– While waiting for study results, the CDC reviews clinical considerations.
The CDC has produced an interim report due to the lack of available clinical trial data for the treatment of severe mpox.
There are various FDA-regulated medications and biologics stocked for smallpox preparedness that can be used to treat severe mpox; however, there are many clinical considerations when employing these to manage strategic decision-making, according to the CDC report.
Medical countermeasures (MCMs) such as tecovirimat (Tpoxx), brincidofovir (Tembexa), cidofovir, trifluridine ophthalmic solution (Viroptic), and vaccinia immune globulin intravenous should be investigated for treatment of immunocompromised persons co-infected with HIV who have low CD4 levels (VIGIV).
Agam K. Rao, MD, of the CDC’s National Center for Emerging and Zoonotic Infectious Diseases, and colleagues noted in the interim guidance published in Morbidity and Mortality Weekly Report that syphilis, herpes simplex, varicella zoster, and molluscum contagiosum patients should also be examined.
The committee suggested, “Until results from controlled studies are available, these interim clinical considerations enable strategic decision-making about the use of MCMs to treat specific severe symptoms of mpox.”
The data in the paper was assembled from 250 U.S. mpox consultations provided by the CDC between May 2022 and January 2023, animal model research, expert comments, and reports on MCM use in a variety of orthopoxvirus cases.
“CDC’s approach to mpox cases was refined as more knowledge was learned through clinical consultations, many of which entailed repeated consultations and regular follow-up,” Rao’s group said. “The CDC advises doctors and health departments to explore these clinical treatment concerns while treating mumps patients.”
Although most people may recover from mumps with pain management, some with underlying illnesses require further help, the authors concluded.
Each therapy and treatment for mpox is covered in the study, along with indications for drug-drug interactions, past clinical instances, drug interaction and resistance information, precautions, and information on who may be the best candidate for each treatment.
For example, prolonged treatment with tecovirimat may result in drug resistance if safety signals and clinical response are not monitored. This antiviral should be taken with a fatty meal, according to the documentation. Individuals who are unable to take oral drugs due to gastrointestinal problems may not be able to absorb the medication, hence IV tecovirimat should be preferred for these patients.
The paper cautions that vaccination with live virus vaccines (such as varicella, measles, mumps, and rubella) should be postponed for three months when administering VIGIV. And for patients with ocular mpox affecting the cornea, “care should be exercised… because an animal investigation of vaccinia keratitis found that VIGIV was associated with chronic corneal scarring.” Trifluridine has been effective in treating ocular vaccinia virus infections in both animals and humans, however treatments lasting more than four weeks should be avoided due to the potential of corneal epithelial damage.
Those with a history of atopic dermatitis or eczema may also have uncontrolled viral transmission, “perhaps as a result of related abnormalities in the innate or adaptive immune response,” Rao and colleagues stated. Individuals with extensive breaks in the dermal barrier (e.g., burns, impetigo, varicella zoster virus infections, herpes simplex virus infections, severe acne, severe diaper dermatitis with extensive denuded skin, psoriasis, and Darier disease [keratosis follicularis]) may also be at risk for severe manifestations of uncontrolled viral spread.
Children, adolescents, and pregnant women should only take MCMs after assessing the potential advantages and risks, according to the authors of the report.
Moderately to severely immunocompromised individuals, such as those with advanced HIV or organ transplant recipients, have experienced diffuse and disseminated lesions affecting several organ systems, “perhaps due to prolonged viremia or uncontrolled viral proliferation,” Rao and colleagues stated. In these instances, “systemic sickness has resulted in death”
A recent global case analysis published in The Lancetopens in a new tab or window revealed that those with low CD4 counts are at an elevated risk for complications and mortality, with all deaths occurring in patients with CD4 levels 200 cells/mm3.
Patients with severe mpox symptoms have been observed to have hemorrhagic illness, confluent or necrotic lesions, severe necrotizing or obstructive lymphadenopathy, obstructive edoema, pulmonary nodules, encephalitis, myopericarditis, ocular infections, and sepsis. Immunocompromised patients are at a significant risk for these manifestations, even if they are not present at the initial healthcare visit.
“Optimal immune activity is necessary for recovery regardless of the number of MCMs delivered,” Rao and colleagues wrote, noting that antiviral MCMs may complement the immune response by inhibiting the reproduction, maturation, or transmission of the orthopox virus. “Unless a patient’s immune system is able to remove the virus, VIGIV may provide some amount of passive immunity to some individuals with moderate or severe immunosuppression. Yet, the early optimization of immune function (e.g., by temporarily postponing or reducing dosages of chemotherapy and immunomodulatory therapies and by swiftly commencing effective antiretroviral medicines [ARVs] for the treatment of HIV) is essential for positive outcomes.”
And regardless of immunological state, lesions on surfaces including the penile foreskin, urethral meatus, and vulva enhance their risk, Rao and colleagues observed. These conditions may predispose individuals to problems such as strictures and edoema, which may necessitate urethral catheterization, colostomy, or surgical debridement.