EGFR mutation testing and TKI treatment patterns among veterans with stage III and IV non-small cell lung cancer.

BACKGROUND: Epidermal growth factor receptor (EGFR) mutation testing is recommended in metastatic non-small cell lung cancer (NSCLC). The objective of this study was to assess changes in EGFR mutation testing patterns and tyrosine kinase inhibitor (TKI) use in US veterans with stage III-IV NSCLC between 2013 and 2017. PATIENTS AND METHODS: Retrospective study using linked data from Department of Veterans Affairs (VA) Cancer Registry System, Corporate Data Warehouse, commercial laboratories, and clinical notes. Generalized linear mixed models accounting for clustering by VA facility were used to determine factors associated with EGFR mutation testing. RESULTS: From 2013 to 2017, EGFR mutation testing increased from 29.5% to 38.4% among veterans with stage III-IV NSCLC and from 47.0% to 57.4% among veterans with stage IV non-squamous disease. Factors associated with increased odds of testing included being married, Medicare enrollment, and adenocarcinoma histology. Factors associated with decreased odds of testing included Medicaid eligibility, stage III disease, increasing age, being a current or former smoker, increasing Charlson-Deyo comorbidity score, and receiving cancer care in the South. Appropriate use of a TKI rose from 2013 to 2017 (17.2% to 74.1%). CONCLUSION: EGFR mutation testing rates increased to almost 60% in the stage IV non-squamous NSCLC population in 2017, with residual opportunity for further increase. Several sociodemographic characteristics, comorbidities, and geographic regions were associated with EGFR mutation testing suggestive of inequitable testing decisions. Appropriate use of TKI improved drastically from 2013 to 2017 demonstrating rapidly changing practice patterns through the adoption phase of new treatment options.

Real-world impact of brain metastases on healthcare utilization and costs in patients with non-small cell lung cancer treated with EGFR-TKIs in the US.

BACKGROUND: Non-small cell lung cancer (NSCLC) with brain metastases (BM) is difficult to treat and associated with poor survival. This study assessed the impact of BM on healthcare-related utilization and costs (HRUC) among patients receiving epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). PATIENTS AND METHODS: Adults newly-diagnosed with metastatic NSCLC, initiating first-/second-generation EGFR-TKI treatment, with BM or no BM (NBM), were identified retrospectively from IBM MarketScan healthcare claims databases (2013-2017). HRUC were measured during the variable-length follow-up period. Generalized linear models assessed the impact of BM on total healthcare costs, standardized to 2017 US$. RESULTS: Overall, 222 BM and 280 NBM patients were included, with a mean duration of follow-up of 14 months. Adjusted NSCLC-related and all-cause costs over average follow-up were 1.2 times higher among BM patients (Δ$5,640 and Δ$6,366, respectively; p <0.05); differences were driven primarily by radiation treatment and radiology. More than two times more BM than NBM patients received NSCLC-related radiation treatment, in both inpatient (15.3% vs 6.8%; p <0.05) and outpatient settings (87.8% vs 37.5%; p <0.05). Per-patient per-month (PPPM) radiation costs were also higher among BM patients, both inpatient ($796 vs $464, p =0.172) and outpatient ($2,443 vs $747, p <0.05). All-cause PPPM radiology visits (2.0 vs 1.3) and associated costs ($3,824 vs $1,621) were higher among BM patients (both p <0.05). CONCLUSION: NSCLC-related HRUC, especially those attributable to radiation treatment, were higher among patients with BM. Future research should compare the potential for CNS-active EGFR-TKIs vs first-/second-generation EGFR-TKIs combined with radiotherapy to reduce HRUC.

Real-world disease burden and outcomes of brain metastases in EGFR mutation-positive non-small-cell lung cancer.

Aim: To evaluate the real-world impact of brain metastases (BM) among patients with EGFR mutation-positive (EGFRm) metastatic non-small-cell lung cancer (NSCLC). Materials & methods: This retrospective, observational matched cohort electronic health record study assessed adults with EGFRm metastatic NSCLC with/without BM. Results: Among 402 patients split equally between both cohorts (±BM), the majority were Caucasian (69%), female (65%) and with adenocarcinoma (92%). Overall symptom burden and ancillary support service use were higher and median overall survival from metastatic diagnosis was significantly shorter in BM patients (11.9 vs 16 months; p = 0.017). Conclusion: BM in EGFRm NSCLC patients can negatively impact clinical outcomes. New targeted therapies that can penetrate the blood-brain barrier should be considered for treating these patients.

EGFR mutation testing and treatment decisions in patients progressing on first- or second-generation epidermal growth factor receptor tyrosine kinase inhibitors.

BACKGROUND: The objective of this study was to investigate real-world EGFR mutation testing in patients with metastatic non-small cell lung cancer (NSCLC) upon progression on first-/second-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI), and subsequent treatments received. METHODS: Flatiron Health electronic health records-derived database was used to identify adult patients with metastatic NSCLC treated with first-/second-generation EGFR-TKI from 11/2015-09/2017, with start of first EGFR-TKI defined as the index date. Patients were stratified by receipt of EGFR-TKI as first-line (1 L) or later-line (2 L+) treatment. Mutation testing and subsequent therapies following first-/second-generation EGFR-TKI were described. RESULTS: Overall, 782 patients (1 L = 435; 2 L+ =347) were included. Median age was 69.0 years, 63.6% were female, 56.3% were white, 87.1% were treated in community-based practices, and 30.1% of patients died during the study period; median follow-up was 309.0 days. Among the 294 (1 L = 160; 2L+ =134) patients who received subsequent therapies, treatments included chemotherapy only (1 L = 15.6%; 2L+ =21.6%), immunotherapy only (1 L = 13.8%; 2 L+ =41.0%), and targeted therapies (1 L = 70.0%; 2 L+ =36.6%). Specifically, 40 (25.0%) 1 L patients and 7 (5.2%) 2 L+ patients received osimertinib as subsequent therapy. Before the start of subsequent therapy, EGFR T790M resistance mutation testing was performed in 88 (29.9%) patients (1 L = 63 [39.4%]; 2 L+ =25 [18.7%]). Of these patients, 25 (28.4%) were T790M positive, among whom 24 (96.0%) received osimertinib. CONCLUSIONS: A third of patients received subsequent therapies on disease progression; only 30% of these were tested for EGFR-TKI resistance mutation, prior to receiving subsequent therapies. These results highlight the importance of choosing treatments in the 1 L setting that optimize benefits for patients with EGFR-mutated NSCLC.

Adverse event rates and economic burden associated with purine nucleoside analogs in patients with hairy cell leukemia: a US population-retrospective claims analysis.

BACKGROUND: Purine nucleoside analogs (PNAs) are the recommended first-line treatment for patients with hairy cell leukemia (HCL), but they are associated with adverse events (AEs). Due to a lack of real-world evidence regarding AEs that are associated with PNAs, we used commercial data to assess AE rates, AE-related health care resource utilization (HCRU), and costs among PNA-treated patients with HCL. Adults aged ≥18 years with ≥2 claims for HCL ≥30 days apart from 1 January 2006 through 31 December 2015 were included. Included patients had ≥1 claim for HCL therapy (cladribine ± rituximab or pentostatin ± rituximab [index date: first claim date]) and continuous enrollment for a ≥ 6-month baseline and ≥ 12-month follow-up period. Patient sub-cohorts were based on the occurrence of myelosuppression and opportunistic infections (OIs). Generalized linear models were used to compare HCRU and costs. RESULTS: In total, 647 PNA-treated patients were identified (mean age: 57.1 years). Myelosuppression and OI incidence were 461 and 42 per 1000 patient-years, respectively. Adjusted results indicated that those with myelosuppression had higher rates of hospitalization (47.4% vs 12.4%; P < .0001) and incurred higher mean inpatient costs ($23,517 vs $12,729; P = .011) and total costs ($57,325 vs $34,733; P = .001) as compared with those without myelosuppression. Similarly, patients with OIs had higher rates of hospitalization (53.8% vs 30.8%; P = .025) and incurred higher mean inpatient costs ($21,494 vs $11,229; P < .0001) as compared with those without OIs. CONCLUSIONS: PNA therapy is highly effective but associated with significant toxicities that increase costs; these findings indicate a need for therapies with improved toxicity profiles and better risk stratification of patients at risk of developing myelosuppression and OIs.

Observational Study of Treatment Patterns in Patients with Epidermal Growth Factor Receptor (EGFR) Mutation-Positive Non-Small Cell Lung Cancer After First-Line EGFR-Tyrosine Kinase Inhibitors.

INTRODUCTION: Epidermal growth factor receptor (EGFR) mutations are observed in approximately 15% of patients with non-small cell lung cancer (NSCLC) in the USA. Little is known about treatment patterns in EGFR mutation-positive NSCLC following progression on or after first-line (1L) treatment with first- or second-generation EGFR tyrosine kinase inhibitors (EGFR-TKIs). Osimertinib, a third-generation EGFR-TKI, is a treatment option for patients with EGFR T790M-positive NSCLC following progression on 1L EGFR-TKIs. This study analyzed real-world treatment sequencing of EGFR-TKIs, EGFR T790M testing rates, and disposition of patients with EGFR mutations after 1L EGFR-TKI post-FDA approval of osimertinib in patients with EGFR mutation-positive NSCLC. METHODS: Adult patients with stage IV NSCLC and documented EGFR mutation-positive status were identified between December 1, 2015 and May 31, 2017 from the US Oncology Network iKnowMed™ electronic health record (EHR). Data were abstracted from the EHR database and supplemented by chart review. RESULTS: Of 308 patients, 302 (98%) received an EGFR-TKI overall, and 246 patients (80%) received a 1L EGFR-TKI. The most common 1L EGFR-TKI was erlotinib (66%); the remaining 1L regimens were predominantly combination chemotherapies with or without an EGFR-TKI. Only 80 patients (26%) received any 2L therapy. The most common EGFR-TKIs used as 2L monotherapy in patients who received 1L EGFR-TKI were afatinib and osimertinib (n = 7 for both). Among all patients treated with 1L EGFR-TKI (n = 246), 47 (19%) were tested for EGFR T790M [16 patients (34%) were positive], 48 (20%) remained on 1L EGFR-TKI, 29 (12%) received subsequent therapy, 38 (15%) had died on or after their 1L EGFR-TKI therapy, and 131 (53%) stopped their EGFR-TKI with no recorded evidence of having received subsequent therapy at follow-up end. CONCLUSION: Following 1L EGFR-TKI treatment, 19% of patients were tested for EGFR T790M, and most (69%) had no record of receiving any subsequent therapy.

The rate of occurrence, healthcare resource use and costs of adverse events among metastatic non-small cell lung cancer patients treated with first- and second-generation epidermal growth factor receptor tyrosine kinase inhibitors.

OBJECTIVES: Clinical trials with first- and second-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) reported severe adverse events (SAEs) in 6%-49% of patients with EGFR-mutated non-small cell lung cancer. This study describes incremental healthcare resource utilization (HRU) and costs associated with real-world management of AEs in this population, with a focus on SAEs. MATERIALS AND METHODS: Patients receiving erlotinib, gefitinib, or afatinib as first-line (1L) monotherapy were identified from IQVIA™ Real-World Data Adjudicated Claims-US database (04/01/2012-03/31/2017). Relevant AEs were selected from corresponding prescribing information; SAEs were identified from hospitalization claims. HRU and cost per-patient-per-month (PPPM) were assessed during 1L treatment and compared for patients with and without each AE using multivariate Poisson and linear regression, respectively, adjusting for baseline characteristics. RESULTS: Of 1646 patients, 86.9% were treated with erlotinib, 12.1% with afatinib, and 1.0% with gefitinib. In 1L, 12.2% of patients had ≥1 acute SAE (220.1/1000 patient-years). Patients with any SAE had higher PPPM costs than patients without SAEs (cost difference = $4700, p < 0.001). Incremental costs ranged from $2604 PPPM for diarrhea to $10,143 PPPM for microangiopathic hemolytic anemia (MAHA), and were statistically significant for all SAEs (all p < 0.001) except MAHA (p < 0.0528). Patients with any SAEs had higher rates of HRU relative to patients without SAEs (hospitalization rate ratio = 6.15; outpatient visits rate ratio = 1.21; all p < 0.001). CONCLUSION: More than one-tenth of patients experienced SAEs, resulting in sizeable economic burden with respect to HRU and costs. EGFR-TKIs with more favorable safety profiles may reduce the burden of managing this population.

Patient preferences for attributes of tyrosine kinase inhibitor treatments for EGFR mutation-positive non-small-cell lung cancer.

Aim: EGFR-tyrosine kinase inhibitors (TKIs) vary in efficacy, side effects (SEs) and dosing regimen. We explored EGFR-TKI treatment attribute preferences in EGFR mutation-positive metastatic non-small-cell lung cancer. Materials & methods: Patients completed a survey utilizing preference elicitation methods: direct elicitation of four EGFR-TKI profiles describing progression-free survival (PFS), severe SE risk, administration; discrete choice experiment involving 12 choice tasks. Results: 90 participated. The preferred profile (selected 89% of times) had the longest PFS (18 months) and the lowest severe SE risk (5%). Patients would need compensation with ≥three-times longer PFS for severe SEs. Patients would accept ≤7 months PFS reduction for oral treatments versus intravenous. Conclusion: Patients preferred longer PFS but were willing to accept reduced PFS for more favorable SEs and dosing convenience.

Treatment patterns and overall survival among patients with unresectable, stage III non-small-cell lung cancer.

Aim: To analyze treatment patterns and overall survival (OS) across time (2009-2014) among patients with unresected, stage III non-small-cell lung cancer (NSCLC). Patients & methods: Stage III NSCLC patients aged ≥65 years who initiated therapy were identified using SEER-Medicare data. Results: Among 4564 patients, 84% received chemotherapy (with or without radiotherapy), and 59% received chemoradiotherapy (CRT). Carboplatin + paclitaxel was the most frequent regimen. Median (interquartile range) OS among chemotherapy patients was 13.2 (6.0-28.9) months, and 14.8 (6.7-33.4) months among CRT patients. Among CRT patients, there was no difference in OS across years of CRT initiation. Conclusion: OS remained static across 2009-2014, indicating stagnancy in clinical outcomes for stage III NSCLC patients and a need for more effective therapeutic options.

Real-world treatment patterns among patients with unresected stage III non-small-cell lung cancer.

Aim: Little is known about recent treatment patterns among patients with unresected stage III NSCLC in the real world. This retrospective study used medical records from USA community oncology practices to address this knowledge gap. Materials & methods: Eligible patients were stage III NSCLC adults diagnosed between 1 January 2011 and 1 March 2016 without surgical resection. Treatment patterns were assessed across three progression intervals, from stage III diagnosis through third progression. Results: The most common regimen in interval 1 was platinum doublet chemotherapy + radiation therapy, in interval 2 was chemotherapy only, and in interval 3 was non-platinum chemotherapy monotherapy. Conclusion: Most patients were treated following national guidelines, but important unmet needs remain.

Impact of Respiratory Syncytial Virus-Confirmed Hospitalizations on Caregivers of US Preterm Infants.

This study assessed the impact of respiratory syncytial virus-confirmed hospitalizations (RSVH) on caregivers of high-risk preterm infants. Caregivers for infants born at 29 to 35 weeks' gestational age and hospitalized for confirmed RSV disease responded to measures of self-rated and perceived infant stress (1-7; 7 = very stressful), perceived infant health (0-100; 100 = best imaginable health), and productivity impairment. Data were collected at hospital discharge through 1 month post-discharge. Caregiver responses indicated high stress levels, poor health, and productivity loss were reported at discharge; however, steady improvements were seen through 1 month post-discharge: caregiver-rated stress (from 6 to 2), infant stress (5 to 1), caregiver-perceived infant health (64 to 84), and productivity loss (mothers: 91% to 31%; fathers: 81% to 18%). Qualitative results indicated emotional impact, family routine disruption, financial concerns, and medical concerns persisted at 1 month post-discharge. This study found the caregiver burden of RSVH persists at least 1 month beyond discharge.

Real-world outcomes in patients with unresected stage III non-small cell lung cancer.

This study examined real-world clinical outcomes such as progression-free survival (PFS), time to metastasis (TTM), overall survival (OS), and health-related quality of life (HRQOL) in patients with unresected stage III non-small cell lung cancer (NSCLC) treated in the community setting. A retrospective review of medical records extracted from 10 US community oncology practices was conducted. Eligible patients were adults diagnosed with stage III NSCLC from 1/1/2011 to 3/1/2016 without evidence of surgical resection within 6 months after stage III NSCLC diagnosis (index date). PFS, OS, and TTM were assessed from the index date, and were analyzed using Kaplan-Meier and Cox regression analyses. HRQOL was assessed for a subset of patients using a patient-reported measure, the 86-item Patient Care Monitor (PCM). Linear mixed models (LMM) were used to assess the impact of patient characteristics and change in PCM scores associated with progression. Among the sample of 478 patients, median PFS (95% confidence interval) was 10 months (9-11), median OS was 20 months (17-22), and median TTM was 30 months (23-45). Most patients (58.2%) experienced disease progression, which the LMM showed to be associated with significant worsening of physical symptoms and psychological states (p < 0.001). This study documented PFS and OS consistent with published literature. The majority of patients experienced disease progression, which was associated with worsening of HRQOL. These findings highlighted the need for better therapeutic options in patients with unresected stage III NSCLC with potential to improve patient outcomes and HRQOL.

Treatment Patterns and Clinical Outcomes Among Metastatic Non-Small-Cell Lung Cancer Patients Treated in the Community Practice Setting.

INTRODUCTION: Multiple therapeutic options now exist for metastatic non-small-cell lung cancer (mNSCLC). In this study we evaluated treatment patterns and outcomes in mNSCLC patients who received first-line (1L), second-line (2L), and third-line (3L) therapy. PATIENTS AND METHODS: A retrospective, observational cohort study was conducted using an electronic health record database of mNSCLC patients who received initial treatment from January 2012 through April 2016, with follow-up through June 2016. Patient characteristics and treatment patterns were characterized. Overall survival (OS) was assessed using the Kaplan-Meier method. RESULTS: We identified 10,689 1L patients. Median age was 68 years, and 5816 (54%) were male. Most patients (6337; 59%) had a performance status of 1, and 8282 (77%) had nonsquamous histology. 1L treatment was chemotherapy in 9969 (93%) patients, and targeted therapy in 685 (6%). Median OS (mOS) for all patients in 1L was 12.3 months (95% confidence interval [CI], 11.9-12.7), and 24.3 months in 1L patients receiving targeted therapy. Among patients who received 2L therapy (n = 4235), 2790 (66%), 718 (17%), and 727 (17%) received chemotherapy, targeted therapy, and immunotherapy, respectively. mOS from 2L therapy was 9.6 months (95% CI, 9.1-10.1). In patients receiving 3L therapy (n = 1580), 921 (58%), 355 (22%), and 304 (19%) received chemotherapy, targeted therapy, and immunotherapy, respectively. mOS from 3L therapy was 8.2 months (95% CI, 7.3-8.7). CONCLUSION: Targeted therapy and immunotherapy was most frequently used in the 2L and 3L setting during the study time frame. Survival differences observed according to treatment types are likely because of biologic differences, and suggest that patients with actionable mutations have a survival advantage.

The 2014-2015 National Impact of the 2014 American Academy of Pediatrics Guidance for Respiratory Syncytial Virus Immunoprophylaxis on Preterm Infants Born in the United States.

OBJECTIVE: This article aims to compare respiratory syncytial virus (RSV) immunoprophylaxis (IP) use and RSV hospitalization rates (RSVH) in preterm and full-term infants without chronic lung disease of prematurity or congenital heart disease before and after the recommendation against RSV IP use in preterm infants born at 29 to 34 weeks' gestational age (wGA). STUDY DESIGN: Infants in commercial and Medicaid claims databases were followed from birth through first year to assess RSV IP and RSVH, as a function of infant's age and wGA. RSV IP was based on pharmacy or outpatient medical claims for palivizumab. RSVH was based on inpatient medical claims with a diagnosis of RSV. RESULTS: Commercial and Medicaid infants 29 to 34 wGA represented 2.9 to 3.5% of all births. RSV IP use in infants 29 to 34 wGA decreased 62 to 95% (p < 0.01) in the 2014-2015 season relative to the 2013-2014 season. Compared with the 2013-2014 season, RSVH increased by 2.7-fold (p = 0.02) and 1.4-fold (p = 0.03) for infants aged <3 months and 29 to 34 wGA in the 2014-2015 season with commercial and Medicaid insurance, respectively. In the 2014-2015 season, RSVH for infants 29 to 34 wGA were two to seven times higher than full-term infants without high-risk conditions. CONCLUSION: Following the 2014 RSV IP guidance change, RSV IP use declined and RSVH increased among infants born at 29 to 34 wGA and aged <3 months.

Healthcare costs in patients with advanced non-small cell lung cancer and disease progression during targeted therapy: a real-world observational study.

AIMS: To assess healthcare costs during treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) and following disease progression in patients with advanced non-small cell lung cancer (NSCLC). METHODS: A retrospective analysis of medical records of US community oncology practices was conducted. Eligible patients had advanced NSCLC (stage IIIB/IV) diagnosed between January 1, 2008 and January 1, 2015, initiated treatment with erlotinib or afatinib (first-line or second-line), and had disease progression. Monthly Medicare-paid costs were evaluated during the TKI therapy period and following progression. RESULTS: The study included 364 patients. The total mean monthly cost during TKI therapy was $20,106 (95% confidence interval [CI] = $16,836-$23,376), of which 47.0% and 42.4% represented hospitalization costs and anti-cancer therapy costs, respectively. Following progression on TKI therapy (data available for 316 patients), total mean monthly cost was $19,274 (95% CI = $15,329-$23,218), and was higher in the 76.3% of patients who received anti-cancer therapy following progression than in the 23.7% of those who did not ($20,490 vs $15,364; p < .001). Among patients who received it, anti-cancer therapy ($11,198; 95% CI = $7,102-$15,295) represented 54.7% of total mean monthly cost. Among patients who did not receive anti-cancer therapy, hospitalization ($13,829; 95% CI = $4,922-$22,736) represented 90.0% of total mean monthly cost. Impaired performance status and brain metastases were significant predictors of increased cost during TKI therapy. LIMITATIONS: The study design may limit the generalizability of findings. CONCLUSIONS: Healthcare costs during TKI treatment and following progression appeared to be similar and were largely attributed to hospitalization and anti-cancer therapy. Notably, almost one-quarter of patients did not receive anti-cancer therapy following progression, potentially indicating an unmet need; hospitalization was the largest cost contributor for these patients. Additional effective targeted therapies are needed that could prolong progression-free survival, leading to fewer hospitalizations for EGFR mutation-positive patients.

Trends in Utilization of Outpatient Respiratory Syncytial Virus Prophylaxis with Palivizumab among Medicaid- and Commercially Insured Infants.

INTRODUCTION: Palivizumab is indicated for the prevention of respiratory syncytial virus (RSV) infection in high-risk children. Previous palivizumab utilization studies examined prior authorization claims but did not examine utilization within insured populations as a whole. This study describes outpatient palivizumab utilization trends and characterizes high-risk infants receiving palivizumab within Medicaid- and commercially insured populations. METHODS: Infants born July 1, 2003 through June 30, 2013 were identified in the MarketScan® Multistate Medicaid and Commercial claims databases. Infants with ≥ 18 months of continuous medical insurance enrollment with pharmacy benefits after birth and evidence of chronic lung disease of prematurity (CLDP), congenital heart disease (CHD), or preterm birth without CLDP or CHD were studied. Palivizumab use and demographic and clinical characteristics were measured in infant subgroups. Outpatient palivizumab utilization rates were calculated for each seasonal year (July-June) and for each infant subgroup. RESULTS: In total, 29,350 (2.1%) Medicaid-insured and 9589 (2.5%) commercially insured infants received palivizumab and had CLDP, CHD, or were born at < 37 weeks gestational age (wGA). Infants with CLDP (82%) and those < 29 wGA (78%) had the highest utilization. Decreases in utilization rates between the 2003-2004 and 2012-2013 seasons were seen among Medicaid-insured infants born at 29-36 wGA (all P < .0001), and commercially insured infants born at 31-32 wGA (P < .0001), 33-34 wGA (P = .055), 35-36 wGA (P < .0001), and with CHD (P = .003). Utilization by month was consistent across subgroups among Medicaid- and commercially insured infants, with most doses administered from November to March. CONCLUSION: Palivizumab use is targeted to a small percentage of infants who are at highest risk of hospitalization for RSV disease. Utilization declined in recent years in both Medicaid- and commercially insured infant groups. Most palivizumab doses were administered from November to March, with most infants receiving ≤ 5 doses. FUNDING: AstraZeneca.

Chronologic Age at Hospitalization for Respiratory Syncytial Virus Among Preterm and Term Infants in the United States.

INTRODUCTION: Respiratory syncytial virus (RSV) is the leading cause of hospitalization among infants in the United States, and the risk for RSV hospitalizations is greater for infants born preterm. Recent studies in preterm and term infants have shown that RSV hospitalization rates vary considerably depending on infant chronologic age. This study sought to aggregate the data available from published literature and from nationally representative databases of US infant hospitalizations to generate a composite description of the effect of young chronologic age on RSV hospitalizations among US preterm and term infants by individual month of age. METHODS: Data describing the relative incidence of RSV hospitalizations by individual month of chronologic age during the first year of life were obtained from recently published studies, the 2006-2011 National Inpatient Sample databases, and the 2006 and 2009 Kids Inpatient Databases. RESULTS: All data sources showed that ≥20% of infant RSV hospitalizations occurred in the second month of life and >50% and >75% of RSV hospitalizations were observed during the first 3 and 6 months of life, respectively. These findings were consistent for both preterm and term infants. CONCLUSION: Data from multiple sources demonstrate that the greatest risk of RSV hospitalization occurs during the first 6 months of life among US preterm and term infants. Strategies to prevent infant RSV hospitalizations should be targeted to infants during the first months of life. FUNDING: AstraZeneca.