The present invention relates to a method for determining the
efficacy of a
drug treatment for a subject suffering from malignant
melanoma, wherein said method comprises the steps of: (i) evaluation of the presence or absence of a
genetic alteration in a BRAF
gene, a. detecting the presence and / or quantity of at least one biomarker in a biological sample obtained from said subject, wherein said biomarker is BRAF V600
mutated protein and / or at least one immunoproteasome
protein, and b. classifying the subject as having a high or low likelihood of responding to a
drug treatment, based on the presence and / or quantity of said at least one biomarker, wherein in case the
genetic alteration in the BRAF
gene is present, the presence and / or quantity of at least one BRAF V600
mutated protein and at least one immunoproteasome
protein is detected in said biological sample, and wherein in case the
genetic alteration in the BRAF
gene is not present, the presence and / or quantity of at least one immunoproteasome
protein is detected in said biological sample.