JMT103 is a novel, full human IgG4 monoclonal antibody targeting RANKL. In preclinical studies, JMT103 demonstrated strong activity through blocking RANKL receptor, RANK on the surface of osteoclasts, leading to inhibit osteoclast differentiation, activation, and maturation and reduce bone resorption.

This first-in-human study is conducted to assess the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) ,to evaluate the safety, pharmacokinetics and preliminary efficacy (bone turnover markers) of recombinant fully human Anti-RANKL Monoclonal Antibody (JMT103) in patients with bone metastases from tumors at single doses and multiple doses.

About 36 cases patients are to be recruited.

This is a Phase I, first-in-human, multi-center, open-label dose escalation clinical study of recombinant fully human Anti-RANKL Monoclonal Antibody (JMT103) administered subcutaneously to patients with bone metastases from tumors.

The study includes two phases: dose escalation study and expansion study. The dose-escalation stage is designed to evaluate the safety, tolerability, and pharmacokinetics of single dose and following repeat doses of JMT103 given every 4 weeks (Q4W) for three times. The expansion study stage is designed to evaluate the safety, tolerability, and pharmacokinetics of repeat doses of JMT103 given every 4 weeks (Q4W) for three times.

Inclusion Criteria:

• histologically or cytologically confirmed malignant solid tumors;
• imaging examination shows at least one site with bone metastases from tumors;
• ECOG performance status of score 0 or 1;
• Expected survival time ≥ 7.5 months.

Exclusion Criteria:

• Previous or present osteomyelitis or osteonecrosis of the jaw; unhealed dental or oral surgery wounds; acute disease of the tooth or jaw requiring oral surgery; and invasive dental surgery planned to be received during the study;
• It is planned to perform therapeutic radiotherapy or orthopedic surgery for patients during the study;
• Known active brain metastases or leptomeningeal metastases. The subjects with neurological symptoms should receive brain CT/MRI to ensure that there have no metastases;
• Patients with bone metabolic diseases (Paget's disease, Cushing syndrome and hyperprolactinemia), rheumatoid arthritis, and current hyperparathyroidism or parathyroid dysfunction;
• Uncontrolled complications
• Active bacterial or fungal infections requiring systematic treatment within 7 days before the screening;
• Patients with HIV infections or active hepatitis;
• Pregnancy (positive serum β-HCG result) or lactation;

Open