Clinical outcomes of adjuvant nivolumab in resected stage III melanoma: comparison of CheckMate 238 trial and real-world data.

OBJECTIVES: Nivolumab is approved as adjuvant therapy for resected stage III/IV melanoma based on the phase 3 CheckMate 238 trial. This analysis compared outcomes from CheckMate 238 with those from the real-world Flatiron Health electronic health record-derived de-identified database in patients with resected stage III melanoma (per AJCC-8) treated with adjuvant nivolumab. MATERIALS: Outcomes included baseline characteristics, overall survival (OS) in the CheckMate 238 cohort (randomization until death or last known alive), and real-world overall survival (rwOS) in the Flatiron Health cohort (nivolumab initiation until death or data cutoff). rwOS was compared with OS using unadjusted and adjusted Cox proportional hazards models. Inverse probability of treatment weighting (IPTW) was combined with the adjusted model to reduce baseline discrepancies. RESULTS: The CheckMate 238 and real-world cohorts included 369 and 452 patients, respectively (median age, 56.0 and 63.0 years; median follow-up, 61.4 vs. 25.5 months). rwOS was not different from OS in the unadjusted (hazard ratio [HR] 1.27; 95% CI 0.92-1.74), adjusted (HR 1.01; 95% CI 0.67-1.54), and adjusted IPTW (HR 1.07; 95% CI 0.70-1.63) analyses. In the adjusted analysis, 2-year OS and rwOS rates were 84%. Median OS and rwOS were not reached. After IPTW, OS and rwOS were not different (HR 1.07; 95% CI 0.70-1.64). CONCLUSIONS: In this comparative analysis, OS in the CheckMate 238 trial was similar to rwOS in the Flatiron Health database after adjustments in patients with resected stage III melanoma (per AJCC-8) treated with adjuvant nivolumab, validating the trial results.

Cytochrome P450 inhibitor/inducer treatment patterns among patients in the United States with advanced ovarian cancer who were prescribed or were eligible for poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitors in the first-line maintenance setting.

Poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitors (PARPi) are metabolized either via carboxylesterase (niraparib) or cytochrome P450 (CYP) enzymes (olaparib and rucaparib). Patients with advanced epithelial ovarian cancer (aOC) who receive concomitant medication metabolized by the CYP system may be at risk of drug-drug interactions impacting PARPi efficacy and tolerability. This study investigated CYP inhibitor/inducer treatment patterns in the first-line maintenance (1Lm) setting for patients with aOC. This retrospective cohort study used de-identified databases of US patients with aOC. Eligible patients were aged ≥18 years, diagnosed with aOC between January 2015-March 2021, and received CYP inhibitors/inducers during 1Lm PARPi initiation or the eligibility window (90 days before to 120 days after first-line platinum-based therapy ended [index]). Patients were either prescribed 1Lm PARPi monotherapy (PARPi cohort) or were not prescribed any 1Lm therapy within 120 days post-index (PARPi-eligible cohort). Strong/moderate CYP inhibitors/inducers were defined as area under the plasma concentration-time curve ratio (AUCR) ≥2 or clearance ratio (CL) ≤0.5 (inhibitors), and AUCR ≤0.5 or CL ratio ≥2 (inducers). Of 1411 patients (median age 63), 158 were prescribed PARPis and 1253 were PARPi-eligible. Among the PARPi cohort, 46.2%, 48.7%, and 5.1% were prescribed niraparib, olaparib, and rucaparib, respectively. For patients prescribed olaparib or rucaparib, 42.4% also received strong and/or moderate CYP inhibitors/inducers. This real-world study indicated a considerable proportion of patients received strong and/or moderate CYP inhibitors/inducers and were prescribed PARPis metabolized by the CYP system. Understanding potential impacts of concomitant CYP inhibitors/inducers on PARPi efficacy and safety is warranted.

Characteristics and treatment patterns of relapsed/refractory diffuse large B-cell lymphoma in patients receiving ≥3 therapy lines in post-CAR-T era.

OBJECTIVE: Several novel treatments have been approved for relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL) since chimeric antigen receptor T-cell (CAR-T) therapy became available. The objective of this study was to describe characteristics and treatment patterns in patients with R/R DLBCL post-CAR-T approval. METHODS: Adult patients with R/R DLBCL who initiated third-line treatment or later (3 L+) since 18 October 2017 were identified using administrative claims from IQVIA PharMetrics Plus (1 January 2014-31 March 2020). Treatments were categorized as chemotherapy/chemoimmunotherapy (CT/CIT), targeted therapies, CAR-T and stem cell transplant (SCT). Treatment distribution, treatment duration of CT/CIT and targeted therapies, and initiation of next-line therapy were described for patients receiving 3 L; analyses were repeated for 4 L. RESULTS: A total of 145 patients received 3 L between 18 October 2017 and 31 March 2020. Mean age was 57 years, and 34% were female. CT/CIT (44.9%), targeted therapies (26.9%), CAR-T (17.2%) and SCT (11.0%) were administered in 3 L. The median treatment duration was 2.9 months for CT/CIT and targeted therapies combined. 31% of patients initiated 4 L within a median follow-up of 5.8 months. Among patients who received 4 L (N = 55), targeted therapies were most commonly used (36.4%), and the median treatment duration was 2.5 months. CONCLUSIONS: Post-CAR-T approval, the majority of patients were treated with CT/CIT or targeted therapies in 3 L and 4 L, though most of the targeted therapies prescribed are not indicated for DLBCL. Treatment duration was short. A high proportion of patients moved to the next line of therapy (LOT) during a short follow-up period. This study highlights the unmet need for more effective treatments for patients with R/R DLBCL in 3 L+.

Treatment Patterns, Complications, and Health Care Utilization Among Endometriosis Patients Undergoing a Laparoscopy or a Hysterectomy: A Retrospective Claims Analysis.

INTRODUCTION: Hysterectomy and laparoscopy are common surgical procedures used for the treatment of endometriosis. This study compares outcomes for women who received either procedure within the first year post initial surgery. METHODS: The study used data from the Truven Health MarketScan claims databases from 2004 to 2013 to identify women aged 18-49 years who received an endometriosis-related laparoscopy or hysterectomy. Patients were excluded if they did not have continuous insurance coverage from 1 year before through 1 year after their endometriosis-related procedure, if they were diagnosed with uterine fibroids prior to or on the date of surgery (i.e., index date), or if they had a hysterectomy prior to the index date. The descriptive analyses examined differences between patients with an endometriosis-related laparoscopy or hysterectomy in regard to medications prescribed, complications, and hospitalizations during the immediate year post procedure. RESULTS: The final sample consisted of 24,915 women who underwent a hysterectomy and 37,308 who underwent a laparoscopy. Results revealed significant differences between the cohorts, with women who received a laparoscopy more likely to be prescribed a GnRH agonist, progestin, danazol, or an opioid analgesic in the immediate year post procedure compared to women who underwent a hysterectomy. In contrast, women who underwent a hysterectomy generally had higher complication rates. Index hospitalization rates and length of stay (LOS) were higher for women who had a hysterectomy, while post-index hospitalization rates and LOS were higher for women who had a laparoscopy. For both cohorts, post-procedure complications were associated with significantly higher hospitalization rates and longer LOS. CONCLUSION: This study indicated significantly different 1-year post-surgical outcomes for patients who underwent an endometriosis-related hysterectomy relative to a laparoscopy. Furthermore, the endometriosis patients in this analysis had a considerable risk of surgical complications, subsequent surgeries, and hospital admissions, both during and after their initial therapeutic laparoscopy or hysterectomy. FUNDING: AbbVie.

Systematic Literature Review and Meta-analysis of Tumor Necrosis Factor-Alpha Experienced Rheumatoid Arthritis.

PURPOSE: The goal of this study was to compile all available evidence regarding the efficacy of tumor necrosis factor-α (TNF) inhibitors, non-TNF biologics, and tofacitinib for TNF-experienced patients who have rheumatoid arthritis (RA). METHODS: A systematic literature review of MEDLINE, EMBASE, and rheumatology conference abstracts was performed to identify observational studies and randomized controlled trials (RCTs) reporting American College of Rheumatology response rates (ACR 20/50/70) for adult patients with RA who switched from at least 1 TNF to another TNF or a non-TNF therapy. A direct random effects meta-analysis was performed to evaluate ACR 20/50/70 response rates for TNF and non-TNF therapies. Separate analyses were conducted among 3-, 6-, and 12-month observational studies and for 6-month RCTs. FINDINGS: A total of 18 observational studies and 6 RCTs were selected. Among 3-month observational studies, the percentages of ACR20/50/70 responders switching to another TNF were similar to those switching to a non-TNF biologic (ACR20, 54.5% vs 58.6%; ACR50, 33.3% vs 33.3%; and ACR70, 13.0% vs 14.6%, respectively). Among 6-month observational studies, the percentages of TNF ACR20/50/70 responders were higher than those of non-TNF responders (ACR20, 67.7% vs 50.4%; ACR50, 50.4% vs 26.6%; and ACR70, 24.9% vs 11.6%). Among 6-month RCTs, the percentages of non-TNF biologic ACR20/50/70 responders were similar to those in the 6-month non-TNF observational studies (ACR20, 50.7% vs 50.4%; ACR50, 27.5% vs 26.6%; and ACR70, 11.9% vs 11.6%). For 12-month observational studies, TNF biologic ACR20/50/70 percentages were higher than those of non-TNF therapies (ACR20, 72.2% vs 57.0%; ACR50, 42.1% vs 28.9%; and ACR70, 22.9% vs 10.0%). IMPLICATIONS: For TNF-experienced patients with RA, subsequent TNF therapy and non-TNF biologic therapy have comparable efficacy.

Real-World Outcomes of Acute Ischemic Stroke Treatment with Intravenous Recombinant Tissue Plasminogen Activator.

BACKGROUND AND PURPOSE: In clinical trials, intravenous (IV) recombinant tissue-type plasminogen activator (rt-PA) reduces the likelihood of disability if given within 3 hours of acute ischemic stroke. This study compared real-world outcomes between patients treated and patients not treated with IV rt-PA. METHODS: In this retrospective study, United States-based neurologists randomly selected eligible acute ischemic stroke patients from their charts who were and were not treated with IV rt-PA. Mortality, hospital readmission, and independence were compared between patients treated and patients not treated with IV rt-PA using Kaplan-Meier curves, log-rank tests, and Cox proportional hazards models. RESULTS: A total of 1026 charts were reviewed with a median follow-up time of 15.5 months. Pretreatment stroke severity, as measured by the National Institutes of Health Stroke Scale, was comparable between cohorts (IV rt-PA =11.7; non-rt-PA = 11.3; P = .165). IV rt-PA patients experienced significantly longer survival (P = .013), delayed hospital readmission (P = .012), and shorter time to independence (P < .001) compared with patients not treated with rt-PA. After adjusting for baseline characteristics, IV rt-PA patients had significantly lower mortality (hazard ratio [95% confidence interval] = .52 [.30, .90]) and greater rates of independence (hazard ratio [95% confidence interval] = 1.42 [1.17, 1.71]) than patients not treated with rt-PA. CONCLUSIONS: This real-world study indicated that acute ischemic stroke patients treated with IV rt-PA experience long-term clinical benefits in survival and functional status.

Retreatment Rates Among Endometriosis Patients Undergoing Hysterectomy or Laparoscopy.

BACKGROUND: Hysterectomy and laparoscopy are the two most common surgical options used to treat women with endometriosis, yet the disease may still recur. This study aimed to determine the long-term retreatment rates among endometriosis patients in the United States who received either hysterectomy or laparoscopy. MATERIALS AND METHODS: Patients aged 18-49 years with endometriosis who underwent hysterectomy or laparoscopy were identified in the Truven Health MarketScan claims database (2004-2013). The retreatment rate up to 8 years after the initial surgery was estimated using Kaplan-Meier survival analysis. The relative risk of retreatment among patients with hysterectomy versus laparoscopy was assessed using a Cox proportional hazard model. RESULTS: A total of 24,915 patients with endometriosis who underwent hysterectomy and 37,308 patients with endometriosis who underwent laparoscopy were identified. The estimated retreatment rates were 3.3%, 4.7%, and 5.4% in the 2nd, 5th, and 8th year following hysterectomy, respectively, while the rates following laparoscopy were 15.8%, 27.5%, and 35.2%, respectively. The hazard ratio of retreatment was 0.157 (95% confidence interval [CI]: 0.146-0.169) comparing hysterectomy to laparoscopy. In the sensitivity analysis, which expanded the definition of retreatment by including medical treatments, the retreatment rate increased by a factor of 11-14 for the hysterectomy cohort and by a factor of 2-4 for the laparoscopy cohort, and the hazard ratio of retreatment rate for hysterectomy versus laparoscopy was 0.490 (95% CI: 0.477-0.502). CONCLUSIONS: Our study results indicated that the disease retreatment rate after laparoscopy is high among patients with endometriosis; even hysterectomy does not guarantee freedom from retreatment.

Comparative efficacy of long-acting ß2-agonists as monotherapy for chronic obstructive pulmonary disease: a network meta-analysis.

PURPOSE: Long-acting ß2-agonists (LABAs) have demonstrated efficacy in patients with COPD in clinical trials. The purpose of this study was to assess the comparative efficacy of all available dosages of all LABA monotherapies using a network meta-analysis. METHODS: A systematic literature review identified 33 randomized controlled trials of LABA monotherapies (salmeterol 50 µg twice daily [BID]; formoterol 12 µg BID; indacaterol 75, 150, and 300 µg once daily [OD]; olodaterol 5 and 10 µg OD, and vilanterol 25 µg OD). Clinical efficacy was evaluated at 12 and 24 weeks in terms of trough forced expiratory volume in 1 second (FEV1), transition dyspnea index focal score, St George's Respiratory Questionnaire total score, and rate of COPD exacerbations. The relative effectiveness of all LABA monotherapies was estimated by Bayesian network meta-analysis. RESULTS: At 12 and 24 weeks, indacaterol 300 and 150 µg OD were associated with statistically significant improvement in trough FEV1 compared to all other LABA monotherapies; vilanterol 25 µg OD was superior to formoterol 12 µg BID. At 12 weeks, indacaterol 75 µg OD was associated with significant improvement in trough FEV1 compared to formoterol 12 µg BID and olodaterol (5 and 10 µg OD); salmeterol 50 µg BID was superior to formoterol 12 µg BID and olodaterol 5 µg OD. Indacaterol 300 µg OD was also associated with significant improvement in transition dyspnea index focal score compared to all other LABAs at 12 or 24 weeks. Indacaterol 150 µg OD had significantly better results in exacerbation rates than olodaterol 5 µg and olodaterol 10 µg OD. CONCLUSION: Indacaterol 300 µg, followed by 150 and 75 µg, were the most effective LABA monotherapies for moderate to severe COPD.

Economic Burden of Switching to a Non-Tumor Necrosis Factor Inhibitor Versus a Tumor Necrosis Factor Inhibitor Biologic Therapy among Patients with Rheumatoid Arthritis.

INTRODUCTION: The objective of this study was to examine healthcare resource utilization (HRU) and costs associated with switching to another tumor necrosis factor alpha inhibitor (TNFi) therapy versus a non-TNFi therapy among patients with rheumatoid arthritis (RA) discontinuing use of an initial TNFi biologic therapy. METHODS: Patients with ≥2 RA diagnoses who used ≥1 TNFi on or after their initial RA diagnosis were identified in a US employer-based insurance claims database. Patients were selected based on ≥1 claim of another TNFi or a non-TNFi biologic therapy (occurring after 2010, and within 30 days before to 60 days after discontinuation of the initial TNFi), and continuous insurance ≥6 months before (baseline period) and ≥12 months after the switch date (study period). Patient demographic and clinical characteristics were measured during the baseline period. All-cause and RA-related HRU and costs were analyzed during the 12-month study period using multivariable regression analysis controlling for baseline characteristics and selected comorbidities. RESULTS: Of the 1577 patients with RA that switched therapies, 1169 patients used another TNFi and 408 patients used a non-TNFi biologic. The most commonly used initial TNFi treatments were etanercept (50%) and adalimumab (34%) among the TNFi cohort, and infliximab (39%) and etanercept (28%) among the non-TNFi cohort. The TNFi cohort had significantly fewer outpatient visits [all-cause: 23.01 vs. 29.77 visits/patient/year; adjusted incidence rate ratio (IRR) = 0.78, P < 0.001; RA-related: 7.42 vs. 13.58; adjusted IRR = 0.58, P < 0.001] and rheumatologist visits (all-cause: 4.01 vs. 6.81; adjusted IRR = 0.66, P < 0.001; RA-related: 3.23 vs. 6.40; adjusted IRR = 0.58, P < 0.001) than the non-TNFi cohort. All-cause total costs were significantly lower for patients who switched to another TNFi instead of a non-TNFi therapy ($36,932 vs. $44,566; adjusted difference = $7045, P < 0.01), as were total RA-related costs ($26,973 vs. $31,735; adjusted difference = $4904, P < 0.01). CONCLUSION: Adult patients with RA discontinuing TNFi therapy who switched to an alternative TNFi incurred lower healthcare costs than patients who switched to a non-TNFi biologic. FUNDING: AbbVie, Inc.

The direct and indirect costs associated with endometriosis: a systematic literature review.

STUDY QUESTION: What is the economic burden of endometriosis? SUMMARY ANSWER: The identified studies indicate that there is a significant economic burden associated with endometriosis, as observed by both direct and indirect costs. WHAT IS KNOWN ALREADY: Two previous systematic literature reviews suggested that there were considerable direct costs associated with endometriosis and there was a general lack of measurement of indirect costs. STUDY DESIGN, SIZE, DURATION: We performed a systematic literature review. MEDLINE and EMBASE databases from 2000 to 2013 were searched. The literature search was limited to human studies of patients with endometriosis. Papers in languages other than English were excluded. PARTICIPANTS/MATERIALS, SETTING, METHODS: Studies reporting direct or indirect costs among patients with endometriosis were considered for inclusion. Direct costs included inpatient, outpatient, surgery, drug and other healthcare service cost. Indirect costs were related to absenteeism and presenteeism (lost productivity at work). MAIN RESULTS AND THE ROLE OF CHANCE: After evaluating the 1396 articles in the search results, 12 primary studies that reported direct or indirect costs associated with endometriosis were identified and included in the data extraction. Three of the studies were conducted in the USA, one study each was conducted in Austria, Belgium, Brazil, Canada, Finland, Germany and Italy, and two studies included data from 10 countries. Significant variability was observed in the reviewed studies in methodology, including data source, cost components considered and study perspective. Estimates of total direct costs ranged from $1109 per patient per year in Canada to $12 118 per patient per year in the USA. Indirect costs of endometriosis ranged from $3314 per patient per year in Austria to $15 737 per patient per year in the USA. LIMITATIONS, REASONS FOR CAUTION: The studies identified in the systematic literature review varied greatly by study methodology as well as by country owing to different healthcare systems and costs of healthcare services, which contributed to large variations in the direct and indirect cost estimates. WIDER IMPLICATIONS OF THE FINDINGS: A majority of the studies we found were published after the periods covered in the prior systematic literature reviews, which provided substantial contributions to an understanding of the economic burden of endometriosis, especially in the area of indirect costs. The long-term burden of endometriosis following diagnosis is still under-studied, which is a concern given the chronic nature of the disease and the substantial recurrence of endometriosis symptoms. STUDY FUNDING/COMPETING INTERESTS: This study was funded by AbbVie, which also develops the oral GnRH antagonist elagolix (in collaboration with Neurocrine Biosciences) for the management of endometriosis and uterine fibroids. A.M.S. is an employee of AbbVie and currently owns AbbVie stocks. H.Y., E.X.D. and C.K. are employees of Analysis Group, Inc., which has received consultancy fees from AbbVie. C.W. is a Clinical Professor at the Department Obstetrics and Gynecology at Georgetown University in Washington, DC, USA and has served in a consulting role to AbbVie for this project.

The direct and indirect costs of uterine fibroid tumors: a systematic review of the literature between 2000 and 2013.

This systematic literature review was conducted to summarize the direct and indirect costs per patient that are associated with uterine fibroid tumors in international studies. A search with predefined search terms was conducted in MEDLINE and EMBASE for studies that were published from January 2000 to November 2013. The review included primary studies that were in English and that reported either direct costs (drug costs, procedure costs, and medical service costs) or indirect costs (such as productivity loss) among patients with uterine fibroid tumors. A total of 26 studies that were identified and included in the data extraction included 19 studies in the United States, 2 studies in the Netherlands, 1 study each in Germany, China, Italy, and Canada, and 1 study reported data that were collected from 3 countries: Germany, France, and England. The studies differed substantially in perspectives that were adopted for analysis, research designs, data elements that were collected, setting, populations, and outcome measurements. Among 3 studies that reported total direct costs during the year after uterine fibroid tumor diagnosis, 2 studies reported an average of $9473 and $9319 per patient, respectively; 2 studies reported the excess costs over controls to be $6076 and $5427, respectively. The indirect costs per patient ranged from $2399-15,549, and the excess indirect cost per patient over control groups ranged from $323-4824 in the year after the diagnosis. The total costs, sum of direct and indirect costs, ranged from $11,717-25,023 per patient per year, after diagnosis or surgery among patients with uterine fibroid tumors. Compared with control subjects, the additional annual cost ranged from $2200-15,952 per patient. The results of this systematic literature review highlight the substantial direct and indirect costs that are associated with uterine fibroid tumors to health care payers and society. The large number and the variety of studies identified also emphasize the growing awareness of the significant economic impact of uterine fibroid tumors. Current gaps that were identified through this review warrant further investigation to elucidate fully the economic burden of uterine fibroid tumors, including, but not limited to, burden from the patient's perspective and the entirety of indirect costs.

Healthcare utilization and costs in women diagnosed with endometriosis before and after diagnosis: a longitudinal analysis of claims databases.

OBJECTIVE: To assess healthcare resource utilization and costs during the 5 years before and 5 years after diagnosis among women with endometriosis, in comparison with women without endometriosis. DESIGN: Longitudinal, retrospective, case-control study. SETTING: None. PATIENT(S): A total of 37,570 matched pairs of women with and without (controls) endometriosis were identified from the Truven Health MarketScan claims database (2000-2010). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Annual healthcare resource utilization and costs (in 2010 US dollars) were evaluated for the 5 years before and 5 years after diagnosis. RESULT(S): Mean patient age at index (first diagnosis) date was 36.4 years for endometriosis patients and controls. Endometriosis patients had a higher utilization of outpatient and emergency room services during each pre- and postindex year, and a higher utilization of inpatient services during the last preindex year and all 5 postindex years. Total costs were highest in the first postindex year for endometriosis patients, reaching $13,199, compared with $3,747 for controls. Annual costs were significantly higher for patients than controls during each pre- and postindex year; overall, the cost difference was $26,305 over 10 years: $7,028 in the 5 years before diagnosis and $19,277 in the 5 years after diagnosis. CONCLUSION(S): Endometriosis poses a significantly high economic burden, both before and after diagnosis. The highest resource utilization and costs experienced by endometriosis patients occur in the first year after diagnosis.

Treatment, monitoring, and economic outcomes of venous thromboembolism among hospitalized patients in China.

BACKGROUND: The prevalence of venous thromboembolism (VTE) has been increasing in China. However, the treatment pattern and economic burden of these patients have not been well-understood. OBJECTIVE: The objective of this study was to examine the patient characteristics, treatment pattern, anticoagulant monitoring, and economic burden of VTE among hospitalized patients in China. METHODS: Hospitalizations with a diagnosis of VTE [including deep vein thrombosis (DVT) or pulmonary embolism (PE)] between 1 January 2010 and 30 June 2013 were included. Descriptive analysis was conducted for patients' characteristics, anticoagulant treatment, international normalized ratio (INR) monitoring, and hospitalization cost [in 2013 Chinese yuan (Y) and US dollars (US$)]. Multivariate regressions were performed to assess factors associated with oral anticoagulant use and total costs of inpatient care. RESULTS: A total of 1,047 VTE-related hospitalizations were selected. The sample had a mean age of 62.4 years, with 45.9 % female. About 46.3 % of hospitalizations used heparin only, 35.0 % used warfarin, 0.8 % used rivaroxaban, and 18.0 % did not use anticoagulants. Among hospitalizations where warfarin was used, 90.8 % received at least one INR test and only 30 % had the last INR within the target therapeutic range (2-3) before discharge. The mean (standard deviation) total cost per hospitalization was Y29,114 (43,772) [US$4,757 (7,152)]. PE, VTE as primary diagnosis, female, insurance coverage, anticoagulant treatment, co-morbidities, admission condition, and surgical procedure were significantly associated with inpatient costs. CONCLUSIONS: Conventional anticoagulants were most commonly used in the study sample. Under-monitoring and suboptimal care may be an issue for patients treated with warfarin. The average total inpatient cost of VTE-related hospitalizations is high.