Adjuvant pembrolizumab improves DFS in certain patients with urothelial carcinoma
Treatment with adjuvant pembrolizumab (Keytruda) reduced the risk of disease recurrence or death versus observation in patients with localized muscle-invasive urothelial carcinoma (MIUC) and locally advanced urothelial carcinoma, according to findings from the phase 3 AMBASSADOR trial (NCT03244384).1
“These positive results highlight the potential of Keytruda to prevent recurrence after surgery for patients with localized muscle-invasive or locally advanced urothelial carcinoma,” said Marjorie Green, MD, senior vice president and head of late-stage oncology, global clinical development, Merck Research Laboratories.
Merck (MSD), the manufacturer of pembrolizumab, reported in a news release that an independent Data Monitoring Committee determined at a pre-specified interim analysis that treatment with the PD-1 inhibitor after surgery significantly improved disease-free survival (DFS) in this patient population. DFS is a co-primary end point of the trial along with overall survival (OS). The study is continuing in order to evaluate OS.
There were no new safety signals observed with pembrolizumab compared with previously published research with the immunotherapy. Merck plans to share the specific data from the trial at an upcoming meeting and communicate with regulatory authorities about the findings.
“Up to half of patients with bladder cancer who undergo surgery will experience recurrence within a year, underscoring the need for new treatment options in the adjuvant setting,” Marjorie Green, MD, senior vice president and head of late-stage oncology, global clinical development, Merck Research Laboratories, stated in the news release. “These positive results highlight the potential of Keytruda to prevent recurrence after surgery for patients with localized muscle-invasive or locally advanced urothelial carcinoma.”
Overall, the open-label phase 3 AMBASSADOR trial enrolled 702 patients with MIUC and locally advanced urothelial carcinoma. Patients were randomized to observation or post-surgery pembrolizumab at 200 mg IV every 3 weeks for a maximum of 18 cycles. The trial was sponsored by the National Cancer Institute and was open at more than 900 clinical sites.
Patients were monitored throughout the trial with CT, CT urography, and/or MRI. The study design allowed for patients to receive a cystoscopy and blood sample collection at the time of screening and on the study.
Pembrolizumab currently has several FDA approvals for the treatment of patients with urothelial carcinoma:
- Combined with enfortumab vedotin (Padcev) for cisplatin-ineligible patients with locally advanced or metastatic disease.
- As a monotherapy for patients with locally advanced or metastatic urothelial carcinoma who are ineligible for platinum-based chemotherapy or have experienced progressive disease at the time of or after treatment with platinum-based chemotherapy or ≤12 months of neoadjuvant or adjuvant platinum-based chemotherapy .
- As a monotherapy for patients with BCG-unresponsive, high-risk, non–muscle-invasive bladder cancer with carcinoma in situ with or without papillary tumors who are not eligible for or have chosen not to receive cystectomy.2
Regarding the adjuvant treatment of genitourinary cancers, pembrolizumab is approved by the FDA as an adjuvant therapy for patients with renal cell carcinoma who are at intermediate-high or high risk of having disease recurrence after undergoing nephrectomy, or after receiving nephrectomy and resection of metastatic lesions.2
References
1. KEYTRUDA significantly improved DFS as adjuvant therapy versus observation for patients with localized MIUC and locally advanced urothelial carcinoma. Published online October 5, 2023. Accessed October 5, 2023. https://www.merck.com/news/mercks-keytruda-pembrolizumab-met-primary-endpoint-of-disease-free-survival-dfs-in-certain-patients-with-muscle-invasive-urothelial-carcinoma-miuc-after-surgery
2. Highlights of prescribing information: KEYTRUDA® (pembrolizumab) injection, for intravenous use Initial U.S. Approval: 2014. https://www.merck.com/product/usa/pi_circulars/k/keytruda/keytruda_pi.pdf
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December 7th 2021“It's not a replacement for clinical judgment, obviously. But at the end of the day, the idea is that it shows you what your next steps are based on what the American Urological Association and [Society of Urologic Oncology] guidelines are for non-muscle invasive bladder cancer,” Chad R. Ritch, MD, MBA, FACS.
