Baloxavir marboxil

XOFLUZA

What it isProdrug of an influenza cap-dependent endonuclease inhibitor; uncomplicated influenza.

Why this oneA single oral administration completes treatment, unlike multiday neuraminidase-inhibitor regimens.

What limits itResistance can emerge during therapy, especially in children; polyvalent cations reduce absorption.

FDA-approved for

FDA dosing	Population	Start	Target	Max
Influenza — treatment or post-exposure prophylaxis	≥5 y, 20 to <80 kg	40 mg single dose	40 mg x1	40 mg once
Influenza — treatment or post-exposure prophylaxis	≥80 kg	80 mg single dose	80 mg x1	80 mg once
Influenza — treatment or post-exposure prophylaxis	Peds 15 to <20 kg (suspension packets)	30 mg single dose	30 mg x1	30 mg once
Influenza — treatment or post-exposure prophylaxis	Peds <20 kg (oral suspension bottle)	2 mg/kg single dose	2 mg/kg x1	weight-based

Renal Undefined

Hepatic Undefined

Single-dose regimen; not indicated in patients <5 years (treatment-emergent resistance)

Single dose; take within 48 h of symptom onset or exposure
May take with or without food
Avoid dairy, calcium-fortified beverages, antacids, laxatives, or polyvalent cation supplements (Ca, Fe, Mg, Se, Zn)

Pregnancy No adequate human data; no adverse developmental effects in animals

Lactation No human data; baloxavir present in rat milk

NO BOXED WARNINGS

Principal riskResistance emerges readily, especially in children

Cost, est. cash$300–$2,000/month

Generic entry2041 est.

Therapeutic safety burden2 / 4

Overdose danger2 / 4

Weight-gain liability0 / 4

Sedation liability0 / 4

QT / Torsades0 / 4

Direct muscarinic antagonism0 / 4

Embryofetal risk2 / 4

Legacy pregnancy categoryNot assigned — PLLR-era drug

Defining liabilityAgent-specific renal, hepatic, hematologic, metabolic and drug-interaction toxicity.

Box: minimal PK interactions