MedeliX
Start asking

momelotinib

Omjjara · ATC code 6453

Key facts
Active substance
momelotinib
ATC code
6453
Authorisation
centrally authorised across the EU (EMA)
Dosage forms
Omjjara 100 mg film-coated tablets / Omjjara 150 mg film-coated tablets / Omjjara 200 mg film-coated tablets
Marketing authorisation holder
GlaxoSmithKline Trading Services Limited
Information as of
2026-10-29

Key facts

Momelotinib (Omjjara, film-coated tablets) is a Janus kinase (JAK) inhibitor. It is used for myelofibrosis with splenomegaly or symptoms in patients with moderate to severe anaemia.

What it is used for

  • Adults with primary myelofibrosis, post polycythaemia vera or post essential thrombocythaemia myelofibrosis with disease-related splenomegaly or symptoms and moderate to severe anaemia.
  • For JAK inhibitor-naïve patients or those previously treated with ruxolitinib.

Dosing

  • Recommended dose: 200 mg once daily; not to be combined with other JAK inhibitors.
  • Complete blood count and liver tests before starting, periodically during treatment and as clinically indicated.
  • Thrombocytopenia, neutropenia, hepatotoxicity or other toxicities: interruption or reduction by 50 mg steps; details in the full text.
  • Severe hepatic impairment (Child-Pugh C): starting dose 150 mg once daily; no adjustment for mild or moderate impairment.

Contraindications

  • Hypersensitivity to the active substance or any of the excipients.
  • Pregnancy and breast-feeding.

Important warnings

  • Serious and fatal bacterial and viral infections; do not start in patients with active infections.
  • Hepatitis B reactivation can occur; treat and monitor chronic HBV according to guidelines.
  • New severe thrombocytopenia and neutropenia; check blood counts regularly.
  • Major adverse cardiovascular events (MACE) and thrombosis have been reported with JAK inhibitors.

Side effects

  • Very common: diarrhoea (23%), thrombocytopenia (21%), nausea (17%), headache, dizziness, fatigue, asthenia, abdominal pain, cough.
  • Most common severe reaction (≥ Grade 3): thrombocytopenia (12%).

Interactions

  • Strong CYP3A4 inducers (e.g. rifampicin, carbamazepine, phenytoin, St John's wort) may reduce exposure; monitor myelofibrosis symptoms more closely.
  • OATP1B1/1B3 inhibitors (e.g. ciclosporin) may increase exposure.
  • Momelotinib inhibits BCRP and increased rosuvastatin exposure; monitor for adverse reactions of BCRP substrates.

Pregnancy and breastfeeding

  • Contraindicated during pregnancy and breast-feeding.
  • Women using systemic hormonal contraception should add a barrier method during treatment and for at least 1 week after.

Summary of the official product information, written with AI on 2026-10-29. Every number was checked automatically against the original text. Not reviewed by a physician – the full official text is authoritative.

Full official text →

Common questions – ask Medelix

For patients

Package leaflet, verbatim

This product has no separate US patient information.

Authorisation and brand names by country

Medicines with exactly this active-substance composition, as listed in the national registers – alphabetical and without ranking. Whether a product is currently available is not shown here.

EU – centrally authorised (all member states)

  • OmjjaraGlaxoSmithKline Trading Services Limited · EMEA/H/C/005768

Source: European Medicines Agency (EMA), product information

Brand names in 3 more European countries
Iceland
Omjjara
Liechtenstein
Omjjara
Norway
Omjjara

EMA – Article 57 product data (EU/EEA), 2026-10-29

Medelix receives no money from pharmaceutical companies. Brand names are listed alphabetically and without ranking.

Another question about this substance?

Medelix answers clinical questions from guidelines, studies and product information – every claim with its source.

Sources

  1. European Medicines Agency. Omjjara – EPAR, Product Information. 2026-10-29. https://www.ema.europa.eu/en/documents/product-information/omjjara-epar-product-information_en.pdf

Editorial: Medelix editorial team · last updated 2026-10-29 · How these pages are made · Report an error

Source: European Medicines Agency (EMA), product information. Not advertising, not a treatment recommendation. For questions about your own treatment, ask your doctor or pharmacist.