Cusatuzumab, a CD70-directed monoclonal antibody, had antitumor activity in highly pre-treated patients with CD70-positive relapsed/refractory cutaneous T-cell lymphoma (CTCL), according to a recent study.
Nicolas Leupin, MD, PhD, of Argenx, and colleagues, conducted the study and published its results in Cancer.
The study, which was a cohort expansion of the ARGX-110-1201 study, included 27 patients with R/R CTCL who received cusatuzumab 1 mg/kg (n=11) or cusatuzumab 5 mg/kg (n=16) once every three weeks.
The overall response rate was 23%, including one complete response and five partial responses in 26 of the 27 evaluable patients. The authors additionally reported that nine patients “achieved stable disease.” The mean duration of treatment was 5.2 months, and the median duration was 2.5 months. Patients who had Sézary syndrome achieved a 60% partial response rate with a dosage of 5 mg/kg and a 33% partial response rate with a dosage of 1 mg/kg. There was an overall response rate of 50% for patients with Sézary syndrome.
Infusion-related reactions, pyrexia and asthenia were the most common adverse events reported. The researchers reported 18 serious adverse events in 11 patients. Only one serious adverse event, vasculitis, was related to the treatment.
Anti-drug antibodies affected the minimal concentration and resulted in “undetectable cusatuzumab concentrations at the end of treatment and, in some cases, a loss of response” in most of the patients (72.7%) receiving cusatuzumab 1 mg/kg, according to the investigators. However, “this effect was greatly reduced” in the patients receiving 5 mg/kg, the authors reported.
“Cusatuzumab was well tolerated, and antitumor activity was observed at both 1 and 5 mg/kg in highly pretreated patients with [relapsed/refractory] CTCL. The observed dose-dependent effect on exposure supports the use of 5 mg/kg for future development,” the authors concluded.
Leupin N, Zinzani PL, Morschhauser F, et al. Cusatuzumab for treatment of CD70-positive relapsed or refractory cutaneous T-cell lymphoma. Cancer. 2022;128(5):1004-1014. doi:10.1002/cncr.34005