Aims: Lenvatinib is an oral multi-kinase inhibitor approved for the treatment of adults with progressive, locally advanced or metastatic, differentiated thyroid carcinoma refractory to radioactive iodine.
Materials and methods: A literature review was undertaken to inform the development of consensus-based guidance for the routine management of adverse events associated with lenvatinib. PubMed was searched on 24 October 2017; the search terms were 'lenvatinib' and 'thyroid cancer'.
Results: Hypertension, diarrhoea, weight loss, skin toxicities and cardiovascular adverse events were considered. For grade 1/2 diarrhoea, initial treatment should be loperamide with a 1-week treatment interruption if diarrhoea persists and dose reduction if diarrhoea recurs on reinitiation of lenvatinib. Blood pressure should be monitored daily in patients with pre-existing hypertension, otherwise from 1 week after the initiation of lenvatinib and weekly for the first 2 months. For patients with systolic blood pressure ≥135 mmHg to <160 mmHg or diastolic blood pressure ≥85 mmHg to <100 mmHg, lenvatinib should be continued but antihypertensive therapy initiated/intensified. For patients who remain hypertensive, a treatment break can be considered with lenvatinib reinitiated at a reduced dose once the patient's blood pressure has stabilised for at least 48 h. Weight loss of 10% of baseline body weight or the onset of anorexia should be managed with a 1-week treatment break; patients should maintain a healthy, active lifestyle. For patients with grade 2 proteinuria, lenvatinib may be continued, but an angiotensin II receptor blocker or angiotensin converting enzyme inhibitor should be commenced. For grade >3 proteinuria, lenvatinib should be interrupted until proteinuria returns to 1+. For chronic proteinuria, lenvatinib should be stopped. Skin toxicities should be managed with moisturisers or emollients and soap substitutes.
Conclusions: Prophylaxis, regular monitoring and symptomatic management with appropriate short treatment breaks and, for persistent adverse events, dose reductions, are recommended to enable patients to remain on the optimal dose regimen.