(UroToday.com) The 2024 American Society of Clinical Oncology (ASCO) Annual Meeting held in Chicago, IL was host to a kidney and bladder cancers poster session. Dr. Gliceida Fortuna presented an analysis of treatment pattern changes and attrition rates in patients with metastatic clear cell renal cell carcinoma (ccRCC).
The treatment landscape of metastatic ccRCC has rapidly evolved with the approval of systemic therapy combinations of immune checkpoint inhibitors (anti-PD-[L]-1) plus either cytotoxic T lymphocyte-associated protein 4 (CTLA4) or vascular endothelial growth factor receptor tyrosine kinase (TKI) inhibitors. Despite the level one evidence supporting these regimens and regulatory approval for their use in clinical practice, clinical implementation strategies to improve the uptake of these agents in real-world practice remain of utmost importance. In this study, the investigators sought to evaluate real-world treatment trends and attrition rates both before and after PD-1 inhibitor approvals in the United States using a large real-world US-based cohort.
This was a retrospective analysis using the nationwide Flatiron Health electronic health record (EHR)-derived de-identified database. The investigators included patients with metastatic ccRCC diagnosed between January 2011 and January 2022 who received systemic therapy. Patients requiring systemic therapy for ≥2 malignancies were excluded. Based on the approval date of 4/16/2018 for the anti-PD-1 + CTLA4 combination of ipilimumab + nivolumab, patients were categorized into one of two cohorts:
- B2018 (1st line treatment received prior to 4/16/2018)
- A2018 (1st line treatment received after 4/16/2018)
Attrition rate analysis was performed one year after treatment discontinuation to identify patients who died, were alive but did not need treatment, or started next-line therapy. For this purpose, patients who discontinued or started each line of therapy after 1/31/2022 were censored from this analysis. Treatment received in each line of therapy was summarized using frequency counts and proportions/percentages. All analyses were done using R version 4.2.3.
Of 12,707 patients identified in the database, 7,923 met the eligibility criteria:
- N2018: 4,561 patients
- A2018: 3,362 patients
The treatment trends are summarized in Table 1 and Figure 1 below. 1st line systemic therapy for the majority of patients transitioned from TKI monotherapy (79%) B2018 to PD-1 combination therapies A2018 (58%). TKI monotherapy remained the most common treatment in both groups in the post-1st line setting. In the B2018 cohort, 58% of patients received 2nd line therapy, and 32% received 3rd line therapy. In the A2018 cohort, 42% and 16% received 2nd and 3rd line therapies, respectively.
In the B2018 cohort, 59% of patients received next treatment, 31% died without further therapy, and 10% were alive without therapy. Correspondingly, in the A2018 cohort, 52% of patients received next therapy, 35% died without further therapy, and 13% were alive without treatment (Table 2).
Dr. Galarza Fortuna concluded as follows:
- Despite the increased utilization of PD-1-based combination regimens since 2018, a significant number of patients did not receive novel combination regimens in the 1st line metastatic ccRCC setting in a real-world US population.
- With the uptake of PD-1-based combinations in the 1st line setting, a higher proportion of patients experienced treatment-free intervals or were alive without further therapy at 1-year attrition rate analysis after 1st line treatment discontinuation.
- These findings require validation in other datasets and can help patient counseling in the clinical setting.
Presented by: Gliceida Galarza Fortuna, MD, Hematology and Medical Oncology Fellow, Huntsman Cancer Institute at the University of Utah, Salt Lake City, UT
Written by: Rashid Sayyid, MD, MSc – Society of Urologic Oncology (SUO) Clinical Fellow at The University of Toronto, @rksayyid on Twitter during the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting, Chicago, IL, Fri, May 31 – Tues, June 4, 2024.