Figure 3.

Clinical activity of xaluritamig in evaluable patients. A, Best PSA percentage change from baseline. Asterisk indicates confirmed PSA responders, and dashed lines indicate PSA50 and PSA90 declines. B, Best percentage change in size of tumor target lesions. Dashed line indicates 30% reduction in tumor SLD from baseline. C, Example of patient showing response by PSA and radiographic assessments: CT scan and PSA curve over time of a heavily pretreated 65-year-old patient with stage IV prostate adenocarcinoma. Patient was enrolled into Cohort 11 (3-step 1.5 mg target dose of xaluritamig). CT scans showed three target lesions (two liver, one lymph node) and multiple nontarget lesions in the liver as well as two lymph nodes during screening. Patient achieved 99% PSA decline from baseline on C7D1 and PR (37.3% reduction of target lesions) after 2 cycles, which was confirmed at 16 weeks and maintained after 24 weeks. AEs occurred during C1 of treatment and included recurrent CRS, tinea faciei (both grade 1), rash, and worsening of back pain (both grade 2). During further treatment cycles, rash (grade 1), myalgia, and hyperkalemia (both grade 2) were reported. Patient remains on treatment at the time of publication. Red arrows indicate sites of tumor. D, Time on treatment for patients in high-dose cohorts. PSA and RECIST responses [RECIST evaluable (gray bars) and non–RECIST evaluable (white bars)] are presented for patients in high-dose cohorts. Patients whose treatment was ongoing are noted by an arrowhead. Double parallel lines (//) represent patients who have extended beyond 48 weeks: one patient is ongoing treatment at 90 weeks, one is ongoing treatment at 84 weeks, and one ended treatment at 58 weeks. NE, not evaluable; PD, progressive disease; SD, stable disease; SLD, sum of longest diameters.