The combination of glofitamab with GemOx translates into strong antitumor efficacy and boosts intratumoral T-cell infiltration, activation, and proliferation. (A) In vivo efficacy study design. Humanized NSG mice with SC OCI-Ly18 tumors were randomized into 4 different experimental groups (14 per group) and were treated with either a vehicle (histidine buffer), SUD of glofitamab (0.15-0.5 mg/kg), GemOx (50/5 mg/kg), or a combination of glofitamab with GemOx, staggered in the first cycle and concomitant in the second using the same dosing as in monotherapy groups. Glofitamab treatments were administered IV and GemOx IP according to the displayed timeline. Five (7 in vehicle) animals per group were taken on day 29, and the study terminated on day 32. (B) Representative IHC staining for human CD19, CD20, and CD3 in untreated OCI-Ly18 tumors. (C) Average tumor volumes are presented as mean + SEM for all treatment groups over time. Tumor-free mice are indicated as x/9. (D) Tumor weights at the scout time point are found as mean + SEM values, with individual data points representing single mice. (E) Ex vivo flow cytometry analysis on tumors from scout animals reveals normalized CD4⁺ and CD8⁺ T-cell counts and CD8⁺ T-cell activation and exhaustion status (from left: Ki-67, granzyme B, PD1⁺/Tim3⁺ cells in percentage). (F) Spleen weights at the scout time point are found as mean + SEM values, with individual data points representing single mice. (G) Ex vivo flow cytometry analysis on spleen samples from scout animals reveals normalized CD4⁺ and CD8⁺ T-cell counts and CD8⁺ T-cell activation and exhaustion status (from left: Ki-67, granzyme B, and PD1⁺/Tim3⁺ cells in percentage). Bars represent means, and dots indicate individual mouse values. Statistical analysis was performed using 1-way ANOVA, and significant P values are indicated as follows: ∗P < .05; ∗∗P < .01; ∗∗∗P < .001; ∗∗∗∗P < .0001. IP, intraperitoneal.