Cobimetinib requires vigilant monitoring for multiple organ toxicities and drug interactions.

Critical Monitoring and Contraindication

Key precautions include:

New malignancies: Monitor for cutaneous (e.g., SCC, BCC) and non-cutaneous cancers pre-treatment, every 2 months during therapy, and for 6 months post-treatment.

Cardiomyopathy: Assess LVEF via echocardiography/MUGA at baseline, 1 month post-initiation, then every 3 months.

Hemorrhage: Grade 3 events warrant withholding; Grade 4 mandates permanent discontinuation.

Ocular toxicity: Regular ophthalmologic exams for retinopathy/retinal vein occlusion.

Hepatotoxicity/Rhabdomyolysis: Monitor liver enzymes (ALT/AST) and CPK periodically.

Photosensitivity: Advise sun avoidance and protective measures.

Embryo-fetal risk: Contraception is required during and 2 weeks post-treatment. Drug interactions with CYP3A modulators are strictly managed.