Figure 6.

Single-cycle anti-HER2-DOTA-PRIT with IA of 55.5 MBq leads to CRs in mice with small-sized BT-474 tumors, but is generally ineffective in mice bearing medium-sized BT-474 tumors. Tumor volumes are presented as mean ± SEM. Black arrow indicates the day of ¹⁷⁷Lu-DOTA-Bn injection. Survival was defined as time to tumor doubling and included deaths from other causes. (A) Treatment of mice bearing small-sized tumors with single-cycle anti-HER2-DOTA-PRIT + 55.5 MBq of ¹⁷⁷Lu-DOTA-Bn versus control groups. Median survival was 7 d for no treatment, 16 d for BsAb, 7 d for 55.5 MBq of ¹⁷⁷Lu-DOTA-Bn only, and undefined for anti-HER2-DOTA-PRIT + 55.5 MBq of ¹⁷⁷Lu-DOTA-Bn. (B) Treatment of mice bearing medium-sized tumors with single-cycle anti-HER2-DOTA-PRIT + 11.1, 33.3, or 55.5 MBq of ¹⁷⁷Lu-DOTA-Bn versus control groups. Median survival was 6 d for no treatment, 25 d for 33.3 MBq of ¹⁷⁷Lu-DOTA-Bn only, 21 d for anti-HER2-DOTA-PRIT + 11.1 MBq of ¹⁷⁷Lu-DOTA-Bn, 42 d for anti-HER2-DOTA-PRIT + 33.3 MBq of ¹⁷⁷Lu-DOTA-Bn, and 108 d for anti-HER2-DOTA-PRIT + 55.5 MBq of ¹⁷⁷Lu-DOTA-Bn.