Efficacy of Disitamab Vedotin in Treating HER2 2+/FISH- Gastric Cancer

Area of Science:

• Oncology
• Pharmacology
• Medical Case Study

Background:

• Advanced gastric cancer with systemic metastasis presents significant therapeutic challenges.
• Human epidermal growth factor receptor 2 (HER2) expression is a key factor in gastric cancer treatment strategies.
• Current therapies for metastatic gastric cancer have limited efficacy and progression-free survival.

Observation:

• A 56-year-old female patient with HER2-expressing metastatic gastric cancer received a complex first-line regimen including camrelizumab, oxaliplatin, apatinib, and a PS scheme (S-1 and paclitaxel).
• The patient experienced severe adverse reactions, necessitating a change in treatment.
• Second-line therapy involved replacing the PS scheme with disitamab vedotin, continuing camrelizumab and apatinib, which resulted in stable disease and improved tolerability.

Findings:

• The initial multi-agent therapy provided 3-month progression-free survival but was limited by severe toxicity.
• Disitamab vedotin, in combination with camrelizumab and apatinib, demonstrated efficacy in achieving stable disease and local tumor control.
• The patient achieved a 6-month progression-free survival with the second-line regimen, with only grade 1/2 adverse events.

Implications:

• Disitamab vedotin shows potential as a safe and effective therapeutic option for advanced gastric cancer patients with HER2 expression.
• Combination therapy including disitamab vedotin may offer a viable strategy for managing metastatic gastric cancer.
• Further clinical investigation is warranted to confirm the role of disitamab vedotin in HER2-positive gastric cancer treatment.