Junlitai (Narlumosbart) – GCTB | HongKong DengYue Medicine

Narlumosbart Application Scope

• Therapeutic Area: Oncology, Musculoskeletal Disorders.

• Approved Indication: Treatment of adults and skeletally mature adolescents with giant cell tumor of bone (GCTB) that is unresectable or where surgery is likely to result in severe functional impairment.

Narlumosbart Characteristics

• Ingredients: Narlumosbart

• Properties:​ A clear, colorless to pale yellow liquid

• Packaging Specification:​ 120 mg (1.6 ml)/vial

• Storage:​ Store at 2°C to 8°C

• Expiry Date: Must be taken from the actual carton or prescribing information accompanying your specific vial

• Executive Standard: ​Must be taken from the actual carton or prescribing information accompanying your specific vial

• Approval Number: 国药准字 S20230047

• Date of Revision: This is product-specific and should be checked on the latest package insert

• Manufacturer: CSPC Pharmaceutical Group Limited

Guidelines for the Use of Narlumosbart

• Dosage and Administration:

  • Recommended Dose:

    • Loading Dose (Cycles 1-4): 120 mg administered as three separate 40 mg injections at different sites on Days 1, 8, and 15 of a 4-week cycle.

    • Maintenance Dose (Starting from Cycle 5): 120 mg administered as a single injection once every 4 weeks.

  • Administration:

    • Route: For subcutaneous injection only.

    • Injection Sites: Abdomen, thigh, or upper arm. Rotate injection sites.

  • Missed Dose:​ If a dose is missed, administer the subcutaneous injection as soon as possible. Thereafter, the dosing schedule should be adjusted to maintain the every-4-week interval. Consult the prescribing physician for specific guidance.

• Adverse Reactions:

  • Common Adverse Reactions:

    • In clinical trials (e.g., treatment of bone metastases), common treatment‑related events included hypophosphatemia (≈ 30.5%), hypocalcemia (~ 23.7%), and hypermagnesemia (~ 10.2%), among others.

    • In bone‑metastasis study, no treatment‑related serious adverse events were reported.

    • In a 2024–2025 phase II study in postmenopausal osteoporosis, JMT103 was generally well tolerated; treatment‑related adverse events were similar across groups; no drug-related severe adverse events reported.

    • In the real‑world / clinical‑trial data for GCTB, reported adverse reactions included reversible low calcium / low phosphate; incidence of grade ≥ 3 adverse reactions was low (2.2%), and no cases of osteonecrosis of jaw (ONJ) occurred in the reported cohort.

  • Serious Adverse Reactions: Given mechanism: risk of hypocalcemia/hypophosphatemia; as with other anti‑RANKL therapies, potential risk of bone turnover suppression, impaired bone remodeling, possibly jaw osteonecrosis with dental procedures—though publicly disclosed data remain limited.

    ​

• Contraindications:

• Precautions:

  • Dental or jaw conditions: active osteomyelitis, non‑healed dental/oral surgery, planned invasive dental procedures during therapy—these may exclude patients from therapy.

  • Use only via subcutaneous injection; other routes contraindicated.

  • Monitoring of calcium/vitamin D status, bone metabolism markers, and dental health recommended. Because long-term safety data remain limited, careful follow-up is warranted.

Narlumosbart Interactions

• As a monoclonal antibody, Narlumosbart is not metabolized via cytochrome P450 or typical small-molecule pathways, so classic drug–drug interactions via CYP enzymes are not expected.

• However: combining with bisphosphonates is not recommended (per prescribing info)

 

Note:

• If there is a new packaging for the drug, the new packaging shall prevail. The above information is sourced from DengYue Medicine.
•  This content is for reference only. Prescription drugs must be used under a doctor’s guidance and purchased from authorized sources.