Skip to content
ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
MEK inhibitor

Cobimetinib (Specialist drug)

Brand names: Cotellic

Cobimetinib is an oral MEK inhibitor used, in combination with the BRAF inhibitor vemurafenib, for unresectable or metastatic melanoma harbouring a BRAF V600 mutation.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It selectively inhibits MEK1/MEK2 within the MAPK (RAS-RAF-MEK-ERK) signalling pathway, blocking downstream ERK activation and tumour cell proliferation.

Prescribing in practice

  • Can cause serious cardiotoxicity (reduced left ventricular ejection fraction), serous retinopathy/visual disturbance, hepatotoxicity, rhabdomyolysis and severe photosensitivity, requiring baseline and periodic assessment.
  • It is a CYP3A4 substrate, so concomitant strong CYP3A inhibitors or inducers should be avoided.
  • Prescribed only by specialists with experience in oncology and anticancer therapy, in combination with vemurafenib per the SPC.

Monitoring

Monitor left ventricular ejection fraction by echocardiography, liver function and creatine kinase, and arrange ophthalmological assessment if visual symptoms occur.

Counselling the patient

  • Use broad-spectrum sun protection and protective clothing as severe sunburn can occur.
  • Report changes in vision, breathlessness, muscle pain or dark urine promptly.
  • Effective contraception is advised during treatment.

Evidence & guidelines

Efficacy in BRAF V600-mutant melanoma was established in the coBRIM trial and is reflected in the SPC and NICE guidance.

Reference: Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Drugs
Pathways