Jaxteran (Dimethyl Fumarate)

Dimethyl fumarate is employed in immune‑mediated conditions, targeting disease activity in both the central nervous system and the skin, thereby modifying relapse rates and lesion development.

• Relapsing multiple sclerosis: reduces the frequency of clinical relapses and may slow accumulation of disability.
• Moderate-to-severe plaque psoriasis: improves skin lesion clearance and decreases disease severity scores.

• Dimethyl fumarate activates the nuclear factor erythroid 2‑related factor 2 (Nrf2) transcription pathway. By modifying cysteine residues on Keap1, it releases Nrf2, allowing translocation into the nucleus where antioxidant response element genes are up‑regulated. This enhances cellular antioxidant capacity, reduces oxidative stress, and modulates pro‑inflammatory cytokine production, providing anti‑inflammatory and neuroprotective effects relevant to multiple sclerosis and psoriasis.

Dimethyl fumarate is associated with a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Flushing: transient warmth and redness, often occurring after the first doses.
• Gastrointestinal discomfort: nausea, abdominal pain, or diarrhoea.
• Upper respiratory tract symptoms: nasopharyngitis or sore throat.
• Decreased lymphocyte count: mild reductions observed in routine blood tests.

Serious or Rare Side Effects

• Progressive multifocal leukoencephalopathy (PML): rare opportunistic brain infection.
• Severe hypersensitivity reactions: including Stevens‑Johnson syndrome or toxic epidermal necrolysis.

When prescribing dimethyl fumarate, clinicians should consider several precautionary measures to minimize risk.

• Baseline monitoring: obtain complete blood count and liver function tests before initiating therapy.
• Infection risk: assess for active infections and avoid use in patients with known immunosuppression.
• Pregnancy: avoid use during pregnancy unless potential benefit justifies risk, as safety data are limited.
• Vaccination: administer necessary vaccines prior to treatment initiation.
• Renal or hepatic impairment: use with caution and monitor organ function regularly.
• Store at ambient temperature: keep below 25 °C, retain in original packaging, and protect from moisture.

Dimethyl fumarate may interact with other medicines, affecting its efficacy or safety profile.

Major Interactions (Avoid)

• Live vaccines: concurrent use can increase risk of vaccine‑derived infection.
• Immunosuppressants: combined therapy may heighten infection risk.

Moderate Interactions (Monitor Closely)

• Antioxidant supplements (e.g., vitamin C, E): may attenuate Nrf2 activation.
• CYP450 substrates: dimethyl fumarate can modestly influence metabolism of drugs processed by CYP enzymes.
• Anticoagulants: monitor for altered bleeding risk due to potential platelet effects.