Maintenance durvalumab—the recommended maintenance treatment for patients with unresectable stage III non–small cell lung cancer (NSCLC) following chemoradiation—remains significantly underutilized, according to research presented by Liu et al at the International Association for the Study of Lung Cancer (IASLC) 2021 World Conference on Lung Cancer (Abstract MA06.05).

An analysis of insurance claims data found that less than 23% of patients with NSCLC received the anti–PD-1 inhibitor durvalumab, despite its approval by the U.S. Food and Drug Administration (FDA) in 2018. Conversely, rates of no maintenance therapy (30%) and maintenance pembrolizumab (25%) were shown to be “higher than expected,” said lead study author Jason Liu, MD, of City of Hope National Medical Center, in Duarte, California.

“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 for by the FDA based on 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. The current standard of care treatment for unresectable stage III NSCLC is 6 weeks of chemotherapy followed by 1 year of maintenance durvalumab.

Analysis Details

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 covers approximately 90% of dispensed prescriptions in the United States, Dr. Liu reported.  

The researchers included patients with a lung cancer diagnosis between November of 2017 and November of 2020 and retained patients with any advanced or metastatic cancer codes. Patients with small cell lung cancer were excluded from the analysis, while those who received 6 weeks of chemoradiation after the index date and prior to May 31, 2020, were retained.

Of the 8,071 patients with NSCLC included in the analysis using open claims, only 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 was still only 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 reliable since the analysis was unable to exclude patients who had contraindications to durvalumab or disease progression after chemoradiation.

“Therefore, we recommend future studies to better understand these current practice patterns in the United States,” Dr. Liu concluded.

Disclosure: Dr. Liu had no relevant financial disclosures.