UNLOXCYT Solution for injection Ref.[115485] Active ingredients: Cosibelimab

PD-L1 may be expressed on tumor cells and tumor-infiltrating immune cells and can contribute to the inhibition of the anti-tumor immune response in the tumor microenvironment. Binding of PD-L1 to the PD-1 and B7.1 receptors found on T cells and antigen presenting cells suppresses cytotoxic T-cell activity, T-cell proliferation, and cytokine production. Cosibelimab-ipdl binds PD-L1 and blocks the interaction between PD-L1 and its receptors PD-1 and B7.1. This interaction releases the inhibitory effects of PD-L1 on the anti-tumor immune response. Cosibelimab-ipdl has also been shown to induce antibody-dependent cell-mediated cytotoxicity (ADCC) in vitro.

Cosibelimab-ipdl exposure-response relationships and the time course of pharmacodynamic responses have not been fully characterized.

Cosibelimab-ipdl pharmacokinetic parameters are presented as geometric mean (coefficient of variation) unless otherwise stated. At the recommended dosage, the cosibelimab-ipdl steady-state maximum plasma concentration (C_max) is 492 µg/mL (24.3%) and area under curve (AUC) is 112000 µg*h/mL (39.6%). Cosibelimab-ipdl C_max and AUC increased proportionally over the dose range of 800 mg to 1,200 mg following single dosing. Steady-state concentrations of cosibelimab-ipdl are reached by 12 weeks.

At 1,200 mg every 3 weeks, the mean cosibelimab-ipdl concentrations (coefficient of variation, CV%) at steady-state ranged between a minimum concentration of 120 µg/L (46.3%) and a maximum concentration of 453 µg/L (22.2%). Steady-state exposure was achieved after 84 days of treatment.

In patients with CSCC, cosibelimab-ipdl steady-state exposure at 1,200 mg every 3 weeks (the recommended dosage) was comparable to the exposure at 800 mg every 2 weeks.

Distribution

Cosibelimab-ipdl steady state volume of distribution is approximately 5.67 L (19.7%).

Elimination

Cosibelimab-ipdl steady state elimination half-life is 17.8 days (43.8%), and the clearance is 0.256 L/day (41%).

Specific Populations

No clinically significant differences in the pharmacokinetics of cosibelimab-ipdl were observed based on age (24.8 to 95.0 years), sex, race (79.6% White, 10.7% Asian, 0.5% African American, and 1.5% other), ethnicity (76.9% Not Hispanic/Latino and 4.9% Hispanic/Latino), ADA and nAb status, albumin (22 to 51 g/L), tumor type, tumor diameter, and renal impairment (CLcr 15 mL/min and higher). The effect of severe hepatic impairment (bilirubin >3 × ULN and any AST) on cosibelimab-ipdl pharmacokinetics is unknown.

No studies have been performed to assess the potential of cosibelimab-ipdl for carcinogenicity or genotoxicity.

Fertility studies have not been conducted with cosibelimab-ipdl in animals. In 1- and 3-month repeat-dose toxicology studies in monkeys, there were no notable effects in the male and female reproductive organs up to the highest dose tested of 100 mg/kg/dose; however, many animals in these studies were not sexually mature.

In animal models, inhibition of PD-L1/PD-1 signaling increased the severity of some infections and enhanced inflammatory responses. Mycobacterium tuberculosis-infected PD-1 knockout mice exhibit markedly decreased survival compared with wild-type controls, which correlated with increased bacterial proliferation and inflammatory responses in these animals. PD-L1 and PD-1 knockout mice and mice receiving PD-L1–blocking antibody have also shown decreased survival following infection with lymphocytic choriomeningitis virus.

14.1. Cutaneous Squamous Cell Carcinoma (CSCC)

The efficacy of UNLOXCYT was evaluated in Study CK-301-101 (NCT03212404), a multicenter, multicohort, open-label study in patients with metastatic CSCC (mCSCC) or locally advanced CSCC (laCSCC) who were not candidates for curative surgery or curative radiation. Patients were excluded if they had the following: active or suspected autoimmune disease, allogeneic transplant within 6 months prior to treatment, prior treatment with anti–PD-1/PD-L1 blocking antibodies or other immune checkpoint inhibitor therapy, uncontrolled or significant cardiovascular disease, ECOG PS ≥2, or infection with HIV, hepatitis B or hepatitis C.

Patients received UNLOXCYT 800 mg every 2 weeks until disease progression or unacceptable toxicity. Tumor response assessments were performed every 8 weeks for the first 8 months and every 12 weeks thereafter.

The major efficacy outcomes were objective response rate (ORR) and duration of response (DOR) as assessed by an independent central review committee (ICR) according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. For patients with laCSCC with externally visible target lesions not assessable by radiologic imaging, ORR was determined by ICR assessments of digital photography (WHO criteria).

The efficacy population consisted of 109 patients. The median age was 75 years (range 37-95); 78% were ≥65 years; 72% were male; 85% were White; 6% were Asian; 1% were Black or African American; 7% were race unknown or missing; 34% had ECOG performance status of 0 and 66% had ECOG performance score of 1. Seven percent of patients received at least one prior anti-cancer systemic therapy, 66% of patients had prior surgery and 69% of patients had prior radiotherapy. Efficacy results are summarized in Table 4.

Table 4. Efficacy Results for Study CK-301-101:

CI: confidence interval; NR: not reached; +: Denotes ongoing at last assessment.
^* Based on Kaplan-Meier estimate.
^† The numerator includes the number of patients whose observed DOR reached at least the specified times of 6 or 12 months. Patients who did not have the opportunity to reach the specified timepoint were included in the denominator only.