Pharmacokinetics, Pharmacodynamics, Safety and Immunogenicity of CMAB807, a New Denosumab Biosimilar, in Healthy Chinese Subjects

Phase I, Randomized, Placebo-Controlled, Dose-Escalation Study of GB223, a Fully-Humanized Monoclonal Antibody to RANKL, in Healthy Chinese Adults

BACKGROUND

GB223 is a novel, fully-humanized monoclonal antibody against the receptor activator of nuclear factor-kappa B ligand (RANKL). In this phase I study, the safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity of GB223 were investigated.

PATIENTS AND METHODS

This was a randomized, double-blinded, placebo-controlled, single-dose escalation study conducted in 44 healthy Chinese adults. Participants were randomly assigned to receive a single subcutaneous injection dose of 7, 21, 63, 119, or 140 mg of GB223 (n = 34) or placebo (n = 10) and were followed up for 140-252 days.

RESULTS

The results of noncompartmental analysis showed that GB223 was slowly absorbed after dosing, with a time to reach maximum concentration (Tmax) ranging from 5 to 11 days. Serum GB223 concentrations decreased slowly, with a long half-life ranging from 7.91 to 19.60 days. A two-compartment Michaelis-Menten model was found to best describe the pharmacokinetics of GB223, and the absorption rate of GB223 differed between males (0.0146 h-1) and females (0.0081 h-1). Serum C-terminal telopeptide of type I collagen decreased significantly postdose, and the inhibition lasted 42-168 days. No deaths or drug-related serious adverse events occurred. The most frequent adverse events were blood parathyroid hormone increased (94.1%), blood phosphorus decreased (67.6%) and blood calcium decreased (58.8%). In the GB223 group, 44.1% (15/34) of subjects were antidrug antibody positive after dosing.

CONCLUSION

In this study, we demonstrated for the first time that a single subcutaneous injection of GB223, from 7 to 140 mg, is safe and well tolerated in healthy Chinese subjects. GB223 has a nonlinear pharmacokinetic profile, and sex was a potential covariate that may affect the absorption rate of GB223.

CLINICAL TRIAL REGISTRATION

NCT04178044 and ChiCTR1800020338.

Cancer Treatment-Induced Bone Loss: Role of Denosumab in Non-Metastatic Breast Cancer

Chemotherapeutic agents, endocrine therapy and radiotherapy used in the management of breast cancer are known to cause decreased bone mineral density, and thus, increased incidence of fractures. A majority (~60%) of the breast cancer patients in India are either estrogen (ER) or progesterone hormone receptor (PR) positive. Adjuvant treatment with aromatase inhibitors (AIs) is the treatment mainstay for hormone-sensitive disease in postmenopausal (PM) women, with reduced bone mineral density (BMD), which results in increased fracture rates. Zoledronic acid, alendronate, risedronate and denosumab have been the agents of choice for managing bone loss. Denosumab 60 mg is approved for gaining bone mass in women with breast cancer who are at high risk for fracture following adjuvant AI treatment. The phase III HALT-BC data indicate an improvement in BMD with denosumab and a 50% reduction in clinical fractures, with significant improvements seen at the lumbar spine, distal third of the radius, and total hip. Denosumab has several advantages over other bone modifying agents such as subcutaneous self-administration by the patient themselves, no requirement of hospitalization, no dose modifications in renal impairment, and low incidence of acute phase anaphylactic reactions. We review the available evidence of denosumab for managing bone loss in non-metastatic breast cancer patients.

A Randomized Controlled Dose-Escalation Study of LY06006, a Recombinant Humanized Monoclonal Antibody to RANKL, in Chinese Healthy Adults

Background: This study was conducted to explore the safety, tolerance, pharmacokinetics, pharmacodynamics, and immunogenicity of LY06006, a recombinant humanized monoclonal antibody to RANKL, when administrated subcutaneously in Chinese healthy adults.

Research design and methods: This was a randomized, double-blinded, placebo-controlled, single ascending dose study performed in 32 healthy Chinese adults, who were randomly assigned to receive a single injection dose of 18, 60, 120 mg study drug or placebo with a follow-up of 140–252 days.

Results: No deaths or drug-related serious adverse events occurred. LY06006 was rapidly absorbed in the 60 mg group with a T_max range of 120–480 h and serum LY06006 concentrations decreased slowly 11–13 days after dosing with a long mean (SD) half-life of 389.58 (63.44) h. The most frequent AEs were elevated serum parathyroid hormone (PTH) level (83.3%), hypocalcemia (54.2%), and hypophosphatemia (45.8%). None of the 32 subjects tested positive for anti-drug antibody during the trial.

Conclusion: Single-dose subcutaneous administration of LY06006 was safe and well-tolerated in healthy Chinese adults. C_max showed linear pharmacokinetic characteristics in the dose range of 18–120 mg based on dose-exposure proportionality analysis.