Bacterial Vaginosis Treatment Patterns, Associated Complications, and Health Care Economic Burden of Women With Medicaid Coverage in the United States.

BACKGROUND: Bacterial vaginosis (BV) is a highly prevalent vaginal infection. OBJECTIVES: Primary objectives of this study were to examine treatment patterns among female patients with Medicaid coverage who were diagnosed with incident BV, the frequency of BV-associated complications, and health care resource utilization (HCRU) and associated costs of incident BV and its recurrence. Secondary objectives were to identify predictors of total all-cause health care costs and number of treatment courses. METHODS: Female patients aged 12-49 years with an incident vaginitis diagnosis and ≥1 pharmacy claim for a BV medication were selected from the Merative MarketScan Medicaid database (2017-2020). Additional treatment courses were evaluated during a ≥12-month follow-up period, in which new cases of BV-associated complications and HCRU and the associated costs were also measured. Generalized linear models were used to identify baseline predictors of total all-cause health care costs and number of treatment courses. RESULTS: An incident vaginitis diagnosis and ≥1 BV medication claim were present in 114 313 patients (mean age: 28.4 years; 48.6% black). During the follow-up, 56.6% had 1 treatment course, 24.9% had 2, 10.2% had 3, and 8.3% had ≥4; 43.4% had BV recurrence. Oral metronidazole (88.5%) was the most frequently prescribed medication. Nearly 1 in 5 had a new occurrence of a BV-associated complication; most (76.6%) were sexually transmitted infections (STIs). Total all-cause and BV-related costs averaged $5794 and $300, respectively, per patient; both increased among those with more treatment courses. Older age, pregnancy, comorbidity, any STIs, postprocedural gynecological infection (PGI), and infertility were predictive of higher total all-cause health care costs, while race/ethnicity other than white was predictive of lower costs. Older age, black race, any STIs, pelvic inflammatory disease, and PGI were predictive of >1 treatment courses. CONCLUSION AND RELEVANCE: The high recurrence of BV represents an unmet need in women's health care and better treatments are necessary.

Treatment patterns and economic burden of bacterial vaginosis among commercially insured women in the USA.

Aim: Bacterial vaginosis (BV) is a common vaginal dysbiosis associated with adverse clinical sequelae, most notably, increased risk of sexually transmitted infections (STIs). The aims of this study were to estimate the frequency of BV recurrence, treatment patterns, other gynecological (GYN) conditions, and the associated healthcare resource utilization (HCRU) and costs among commercially insured patients in the USA. Patients & methods: Female patients aged 12-49 years with an incident vaginitis diagnosis and ≥1 pharmacy claim for a BV medication (fungal treatment only excluded) were selected from the Merative™ MarketScan commercial database (2017-2020). During a minimum 12-month follow-up, additional treatment courses, treatment patterns, frequency of other GYN conditions, and HCRU and costs were assessed. Generalized linear models were used to identify baseline predictors of total all-cause healthcare costs and number of treatment courses. Results: The study population included 140,826 patients (mean age: 31.5 years) with an incident vaginitis diagnosis and ≥1 BV medication claim. During the follow-up, 64.2% had 1 treatment course, 22.0% had 2, 8.1% had 3, and 5.8% had ≥4; 35.8% had a BV recurrence (≥2 BV medication claims). The most commonly prescribed BV medication was oral metronidazole (73.6%). Approximately 12% (n = 16,619) of patients had a new diagnosis of another GYN condition in the follow-up; 8.2% had a new STI, which were more common among patients with ≥4 treatment courses (12.9%). During follow-up, total all-cause healthcare costs averaged $8987 per patient per year (PPPY) of which $470 was BV-related. BV-related healthcare costs increased from $403 PPPY among those with 1 treatment course to $806 PPPY among those with ≥4 with nearly half the costs attributed to outpatient office visits. Conclusion: BV recurrence among this population represented a substantial clinical and healthcare economic burden warranting improvements in women's healthcare.

A real-world study of acute and preventive medication use, adherence, and persistence in patients prescribed fremanezumab in the United States.

BACKGROUND: Following approval of fremanezumab for the prevention of migraine in adults, health care decision makers are interested in understanding real-world clinical characteristics and treatment patterns among patients initiating fremanezumab therapy. METHODS: Data were obtained for this retrospective (pre-post) study from the Veradigm Health Insights database. The study period was January 1, 2014, to June 30, 2019. Patients were included if they were aged ≥ 18 years; had ≥ 1 migraine diagnosis during the study period; and had a medication record for fremanezumab on or after diagnosis during the identification period (September 1, 2018-December 31, 2018). Treatment patterns, including adherence, persistence, and utilization of acute and preventive migraine medication prescriptions, were evaluated. RESULTS: Of 987 patients initiating fremanezumab during the study period, 738 (74.8%) were adherent to fremanezumab by proportion of days covered (PDC; ≥ 80%) and 780 (79.0%) were adherent by medication possession ratio (MPR; ≥ 80%). A total of 746 (75.6%) patients were persistent for ≥ 6 months. Quarterly fremanezumab (n = 186) was associated with higher rates of adherence versus monthly fremanezumab (n = 801) by PDC (quarterly, 91.3%; monthly, 84.9%; P < 0.001) and MPR (quarterly, 92.2%; monthly, 87.9%; P = 0.006) and higher persistence at ≥ 6 months (quarterly, 82.8%; monthly, 73.9%; P = 0.011). After fremanezumab initiation, patients who were persistent for ≥ 6 months experienced significant reductions from baseline in the mean monthly number of acute and preventive migraine medication prescriptions (P < 0.001). Subgroup analyses in patients with comorbid depression and anxiety showed meaningful real-world benefits based on significant reductions in the number of patients who were prescribed antidepressants (baseline, 68.6%; follow-up, 56.4%; P = 0.0025) and anxiolytic medications (baseline, 55.0%; follow-up, 47.2%; P = 0.037), respectively. In a subgroup of patients with comorbid hypertension at baseline, fremanezumab treatment resulted in nonsignificant reductions in blood pressure. CONCLUSIONS: Overall, adherence and persistence to fremanezumab in this real-world study was high in patients with migraine, with higher rates observed for quarterly fremanezumab. Patients who were persistent for ≥ 6 months experienced significant reductions in acute and preventive migraine medication use, while a subgroup of migraine patients with comorbid depression and anxiety at baseline showed significant reductions in antidepressant and anxiolytic medication use.

Real-world impact of fremanezumab on migraine symptoms and resource utilization in the United States.

BACKGROUND: Fremanezumab, a fully humanized monoclonal antibody (IgG2Δa) that selectively targets calcitonin gene-related peptide (CGRP), is approved for migraine prevention in adults. Real-world data on the effectiveness of fremanezumab are limited. This retrospective, observational cohort study assessed patient-reported migraine symptoms, health care resource utilization (HCRU), and direct medical costs before and after fremanezumab treatment initiation. METHODS: Data were extracted from September 2018 through June 2020 from the Midwest component of EMRClaims+®, an integrated health services database containing > 20 million medical records from national commercial insurance claims, Medicare claims, and regional electronic medical records. Patients included in the cohort analysis were aged ≥ 18 years and were administered fremanezumab, with enrollment or treatment history for ≥ 6 months prior (pre-index) to initiating fremanezumab (index date) and ≥ 1 month after the index date (post-index), and without pregnancy or pregnancy-related encounters during the study period. Patient-reported headache frequency, migraine pain intensity (MPI), composite migraine symptoms, and HCRU were assessed pre-index and ≥ 1 month after fremanezumab initiation. Wilcoxon signed-rank tests were used to compare means of migraine symptoms and outcomes and HCRU before and after fremanezumab initiation. RESULTS: Overall, 172 patients were eligible for analysis. Of patients who self-reported (n = 129), 83.7% reported improvement in headache frequency or symptoms after fremanezumab treatment. Specifically, headache frequency decreased by 63% after fremanezumab initiation: mean (standard deviation) headache frequency was 22.24 (9.29) days per month pre-index versus 8.24 (7.42) days per month post-index (P < 0.0001). Mean MPI also decreased by 18% after fremanezumab initiation: MPI was 5.47 (3.19) pre-index versus 4.51 (3.34) post-index (P = 0.014). Mean emergency room (ER) visits per month decreased from 0.72 to 0.54 (P = 0.003), and mean outpatient visits per month decreased from 1.04 to 0.81 (P < 0.001). Mean hospitalizations per month decreased, but the results did not reach statistical significance (P = 0.095). Hospitalization and ER costs decreased, while outpatient costs increased, from pre-index to post-index, but differences were not statistically significant (P ≥ 0.232). CONCLUSIONS: Significant reductions in headache frequency, MPI, and HCRU were observed after fremanezumab initiation in patients with migraine in a US real-world setting.

Concurrent or layered treatment with radium-223 and enzalutamide or abiraterone/prednisone: real-world clinical outcomes in patients with metastatic castration-resistant prostate cancer.

BACKGROUND: In this study, we evaluated real-world data on radium-223 plus abiraterone/prednisone or enzalutamide. Previously, the ERA 223 trial (NCT02043678) demonstrated increased fracture risk with concurrent treatment with radium-223 and abiraterone plus prednisone/prednisolone in patients with metastatic castration-resistant prostate cancer (mCRPC). METHODS: We used the Flatiron Health database to perform a retrospective study of patients with mCRPC treated with radium-223. Treatment with radium-223 plus abiraterone/prednisone or enzalutamide was defined as concurrent if both drugs started within 30 days of one another, or layered when the second drug started ≥30 days after the first. The index date was defined as the day of the first radium-223 dose. Outcome measures included symptomatic skeletal events (SSEs), overall survival (OS), and patterns of treatments received. RESULTS: Of the 625 patients treated with radium-223, 22% received it together with abiraterone/prednisone and 27% with enzalutamide. When these agents were combined, they were often initiated in a layered fashion (73% layered, 23% concurrent). Prior or concomitant bone health agents (BHAs) were received by 67% and 55% of patients, respectively. Median follow-up was 9 months. Overall, incidence rates for SSEs and pathologic fractures were 0.35 and 0.11 patients per person-year, respectively. Median OS from mCRPC diagnosis was 28.1 months. CONCLUSIONS: In this real-world setting, combination treatments with radium-223 and abiraterone/prednisone or enzalutamide were common. These agents were more commonly given in a layered than a concurrent fashion. Incidence rates for SSEs were reduced when BHAs were used; however, BHAs were underutilized.

Treatment Patterns and Outcomes in Patients With Metastatic Castration-resistant Prostate Cancer in a Real-world Clinical Practice Setting in the United States.

BACKGROUND: Clinical trials have demonstrated the efficacy of several life-prolonging therapies for metastatic castration-resistant prostate cancer (mCRPC); however, real-world data on their use, survival effect, and safety are limited. Using electronic health record data from the Flatiron Health database, we studied real-world treatment patterns and health outcomes in patients with mCRPC. PATIENTS AND METHODS: We conducted a retrospective, non-interventional cohort analysis of electronic health record data of patients with confirmed mCRPC between January 2013 and September 2017. The primary objective was to describe real-world treatment patterns, including treatment type, duration, and sequencing. Secondary objectives included describing patient characteristics and clinical outcomes. RESULTS: Of 2559 patients with mCRPC, 1980 (77%) received at least 1 line of life-prolonging therapy (abiraterone, enzalutamide, docetaxel, cabazitaxel, sipuleucel-T, or radium-223). Of patients receiving first-line therapy, 49% received second-line therapy, and of these, 43% received third-line therapy. Abiraterone/prednisone and enzalutamide accounted for 65% of first-line therapies and 54% of second-line therapies. Docetaxel was the most common third-line therapy (24%). Back-to-back use of abiraterone/prednisone and enzalutamide was common. Radium-223 monotherapy use was 2% in the first-line setting, 3% in the second-line setting, and 8% in the third-line setting. The median overall survival was longer in patients who received life-prolonging therapies (23.7 months; 95% confidence interval: 22.3-25.1 months) than in those who did not (10.1 months; 95% confidence interval: 9.1-11.5 months). CONCLUSION: These real-world insights on over 2500 patients with mCRPC supplement findings from randomized controlled trials and may help to inform clinical trial design, treatment guidelines, and clinical decision-making.

A Retrospective Claims Analysis of Advanced Prostate Cancer Costs and Resource Use.

BACKGROUND: Castration-resistant prostate cancer (CRPC) is associated with high costs and healthcare resource utilization (HCRU). OBJECTIVE: This study followed patients with CRPC through their continuum of care and analyzed claims data regarding treatments, total HCRU, and costs, both before and after metastasis diagnosis. METHODS: A retrospective cohort of patients with newly diagnosed metastatic CRPC (mCRPC) in the USA was identified from the Truven Health MarketScan database from January 2009 to March 2015. The mCRPC algorithm employed International Classification of Diseases, Ninth Revision codes for prostate cancer (pre-index) and secondary metastatic disease (index date) and a subsequent claim for a US FDA-approved treatment for mCRPC. Patient inclusion required evidence of surgical or pharmacological castration and no evidence of bone-targeted treatments during the baseline period while evaluating continuous enrollment 25 months pre-index and 6 months post-index. Treatment patterns were assessed during pre- and post-index periods; HCRU and costs were annualized for comparison purposes regarding both pre- and post-index timeframes. RESULTS: Among 261 patients with mCRPC (mean age 72 years), the most common treatments during the pre-index period were bicalutamide (90.04%), leuprolide (81.99%), abiraterone (22.22%), docetaxel (20.69%), and ketoconazole (18.01%). Mean per-patient-per-year (PPPY) all-cause annualized healthcare costs significantly increased from $US35,102.55 in the pre-index nonmetastatic CRPC (nmCRPC) period to $US156,499.89 after metastasis diagnosis (mCRPC). Mean PPPY inpatient admissions and emergency department visits increased from 0.20 to 1.36 and from 0.63 to 1.56, respectively. CONCLUSIONS: Average yearly costs and HCRU were four times higher following mCRPC diagnosis, indicating a need for appropriate management strategies to optimize the potential delay of disease progression among patients with nmCRPC.

Costs and Healthcare Resource Utilization Associated with Hospital Admissions of Patients with Metastatic or Nonmetastatic Prostate Cancer.

BACKGROUND: Limited published information exists that compares the costs of metastatic prostate cancer with nonmetastatic prostate cancer. Although most research has focused on the costs of metastatic prostate cancer, delaying metastases in patients with nonmetastatic prostate cancer can reduce or delay healthcare resource utilization and any associated expenditures. OBJECTIVE: To compare the costs and healthcare resource utilization of patients with metastatic or nonmetastatic prostate cancer who were receiving care in an inpatient or an outpatient hospital setting. METHODS: Claims from between June 2010 and September 2016 of patients with metastatic or nonmetastatic prostate cancer were retrospectively identified from the Premier Healthcare Database. Patients with a primary diagnosis of malignant neoplasm of the prostate in the inpatient or outpatient setting during the study period were included. Admissions were categorized as metastatic or nonmetastatic prostate cancer based on the presence or absence of an International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) and/or ICD-10-CM code for metastatic prostate cancer on discharge. Patients with a secondary diagnosis of distant skeletal, lymph node, or visceral metastasis or who received ≥1 treatments indicative of bone metastasis on the same admission were considered to have metastatic prostate cancer. RESULTS: The study included prostate cancer admissions totaling 78,667 inpatient (4576 with metastatic disease) and 874,366 outpatient (71,545 with metastatic disease) admissions. Among the metastatic prostate cancer inpatient admissions, 72.6% of the patients were aged ≥65 years (mean age, 72 years for metastatic disease vs 63 years for nonmetastatic disease) and approximately 77.5% of these patients had bone metastases. The mean total cost per inpatient admission was $12,324 (standard deviation [SD], $13,506) for metastatic prostate cancer versus $10,987 (SD, $6912) for nonmetastatic disease. The mean total cost per outpatient admission was $1627 (SD, $6182) for metastatic versus $909 (SD, $3458) for nonmetastatic prostate cancer. CONCLUSIONS: The results of this study demonstrate the increased economic burden associated with hospital admissions, particularly inpatient admissions, for patients with metastases compared with patients without metastases. In addition to the clinical burden on patients, these findings further highlight the importance of implementing treatment strategies that can delay progression to metastatic prostate cancer and subsequent increases in healthcare resource utilization and cost.

A Clinical and Economic Comparison of Rasburicase and Allopurinol in the Treatment of Patients With Clinical or Laboratory Tumor Lysis Syndrome.

BACKGROUND: The aim of the study was to compare reductions in uric acid (UA), length of stay (LOS), and hospitalization costs in patients with tumor lysis syndrome (TLS) treated with rasburicase or allopurinol. PATIENTS AND METHODS: This retrospective study of administrative data included hospitalized pediatric and adult patients who had clinical or laboratory TLS and received rasburicase or allopurinol. Each rasburicase-treated patient was propensity score-matched with 4 allopurinol-treated patients. Mean changes in UA within ≤ 2 days of treatment initiation were determined. Economic outcomes included mean number of days in the intensive care unit (ICU), total LOS, costs/hospitalization, and costs/percentage change in UA. RESULTS: Twenty-six rasburicase-treated patients were matched with 104 allopurinol-treated patients. Reduction in plasma UA was 5.3 mg/dL greater for patients treated with rasburicase than for patients treated with allopurinol (P < .0001). Length of ICU stay was 2.5 days less for patients treated with rasburicase than for patients treated with allopurinol (P < .0001), and total LOS was 5 days less for patients treated with rasburicase than for patients treated with allopurinol (P = .02). Total costs per patient were $20,038 lower for patients treated with rasburicase than for patients treated with allopurinol (P < .02). Cost per percentage UA reduction was also lower for patients treated with rasburicase versus patients treated with allopurinol ($3899 vs. $16,894; P < .001). CONCLUSION: In this analysis of TLS patients who received care in real-world settings, rasburicase versus allopurinol was significantly more effective in treating hyperuricemia and was associated with significantly shorter ICU and overall hospital stays and lower total inpatient costs.

Opioid Use Among Metastatic Prostate Cancer Patients With Skeletal-related Events.

PURPOSE: The development of skeletal-related events (SREs) (pathologic fracture, need for surgery and/or radiation to bone, spinal cord compression, and hypercalcemia of malignancy) in metastatic prostate cancer (MPC) is associated with worsened pain and compromised quality of life. Opioids are frequently used throughout the course of SRE treatment. This study describes the treatment patterns and incremental use of opioids in MPC patients diagnosed with SREs. METHODS: PC patients with bone metastases newly diagnosed with an SRE between January 1, 2005, and September 30, 2014, were identified using MarketScan Commercial and Medicare databases. Included patients were aged ≥40 years, had medical/pharmacy benefits for ≥12 months before (preindex) and ≥6 months after (postindex) diagnosis, and were without evidence of other primary cancers. Patients were categorized as nonusers of opioids (<10 days), short-term users (≥10 and <60 days), or long-term users (≥60 days) and further by SRE type. Opioid type, proportion of time on opioids, morphine-equivalent dose, adjuvant medications, and radiation use before and after SRE diagnosis were evaluated. FINDINGS: A total of 1071 eligible patients were identified (mean age, 71 years; 10.8% had chronic pain at baseline). The most common SRE types present were radiation (60.2%), radiation and bone surgery (15.0%), pathologic fracture (7.2%), and bone surgery (6.5%). Opioid use increased from 49.9% preindex to 53.3% postindex (P < 0.0001). The proportion of time on opioids doubled after SRE (pre, 0.3 vs post, 0.6; P < 0.0001). A greater percentage of patients used only opioids after an SRE (pre, 11.0%; post, 46.1% [P < 0.0001]), while a lesser percentage of patients used only radiation after an SRE (pre, 36.0%; post, 4.7% [P < 0.0001]). An increase was observed in patients using neither radiation nor opioids (pre, 14.5%; post, 42.0% [P < 0.0001]). An increase of ~50% was noted in long-term opioid users (from 22.1% to 32.1%). The use of monotherapy with a short-acting opioid decreased (pre, 35.1%; post, 32.5% [P < 0.0001]), while use of mixed opioids increased (pre, 13.7%; post, 19.1% [P < 0.0001]). Mean morphine-equivalent dose increased from pre- to post-SRE (9.1 vs 13.1 mg). Bisphosphonate and NSAID users decreased from before to after an SRE diagnosis (bisphosphonates, 40.2% vs 8.6%; NSAIDs, 26.7% vs 17.5% [both, P < 0.0001]). IMPLICATIONS: Long-term opioid use and dose were significantly increased after SRE development in MPC. The high percentage of patients not treated with an opioid or radiation potentially supports the need for additional treatment options for controlling pain if medically necessary and/or to prevent SREs.

Adherence to risk evaluation and mitigation strategies (REMS) requirements for monthly testing of liver function.

BACKGROUND: Risk evaluation and mitigation strategies (REMS), as mandated by the US Food and Drug Administration (FDA) for medications with the potential for harm, are increasingly incorporating rigid protocols for patient evaluation, but little is known about compliance with these programs. Despite the inherent limitations, data on administrative claims may provide an opportunity to investigate adherence to these programs. METHODS: We assessed adherence to liver function test (LFT) requirements included in the REMS program for bosentan through use of administrative claims. Patients observed in the Optum Research Database who were initiators of bosentan from November 20, 2001 to March 31, 2013 were included. Adherence to LFTs was calculated using pharmacy claims for bosentan dispensation and medical claims for laboratory services, and was assessed at the time of drug initiation and within specified time intervals throughout follow-up. RESULTS: Of 742 patients, 523 (70.5%) had ≥1 qualifying LFT. Among patients with ≥12 dispensations, claims for LFTs at individual dispensations were 53.2-64.0%. Median proportion of dispensations with ≥1 LFT was 0.8 among patients with ≥6 (interquartile range, 0.7-1.0) or ≥12 (0.7-0.9) dispensations. Adherence was 90-100% for 33.3% of all initiators, whereas 29.3% of initiators were non-adherent (defined as <50% of on-therapy LFTs). CONCLUSIONS: Analyses of administrative claims suggest that the REMS program for bosentan may not have adequately guaranteed adherence to the program's monthly monitoring of LFTs. Such investigations of existing REMS programs may provide insight on how to accomplish more successful evaluation of REMS.

Real-world outcomes of initiating insulin glargine-based treatment versus premixed analog insulins among US patients with type 2 diabetes failing oral antidiabetic drugs.

BACKGROUND: In patients with type 2 diabetes mellitus, basal-bolus strategies can improve treatment by offering dosing flexibility, and improved satisfaction, adherence, and clinical outcomes. The purpose of this study was to compare real-world outcomes between US patients initiating analog insulin therapy with insulin glargine and those initiating with a premixed analog insulin (PMX). METHODS: This was a retrospective study of data from patients (≥18 years) with type 2 diabetes mellitus in the IMPACT® database who initiated insulin treatment with insulin glargine (GLA) or a PMX. Clinical and economic outcomes were measured over one year, including persistence and adherence, consumption of insulin, glycemic outcomes, incident hypoglycemia, and health care resource utilization and cost. RESULTS: Data from 2,502 patients were included in the analyses (n = 834 for PMX, n = 1,668 for GLA). Compared with PMX, persistence was higher and consumption of insulin was lower for GLA (both P < 0.0001). Adherence, glycemic outcomes, and hypoglycemia-related events were similar between groups, as were health care utilization and total health care costs. Diabetes-related drug and supply costs were lower for GLA than for PMX (P < 0.0001 and P = 0.046, respectively). CONCLUSION: In US patients with type 2 diabetes mellitus, initiating insulin with once-daily GLA, rather than a PMX, is associated with increased treatment persistence and similar clinical and hypoglycemic outcomes, but lower diabetes pharmacy and supply costs. GLA may be a more flexible option than PMX. However, these results also show suboptimal glycemic control in the real-world setting despite change in treatment regimens and call for optimization in management of patients with type 2 diabetes mellitus.

Economic implications of rasburicase treatment in adult patients with tumour lysis syndrome.

BACKGROUND: Rasburicase is a recombinant urate-oxidase enzyme used to reduce high levels of plasma uric acid (PUA) resulting from tumour lysis syndrome (TLS). Rasburicase reduces PUA levels within 4 hours of administration, thereby minimizing the risk of serious complications from TLS. Treatment pattern analyses indicate rasburicase is often used in combination with allopurinol; however, no studies have evaluated the clinical and economic consequences of this pattern of care. The purpose of this study was to compare hospitalization costs, overall length of stay (LOS), and critical-care LOS in patients receiving rasburicase with or without allopurinol. METHODS: Hospital claims data from the Premier Perspective Database™ were used to conduct this retrospective analysis. Patients in the Premier hospital database who were administered rasburicase or combination therapy (rasburicase + allopurinol) within 2 days of hospital admission were eligible for study inclusion. Patients were excluded if they were <18 years of age or received haemodialysis (or any other renal replacement therapy support) on admission. Rasburicase patients were propensity-score-matched to combination therapy patients based on gender, race, hospital type (urban/rural, teaching), provider type, payer type, admission source, use of electrolyte modification therapy, critical-care admission and presence of a cancer diagnosis. Differences in healthcare costs, overall LOS and critical-care LOS were assessed using γ-distributed generalized linear models with a log-link function. RESULTS: The study population comprised 66 patients receiving rasburicase monotherapy matched to 66 patients receiving combination therapy. Mean age was 62.9 years, and 29% were female. Patients initiated on combination therapy had a shorter mean duration of rasburicase administration than patients initiated on monotherapy (2.1 vs 2.7 days) [p = 0.0059]. Additionally, rasburicase monotherapy incurred an average total cost of $US35 843 per hospitalization, compared with $US46 672 for those receiving combination therapy (p = 0.0820). Rasburicase monotherapy patients also had a shorter mean overall LOS (10.0 days vs 15.4 days; p = 0.0067). The mean critical-care LOS was similar in both cohorts (2.4 days rasburicase vs 2.9 days combination therapy; p = 0.3389). CONCLUSION: Examination of claims data showed that combination therapy (rasburicase + allopurinol) trended toward higher total hospitalization costs than rasburicase monotherapy. In addition, combination therapy was associated with significantly longer overall LOS compared with upfront rasburicase monotherapy in patients at risk for developing TLS.