Drugs for advanced breast cancer could also be beneficial for patients with a rare cancer affecting parts of the digestive system, according to a recent trial. The drugs in question, tucatinib and trastuzumab, target a protein called human epidermal growth factor receptor 2 (HER2) in cancer cells to inhibit their growth and spread.
These drugs are currently recommended by the National Institute for Health and Care Excellence (Nice) as a treatment option for patients with HER2-positive locally advanced or metastatic breast cancer who have undergone two or more anti-HER2 therapies. Researchers have been exploring the potential of these drugs for treating other cancers, including bile duct cancer, also known as cholangiocarcinoma, which affects the small tubes connecting organs like the liver and gallbladder.
In a phase two trial involving 217 patients with various tumours that had spread in the body and displayed alterations in HER2, participants were administered tucatinib tablets twice daily and trastuzumab intravenously once every three weeks. The results showed that cancer shrank in 22.2% of all patients, with an even higher rate of 46.7% in the 30 patients specifically with bile duct cancer.
Dr. Yoshiaki Nakamura from the National Cancer Centre Hospital East in Kashiwa, Japan, highlighted the safety and tolerability of the chemotherapy-free combination, with minimal treatment discontinuations due to side effects. He noted the variable effects observed across different tumour types but emphasized the clinically relevant response rates seen in patients with HER2-positive metastatic bile duct cancer and HER2-mutated metastatic breast cancer.
Liver Cancer UK reports that approximately 2,200 individuals in England are diagnosed with bile duct cancer annually. These promising trial findings will be presented at the EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics in Barcelona. Dr. Tim Greten, co-chair of the symposium, underlined the importance of focusing on the molecular characteristics of tumours rather than their location, which opens up possibilities for treating rare cancers like bile duct cancer more effectively.
While early, the trial suggests that targeting HER2 with a combination of drugs could benefit a broader spectrum of breast cancer patients and some individuals with bile duct cancer. Further research is needed to confirm and expand upon these results, indicating a potential avenue for more treatment options in the future.
**Insights:**
The findings from this trial demonstrate the importance of exploring repurposing existing drugs for different types of cancer to provide more treatment options for patients with rare or hard-to-treat cancers. The success of targeting HER2 in advanced breast cancer and its potential benefits for bile duct cancer patients showcase the potential for personalised medicine approaches in oncology. This study highlights the significance of molecular profiling in determining treatment strategies, ultimately improving outcomes for cancer patients with diverse tumour types.