Abstract P5-08-18: Treatment patterns and resource utilization among patients with HR+/HER2– metastatic breast cancer in a privately insured US population
Authors: Goyal RK , Carter GC , Nagar SN , Smyth EN , Price GL , Huang Y-J , Bromund JL , Li L , Schilder JM , Davis KL , Kaye JA 
Published: March 2017

Abstract
Background
Hormone receptor positive (HR+)/HER2– tumors are the most common subtype among patients with metastatic breast cancer (MBC). Several newer therapeutic options have become available over the last decade, but little is known about the real-world treatment patterns and health care resource use (HCRU) in privately insured women with HR+/HER2– MBC.
Methods
An analysis of Truven MarketScan databases containing medical and drug utilization and productivity data from nearly 350 US payers was conducted. Patients aged 18-64 years with an ICD-9 diagnosis code of breast cancer along with ≥2 claims for secondary malignancy between 2007 and 2013 were selected. HR+/HER2– patients were identified based on receipt of endocrine therapy (ET) and absence of HER2-targeted therapies. Use of cancer-directed treatments following MBC diagnosis was analyzed. Treatment characteristics were examined by line of therapy (LOT). Average monthly all-cause and MBC-related HCRU were descriptively assessed.
Results
A total of 5,563 women with HR+/HER2– MBC (mean [SD] age, 54 [7.8] yrs) met the selection criteria. Overall, 97% of the total sample received ≥1 cancer-directed treatment. The most common treatment was ET (85%), followed by chemotherapy (CT) (70%), radiation (62%), and surgery (11%). Treatment patterns for CT alone and ET alone, including the top regimens by LOT, are presented in Table 1. Among those receiving a second LOT, nearly 44% switched to CT in the second line after having received ET alone in the first line. During the study follow-up, 56% of patients had ≥1 all-cause inpatient admission, 49% had ≥1 all-cause emergency department visit, and 9% had a hospice admission.
Table 1. Treatment patterns by LOT in patients with HR+/HER2- MBCLine 1 Line 2 Line 3 Line 4 n=5,179 (93%)* n=2,900 (52%)* n=1,608 (29%)* n=882 (16%)* n (%) n (%) n (%) n (%)ET Alone3265 (63)ET Alone1468 (51)ET Alone534 (33)ET Alone217 (25)Anastrozole895 (27)Fulvestrant354 (24)Fulvestrant138 (26)Fulvestrant65 (30)Letrozole782 (24)Tamoxifen258 (18)Exemestane89 (17)Exemestane44 (20)Tamoxifen577 (18)Exemestane239 (16)Letrozole82 (15)Tamoxifen25 (12)Fulvestrant428 (13)Anastrozole239 (16)Tamoxifen82 (15)Letrozole20 (9)Exemestane299 (9)Letrozole197 (13)Anastrozole65 (12)Anastrozole14 (6)CT Alone1533 (30)CT Alone1057 (36)CT Alone818 (51)CT Alone505 (57)Paclitaxel413 (27)Capecitabine331 (31)Capecitabine265 (32)Capecitabine140 (28)Capecitabine286 (19)Paclitaxel224 (21)Paclitaxel156 (19)Paclitaxel93 (18)Cyclophosphamide-Doxorubicin → Taxane93 (6)Gemcitabine63 (6)Gemcitabine70 (9)Vinorelbine55 (11)Cyclophosphamide-Docetaxel82 (5)Docetaxel46 (4)Vinorelbine54 (7)Gemcitabine52 (10)Carboplatin-Paclitaxel77 (5)Vinorelbine46 (4)Doxorubicin45 (6)Doxorubicin34 (7)*Out of total 5,563 patients. Only top CT and ET regimens are listed.
Conclusions
A substantial decrease in the use of ET, with simultaneous increase in the use of CT, was observed as patients progressed to subsequent LOTs. Nearly half of those receiving ET alone in the first LOT switched to CT in the second LOT, suggesting a need for more effective non-CT treatments to bridge unmet therapeutic needs in this patient population.
Citation Format: Goyal RK, Carter GC, Nagar SN, Smyth EN, Price GL, Huang Y-J, Bromund JL, Li L, Schilder JM, Davis KL, Kaye JA. Treatment patterns and resource utilization among patients with HR+/HER2– metastatic breast cancer in a privately insured US population [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-08-18.