Atlanta—Thousands of cases of monkeypox have been diagnosed in the United States, and infection with the orthopoxvirus has made some patients very sick while proving to be quite painful in some cases.

One issue is the difficulty for patients to obtain medications that can help with the infection. Tecovirimat (also known as TPOXX or ST-246) is approved by the FDA for the treatment of human smallpox disease caused by Variola virus in adults and children. However, its use for other orthopoxvirus infections, including monkeypox, is not approved by the FDA. The CDC maintains a nonresearched expanded access Investigational New Drug (EA-IND) protocol, however, that allows for the use of tecovirimat for primary or early empiric treatment of nonvariola orthopoxvirus infections, including monkeypox, in adults and children of all ages.

The challenge for care facility pharmacists and other clinicians is getting their hands on it. TPOXX is available through the Strategic National Stockpile. To request TPOXX, clinicians and care facility pharmacists can contact their state/territorial health department or the CDC (Emergency Operations Center: 770-488-7100; Poxvirus@cdc.gov).

Once received, treatment with TPOXX can begin immediately after obtaining informed consent. No preregistration is required for clinicians or facilities, according to the guidance.

Additional forms requested under the EA-IND can be returned to the CDC after treatment begins.

Public health officials advise that tecovirimat may be considered for treatment in people infected with monkeypox virus who have severe disease, defined as hemorrhagic disease, confluent lesions, sepsis, encephalitis, or other conditions requiring hospitalization.

It also can be prescribed to those at high risk of severe disease. That includes people with:

• Immunocompromising conditions (e.g., HIV/AIDS, leukemia, lymphoma, generalized malignancy, solid organ transplantation, therapy with alkylating agents, antimetabolites, radiation, tumor necrosis factor inhibitors, high-dose corticosteroids, being a recipient with hematopoietic stem cell transplant <24 months posttransplant or >24 months but with graft-versus-host disease or disease relapse, or having autoimmune disease with immunodeficiency as a clinical component).

• A history or presence of atopic dermatitis, people with other active exfoliative skin conditions (e.g., eczema, burns, impetigo, varicella zoster virus infection, herpes simplex virus infection, severe acne, severe diaper dermatitis with extensive areas of denuded skin, psoriasis, or Darier disease [keratosis follicularis]).

• One or more complication (e.g., secondary bacterial skin infection; gastroenteritis with severe nausea/vomiting, diarrhea, or dehydration; bronchopneumonia; concurrent disease or other comorbidities).

• With aberrant infections involving accidental implantation in eyes, mouth, or other anatomic areas where Monkeypox virus infection might constitute a special hazard (e.g., the genitals or anus).

Pediatric populations are also eligible to receive the drug, particularly patients aged younger than 8 years, as well as pregnant or breastfeeding women.

The guidance noted that tecovirimat is available as an oral capsule (200 mg) and injection for IV administration. Drug absorption of oral formulation is dependent on adequate concurrent intake of a full, fatty meal.

The CDC cautions that IV tecovirimat should not be administered to patients with severe renal impairment (creatinine clearance [CrCl] <30mL/min), adding, "Oral formulation remains an option for this population. IV tecovirimat should be used with caution in patients with moderate (CrCl 30-49 mL/min) or mild (CrCl 50-80 mL/min) renal impairment as well as pediatric patients <2 years of age given immature renal tubular function."

The most common adverse reactions include infusion-site pain and related issues, headache, and nausea.

"Significant interactions have been reported in healthy adults with coadministration of repaglinide (hypoglycemia) and midazolam (decreased effectiveness of midazolam)," the announcement pointed out.

Pharmacists should be aware that the drug is provided at no cost.

The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.