Ibrexafungerp, known by its brand name Brexafemme, is a prescription medication used to treat fungal infections. Approved in the United States in 2021, it belongs to a new class of drugs called triterpenoids. This offers a novel approach to combating certain fungal pathogens.
Approved Medical Uses
Ibrexafungerp is approved to treat vulvovaginal candidiasis (VVC), commonly known as a vaginal yeast infection. This condition, caused by an overgrowth of Candida fungi, leads to symptoms like itching, burning, and unusual vaginal discharge. The medication resolves active VVC infections in adult and post-menarcheal adolescent females. It also helps reduce the incidence of recurrent VVC, preventing future episodes in individuals prone to them.
Unique Mechanism of Action
Ibrexafungerp works by targeting a specific component of the fungal cell, offering a distinct way to fight infection. It functions by inhibiting an enzyme called β-1,3-D glucan synthase. This enzyme is responsible for building a strong and protective cell wall around the fungus. Imagine glucan synthase as the primary bricklayer constructing the walls of a house.
By stopping these “bricklayers,” ibrexafungerp prevents the fungus from properly constructing or repairing its cell wall. This disruption weakens the fungal cell wall, making it unstable and leading to the eventual death of the fungal cell. This fungicidal action differs from some other antifungal classes, such as azoles (like fluconazole), which primarily target the fungal cell membrane rather than its wall. This difference in mechanism provides an important alternative treatment option, especially for fungal strains that may have developed resistance to other types of antifungals.
Administration and Dosing
Ibrexafungerp is an oral tablet, available in a 150 mg strength. For treating an active vulvovaginal candidiasis infection, the typical dosage involves taking 300 mg (two 150 mg tablets) twice in a single day, approximately 12 hours apart. The medication can be taken with or without food.
When used to reduce the risk of recurrent vulvovaginal candidiasis, the dosing regimen changes. Patients will take the same two-dose, one-day course (300 mg twice daily) once a month. This monthly treatment is typically continued for a period of six months.
Safety Profile and Warnings
Like all medications, ibrexafungerp can cause side effects, though generally mild to moderate in severity. The most frequently reported adverse reactions include diarrhea, nausea, abdominal pain, and dizziness. Other less common side effects can include vomiting, headache, and tiredness. Most individuals tolerate the treatment well, with few discontinuing due to side effects.
A significant warning concerns ibrexafungerp’s use during pregnancy. The medication carries a boxed warning, indicating it is contraindicated for individuals who are pregnant or may become pregnant. Studies have shown that ibrexafungerp can cause fetal abnormalities in animals. There is a high risk that taking ibrexafungerp during pregnancy could lead to pregnancy loss, premature birth, fetal death, or birth defects. Therefore, individuals who can become pregnant are advised to take a pregnancy test before starting each course of treatment. It is also recommended to use effective birth control methods during treatment and and for at least four days after the last dose. For those undergoing the monthly regimen for recurrent VVC prevention, contraception should be used throughout the entire six-month treatment period and for four days following the final dose.