Maintenance durvalumab, the standard-of-care treatment for patients with unresectable stage III non–small cell lung cancer (NSCLC), remains significantly underutilized, according to data presented at the International Association for the Study of Lung Cancer (IASLC) 2021 World Conference on Lung Cancer.1
Analyses conducted in both open claims and adjudicated closed claims showed that less than 23% and 36% of patients with NSCLC, respectively, received the anti–PD-1 inhibitor durvalumab, despite its approval by the U.S. Food and Drug Administration (FDA) in 2018. Conversely, the rates of no maintenance therapy (30%) and maintenance pembrolizumab (25%) were found to be “higher than expected,” said lead study author Jason Liu, MD, of City of Hope National Medical Center, Duarte, California.
Jason Liu, MD
“This study raises questions as to why some providers might choose pembrolizumab over durvalumab,” said Dr. Liu. “Increasing the utilization of maintenance durvalumab would likely result in improved oncologic outcomes.”
Durvalumab was approved by the FDA based on the results of the PACIFIC trial, which showed a 13% improvement in overall survival and a 16% improvement in progression-free survival vs placebo in patients with unresectable stage III NSCLC whose disease had not progressed following concurrent platinum-based chemotherapy and radiation therapy.2 The current standard of care for unresectable stage III NSCLC is 6 weeks of chemotherapy followed by 1 year of maintenance durvalumab.
For this retrospective study, Dr. Liu and colleagues analyzed open claims using IQVIA pharmacy and medical claims data and adjudicated closed claims from IQVIA PharMetrics Plus Health Plan Claims Database. IQVIA currently captures approximately 67% of all pharmacy claims in the Surveillance, Epidemiology, and End Results (SEER) Program, according to Dr. Liu.
The researchers included patients with a lung cancer diagnosis between November 2017 and November 2020 and retained patients with any advanced or metastatic cancer codes. Patients with small cell lung cancer were excluded from the analysis, whereas those who received 6 weeks of chemoradiation after the index date and prior to May 31, 2020, were retained.
High Rates of No Maintenance Therapy
Of the 8,071 patients with NSCLC included in the analysis using open claims, just 1,794 (22.2%) received maintenance durvalumab. Conversely, 34.5% and 25.4% of patients received maintenance chemotherapy and maintenance pembrolizumab, respectively, and 34.9% of patients received no maintenance therapy, Dr. Liu reported.
The rate of durvalumab utilization was higher among the 357 patients included from closed claims date, but it was still just 35.6% of patients, said Dr. Liu. Analysis of closed claims showed a similarly high percentage of patients received maintenance chemotherapy (34.7%), maintenance pembrolizumab (23.0%), and no maintenance therapy (20.2%).
Although the rate of maintenance durvalumab utilization was low in both the open and closed claims data source, Dr. Liu acknowledged that the absolute rate may not be totally reliable, since the analysis was unable to exclude patients who had contraindications to durvalumab or disease progression after chemoradiation.
DISCLOSURE: Dr. Liu reported no conflicts of interest.
REFERENCES
1. Liu J: Patterns of care in maintenance therapy in U.S. patients undergoing definitive chemoradiation for stage 3 non-small cell lung cancer. IASLC 2021 World Conference on Lung Cancer. Abstract MA06.05. Presented September 9, 2021.
2. Faivre-Finn C, Vicente D, Kurata T, et al: Four-year survival with durvalumab after chemoradiotherapy in stage III NSCLC. J Thorac Oncol 16:860-867, 2021.