The mortality of larvae and pupae of Adoxophyes orana was examined by keeping larvae of each larval instar (L1–L5) on an artificial diet in laboratory conditions. Larvae were infected by using an artificial diet containing AdorGV-based CAPEX® 2. Samples of uninfected larvae from each instar served as controls. The mortality of larvae infected in the 1^st instar was 100%, compared to a mortality of 68% in the control. In both, the larvae died before the 5^th larval instar. With larvae infected in subsequent instars the mortality rate declined gradually (96%–72%–40%–12%) and death occurred predominantly in the 5^th larval instar. The mortality of larvae in the controls was low (12%–12%–0%–0%). The mortality of pupae from larvae infected in the 2^nd, 3^rd and 4^th instar was high (100%–86%–93%), and the mortality of larvae and pupae combined was close to 100%. Mortality of pupae developed from larvae infected in the 5^th instar was 27% and that of larvae and pupae combined was 36%. The mortality of pupae developed from uninfected larvae in all controls was low (max. 8%). These results demonstrated the high efficacy of AdorGV to cause high mortality of larvae and pupae of Adoxophyes orana in laboratory conditions.