Talquetamab is a GPRC5D/CD3 bispecific antibody approved by the U.S. FDA in 2023 for the treatment of relapsed or refractory multiple myeloma.

Precautions for the Administration of Talquetamab

Confirmation of Indications

Talquetamab is indicated for adult patients with relapsed or refractory multiple myeloma who have previously received at least 4 lines of treatment, including proteasome inhibitors, immunomodulatory agents, and anti-CD38 monoclonal antibodies.

This indication was approved under the accelerated approval pathway, and further confirmatory trials are required to verify clinical benefits.

Requirements for Baseline Examinations

Laboratory Tests: Complete blood count, liver function (ALT/AST/bilirubin), and electrolyte levels.

Infection Screening: Assessment of active infections, including bacterial, fungal, and viral infections.

Neurological Evaluation: Baseline cognitive function and neurological status.

Administration in Special Populations

Pregnant Women: May cause fetal harm. Contraception should be used during treatment and for 3 months after the last dose.

Lactating Women: Breastfeeding is not recommended during treatment and for 3 months after the last dose.

Elderly Patients: Caution is required for patients aged 75 years and above, as they may have an increased risk of fatal adverse reactions.

Patients with Hepatic or Renal Impairment: No dose adjustment is needed for patients with mild to moderate impairment; limited data are available for patients with severe impairment.

Treatment Monitoring of Talquetamab

Monitoring for Cytokine Release Syndrome (CRS)

Main Manifestations - Common Symptoms: Fever (83%), hypotension (21%), and hypoxia (11%).

Grade-Based Management:

Grade 1: Discontinue administration until symptoms resolve.

Grade ≥2: Hospitalize for 48-hour monitoring; administer tocilizumab/glucocorticoids if necessary.

Monitoring for Neurotoxicity

Immune Effector Cell-Associated Neurotoxicity Syndrome (ICANS) (Incidence: 9%): Altered level of consciousness, disorientation, and language impairment.

Other Neurotoxicities: Peripheral neuropathy (14%), headache (21%), and tremor (11%).

Management Requirements: Immediately discontinue administration when symptoms occur, and consider consultation with a neurologist.

Monitoring for Oral Toxicity

Common Manifestations: Taste disturbance (49%), xerostomia (dry mouth) (34%), and dysphagia (difficulty swallowing) (23%).

Weight Monitoring: 62% of patients experience weight loss, and 29% have a weight loss of ≥10%.

Interventions: Provide nutritional support and symptom management; discontinue administration in severe cases.