The following are side effects that have been reported by other patients while on treatment with the  GPRC5D-targeting bispecific antibody talquetamab. 

Cytokine Release Syndrome (CRS)

• 76% overall 
  • Grade 1: 57%
  • Grade 2: 17%
  • Grade 3: 1.5%
• The median time of onset was 27 hours after the most recent dose
• Symptoms lasted a median of 17 hours

Neurological Toxicity and ICANS

• 55% overall neurological toxicity 
  • Grade 3-4 neurological toxicity was reported in 6% of patients 
• ICANS reported in 9% of patients 
• The median time to onset was 2.5 days after the most recent dose 
• Symptoms lasted a median of 2 days

Infections

Because it targets GPRC5D, the risk of severe infection is not as high for talquetamab as it is for the bispecific antibodies that target BCMA (found commonly on the surface of immune-protecting plasma cells). 

• Serious infections occurred in 16% of patients
  • 17% of the reported infections were grade 3 or 4 
  • 1.5% of the reported infections were fatal 

Talquetamab-Related Side Effects and Management

In addition to myeloma cells, the protein GPRC5D (talquetamab's target) is also found on the surface of rapidly dividing cells in the body, such as those in the mouth, tongue, and throat. This often leads to side effects in these areas, such as significant changes in taste, difficulty swallowing, or a metallic sensation that persists within the mouth. 

Hair, nail, and skin cells are other rapidly dividing cells that share the GPRC5D protein. Therefore, talquetamab can also affect these areas of the body. 

Watch the video below to learn from Dr. Ajai Chari's experience treating over 150 patients with talquetamab and how he managed dysgeusia, skin-related side effects, and weight loss to make sure his patients could remain on treatment.

Oral-Related Toxicities and Weight Loss 

• 80% of patients had oral-related toxicities 
  • Abnormal taste (dysgeusia): 49%
  • Dry mouth: 34%
  • Difficulty swallowing: 23%
  • Loss of taste: 18% 
• 62% of patients experienced weight loss, regardless of having an oral-related toxicity 

Skin Toxicities 

• 62% of patients experienced skin reactions/rashes 
• The median time to onset was 25 days 
• The median time to improvement was 33 days

For more information on talquetamab's safety profile, visit TALVEY Medication Guide