Importance: Gemcitabine-nab-paclitaxel (GEMNAB) and fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) both improve survival of patients with advanced pancreatic cancer when compared with single-agent gemcitabine in clinical trials.
Objective: To describe changes in the survival of patients with advanced pancreatic cancer associated with sequential drug-funding approvals and to determine if there exist distinct patient populations for whom GEMNAB and FOLFIRINOX are associated with survival benefit.
Design, setting, and participants: This population-based, retrospective cohort study examined all incident cases of advanced pancreatic cancer treated with first-line chemotherapy in Ontario, Canada (2008-2018) that were identified from the Cancer Care Ontario (Ontario Health) New Drug Funding Program database. Statistical analysis was performed from October 2020 to January 2021.
Exposures: First-line chemotherapy for advanced pancreatic cancer.
Main outcomes and measures: The main outcomes were the proportion of patients treated with each chemotherapy regimen over time and overall survival for each regimen. Cox proportional hazards regression models were used to compare overall survival between treatment regimens after adjustment for confounding variables, inverse probability of treatment weighting, and matching.
Results: From 2008 to 2018, 5465 patients with advanced pancreatic cancer were treated with first-line chemotherapy in Ontario, Canada. The median (range) age of patients was 66.9 (27.8-93.4) years; 2447 (45%) were female; 878 (16%) had prior pancreatic resection, and 328 (6%) had prior adjuvant gemcitabine. During the time period when only gemcitabine and FOLFIRINOX were funded (2011-2015), 49% (929 of 1887) received FOLFIRINOX. When GEMNAB was subsequently funded (2015-2018), 9% (206 of 2347) received gemcitabine, 44% (1034 of 2347) received FOLFIRINOX, and 47% (1107 of 2347) received GEMNAB. The median overall survival increased from 5.6 months (95% CI, 5.1-6.0 months) in 2008 to 2011 to 6.9 months (95% CI, 6.5-7.4 months) in 2011 to 2015 to 7.6 months (95% CI, 7.1-8.0 months) in 2015 to 2018. Patients receiving FOLFIRINOX were younger and healthier than patients receiving GEMNAB. After adjustment and weighting, FOLFIRINOX was associated with better overall survival than GEMNAB (hazard ratio [HR], 0.75 [95% CI, 0.69-0.81]). In analyses comparing patients treated with GEMNAB and gemcitabine, GEMNAB was associated with better overall survival (HR, 0.86 [95% CI, 0.78-0.94]).
Conclusions and relevance: This cohort study of patients with advanced pancreatic cancer receiving first-line palliative chemotherapy within a universal health care system found that drug funding decisions were associated with increased uptake of new treatment options over time and improved survival. Both FOLFIRINOX and GEMNAB were associated with survival benefits in distinct patient populations.