Background: Denosumab has been approved for the treatment of bone metastases from solid tumors. QL1206 is the first denosumab biosimilar and needs to be compared with denosumab in a phase III trial.
Objective: This phase III trial aims to compare the efficacy, safety, and pharmacokinetics between QL1206 and denosumab in patients with bone metastases from solid tumors.
Methods: This randomized, double-blind, phase III trial was conducted in 51 centers in China. Patients aged 18-80 years, with solid tumors and bone metastases, and an Eastern Cooperative Oncology Group performance status of 0-2 were eligible. This study was divided into a 13-week double-blind period, a 40-week open-label period, and a 20-week safety follow-up period. In the double-blind period, patients were randomly assigned (1:1) to receive three doses of QL1206 or denosumab (120 mg subcutaneously every 4 weeks, each). Randomization was stratified by tumor types, previous skeletal-related events, and current systemic anti-tumor therapy. In the open-label period, up to ten doses of QL1206 could be given in both groups. The primary endpoint was percentage change in urinary N-telopeptide/creatinine ratio (uNTX/uCr) from baseline to Week 13. Equivalence margins were ± 0.135. Secondary endpoints included percentage change in uNTX/uCr at Week 25 and 53, percentage change in serum bone-specific alkaline phosphatase at Week 13, 25, and 53, and time to on-study skeletal-related events. The safety profile was evaluated based on adverse events and immunogenicity.
Results: From September 2019 to January 2021, in the full analysis set, 717 patients were randomly assigned to receive QL1206 (n = 357) or denosumab (n = 360). Median percentage changes in uNTX/uCr at Week 13 in two groups were - 75.2% and - 75.8%, respectively. Least-squares mean difference in the natural log-transformed ratio of uNTX/uCr at Week 13 to baseline between the two groups was 0.012 (90% confidence interval - 0.078 to 0.103), within the equivalence margins. There were no differences in the secondary endpoints between the two groups (all p > 0.05). Adverse events, immunogenicity, and pharmacokinetics were similar in the two groups.
Conclusions: Denosumab biosimilar QL1206 had promising efficacy, tolerable safety, and pharmacokinetics equivalent to denosumab and could benefit patients with bone metastases from solid tumors.
Clinical trial registration: ClinicalTrials.gov Identifier: NCT04550949, retrospectively registered on 16 September, 2020.
© 2023. The Author(s).