While the BRAF V600E cell line (A-375) was sensitive to all three inhibitors, the ΔNVTAP cell lines showed high sensitivity toward GDC-0879 and AZ-628, but complete resistance to vemurafenib (Figure 3A ) after 1 hr treatment. In cell viability assays (72 hr), a panel of BRAF V600E cell lines exhibited similar sensitivity toward all three inhibitors (Figure 3B), while the ΔNVTAP lines were resistant to vemurafenib, partially sensitive to GDC-0879, and sensitive to AZ-628.