Key Messages:
Many patients with mpox have a mild, self-limited disease and recover without medical intervention. However, the prognosis for mpox depends on multiple factors, including immune status, previous vaccination, co-morbid conditions, and initial health status.
Supportive Care should be initiated for all patients who have mpox symptoms. This may include topical or systemic medications and/or other clinical interventions to
control pain, itching, nausea and vomiting. Patients should be monitored closely to ensure resolution of illness without complications that would require further intervention. Patients with confirmed or suspected mpox should also be screened for human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs), including syphilis, gonorrhea, and chlamydia. The CDC has reported that approximately 40% of mpox cases had HIV or another STI in the past year (CDC).
There is no treatment approved specifically for mpox infections, however tecovirimat (also known as TPOXX) is typically the first therapeutic that is considered if patients with mpox require more than supportive care. Tecovirimat is an FDA-approved antiviral medication for the treatment of human smallpox disease in adults and children, based on animal efficacy data and safety data in adults. As tecovirimat is not FDA-approved for use in mpox, it is only available through specific channels.
Enrollment in
Study of Tecovirimat for Mpox (STOMP) Clinical Trial has closed and oral tecovirimat is no longer available via the STOMP trial. Initial analysis of data from two NIH-sponsored randomized clinical studies designed to assess the efficacy and safety of a 14-day course of tecovirimat in treating human mpox,
PALM007 and
STOMP, became available in August and December 2024, respectively.
- These studies showed that tecovirimat was safe but did not reduce the time to resolution of mpox lesions in participants who received tecovirimat compared to those who received placebo.
- PALM007 study participants were adults and children with clade I mpox in the Democratic Republic of the Congo.
- STOMP study was conducted in the U.S. and a few other countries with clade IIb mpox outbreaks; participants randomized to tecovirimat or placebo arm were adults with clade IIb mpox who did not have severe immunocompromise or severe mpox and were not pregnant or lactating.
- The findings from these clinical trials suggest that most patients with mpox who do not have severe disease or risk factors for severe disease (e.g., severe immunocompromise) will recover with
supportive care, including
pain management.
- The role of tecovirimat in treatment of mpox in patients with severe immunocompromise, including advanced HIV, has not been determined and requires additional clinical trials.
Tecovirimat remains available in oral or IV form through the
CDC-held Expanded Access Investigational New Drug (EA-IND) protocol (PDF) for compassionate use for patients who meet eligibility criteria for protracted or life-threatening disease, or risk for protracted or life-threatening disease (see criteria below). The decision to treat is at the clinical discretion of the health care provider as long as the patient meets eligibility criteria. A positive lab result is not necessary to initiate treatment if there is high clinical suspicion. Tecovirimat from the Strategic National Stockpile remains available for treatment of mpox in patients who meet eligibility criteria under the
CDCās EA-IND protocol (PDF):
- Persons with severe immunocompromise (i.e., HIV with CD4 <200 or comparable severe immunocompromise).
- Persons with protracted or life-threatening manifestations of mpox as defined in the protocol.
- Persons with active skin conditions (e.g., atopic dermatitis, eczema, impetigo) that place them at higher risk of disseminated infection.
- āPregnant or lactating persons and children, regardless of disease severity or underlying comorbidities.
Providersāā or facilities providing or prescribing tecovirimat must review and comply by the
CDC-held EA-IND protocol (PDF), including eligibility criteria, and should ensure they are using the most up-to-date version of the protocol. ā
Health care providers prescribing under the
EA-IND Protocol (PDF) can obtain oral tecovirimat from the state stockpile, coordinated through your local health department (LHD). To request oral tecovirimat:
-
Providers can submit a completed request form to their LHD
Medical Health Operational Area Coordinator (MHOAC) who may source oral tecovirimat locally or will submit a resource request to the CDPH. Medications will be shipped to the healthcare facility.
-
Providers or facilities must review and comply by the eligibility criteria and follow the CDC requirements for use under the
EA-IND protocol (PDF), including submission of the required forms.
-
āWhenever a patient is initiated on tecovirimat, health care providers are asked to inform the LHD corresponding to the patientās residence. This is so that: (1) treatment information can be accurately reported in the state surveillance system (CalREDIE) and (2) local medication supplies can be monitored.
Pre-positioning supply: The
CDC EA-IND protocolā (PDF) allows the use of pre-positioned tecovirimat to treat mpox during an outbreak for patients who meet eligibility criteria. Any remaining tecovirimat from previously deployed supply still within
expiry can be used for
EA-IND eligible patients (PDF).
II. Requesting IV Tecovirimat (TPOXX)ā
IV tecovirimat remains available for use in mpox patients that require an IV formulation (i.e., those who are unable to take oral therapy or for whom there is a concern that oral absorption may be altered).
All supply requests for IV tecovirimat for immediate patient use under the CDC EA-IND Protocol (PDF) should be sent directly to the CDC. To request IV tecovirimat for immediate patient use:
- Contact the CDC by calling the CDC Emergency Operations Center at (770) 488-7100 (including off-hours), or emailing
poxvirus@cdc.gov and
mpxtreatment@cdph.ca.gov (during business hours) to reach the CDC and CDPH Clinical Consultation Teams. If it is determined during the case consultation that CDC is unable to fulfill the request within 24 hours, a temporary stopgap with state supply of IV tecovirimat (limited) via the LHD
MHOAC may be coordinated.
- Providers or facilities must review and comply by the eligibility criteria and follow the CDC requirements for use under the
EA-IND protocol (PDF), including submission of the required forms.
- āWhenever a patient is initiated on tecovirimat, health care providers are asked to
inform the LHD corresponding to the patientās residence. This is so that: (1) treatment information can be accurately reported in the state surveillance system (CalREDIE) and (2) local medication supplies can be monitored.
Pre-positioning supply: The US Department of Health and Human Services (HHS) no longer allows pre-positioning of IV tecovirimat but facilities may still have inventory available. There was a product shelf-life extenāsion released for IV tecovirimat and lot numbers and expiration dates for remaining tecovirimat is found on HHS
SNS Products: Vaccines and Treatment Available for Use in the Mpox Response.
III. Tecovirimat (TPOXX) Reporting
The federal government requires tecovirimat inventory reporting. Providers/facilities should report their inventory through the US Department of Health and Human Services enhanced Health Partner Order Portal (HPOP) weekly and at the time of resource requests. HPOP is used to report and track tecovirimat inventory. For questions on HPOP use, contact
hpop.support@hhs.govā or (833) 868-6386 (5AM ā 2PM PST).
āāWhen tecovirimat is prescribed orally via the CDCās EA-IND protocol, patients should be advised to take tecovirimat with fatty meals to ensure adequate gastrointestinal absorption and to maximize serum levels of the drug. Inadequate serum levels could promote resistance. Dosage and administration of tecovirimat guidance for adults and children is provided in the
CDC EA-IND protocol (PDF).
Treatment considerations for those with or at risk for protracted or life-threatening disease include the following:
- The standard tecovirimat treatment course is 14 days. If needed, tecovirimat treatment can be extended beyond the standard 14-day course on a short-term basis (e.g., an additional 3-7 day course, with close monitoring for safety and clinical response).
- Certain patients with severe mpox or at high risk for severe mpox (e.g., patients with HIV and CD4 count <200 cell/mm3 or other severely immunocompromising conditions) should be considered for concurrent administration of other therapeutics, including cidofovir, brincidofovir, and vaccinia immune globulin IV (VIGIV). Consultation with CDC, infectious disease specialists, and other experts for any patient who may benefit from receiving multiple therapeutics is encouraged.
- āFor immunocompromised patients, make all efforts to minimize immune suppression to the extent possible (e.g., ensure persons with HIV are receiving effective antiretroviral therapy) and limit the use of immunosuppressive therapies (e.g., chemotherapy, TNF inhibitors), if feasible.
Additional medical countermeasures currently available from the Strategic National Stockpile as
options for the treatment of mpox include brincidofovir and vaccinia immune globulin. Cidofovir is also available commercially. These additional antivirals are typically used in conjunction with tecovirimat for severe or refractory cases. For more information, see CDC MMWR on
Treatment Considerations for Severe Manifestations of Mpox and
CDC Clinical Treatment of Mpox for details on how to access additional therapeutics.
Clinicians should be aware of the concern for
development of TPOXX resistance, especially in patients who are immunocompromised or have severe disease and require prolonged TPOXX treatment.
CDC scientists are actively monitoring for changes in the mpox virus that could make the virus less susceptible to tecovirimat. Because of the potential for the virus to become resistant to tecovirimat, it is important the drug be used in a judicious manner. āMore information about tecovirimat resistance can be found below, and on the
FDA and the
CDC websites.
Tecovirimat resistance testing considerations:
- āāIn patients with persistent or progressive mpox after completing 14 days of tecovirimat, consider testing
lesion swab samples (PDF) for possible resistance to tecovirimat and performing
plasma pharmacokineticsāāā (PDF), for public health surveillance purposes.
- Ideally, resistance and pharmacokinetic testing should be performed concurrently to determine if any cases of confirmed resistance are associated with drug levels below target concentrations.
- Collection āof lesion sampāāāles for the purpose of whole genome sequencing with testing for resistance-associated mutations will help monitor for the potential emergence of antiviral resistance. However, individual patient results cannot be made available for directly informing individual patient treatment decisions at this time.
Please contact your LHD, CDPH, and the CDC to discuss any concerns about tecovirimat resistance, any cases requiring prolonged tecovirimat courses, or any situations in which advanced therapeutics is being considered.āāā