Comparison of prostate-specific antigen response in patients with metastatic castration-sensitive prostate cancer initiated on apalutamide or abiraterone acetate: A retrospective cohort study.

BACKGROUND: Deep prostate-specific antigen (PSA) response (≥90% reduction in PSA [PSA90]) is an important early response indicator of radiographic progression-free survival and overall survival in patients with metastatic castration-sensitive prostate cancer (mCSPC). This study compared PSA90 responses by 6 months between patients with mCSPC at first use of apalutamide or abiraterone acetate, both androgen receptor signaling inhibitors. METHODS: Clinical data from 77 community urology practices in the United States were analyzed. Patients with mCSPC were classified into treatment cohorts based on their first filled prescription (index date) for apalutamide or abiraterone acetate on or after September 17, 2019 (approval date of apalutamide for mCSPC). Patients were followed from the index date until the earliest of index treatment discontinuation, treatment switch, end of clinical activity, or end of data availability (September 17, 2021). Inverse probability of treatment weighting (IPTW) was used to ensure similarity in distribution of baseline characteristics between cohorts. PSA90 was defined as the earliest attainment of ≥90% reduction in PSA relative to baseline (most recent value within 13 weeks pre-index). Time to PSA90 between cohorts was compared by weighted Kaplan-Meier analysis and with Cox proportional hazards models. RESULTS: A total of 364 patients treated with apalutamide and 147 treated with abiraterone acetate met the study criteria. Patient characteristics were well balanced after IPTW. By 6 months post-index, patients initiated on apalutamide were 53% more likely to achieve PSA90 than those initiated on abiraterone acetate (P = 0.016). Similar results were observed by 9 and 12 months post-index (both P ≤ 0.019). The median time to PSA90 was 3.5 months for the apalutamide cohort and not reached for the abiraterone acetate cohort. CONCLUSIONS: In real-world patients with mCSPC, significantly more patients achieved PSA90 with apalutamide than with abiraterone acetate, and this response was achieved earlier with apalutamide.

Healthcare Resource Utilization and Costs in Patients with EGFR-Mutated Advanced Non-Small Cell Lung Cancer Receiving First-Line Treatment in the United States: An Insurance Claims-Based Descriptive Analysis.

BACKGROUND: An estimated 10-15% of non-small cell lung cancer (NSCLC) cases present with epidermal growth factor receptor mutation (EGFRm). While EGFR tyrosine kinase inhibitors (EGFR-TKIs) such as osimertinib have become first-line (1L) standard of care for these patients, limited chemotherapy use still occurs in real-world practice. Studies of healthcare resource use (HRU) and cost of care provide a means by which the value of various treatment regimens, healthcare efficiency, and disease burden can be assessed. These studies are important for population health decision makers and health systems that prioritize value-based care to drive population health. OBJECTIVE: The aim of this study was to descriptively assess HRU and costs among patients with EGFRm advanced NSCLC initiating 1L therapy in the United States. METHODS: IBM MarketScan Research Databases (January 1, 2017 to April 30, 2020) were used to identify adult patients with advanced NSCLC, based on a diagnosis for lung cancer (LC) and initiation of 1L therapy or diagnosis of metastases within 30 days of the first LC diagnosis. All patients had ≥ 12 months of continuous insurance eligibility prior to the first LC diagnosis and initiated (in 2018 or after) an EGFR-TKI during any line of therapy to proxy EGFRm status. Per-patient-per-month all-cause HRU and costs were described during 1L for patients initiating 1L osimertinib or chemotherapy. RESULTS: A total of 213 patients with advanced EGFRm NSCLC were identified (mean age at 1L initiation: 60.9 years; 69.0% female). In 1L, 66.2% initiated osimertinib, 21.1% chemotherapy, and 12.7% another regimen. Mean 1L therapy duration was 8.8 months (osimertinib) and 7.6 months (chemotherapy), respectively. Among osimertinib recipients, 28% had an inpatient admission, 40% an emergency room (ER) visit, and 99% an outpatient visit. Among chemotherapy recipients, these proportions were 22%, 31%, and 100%. Mean monthly all-cause healthcare costs among osimertinib and chemotherapy patients were US$27,174 and US$23,343, respectively. Among osimertinib recipients, drug-related costs (including pharmacy and outpatient antineoplastic drug and administration costs) made up 61% (US$16,673) of total costs, inpatient costs 20% (US$5462), and other outpatient costs 16% (US$4432). In chemotherapy recipients, 59% (US$13,883) of total costs were drug-related, 5% (US$1166) were inpatient costs, and 33% (US$7734) other outpatient costs. CONCLUSIONS: Higher mean total cost of care was observed among patients receiving 1L TKI (osimertinib) than 1L chemotherapy in EGFRm advanced NSCLC. However, descriptive differences in type of spending and HRU were identified: higher inpatient costs and inpatient days for osimertinib versus higher outpatient costs for chemotherapy. Findings suggest that significant unmet needs may remain for 1L treatment of EGFRm NSCLC, and despite significant advances in targeted care, further individualized therapies are needed to balance benefits, risks, and total cost of care. Furthermore, observed descriptive differences in inpatient admissions may have implications for quality of care and patient quality of life, for which additional research is warranted.

Attainment of early, deep prostate-specific antigen response in metastatic castration-sensitive prostate cancer: A comparison of patients initiated on apalutamide or enzalutamide.

BACKGROUND: Deep prostate-specific antigen (PSA) response, defined as a ≥90% decline in PSA (PSA90), is an important early response indicator for achieving radiographic progression-free and overall survival in patients with metastatic castration-sensitive prostate cancer (mCSPC) treated with a next-generation androgen signaling inhibitor (ASI), such as apalutamide or enzalutamide. The objective of this study was to compare deep PSA response among patients with mCSPC newly initiated on apalutamide or enzalutamide. METHODS: Clinical data from 69 community urology practices in the United States were evaluated. Patients with mCSPC were classified into cohorts based on their first dispensation (index date) for apalutamide or enzalutamide and were followed until the earliest of treatment discontinuation, initiation of a new next-generation androgen receptor signaling inhibitor, end of clinical activity (including death), or end of data availability (03/05/2021). Inverse probability of treatment weights (IPTW) were used to reduce baseline confounding. PSA90 was defined as the earliest ≥90% PSA decline relative to baseline PSA. The proportion of patients achieving PSA90 and time to PSA90 were reported using weighted Kaplan-Meier analysis and weighted Cox proportional hazards models, respectively. RESULTS: The apalutamide and enzalutamide cohorts comprised 186 and 165 patients, respectively. Patient characteristics were generally well balanced after IPTW. By 6 months, patients initiated on apalutamide had a 56% greater likelihood of attaining PSA90 than those initiated on enzalutamide (P = 0.014). This result remained significant through the end of the observation period. The median time to achieving PSA90 was 3.1 months with apalutamide and 5.2 months with enzalutamide. CONCLUSIONS: This real-world study demonstrated that apalutamide initiation is associated with a significantly higher likelihood of achieving ≥90% reduction in PSA as compared to initiation of enzalutamide. Moreover, this deep PSA response was observed to occur earlier with apalutamide treatment than with enzalutamide.

Early prostate-specific antigen response among Black and non-Black patients with advanced prostate cancer treated with apalutamide.

Aim: To assess reduction in prostate-specific antigen (PSA) levels among Black and non-Black patients treated with apalutamide for non-metastatic castration-resistant prostate cancer (nmCRPC) or metastatic castration-sensitive prostate cancer (mCSPC). Patients & methods: Patients were identified from electronic medical data. PSA reduction (≥50%, ≥90% or below 0.2 ng/ml) after apalutamide initiation was assessed. Results: A total of 313 patients with nmCRPC and 260 patients with mCSPC were identified. The majority of patients treated with apalutamide achieved a 90% reduction in PSA regardless of indication or race. The proportion of patients achieving a PSA reduction at any level was similar among Black and non-Black patients and was consistent with apalutamide phase III trials. Conclusion: In routine clinical practice, apalutamide consistently produced reduction in PSA levels in Black and non-Black men with nmCRPC or mCSPC.

Real-World Prostate-Specific Antigen Response and Treatment Adherence of Apalutamide in Patients With Non-Metastatic Castration-Resistant Prostate Cancer.

OBJECTIVE: To describe prostate-specific antigen (PSA) response and treatment adherence, overall and stratified by race, for patients with non-metastatic castration-resistant prostate cancer (nmCRPC) treated with apalutamide. METHODS: Electronic medical records representing 63 urology practices from the United States were used to conduct this study. Patients with ≥2 apalutamide prescription fills and ≥12 months of prior prostate cancer management were identified. Patients were followed from apalutamide initiation until a switch to another antineoplastic treatment, death, or end of data availability (October 4, 2019). PSA response (≥50% decline from baseline PSA) and apalutamide adherence rates are described for the overall nmCRPC population treated and also stratified by race (Black and non-Black cohorts). RESULTS: Overall, 193 patients with nmCRPC were initiated on apalutamide. Thirty-three patients were Black (17.1%), 138 were non-Black (71.5%), and the remaining had an unknown racial background. The mean baseline PSA level for the overall, Black, and non-Black cohorts, was 7.0 ng/mL, 10.5 ng/mL, and 5.6 ng/mL, respectively. At 12 months of follow-up, PSA response was 86.0%, 93.1%, and 85.9% for the overall, Black, and non-Black cohorts, respectively. During a mean follow-up period of 333 days, 352 days, and 326 days, adherence was 93.6%, 90.1%, and 94.5% for the overall, Black and non-Black cohorts, respectively. CONCLUSION: This real-world study of patients with nmCRPC initiated on apalutamide showed that PSA response was robust and consistent with clinical trial data. Moreover, both Black and non-Black patients demonstrated high treatment adherence.

Medication adherence among patients with advanced prostate cancer using oral therapies.

Aims: In light of the extended overall survival and improved quality of life provided by advanced prostate cancer (PC) oral therapies, this study aimed to describe treatment adherence to advanced PC oral therapies and evaluate associated patient characteristics and subsequent healthcare resource utilization (HRU). Patients & methods: Patients with advanced PC initiating apalutamide, enzalutamide or abiraterone acetate were identified from administrative data (October 1, 2014-September 30, 2019). Adherence and persistence at six months postinitiation were used to evaluate patient factors and HRU. Results: Aged ≥75 years, Black race, chemotherapy use and higher pharmacy paid amounts were associated with poor adherence/persistence, which translated to higher HRU. Conclusions: Strategies to increase adherence and persistence may improve patient outcomes and associated HRU.

Lay abstract This study included 27,262 patients with advanced prostate cancer who started taking one of three oral cancer medications (apalutamide, enzalutamide or abiraterone acetate) between October 2014 and September 2019. Patients who were black, aged 75 years or older, who had chemotherapy or who had higher prescription costs had the most difficulty following dosing guidelines or staying on treatment. Patients who did not follow dosing guidelines required more healthcare services. In light of the extended survival and improved quality of life that oral cancer medication for advanced prostate cancer provides, helping patients to take the correct medication dose, at the right time, and for the recommended length of time may improve their outcomes and reduce medical costs.

Healthcare resource utilization and costs associated with inflammatory bowel disease among patients with chronic inflammatory diseases: a retrospective cohort study.

BACKGROUND: Chronic inflammatory diseases (CIDs; ankylosing spondylitis [AS], psoriatic arthritis [PsA], psoriasis [PsO], or rheumatoid arthritis [RA]) and inflammatory bowel disease (IBD; Crohn's disease and ulcerative colitis) are associated with substantial economic burden. The relative increased costs among patients with CIDs and concomitant IBD compared to those without IBD is an important consideration when deciding on the clinical management of patient symptoms. Given the increasing use of novel agents for the treatment of CIDs, including those that may increase the risk of IBD in patients with CIDs, the objective of the study was to describe the incidence of IBD and to quantify healthcare resource utilization (HRU) and costs associated with IBD among patients with CIDs. METHODS: The IBM MarketScan® Research Databases (1/2010-7/2017) were used to identify adult patients with ≥2 claims with a diagnosis of either AS/PsA/PsO/RA (index date was a random claim for AS/PsA/PsO/RA). The one-year incidence rate of IBD was calculated following the index date. HRU and healthcare costs were compared between patients developing and not developing IBD in the year following the index date, adjusting for baseline characteristics. RESULTS: A total of 537,450 patients with CIDs (mean age = 54.0 years; 63.1% female) were included in the study. The 1-year incidence rate of IBD was 0.52% (range = 0.39% in patients with PsO but without PsA to 1.73% in patients with AS). Patients who developed IBD (N = 2778) had significantly higher rates of inpatient, outpatient, and emergency room visits (incidence rate ratios [IRR] = 2.91, 1.35, 1.81; all P < 0.0001), compared to patients without IBD (N = 534,672). Patients who developed IBD had $18,500 (P < 0.0001) higher total costs per year, including $15,121 (P < 0.0001) higher medical costs and $3380 higher pharmacy costs (P < 0.0001). CONCLUSION: Higher HRU and costs were observed in patients with concomitant CID and IBD compared to patients with CID alone. Consideration should be given to treatment decisions that adequately manage CID and IBD to ensure optimal clinical and economic outcomes.

Outcomes of infliximab dose escalation in patients with rheumatoid arthritis.

INTRODUCTION: Dose escalation of infliximab in both primary and secondary nonresponders is widely reported; however, the usefulness of dose escalation has been disputed. The objective of this analysis is to evaluate trends in clinical efficacy following multiple infliximab dose escalations in patients with rheumatoid arthritis (RA). METHODS: Patients enrolled in a US RA registry were included if they initiated infliximab at 3 mg/kg every 8 weeks, received ≥ 1 infliximab dose escalation within 12 months of initiation, and had ≥ 1 visit following dose escalation. Trends in mean Clinical Disease Activity Index (CDAI) and Health Assessment Questionnaire (HAQ) scores from visits following dose escalations were evaluated. RESULTS: In patients who received 2 or 3 dose escalations, the initial (1 or 2) dose escalations resulted in reduced mean CDAI scores, but subsequent escalations did not further reduce disease activity. In patients who received ≥ 4 dose escalations, mean CDAI scores did not further reduce disease activity over time. Mean HAQ scores were stable over time in patients who received 2 or 3 dose escalations. In patients who received ≥ 4 dose escalations, mean HAQ scores decreased following 1 dose escalation but progressively increased following subsequent dose escalations. CONCLUSION: Initial dose escalations (from 3 mg/kg to the equivalent of approximately 5 to 7 mg/kg) may be useful in controlling disease activity; however, there may be diminishing clinical benefit of further escalations, which can also increase the potential risk for infection and increase incremental drug costs. KEY POINTS: • Initial infliximab dose escalations (1 to 2) may be useful in lowering disease activity in patients with rheumatoid arthritis. • There does not appear to be a clinical benefit in infliximab dose escalations above the equivalent of 5 to 7 mg/kg.

Health Care Resource Utilization and Costs Associated With Switching Biologics in Rheumatoid Arthritis.

PURPOSE: Although biologics are effective in managing rheumatoid arthritis (RA), many patients experience at least one biologic switch during treatment. A switch in biologic treatment can occur for medical or nonmedical reasons. Changes to treatment regimens, even in patients previously stable on therapy, can have clinical and cost implications. This study examined health care resource use and costs incurred with switching from an anti-tumor necrosis factor (TNF) medication in a population of patients with RA. METHODS: A retrospective analysis of patients with RA identified in Truven Commercial Claims and Encounters database (January 1, 2009, to December 13, 2013) was conducted. Patients were required to show evidence of new initiation of treatment with a biologic medication (index date) and continuous eligibility from 6 months before to 12 months after index. Patients were segmented into a continuous biologic group and a biologic switch group, the latter being further divided into switch from anti-TNF to anti-TNF (A-A subgroup) and switch from anti-TNF to a treatment with other mechanism of action (A-O subgroup). Means (SD) and medians of resource use and cost outcomes were calculated over the 12-month postindex period; multivariate models controlling for demographics, biologic switch, and preindex health, resource use, and costs were constructed. FINDINGS: The total sample comprised 18,070 patients, with 16,643 qualifying for the continuous group and 1427 qualifying for the overall switch group. The overall switch group was more likely to utilize physician office, emergency department, and pharmacy services compared to the continuous group. Consequently, the overall switch group incurred greater total health care costs compared to the continuous group ($41,482 vs $36,557 per patient per annum; p < 0.05). Within the switch group, the A-O subgroup had significantly greater outpatient, medical, and total health care expenditures compared to those in the A-A subgroup. Regression analyses revealed that increased baseline utilization and costs, worse health, and older age were associated with increased utilization and costs over the follow-up period. Switching of biologics was associated with an approximate increase of US $4000 per patient per annum in total health care costs. IMPLICATIONS: These findings suggest that switching biologic agents in patients with RA may be accompanied by increased total health care costs. Efforts to optimize patient response to initial biologic therapy and to reduce unnecessary switching, such as for nonmedical reasons, may help to mitigate these costs.

Analysis of real-world treatment patterns in a matched rheumatology population that continued innovator infliximab therapy or switched to biosimilar infliximab.

PURPOSE: This study compared treatment patterns of Turkish patients with a diagnosis of rheumatoid arthritis (RA) who were treated with innovator Remicade® (infliximab [IFX]) and either continued IFX or switched to CT-P13. MATERIALS AND METHODS: Adult RA patients with ≥1 IFX claim were identified from the Turkish Ministry of Health database. Eligible patients initiated and continued IFX treatment (continuers cohort [CC]) or initiated IFX and switched to CT-P13 (switchers cohort [SC]) during the study period. The initial IFX claim date was defined as the index date. The switch/reference date was defined as the CT-P13 switch date for the SC or a random IFX date during the period of CT-P13 availability for the CC. Cohorts were matched by age, sex, and number of IFX prescriptions during baseline. Patient demographics, discontinuation, and switching were summarized. The baseline period was defined as the period from the index date to the switch/reference date. The follow-up period ranged from the switch/reference date to the end of data availability. RESULTS: After matching, 697 patients were selected: 605 patients for the CC and 92 patients for the SC. Mean IFX duration for the baseline period was 422 days in the CC and 438 days in the SC. Median time on any infused tumor necrosis factor (TNF) antagonist therapy was 1,080 days in the CC and 540 days in the SC during the study period. During the follow-up period, discontinuation was lower in the CC (CC=33.9% vs SC=87.5%; P<0.001). The mean time to discontinuation was longer in the CC (CC=276 days vs SC=132 days; P<0.001). A switch to another biologic medication during the follow-up period was observed in 19.0% of patients in the CC (n=115) and 81.5% of patients in the SC (n=75; P<0.001). CONCLUSION: Treatment patterns differed between patients prescribed IFX and CT-P13. In Turkey, RA patients maintained on IFX had greater treatment persistence (ie, fewer and later discontinuations) than those who initiated IFX and switched to CT-P13.

Satisfaction with Subcutaneous Golimumab and its Auto-Injector among Rheumatoid Arthritis Patients with Inadequate Response to Adalimumab or Etanercept.

BACKGROUND: Patient perceptions of treatment success, including satisfaction/preference, may complement clinical efficacy assessments. OBJECTIVE: Our objective was to evaluate satisfaction with subcutaneous golimumab and its auto-injector in patients with rheumatoid arthritis (RA) and an inadequate adalimumab/etanercept response. METHODS: In the multicenter, assessor-blinded GO-SAVE study, 433 patients with active RA (28-joint Disease Activity Score incorporating erythrocyte sedimentation rate [DAS28-ESR] ≥ 3.6 and six or more swollen and six or more tender joints) despite methotrexate and past adalimumab/etanercept treatment received open-label subcutaneous golimumab 50 mg every 4 weeks (q4w) through week 12. Week 16 responders (DAS28-ESR improvement from baseline > 1.2 and score ≤ 3.2) continued therapy through week 52; nonresponders were randomized (1:2) to double-blind subcutaneous golimumab 50 mg q4w or intravenous golimumab 2 mg/kg [weeks 16, 20, every 8 weeks (q8w)]. Patients rated satisfaction with their injection experience on a 5-point scale (1 = very dissatisfied; 5 = very satisfied) at screening, week 8 (all enrolled patients), and week 44 (for patients continuing open-label subcutaneous golimumab 50 mg q4w). Discomfort, pain, stinging, burning, and redness related to injection were assessed (none, mild, moderate, severe). RESULTS: Similar proportions of patients (N = 433) had most recently received adalimumab (50.3%) or etanercept (49.7%) prior to golimumab. Overall satisfaction (somewhat/very) with the golimumab injection experience was reported by 84.4% of patients at week 8 versus 63.4% of patients who were satisfied with prior adalimumab/etanercept. Patients receiving open-label subcutaneous golimumab through week 44 (N = 75) reported much less discomfort (60.9%), redness (60.9%), pain (59.4%), stinging (67.2%), and burning (65.6%) with the golimumab injection than with their previous tumor necrosis factor antagonist medication injection. CONCLUSION: Most patients with RA receiving golimumab following adalimumab/etanercept inadequate response were satisfied with their overall golimumab experience, including its auto-injector versus their previous injection device. CLINICAL TRIALS.GOV: NCT01004432; EudraCT 2009-010582-23.

Medication Adherence, Treatment Patterns, and Dose Reduction in Patients with Metastatic Castration-Resistant Prostate Cancer Receiving Abiraterone Acetate or Enzalutamide.

BACKGROUND: The efficacy of and overall survival associated with metastatic castration-resistant prostate cancer (CRPC) treatments rely on patients' consistent adherence to the recommended dosage regimens. OBJECTIVES: To evaluate treatment patterns and patient adherence to abiraterone acetate or enzalutamide therapy in real-world practice, and to examine the factors that may be associated with medication dose reduction in patients with metastatic CRPC. METHODS: Retrospective analyses were conducted using the Truven Health MarketScan research databases among patients with metastatic CRPC who initiated treatment with abiraterone acetate or enzalutamide between October 1, 2012, and December 31, 2014 (index date). The patients were followed for up to 12 months, and their baseline characteristics were assessed during the 6 months before the index date. Medication adherence was measured at 3, 6, 9, and 12 months postindex using medication possession ratios (MPRs), and dose reduction was measured using refill gaps and relative dose intensity over the entire observation period. Kaplan-Meier survival analyses and Cox proportional hazards models were used to assess the association between the initial treatment and the risk for dose reduction. RESULTS: The study included 2591 and 807 patients who initiated treatment with abiraterone acetate and enzalutamide, respectively. At 6, 9, and 12 months postindex, the patients who initiated abiraterone acetate had higher MPRs than the patients who initiated enzalutamide. In addition, the patients who initiated abiraterone acetate had lower Kaplan-Meier rates of dose reduction across 4 measurements for dose reduction. All hazard ratios for treatment (abiraterone acetate vs enzalutamide) were significantly lower than 1 (range, 0.57-0.80), indicating a lower risk for dose reduction associated with abiraterone acetate. CONCLUSION: Patients who initiated abiraterone acetate therapy had higher medication adherence and lower risk for dose reduction than those who initiated enzalutamide therapy. Improved medication adherence may be associated with longer duration of treatment, which in turn may lead to better survival. Further research is needed to assess the potential effect of medication adherence on the overall survival of patients with metastatic CRPC.

Assessment of Real-World Central Nervous System Events in Patients with Advanced Prostate Cancer Using Abiraterone Acetate, Bicalutamide, Enzalutamide, or Chemotherapy.

BACKGROUND: Central nervous system (CNS) events are frequently reported among patients with advanced prostate cancer as a consequence of the treatments used in this patient population. OBJECTIVE: To assess the incidence of CNS events in patients with advanced prostate cancer who initiated treatment with abiraterone acetate, bicalutamide, enzalutamide, or chemotherapy. METHODS: The Truven Health MarketScan Research databases were used to retrospectively identify patients with prostate cancer who initiated treatment with abiraterone acetate, enzalutamide, bicalutamide, or chemotherapy after September 1, 2012 (ie, the index date). The chemotherapy agents included cabazitaxel, docetaxel, mitoxantrone hydrochloride, and estramustine, and were used as monotherapy or as combination therapy. Patients were followed until December 31, 2014, the end of exposure to treatment, or until loss to follow-up. Kaplan-Meier rates and adjusted Cox proportional hazard models were used to compare the incidence of CNS events between the abiraterone acetate cohort and the other cohorts. A sensitivity analysis of patients with a diagnosis of metastasis was also conducted. RESULTS: A total of 1067 patients receiving abiraterone acetate, 5524 receiving bicalutamide, 592 receiving enzalutamide, and 256 receiving chemotherapy were identified. After 12 months, patients who received abiraterone acetate were less likely to have a CNS event than patients who received enzalutamide (39.5% vs 46.0%, respectively; P = .0036) or chemotherapy (39.5% vs 51.1%, respectively; P = .0277), and were more likely to have a CNS event than patients who received bicalutamide (39.5% vs 34.2%, respectively; P = .0397). After multivariate adjustment, at 12 months, patients who initiated abiraterone acetate treatment had 20% (P = .0388) reduction in the risk for a CNS event compared with patients who initiated enzalutamide; 8% (P = .3622) versus bicalutamide; and 27% (P = .0456) versus chemotherapy. The sensitivity analysis yielded similar results. CONCLUSION: The results of this large observational study suggest that among patients with metastatic prostate cancer, treatment with abiraterone acetate is associated with a significantly lower likelihood of having a CNS event compared with treatment with enzalutamide or chemotherapy, but not with bicalutamide, even when controlling for metastatic disease.

Duration of Treatment in Prostate Cancer Patients Treated with Abiraterone Acetate or Enzalutamide.

BACKGROUND: Abiraterone acetate (AA) and enzalutamide (ENZ) are oral therapies offering survival benefit to metastatic castration-resistant prostate cancer (mCRPC) patients. Despite the availability of multiple treatment options for mCRPC, there is a lack of information on the effect that being initiated on AA or ENZ has on the combined prostate cancer treatment duration. OBJECTIVE: To compare the combined duration of prostate cancer treatments of patients initiated on AA with that of patients initiated on ENZ. METHODS: Truven Health MarketScan Research Databases from March 2012 to December 2014 were used to identify males with prostate cancer initiated on AA or ENZ (index therapy). Baseline characteristics were assessed during the 6 months pre-index. Inverse probability of treatment weights (IPTWs) were used to reduce baseline confounding. Treatment duration spanned from the index date to the earliest of treatment discontinuation (defined as a > 60-day gap in treatment), 24 months post-index, health plan disenrollment, or end of data. Weighted Kaplan-Meier and Cox proportional hazard models were used to compare the combined duration of mCRPC treatments (AA, ENZ, chemotherapy, sipuleucel-T, and radium 223) and any prostate cancer treatments (mCRPC, hormonal, and corticosteroid treatments) between patients initiated on either AA or ENZ. RESULTS: A total of 2,591 patients initiated on AA and 807 patients initiated on ENZ were selected for the study. Patients' characteristics were generally well balanced after IPTW. At 3 months, patients initiated on AA were associated with fewer discontinuations of mCRPC treatments (hazard ratio [HR] = 0.73, P = 0.004) or of any prostate cancer treatments (HR = 0.61, P = 0.002), compared with patients initiated on ENZ. This result was maintained at 6, 9, 12, 18, and 24 months for mCRPC treatments (HR = 0.75, P < 0.001) and for any prostate cancer treatments (HR = 0.69, P < 0.001). Median duration of mCRPC treatments was 4.1 months longer for patients initiated on AA compared with those initiated on ENZ (18.3 vs. 14.2 months, P < 0.001) and similarly, the median duration of any prostate cancer treatment was longer for patients initiated on AA compared with those initiated on ENZ (not reached vs. 22.2 months, P < 0.001). CONCLUSIONS: In this study, patients initiated on AA, compared with those initiated on ENZ, had a longer combined duration of mCRPC or prostate cancer treatments. DISCLOSURES: This research was funded by Janssen Scientific Affairs. Pilon, Emond, and Lefebvre are employees of Analysis Group, a consulting company that has received research grants from Janssen Scientific Affairs. Behl and Ellis are employees of Janssen Scientific Affairs and stockholders in Johnson & Johnson. Dawson is on the speakers bureau for Janssen, Astellas, and Sanofi Aventis. Emond reports grants from Regeneron, Bristol-Myers Squibb, GlaxoSmithKline, Aegerion, Bayer, Novartis, Allergan, Millenium, and Genentech. Pilon reports grants from Novartis, GlaxoSmithKline, Pfizer, and Bayer. Lefebvre reports grants from GlaxoSmithKline, Novartis, Bayer, Medtronic, Noven, and Novo Nordisk. Study concept and design were contributed primarily by Pilon and Lefebvre, along with the other authors. Pilon, Emond, and Lefebre collected the data, and data interpretation was performed by Behl, Lefebvre, and Dawson, along with Pilon, Ellis, and Emond, The manuscript was written by Pilon, Emond, and Lefebvre and revised by Behl, Ellis, and Dawson.

Assessment of Evidence-Based Standards in the Treatment of Advanced Prostate Cancer in a Community Practice.

INTRODUCTION: Although the monitoring of patients with advanced prostate cancer is essential to optimize treatment, little is known about adherence to guidelines. In this study we compared testing practices at an integrated urology/radiation oncology group practice with evidence-based guidelines and best practices. METHODS: Electronic medical records up to December 2014 from the integrated urology/radiation oncology group practice were queried to identify patients who received androgen deprivation therapy and in whom advanced disease was staged as androgen deprivation therapy sensitive, subcastration resistant (incompletely defined probable castration resistant prostate cancer) or castration resistant after April 2011 and for 6 months or more. Frequency of prostate specific antigen and testosterone level testing as well as imaging (magnetic resonance imaging, computerized tomography, positron emission tomography/computerized tomography, bone scan or x-ray) was evaluated, and compared to national guidelines and best practices. RESULTS: Overall 346 patients with androgen deprivation therapy sensitive prostate cancer, 90 with subcastration resistant prostate cancer and 102 with castration resistant prostate cancer met the study inclusion criteria. On average, prostate specific antigen was tested every 4.7, 3.7 and 3.3 months for patients with androgen deprivation therapy sensitive disease, subcastration resistant prostate cancer and castration resistant prostate cancer, respectively, compared with the 3 to 12 months and 3 months recommendations of the National Comprehensive Cancer Network and RADAR (Prostate Cancer Radiographic Assessments for Detection of Advanced Recurrence) for patients with androgen deprivation therapy sensitive disease and nonmetastatic castration resistant prostate cancer, respectively. Testosterone levels were assessed within 6 months of classification for 23% and 46% of patients with subcastration resistant prostate cancer and castration resistant prostate cancer, respectively. Finally, 28% and 46% of patients with subcastration resistant prostate cancer and castration resistant prostate cancer, respectively, underwent some type of imaging within 6 months. CONCLUSIONS: This retrospective study of patients receiving androgen deprivation therapy at a particular integrated urology/radiation oncology group practice demonstrated adherence to prostate specific antigen best practices. However, there was some room for improvement in terms of testosterone testing and imaging.

Prescribing Patterns of Oral Antineoplastic Therapies Observed in the Treatment of Patients With Advanced Prostate Cancer Between 2012 and 2014: Results of an Oncology EMR Analysis.

PURPOSE: The purpose of this study was to examine, using a US electronic medical records (EMR) database, the clinical characteristics and real-world treatment sequences in men with advanced prostate cancer who initiated treatment with abiraterone acetate or enzalutamide. METHODS: This retrospective, observational study evaluated adult male patients with a diagnosis of prostate cancer (International Classification of Diseases, Ninth Revision, Clinical Modification code 185) in the EMR database between July 1, 2011, and March 31, 2014, who had initiated first-line treatment with abiraterone acetate or enzalutamide between September 1, 2012, and March 31, 2014. The first record for a patient initiating abiraterone acetate or enzalutamide was the index date. Patients had 6 months of pre-index medical record history and a variable length follow-up period, extending from the index date to the end of medical record data availability or date of the end of the study (March 31, 2014). The sequence of first- and second-line therapies for advanced prostate cancer therapy was reported. FINDINGS: A total of 809 patients met study inclusion and exclusion criteria. This study found that the majority of patients who initiated treatment with either abiraterone acetate or enzalutamide between September 1, 2012, and March 31, 2014, received a single line of therapy (72%); abiraterone acetate was the most common first-line treatment (74% of first-line patients). A subset of patients treated first-line with either abiraterone acetate or enzalutamide were transitioned to an oral second-line agent (17% of first-line abiraterone acetate-treated patients transitioned to second-line enzalutamide, and 16% of first-line enzalutamide-treated patients transitioned to second-line abiraterone acetate). Chemotherapy with docetaxel was also a commonly observed second-line treatment selection, occurring in 8% of first-line abiraterone acetate-treated patients and in 7% of first-line enzalutamide-treated patients. IMPLICATIONS: This EMR study is among the first to present evidence of US physician practice prescribing patterns regarding initiation of oral antineoplastic agents and use of subsequent therapies in patients with advanced prostate cancer.

Cost per median overall survival month associated with abiraterone acetate and enzalutamide for treatment of patients with metastatic castration-resistant prostate cancer.

OBJECTIVE: To calculate costs per median overall survival (OS) month in chemotherapy-naïve patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone acetate plus prednisone (AA + P) or enzalutamide. METHODS: Median treatment duration and median OS data from published Phase 3 clinical trials and prescribing information were used to calculate costs per median OS month based on wholesale acquisition costs (WACs) for patients with mCRPC treated with AA + P or enzalutamide. Sensitivity analyses were performed to understand how variations in treatment duration and treatment-related monitoring recommendations influenced cost per median OS month. Cost-effectiveness estimates of other Phase 3 trial outcomes were also explored: cost per month of chemotherapy avoided and per median radiographic progression-free survival (rPFS) month. RESULTS: The results demonstrated that AA + P has a lower cost per median OS month than enzalutamide ($3231 vs 4512; 28% reduction), based on the following assumptions: median treatment duration of 14 months for AA + P and 18 months for enzalutamide, median OS of 34.7 months for AA + P and 35.3 months for enzalutamide, and WAC per 30-day supply of $8007.17 for AA + P vs $8847.98 for enzalutamide. Sensitivity analyses showed that accounting for recommended treatment-related monitoring costs or assuming identical treatment durations for AA + P and enzalutamide (18 months) resulted in costs per median OS month 8-27% lower for AA + P than for enzalutamide. Costs per month of chemotherapy avoided were $4448 for AA + P and $5688 for enzalutamide, while costs per month to achieve median rPFS were $6794 for AA + P and $7963 for enzalutamide. CONCLUSIONS: This cost-effectiveness analysis demonstrated that costs per median OS month, along with costs of other Phase 3 trial outcomes, were lower for AA + P than for enzalutamide. The findings were robust to sensitivity analyses. These results have important implications for population health decision-makers evaluating the relative value of therapies for mCRPC patients.

Treatment Sequences and Pharmacy Costs of 2 New Therapies for Metastatic Castration-Resistant Prostate Cancer.

BACKGROUND: The approval of new therapies for metastatic castration-resistant prostate cancer (mCRPC), including the oral agents abiraterone acetate and enzalutamide, has altered the standard of care for patients with mCRPC. Little information exists regarding the sequences in which new therapies for mCRPC with evidence of survival benefits are used. OBJECTIVE: To describe the sequence of medication use for patients with mCRPC as observed in 3 healthcare data sets. METHODS: Three healthcare claims data sets were used to identify patients with mCRPC who had no previous use of and were newly initiating 1 of the 2 oral study drugs (ie, abiraterone acetate or enzalutamide). The index date was the first study drug claim after September 1, 2012. Patients were followed until the data cutoff or until being lost to follow-up. Descriptive statistics summarized the proportion of patients receiving 1 line of therapy versus ≥2 lines of therapy. The use of a corticosteroid and the mean monthly pharmacy costs of abiraterone acetate or enzalutamide during the follow-up period were compared between the cohorts. RESULTS: A total of 3525 patients with mCRPC were identified from data set 1, 499 patients from data set 2, and 1949 patients from data set 3. The first-line use of abiraterone acetate was observed in 74%, 82%, and 80% of data sets 1, 2, and 3, respectively, and the first-line use of enzalutamide was seen in 26%, 18%, and 20%, respectively, of these same populations. The concomitant use of corticosteroids was observed in patients receiving first-line abiraterone acetate and in patients receiving first-line enzalutamide in all 3 data sets. After September 2012, abiraterone acetate was the most frequently administered therapy for mCRPC among the 2 oral agents, abiraterone acetate and enzalutamide. The monthly pharmacy costs associated with abiraterone acetate were significantly lower than those associated with enzalutamide in all 3 data sets. CONCLUSIONS: Based on the data used in this study, abiraterone acetate was more frequently administered for patients with mCRPC than enzalutamide. The concomitant use of corticosteroids was common in patients receiving first-line abiraterone acetate or first-line enzalutamide therapy. Patients receiving abiraterone acetate had significantly lower monthly pharmacy costs than patients receiving enzalutamide. These findings may facilitate the estimation of the budgetary impact of a treatment mix for population health and for managed care stakeholders.

Adherence patterns for abiraterone acetate and concomitant prednisone use in patients with prostate cancer.

BACKGROUND: With the growing use of oral anticancer medications, understanding adherence patterns has become increasingly important. Abiraterone acetate (AA) is a prodrug of abiraterone, a novel androgen biosynthesis inhibitor. AA is approved for use in combination with prednisone for treatment of patients with metastatic castration-resistant prostate cancer. OBJECTIVE: To evaluate AA and concomitant prednisone utilization and adherence patterns for patients with prostate cancer in the United States. METHODS: This study used data from 2 administrative health care claims databases--Dataset 1: Truven Health Analytics MarketScan (December 2010 to August 2012) and Dataset 2: Symphony Health Solutions' ProMetis Lx (June 2009 to March 2013). To evaluate the consistency of medication-taking behavior, adherence was measured using medication possession ratio (MPR), which was calculated as the sum of days of supply divided by the days on therapy in patients with at least 2 AA prescriptions. Additional outcomes included the proportion of patients taking prednisone, mean and median daily dose of AA, and concomitant prednisone use. Adherence was also studied by age, health care plan type, or previous recent chemotherapy subgroups. RESULTS: 515 patients (mean age: 72.2) and 3,228 patients (mean age: 72.2) with at least 1 AA claim were selected from Dataset 1 and Dataset 2, respectively. The mean (median) daily AA dose per person per prescription was 998.8 (1,000) mg for Dataset 1 and 994.2 (1,000) mg for Dataset 2, which is within 1% of the recommended daily dose (1,000 mg). Mean (median) MPR was 93% (98%; n = 492) in Study Population 1 and 93% (100%; n = 2,449) in Study Population 2. The mean (median) daily prednisone dose per person per prescription was similar in both datasets with 10.1 (10.0; n = 488) mg and 10.6 (10.0; n = 2,425) mg in Dataset 1 and 2, respectively. Similar adherence patterns were observed for patients in different age groups, for patients with commercial health care plans versus patients with Medicare coverage, and for patients with recent chemotherapy compared with patients without. CONCLUSIONS: Results from 2 observational studies reported high levels of adherence to AA dosing and administration patterns consistent with prescribing information. These findings provide useful insights into the treatment patterns in patients with prostate cancer treated with AA and can contribute to the current discussion in oncologic research and practice.