Results from a study suggest that an intermittent treatment regimen might prevent drug-resistance in patients with melanoma. Vemurafenib-resistant tumours in mice and humans where shown to be dependent on the drug to grow. In 14 out of 19 patients with vemurafenib-resistant tumours, tumour growth decreased after treatment cessation. In animal models, drug resistance was prevented by intermittent dosing. Taken together, these data indicate that intermittent treatment might prevent vemurafenib resistance.