Aim: Describe hairy cell leukemia (HCL) treatment patterns using a large, nationally representative US database. Patients & methods: Adults newly diagnosed with HCL (1 January 2006 to 30 June 2014) with continuous health plan enrollment ≥180 days pre- and 90 days post-diagnosis were identified from the QuintilesIMS PharMetrics Plus Health Plan Claims Database. Treatment patterns by line of therapy were assessed over the variable follow-up. Results: Among 749 HCL patients (77.4% male; mean age 55.6; mean 32.3 months follow-up), only 37.7% initiated first-line therapy during the available follow-up in a mean of 4.4 months following diagnosis; the majority (75.5%) received cladribine (mean duration 7.3 days). Thirty-eight patients (5.1%) received second-line treatment. Conclusion: Over 2.7 years follow-up, more than a third of patients initiated first-line therapy which appeared to provide a long-lasting response.

Background and Objective : Hairy cell leukemia (HCL) is an uncommon condition with an estimated 900 incident cases annually and accounts for approximately 2% of all leukemia cases in the United States. Purine analogs including cladribine and pentostatin are the two agents of choice in managing patients with HCL. Limited information exists with regard to costs associated with the management of patients with HCL. Thus, this study evaluated real-world all-cause and HCL-related healthcare utilization and costs among patients with HCL. Methods : A retrospective observational study was conducted using the IMS Health PharMetrics Plus Health Plan Claims Database for the period 2006-2014. The database includes over 150 million unique health plan members across the US and is nationally representative of the commercially-insured US population. Database includes medical and outpatient pharmacy claims for individuals enrolled in managed care health plans. Information on charged and paid amounts along with co-pay information is included in claim records. Additionally, claim records include details on, but not limited to, diagnoses, procedures, date of service, and discharge date (inpatient visit). Adult (≥18 years of age) patients with at least two claims with a diagnosis of HCL (ICD-9-CM code: 202.4x) were selected and the first observed claim defined the "index date." Patients with evidence of other malignancies (identified using relevant ICD-9-CM codes) during the 6-month prior (pre-index period) to the index date were excluded. Patients were required to have at least 90 days of continuous enrollment (the variable "follow-up" period) in the health plan post index date with exception of patients who died within 3 months of diagnosis. Patients were followed until death (recorded on inpatient discharge disposition) or until the end of database. Study measures including baseline costs (pre-index period) and follow-up period all-cause and HCL-related (assessed based on presence of HCL diagnosis code and/or HCL-associated therapies) utilization and costs were evaluated on a per-patient basis. Annualized healthcare utilization and costs were also estimated [(annualized rate of use/costs = (units used or costs post-index)/(days follow-up post-index/365)]. All analyses were descriptive in nature with continuous measures (e.g., HCL-related inpatient costs) measures presented using mean, median, standard deviation (SD) and categorical measures (e.g., patient with a HCL-related inpatient admission) using frequency and percentages. Cost analyses were conducted from a payer perspective (i.e., paid amounts [not charged amounts] were used in cost estimation). Results : The study cohort included 749 patients with mean (SD) post-diagnosis follow-up of 32 (22) months. Over 3/4th of patients were males (77%) and the mean age (SD) at diagnosis was 56 (10) years. The mean pre-index per patient costs for the study cohort was $5,858 ($13,836). Slightly more than a third (38%) of patients initiated first-line chemotherapy over the available follow-up, and pre-index costs were higher among patients initiating chemotherapy compared with to those who did not initiate chemotherapy ($6,635 [$7,246] vs. $5,389 [$16,584]). 36% of patients had at least 1 HCL-related inpatient admission and over 95% had at least 1 HCL-related physician office visit during the follow-up period. The average follow-up period all-cause costs were $55,904 of which 50% were related to outpatient care, 40% related to inpatient care and 9% related to outpatient pharmacy costs. The mean annualized all-cause costs were $50,585 of which over 65% (mean: $33,111) attributed to inpatient costs. The follow-up period HCL-related total costs were $31,234 of which HCL-related inpatient costs accounted for 55% and 44% were attributed to HCL-related outpatient care. The mean annualized HCL-related costs were $38,588 with the vast majority (81%) attributed to inpatient costs. Conclusion : The current study provides real-world all-cause and HCL costs estimates from a payer perspective among patients with HCL. With newer therapies being developed for HCL, findings from this study can serve as inputs in the development of cost-effectiveness models comparing new and existing treatments. Disclosures Divino: IMS Health: Employment, Other: IMS Health received funding from AstraZeneca for this study. Karve:AstraZeneca: Employment. Gaughan:AstraZeneca: Employment. DeKoven:IMS Health: Employment, Other: IMS Health received funding from AstraZeneca for this study. Gao:MedImmune: Employment. Lanasa:MedImmune: Employment.

Background and Objective : Hairy cell leukemia (HCL) is a rare condition and accounts for ~2% of all leukemia cases in the US. NCCN guidelines recommend first-line agents including pentostatin and cladribine among patients with HCL. However, a paucity of data exists with regard to real-world treatment patterns among patients with HCL. Current study evaluates treatment patterns and associated clinical outcomes among patients with HCL using a large US administrative claims database. Methods : This retrospective observational study was conducted using the IMS Health PharMetrics Plus Health Plan Claims Database (2006-2014), which includes over 150 million unique health plan members across the US and is nationally representative of the commercially-insured US population. Data includes date stamped medical and pharmacy records along with information on health plan enrollment. Individuals with at least 2 medical claims with a diagnosis for HCL (identified using ICD-9-CM cod: 202.4x) were selected and the first observed claim defined the "index date." Patients <18 years of age at index date or with other malignancies during 6 months (the "pre-index period") prior to index date were excluded. Patients were required at least 90 days of continuous enrollment (the variable "follow-up period") in the health plan post index date with exception of patients who died within 3 months of diagnosis. Patients were followed until death (recorded on inpatient discharge disposition), end of enrollment or end of database, whichever occurred earlier. Study measures including patient demographic and baseline clinical characteristics, line of therapy (LOT), treatment patterns, relapse (receipt of same or new regimen in subsequent LOT following a gap of 365 days) and refractory disease (receipt of same or new regimen where the gap of two adjacent LOTs was <365 days) and post-treatment complications were assessed during the follow-up period. All analyses were descriptive in nature. Results : The study cohort included 749 patients after applying the selection criteria (mean follow-up from diagnosis 32 months). At diagnosis, the mean age (standard deviation) of the study cohort was 56 (10) years and majority of patients were male (77%). Mean baseline comorbidity burden (assessed using Charlson Comorbidity Index score) was 0.8 (1.1) with hypertension (24%) and aplastic anemia (22%) being the two most common co-morbidities. Only 38% (n=282) of patients received first-line chemotherapy post diagnosis. Majority initiated first-line cladribine (76%) as a single agent, while 9% had evidence of single agent pentostatin. Mean time to initiation of first-line therapy from diagnosis was 132 (294) days and average time on first-line therapy was 34 (104) days. Among patients with first-line therapy 14% received second-line therapy and rituximab (53%) and cladribine (21%) were frequently observed second-line agents. Post first-line therapy, mean time to initiation of second-line therapy was 303 (406) days. Among second-line initiators, 76% had refractory disease and 24% had relapsed following first-line. Neutropenia and fever were frequently reported complications while on chemotherapy. Conclusion : The real-world chemotherapy utilization patterns observed in this study are consistent with the NCCN guidelines with cladribine and pentostatin being the agents of choice for first-line therapy. Following diagnosis, more than one-third of patients initiated chemotherapy and only a small proportion of these received second-line chemotherapy suggesting durable response with first-line therapy. Limited follow-up post first-line therapy may have impacted the proportion of patients initiating second-line therapy as well as categorization of refractory and relapse disease. Disclosures Karve: AstraZeneca: Employment. Divino:IMS Health: Employment, Other: IMS Health received funding from AstraZeneca for this study. Gaughan:AstraZeneca: Employment. DeKoven:IMS Health: Employment, Other: IMS Health received funding from AstraZeneca for this study. Gao:MedImmune: Employment. Lanasa:MedImmune: Employment.