HER2-Targeting Antibody-Drug Conjugate in Advanced Urothelial Carcinoma
Posted: Thursday, December 10, 2020
A recent study conducted by Jun Guo, MD, of Peking University Cancer Hospital & Institute, Beijing, China, and colleagues assessed the efficacy and safety of RC48-ADC—an HER2-targeting antibody-drug conjugate with monomethyl auristatin E—in patients with HER2-positive locally advanced or metastatic urothelial carcinoma. They found that patients achieved higher objective response rates and progression-free survival with the novel agent than other immune checkpoint inhibitors. Their results were published in Clinical Cancer Research.
This phase II, open-label, multicenter, single-arm clinical trial examined the objective response rate of RC48-ADC in patients with HER2-positive locally advanced or metastatic urothelial carcinoma who previously failed to respond to prior systemic chemotherapy. A total of 43 eligible patients were treated with RC48-ADC at 2.0 mg/kg over 30 to 90 minutes once every 2 weeks until disease progression, intolerable toxicity, death, or withdrawal of consent. The treatment dose was modified and interrupted for up to 28 days in patients experiencing treatment-related adverse events until they resolved to grade 0/1 or baseline. The median follow-up at the cutoff date was 20.3 months.
The objective response rate was 51.2% (n = 22), and 39.5% (n = 17) experienced stable disease as best response. In 88.4% of patients (n = 38), tumor shrinkage was observed. The median duration of response was 6.9 months, and progression-free survival was observed in 59.1% of patients at 6 months. Median overall survival was 13.9 months. Patients with higher HER2 expression achieved higher objective response rates than patients with lower HER2 expression.
“The objective response rate and progression-free survival of this trial show disease efficacy for HER2-expressing metastatic urothelial cancer,” explained the researchers. “RC48-ADC has the potential to become a treatment option for metastatic urothelial carcinoma with HER2 overexpression,” they concluded.
Disclosure: For full disclosures of the study authors, visit clincancerres.aacrjournals.org.