This is a phase Ⅲ, multicenter, randomized, double-blind, study to evaluate the efficacy and safety of JMT103 in patients with bone metastases from malignant solid tumors. The purpose of this study is to determine if JMT103 is non-inferior to zoledronic acid.

Inclusion Criteria:

1. Age: older than 18 years;
2. Breast cancer, prostate cancer, lung cancer and other solid tumors diagnosed by histological or cytological examination (prostate patients should also meet: castration-resistant prostate cancer with serum testosterone <50 ng/dL or 1.7 nmol/L and serum PSA progression after surgery or drug castration treatment);
3. Patients with imaging studies showing at least one tumor bone metastasis;
4. With a good organ function;
5. Expected survival of at least 6 months.

Exclusion Criteria:

1. Previous or ongoing osteomyelitis or osteonecrosis of the jaw; dental or oral surgery; acute dental or jaw disease requiring oral surgery; invasive dental procedures planned during the study; patients with pulpitis during the screening period;
2. Radiotherapy or surgery for the bone metastases is planned during the study;
3. Patients with brain metastasis or meningeal metastasis (patients with neurological symptoms should undergo MRI/CT examination to exclude patients with brain metastasis);
4. Patients with bone metabolic diseases [e.g., Paget's disease, Cushing's syndrome, hyperprolactinemia, hyperthyroidism/hypothyroid (except for hypothyroidism with normal TSH, FT3, and FT4 after stable thyroid hormone replacement therapy, and subclinical hypothyroidism that does not need to be treated), hyper/hypoparathyroidism, etc.];
5. Uncontrolled concurrent diseases, including but not limited to: uncontrolled diabetes mellitus (≥grade 3, NCI-CTCAE 5.0), symptomatic congestive heart failure, hypertension (BP> 150/90 mmHg after standard therapy), unstable angina, arrhythmia requiring medical or instrumental treatment, history of myocardial infarction within 6 months, echocardiography with left ventricular ejection fraction <50%;
6. Treatment with anti-RANKL antibody, bisphosphonates (except for bone scan purposes) within 6 months prior to the first dose;
7. Patients considered by the investigator as unsuitable for this study (such as poor compliance, etc.).

Double-blind