title: Identifying Subsequent Therapies in Patients with Advanced Non-Small Cell Lung Cancer and Factors Associated with Overall Survival.
abstract: To identify subsequent therapies used after first-line therapies in patients with advanced non-small cell lung cancer (NSCLC), compare overall survival (OS) associated with subsequent therapies, and evaluate factors associated with OS in these patients.
  
  
  
  The study was a retrospective cohort analysis of patients with advanced NSCLC (stage IIIB/IV) who were initiated on first-line therapy from January 1, 2008, through September 30, 2013, and afterward given subsequent chemotherapy (index date). Patients had to be 18 years or older at the time of diagnosis of advanced NSCLC. Patients were followed from the index date until one of the following end points: end of the study (September 30, 2014), disenrollment from the health plan, or death-whichever came the earliest. The primary outcome was OS. Kaplan-Meier curves and Cox proportional hazard models were used to analyze OS and evaluate the factors associated with OS.
  
  
  
  The analysis included 1280 patients on subsequent therapies. The most common subsequent therapies were pemetrexed (284 patients [22%]), erlotinib (216 patients [17%]), and docetaxel (139 patients [11%]). Patients from the singlets group had a lower OS at 6.3 months compared with all other groups: pemetrexed based, combination of pemetrexed and bevacizumab based, bevacizumab based, doublets, and tyrosine kinase inhibitors (p<0.0001). Factors associated with greater OS included age younger than 65 years, female gender, and a longer time between initiation of first and subsequent therapies. Factors associated with a reduction in OS were pemetrexed-based or singlet regimens for subsequent therapy, diagnosis of squamous histology, and a higher number of adverse events prior to subsequent therapy.
  
  
  
  We found that a subsequent therapy consisting of singlets is associated with reduced OS compared with other chemotherapy groups. Patient characteristics such as female gender, age younger than 65 years, diagnosis of nonsquamous histology, and/or a longer time frame between initiation of first-line and subsequent chemotherapy are associated with longer survival.
authors: Drug Information Group, University of Illinois-Chicago, College of Pharmacy, Chicago, Illinois. afana@uic.edu.|Drug Information Services, Kaiser Permanente, Oakland, California. afana@uic.edu.
authors: Janna
authors: J
authors: Afanasjeva
authors: Pharmacy Outcomes Research Group, Kaiser Permanente, Oakland, California.
authors: Rita L
authors: RL
authors: Hui
authors: Pharmacy Outcomes Research Group, Kaiser Permanente, Oakland, California.
authors: Michele M
authors: MM
authors: Spence
authors: Drug Information Services, Kaiser Permanente, Oakland, California.
authors: Jennifer
authors: J
authors: Chang
authors: Southern California Kaiser Permanente Medical Group, Pasadena, California.
authors: Joanne E
authors: JE
authors: Schottinger
authors: Drug Information Services, Kaiser Permanente, Oakland, California.
authors: Mirta
authors: M
authors: Millares
authors: Pharmacy Outcomes Research Group, Kaiser Permanente, Oakland, California.
authors: Nazia
authors: N
authors: Rashid
mesh_terms: D000367:Age Factors; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000473:pathology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012737:Sex Factors; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome
keywords: non-small cell lung cancer; outcomes research; overall survival; subsequent therapy