologics Evaluation and Research (CBER), and**Smallpox Vaccines**and**Medical Management of Adverse Reactions* *(information for clinicians) from CDC**.*

Therapeutics

There are two FDA-approved drugs for the treatment of smallpox.

**TPOXX (tecovirimat)** is indicated for the treatment of smallpox. TPOXX was the first approved smallpox therapeutic in the United States, approved July 13, 2018. On May 18, 2022, FDA approved an intravenous (IV) formulation of TPOXX to treat smallpox. The IV formulation (PDF, 565 KB)  is an option for those who are unable to swallow the oral capsule. *Also see: Drug Trial Snapshot: TPOXX*
	**Tembexa (brincidofovir)******- FDA approved Tembexa (brincidofovir) to treat smallpox on June 4, 2021.The Strategic National Stockpile (SNS) currently contains two smallpox therapeutics:

**TPOXX (tecovirimat)** is indicated for the treatment of smallpox. *Also see: Expiration Dating Extension: Mpox and Smallpox Therapeutics.*
	**Cidofovir** is an investigational therapeutic for the treatment of smallpox. Cidofovir has not been tested in people with smallpox, and thus it is not known whether a person with smallpox would benefit from treatment with Cidofovir. In a smallpox emergency, Cidofovir could potentially be made available under an IND or EUA for the treatment of smallpox if the circumstances warrant.*Also see Medical Management of Adverse Reactions from CDC, which includes information for clinicians on how to obtain VIGIV and antivirals.*

Diagnostics

Diagnosis of initial cases of smallpox in a smallpox emergency would likely be based on clinical diagnosis confirmed by follow-up laboratory testing. Laboratory diagnostic testing for Variola virus would occur in a CDC Laboratory Response Network (LRN) laboratory using specialized diagnostic tests and protocols for Variola virus.

Cleared Variola virus diagnostic tests:

Variola Virus Real-time PCR Assay, cleared for the qualitative detection of Variola virus DNA.Guidance for industry

Guidance for Industry: Smallpox (Variola Virus) Infection: Developing Drugs for Treatment or Prevention (PDF, 127 KB) (November 2019) - To assist sponsors in the clinical development of drugs for treatment or prevention of smallpox (variola virus) infection
	Guidance for Industry: Eligibility Determination for Donors of Human Cells, Tissues, and Cellular and Tissue-Based Products (HCT/Ps)(PDF, 502 KB) (August 2007) – *see Vaccinia*, *page 6*
	Guidance for Industry: Recommendations for Deferral of Donors and Quarantine and Retrieval of Blood and Blood Products in Recent Recipients of Smallpox Vaccine (Vaccinia Virus) and Certain Contacts of Smallpox Vaccine Recipients (December 2002)****Advisory Committee meetings

May 1, 2018 [ARCHIVED]: The Antimicrobial Drugs Advisory Committee met to discuss the new drug application (NDA) 208627 for TPOXX (tecovirimat), sponsored by SIGA Technologies Inc., for the proposed indication of the treatment of smallpox disease caused by Variola virus in adults and pediatric patients. Meeting materials, including briefing information and minutes are available.Consumer protection

Unfortunately, during outbreak situations, fraudulent products claiming to prevent, treat or cure a disease almost always appear. The FDA monitors for fraudulent products and false product claims related to smallpox and takes appropriate action to protect consumers.

Fraudulent product updates and warning letters

FDA acts to remove unproven, potentially harmful treatment used in ‘stem cell’ centers targeting vulnerable patients - Vaccinia Virus Vaccine (Live) seized after being used inappropriately in vulnerable cancer patients (August 28, 2017)News and statements

**February 22, 2023:**On February 3, 2023, FDA approved a shelf-life extension of TPOXX (tecovirimat) Injection, 200 mg, from 24 months to 42 months for some lots of TPOXX injection. TPOXX supplied by the Strategic National Stockpile (SNS) does not have an expiration date printed on its label. To determine the expiration date for product received from the SNS, find the lot number on the product label and refer to this table to identify the corresponding expiration date.
	**May 18, 2022:**FDA approved an intravenous (IV) formulation (PDF, 565 KB) of TPOXX (tecovirimat) to treat smallpox. The oral formulation of the drug was originally approved in 2018. The IV formulation is an option for those who are unable to swallow the oral capsule. *Also see**Therapeutics**below*
	**June 4, 2021:** FDA approves drug to treat smallpox - FDA approved Tembexa (brincidofovir) to treat smallpox. Although the World Health Organization declared smallpox, a contagious and sometimes fatal infectious disease, eradicated in 1980, there have been longstanding concerns that the virus that causes smallpox, the variola virus, could be used as a bioweapon.
	**November 15, 2019:**FDA In Brief: FDA issues final guidance for development of smallpox treatments as part of critical preparedness efforts - FDA issued final guidance, Smallpox (Variola Virus) Infection: Developing Drugs for Treatment or Prevention (PDF, 127 KB), which is designed to assist drug manufacturers designing studies to appropriately establish the safety and efficacy of drugs to treat or prevent smallpox infection. *Also see* *Guidance for industry*below
	**September 24, 2019:**FDA announcedthe approval of Jynneos Smallpox and Monkeypox Vaccine, Live, Non-Replicating, 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. Jynneos will be available for those determined to be at high risk of either smallpox or monkeypox infection. This vaccine is also part of the Strategic National Stockpile(SNS), the nation’s largest supply of potentially life-saving pharmaceuticals and medical supplies for use in a public health emergency that is severe enough to cause local supplies to be depleted. The availability of this vaccine in the SNS will help ensure that the vaccine is accessible in the U.S. if needed.Additional resources

Smallpox information from CDC (includes information for clinicians, laboratory personnel, public health planners, and vaccinators)
	Smallpox information from the National Institutes of Health
	Smallpox information from the World Health Organization
	FDA Monkeypox Response
	About Emergency Use Authorization
	Animal Rule information
	The FDA's Drug Review Process: Ensuring Drugs Are Safe and EffectiveContact FDA

Consumers and general information: contact FDA
You may also call 1-888-INFO-FDA / (1-888-463-6332)

Report a fraudulent smallpox product
Includes options for phone and online reporting

Press: contact the Office of Media Affairs
Email fdaoma@fda.hhs.gov or call 301-796-4540

Contact FDA’s Medical Countermeasures Initiative (MCMi)AskMCMi@fda.hhs.gov

                                                                                  Content current as of:
      05/03/2023
              
              
Topic(s)
			  Emergencies
				    				       				    				       BiologicalMCM Issues

          
                        Advanced Manufacturing
          Antimicrobial Resistance Information from FDA
          Ebola Preparedness and Response Updates from FDA
          FDA/DoD Collaborations
          FDA Mpox Response
          Medical Countermeasure Monitoring and Assessment
          Pediatric Medical Countermeasures
          Preparedness Information for Consumers
          Radiological and Nuclear Emergency Preparedness Information from FDA
          Smallpox Preparedness and Response Updates from FDA
          Zika Virus Response Updates from FDA
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