FORT WORTH, Texas — Patients with non-small cell lung cancer exposed to immunotherapy as second-line treatment achieved clinically meaningful PFS after receiving chemotherapy in the third-line setting, according to study results presented at HOPA Ahead 2019.
Alexis E. DeLeo, PharmD, PGY2 oncology pharmacy resident at Allegheny General Hospital, and colleagues observed no statistically significant different in outcomes based on the third-line regimen chosen. However, results showed a trend toward improved PFS and OS with platinum therapy in the third-line setting.
“Several studies have reported on use of immunotherapy agents for treatment of non-small cell lung cancer, but there was a gap in the literature regarding what happens after patients receive immunotherapy and how they were doing with further lines of treatment,” DeLeo told HemOnc Today.
DeLeo and colleagues conducted a retrospective chart review of 43 patients (median age, 67 years; 23 men) with relapsed or refractory NSCLC who received immunotherapy with nivolumab (Opdivo, Bristol-Myers Squibb), pembrolizumab (Keytruda, Merck) or atezolizumab (Tecentriq, Genentech) in the second-line setting and went on to receive cytotoxic chemotherapy in the third-line setting. Patients who were enrolled in a clinical trial or who received immunotherapy in the first-line setting were excluded.
Forty-two patients (97.7%) reported current or prior tobacco use and 10 (23.3%) had brain metastases at diagnosis. The most common third-line chemotherapy regimens included docetaxel (58.1%), platinum (18.6%), gemcitabine (7%) or pemetrexed (7%). Other regimens included albumin-bound paclitaxel, vinorelbine, topotecan and osimertinib (Tagrisso, AstraZeneca).
Thirty-three patients (76.7%) experienced progression or died during the study period.
In the entire cohort, median PFS was 149 days (95% CI, 74.9-223) and median OS was 442 days (95% CI, 174.9-709).
An analysis of outcomes based on type of third-line chemotherapy showed patients treated with a platinum regimen achieved longer median PFS (242 days vs. 117 days with docetaxel and 149 for other regimens) and median PFS (625 days vs. 442 days with docetaxel and 452 days with other regimens), but these differences did not reach statistical significance.
“We were hoping to find a third-line regimen that could potentially be more appropriate for these patients,” DeLeo said. “Unfortunately, we were unable to power it to any sort of significance based on the patient population we were able to include.”
Re-exposure to platinum did not cause any adverse events that would require desensitization, DeLeo said.
DeLeo and colleagues also determined results of their study were comparable to previously published findings of other third- and fourth-line regimens, including erlotinib (Tarceva; Genentech, Astellas) and irinotecan.
“This has called into question whether we should be re-exposing to platinum,” she said. “Those patients seemed to do really well in the third line. This is not something necessarily recommended in the guidelines but you never know if it could be clinically meaningful for a patient.”
Expanding this work to include patients with NSCLC who received immunotherapy in the first-line setting could provide additional insights and potentially provide the power necessary to achieve statistical significance, DeLeo said. – by Mark Leiser
Reference: DeLeo A, et al. Quantification of progression-free survival in non-small cell lung cancer patients receiving chemotherapy in the third-line setting previously exposed to immunotherapy. Presented at: HOPA Ahead 2019; April 3-6, 2019; Fort Worth, Texas.
Disclosures: DeLeo reports no relevant financial disclosures. Another author reports honoraria from Bristol-Myers Squibb.