Phase I study of the safety and clinical activity of the interleukin-8 inhibitor AMY109 combined with atezolizumab in patients with advanced solid cancers.

BACKGROUND: Immunosuppressive conditions within the tumor microenvironment (TME) can allow tumors to evade the immune system, including by hampering programmed death ligand 1 (PD-L1) inhibitor activity. Interleukin (IL)-8 contributes to immunosuppression and fibrosis in the TME. AMY109, a humanized anti-IL-8 monoclonal antibody, reduced fibrosis and decreased immunosuppressive cells in tumor tissue in animals. Combining AMY109 with atezolizumab (anti-PD-L1 antibody) may enhance its antitumor effects by making the TME more favorable to PD-L1 inhibition. METHODS: This multicenter, open-label, dose-escalation study evaluated the safety, pharmacokinetics, and clinical activity of AMY109 plus atezolizumab in patients with previously treated advanced solid tumors and Eastern Cooperative Oncology Group performance status 0 or 1. Patients received AMY109 (2-45 mg/kg) plus atezolizumab (1200 mg) intravenously every 3 weeks in part 1, and AMY109 (15-45 mg/kg) plus atezolizumab (1200 mg) in part 2. Primary endpoints were the dose-limiting toxicity (DLT), safety, and pharmacokinetics of AMY109 and atezolizumab in Part 1, and safety and antitumor activity per investigator-assessed Response Evaluation Criteria in Solid Tumors 1.1 in part 2. Exploratory analyses of peripheral and tumor biomarker were conducted. RESULTS: Overall, 38 patients (18 in part 1 and 20 in part 2) were enrolled. Part 1 showed no DLTs and a dose-proportional increase in AMY109 exposure over 2-45 mg/kg, with no apparent change in mean atezolizumab serum concentrations across AMY109 dosing. Plasma IL-8 concentration accumulation was seen in all dose cohorts after AMY109 initiation. Grade 1-3 treatment-related adverse events (AEs) occurred in 21 of 38 patients (55%). Treatment-related serious AEs occurred in two patients (5%). No AEs led to treatment withdrawal. Partial responses (PRs) occurred in 2 of 38 patients; the confirmed objective response rate was 5%. These patients had uterocervical and pancreatic cancer, respectively, and had been treated for >500 days at the cut-off date: one had received 45 mg/kg of AMY109 throughout, and the other received 30 mg/kg of AMY109 until cycle 5, then 45 mg/kg thereafter. CONCLUSIONS: With no DLTs, AMY109 plus atezolizumab was well tolerated in patients with advanced solid tumors, with no new safety signals. AMY109 showed a dose-proportional increase in exposure. The PRs in two patients were durable.

Anti-pruritic effect of nemolizumab in hemodialysis patients with uremic pruritus: a phase II, randomized, double-blind, placebo-controlled clinical study.

BACKGROUND: The pathophysiology of uremic pruritus (UP), which is characterized by systemic and intractable itching, remains unclear. As interleukin (IL)-31 may be involved, we conducted a phase II, randomized, controlled study to evaluate nemolizumab (anti-IL-31 receptor A antibody) in Japanese hemodialysis patients with UP. METHODS: Patients were randomly assigned (1:1:1:1:1) to one of four double-blind groups (receiving a single subcutaneous injection of nemolizumab 0.125, 0.5, or 2.0 mg/kg, or placebo on Day 1) or an open-label reference group (receiving oral nalfurafine hydrochloride 2.5-5 µg once daily for 12 weeks). The primary endpoint was the difference in the absolute change in pruritus visual analog scale (VAS) at Week 4 between placebo and each nemolizumab group. RESULTS: The primary efficacy endpoint was not met. The mean change from baseline with all three nemolizumab doses at Week 1, and with 0.5 mg/kg at Week 4, was greater than with placebo. Least square mean differences (95% confidence intervals) in the absolute changes between the placebo arm and each nemolizumab arm were - 2.4 (- 19.7, 14.9) for 0.125 mg/kg, - 8.7 (- 26.6, 9.2) for 0.5 mg/kg, and 0.4 (- 17.0, 17.8) for 2.0 mg/kg. Secondary efficacy parameters including the Shiratori severity score and 5-D itch score failed to show between-group differences. Patients with higher serum IL-31 levels at screening tended to have greater pruritus VAS reductions following nemolizumab treatment. CONCLUSIONS: In this phase II study in patients with UP, the primary efficacy parameter was not met. Nemolizumab was generally well tolerated with no clinically significant safety concerns. CLINICAL TRIAL REGISTRATION: JAPIC: JapicCTI-152961, https://www.clinicaltrials.jp/cti-user/trial/ShowDirect.jsp?japicId=JapicCTI-152961 .

Antibody recycling by engineered pH-dependent antigen binding improves the duration of antigen neutralization.

For many antibodies, each antigen-binding site binds to only one antigen molecule during the antibody's lifetime in plasma. To increase the number of cycles of antigen binding and lysosomal degradation, we engineered tocilizumab (Actemra), an antibody against the IL-6 receptor (IL-6R), to rapidly dissociate from IL-6R within the acidic environment of the endosome (pH 6.0) while maintaining its binding affinity to IL-6R in plasma (pH 7.4). Studies using normal mice and mice expressing human IL-6R suggested that this pH-dependent IL-6R dissociation within the acidic environment of the endosome resulted in lysosomal degradation of the previously bound IL-6R while releasing the free antibody back to the plasma to bind another IL-6R molecule. In cynomolgus monkeys, an antibody with pH-dependent antigen binding, but not an affinity-matured variant, significantly improved the pharmacokinetics and duration of C-reactive protein inhibition. Engineering pH dependency into the interactions of therapeutic antibodies with their targets may enable them to be delivered less frequently or at lower doses.