Diroximel fumarate

VUMERITY

What it isNRF2-activating prodrug of monomethyl fumarate; relapsing multiple sclerosis.

Why this oneEquivalent active-metabolite exposure causes less GI intolerance than dimethyl fumarate.

What limits itLymphopenia raises PML risk; monitor counts, and expect flushing despite the improved GI tolerability.

FDA-approved for

FDA dosing	Population	Start	Target	Max
Relapsing forms of multiple sclerosis	Adult	231 mg BID x7d	462 mg BID	462 mg BID

Titration After 7 days at starting dose, increase to maintenance.

Renal No adjustment for mild impairment; not recommended in moderate or severe impairment.

Hepatic Undefined

Swallow capsules whole; do not crush, chew, or sprinkle on food
If taken with food, avoid a high-fat/high-calorie meal (≤700 cal, ≤30 g fat); non-enteric aspirin 325 mg 30 min prior may reduce flushing
Avoid co-administration with alcohol
Temporary reduction to 231 mg BID if maintenance not tolerated; resume 462 mg BID within 4 weeks
Obtain CBC with lymphocyte count and LFTs before initiation

Pregnancy No adequate data; animal studies show embryofetal harm (skeletal abnormalities, mortality, reduced weight, neurobehavioral impairment).

Lactation No data on presence in human milk; effects on infant/milk unknown.

NO BOXED WARNINGS

Principal riskLymphopenia raising PML risk

Cost, est. cash$1,000–$15,000+/month

Generic entry2025

Therapeutic safety burden3 / 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 liabilitySerious infection, cytopenias, hepatic injury and malignancy risk require laboratory and clinical monitoring.