Tazemetostat in relapsed/refractory follicular lymphoma: a propensity score-matched analysis of E7438-G000-101 trial outcomes.

PURPOSE: In the tazemetostat E7438-G000-101 trial of relapsed/refractory (R/R) follicular lymphoma (FL), apparent superior efficacy was suggested for mutant-type (MT) EZH2 versus wild-type (WT) status. However, clinical disparities might have contributed to this conclusion. This study aimed to estimate outcomes after minimizing differences in baseline characteristics. METHODS: Propensity scores for each participant with WT (n = 54) and MT (n = 45) status were generated based on the likelihood of being selected given their baseline characteristics. Participants were matched using a 1:1 nearest-neighbor approach. RESULTS: The propensity-matched sample included 56 participants (28 WT, 28 MT). Objective response rates (95% confidence interval [CI]) were 35% (22-48) in WT and 69% (55-83) in MT prior to matching and 50% (31-69) in WT and 71% (54-88) in MT after matching. Median progression-free survival values (95% CI) were 11.1 (5.4-16.7) in WT and 13.8 months (11.1-22.1) in MT prior to matching and 14.3 (11.1-∞]) and 14.8 months (10.7-∞]) in WT and MT matched groups, respectively. CONCLUSIONS: This analysis suggests that efficacy outcomes for tazemetostat observed in participants with WT EZH2 R/R FL may have been similar to those in participants with MT had the 2 cohorts been more closely matched.

A Matching-Adjusted Indirect Comparison of Single-Arm Trials in Patients with Relapsed or Refractory Follicular Lymphoma Who Received at Least Two Prior Systemic Treatments: Tazemetostat was Associated with a Lower Risk for Safety Outcomes Versus the PI3-Kinase Inhibitors Idelalisib, Duvelisib, Copanlisib, and Umbralisib.

INTRODUCTION: Tazemetostat is an enhancer of zeste homolog 2 (EZH2) inhibitor recommended for patients with relapsed/refractory (R/R) follicular lymphoma (FL) after demonstrating single-agent, antitumor activity in patients with wild-type or mutant EZH2. The phosphoinositide 3-kinase (PI3K) inhibitors idelalisib, copanlisib, umbralisib and (formerly) duvelisib are indicated for third-line, fourth-line, and later (3L/4L+) treatment of R/R FL. The objective of this analysis was to provide an indirect treatment comparison of tazemetostat with each PI3K inhibitor for 3L/4L+ R/R FL treatment. METHODS: A systematic literature review was conducted to identify trials for idelalisib (DELTA), duvelisib (DYNAMO), copanlisib (CHRONOS-1 Part B), and umbralisib (UNITY-NHL) in 3L+ R/R FL. Matching-adjusted indirect comparisons were conducted by weighting tazemetostat individual patient data with available baseline characteristics from each comparator trial: age, Eastern Cooperative Oncology Group performance status, disease stage, histology, prior treatment lines, prior stem cell therapy, progression within 24 months, and refractory status to last therapy. Only the tazemetostat trial included patients with grade 3b or transformed FL, or recorded EZH2 mutation status. Primary safety outcomes included risk of grade ≥ 3 treatment-emergent adverse events (TEAEs); primary efficacy outcomes included objective response rate (ORR). RESULTS: Matched patients treated with tazemetostat had lower relative risk (RR) for all grouped safety outcomes, including any grade ≥ 3 TEAEs, compared with idelalisib (RR = 0.45), duvelisib (RR = 0.35), copanlisib (RR = 0.37), and umbralisib (RR = 0.65; all, p < 0.01), any serious TEAE, and any TEAE leading to dose reduction, drug discontinuation, or interruption. The ORR was not significantly different for tazemetostat versus other treatments (idelalisib 43% vs 56%, p = 0.16; duvelisib 48% vs 47%, p = 0.91; copanlisib 49% vs 61%, p = 0.11; and umbralisib 57% vs 47%, p = 0.10). CONCLUSIONS: In this statistically adjusted comparison, tazemetostat was associated with lower RR for safety outcomes versus idelalisib, duvelisib, copanlisib, and umbralisib, while achieving similar efficacy outcomes.

Burden of central nervous system complications in sickle cell disease: A systematic review and meta-analysis.

Sickle cell disease (SCD) patients are at high risk of central nervous system (CNS) complications and may experience significant morbidity. The study was conducted to describe the comprehensive burden of SCD-related CNS complications and to identify patient-reported outcome (PRO) instruments for future research. The review included 32 studies published from January 2000 to 2020, evaluating humanistic and economic outcomes. Twenty-three studies reported humanistic outcomes, 16 of which measured cognitive function using Wechsler Intelligence Scales. A meta-analysis was conducted, finding full-scale intelligence quotient (IQ) was significantly lower in: overt stroke versus controls: -12.6 (p < .001); silent cerebral infarct (SCI) versus controls: -5.7 (p < .001); overt stroke versus SCI: -9.4 (p = .008); and any event versus controls: -7.6 (p < .001). This review quantified the cognitive deficits associated with CNS complications in pediatric SCD populations and highlights the need for improved prevention/treatment. As PRO evidence was limited, we discussed areas for future research.

A systematic literature review of frequency of vaso-occlusive crises in sickle cell disease.

BACKGROUND AND PURPOSE: Sickle cell disease (SCD) is a collection of rare inherited blood disorders affecting approximately 100,000 people in the U.S. and 20-25 million people globally. Individuals with SCD experience recurrent episodes of severe and unpredictable pain that are caused by vaso-occlusive crises (VOCs), a hallmark of the disease. VOCs are the primary cause of hospitalization in SCD, result in missed workdays and school days, and decrease quality of life (QoL). Although VOCs cause significant burden in the lives of individuals with SCD, there is no synthesis on the frequency of VOCs in the real world. This systematic literature review sought to identify literature describing the frequency of VOCs experienced by individuals with SCD in real-world settings. METHODS: MEDLINE and 6 congresses were searched (date range: January 1, 2000 to June 30, 2020). Studies were reviewed independently by two researchers. Studies assessing frequency or prevalence of VOCs or VOC-related outcomes were included. RESULTS: Of 1438 studies identified in the search, 52 met pre-specified inclusion and exclusion criteria. Reported frequency of VOCs varied widely ranging from a mean or median of 0 VOCs/year to 18.2 VOCs/year. The proportion of patients experiencing ≥ 3 VOCs/year ranged from 4 to 67% and the proportion of patients experiencing ≥ 5 VOCs/year ranged from 18 to 59%. Measures of VOC severity were limited, with 13 studies considering frequency of complicated VOCs and only 1 study reporting duration of VOC episodes. CONCLUSIONS: This is the first study to systematically assess published evidence pertaining to VOCs in real-world settings. Reported VOC frequency in real-world settings varied widely, with a majority of studies only considering VOCs managed in an inpatient or outpatient setting. Studies that considered VOCs managed at home reported a higher frequency of VOCs, suggesting that many studies may underestimate the frequency of VOCs. This systematic literature review (SLR) highlights the need for consistent reporting of (1) self-reported VOCs, including those managed at home, (2) definitions of VOCs, (3) complicated VOCs, and (4) duration of VOC episodes in literature.

Cost-minimization analysis comparing eltrombopag vs romiplostim for adults with chronic immune thrombocytopenia.

BACKGROUND: Promacta (eltrombopag; EPAG) and Nplate (romiplostim; ROMI) have not been compared in head-to-head trials for treatment of chronic immune thrombocytopenia (cITP); however, indirect treatment comparisons have indicated similar efficacy and safety outcomes, and the drugs are generally accepted as therapeutic alternatives. OBJECTIVE: To determine which of the 2 therapies would result in the lowest overall cost from a US health plan perspective, under the assumption of equivalent clinical efficacy and safety. METHODS: A cost-minimization model was developed in Microsoft Excel. The model incorporated only costs that differ between the treatments, including drug acquisition, administration, and monitoring costs, over a 52-week horizon. Average dosing for EPAG and ROMI was taken from the long-term EXTEND trial and from a published metaanalysis of 14 clinical trials, respectively. ROMI is injectable and EPAG is oral, so only ROMI had administration costs. The model assumed patients used 25 mg EPAG tablets and the 250 µg vial size of ROMI. ROMI wastage was included in drug acquisition costs by rounding up average dose to the nearest whole vial. Monitoring requirements were determined from US prescribing information, with platelet monitoring assumed equal, and hepatic panel testing every 4 weeks for EPAG. The model was adjustable to commercial, Medicare, and Medicaid plan perspectives, with optional inclusion of drug wastage, monitoring, or administration costs. RESULTS: The base case used a commercial plan perspective, with average dosing of 51.5 mg/day for EPAG and 4.20 µg/kg/week for ROMI. The analysis found a cost difference per treated patient of $64,770 in favor of EPAG on an annual basis. Breakdown by unique costs for EPAG included drug-acquisition cost of $123,135 and monitoring cost of $705. Breakdown by unique costs for ROMI included drug-acquisition cost of $183,234, with wastage of $63,179 and administration cost of $5,377. Based on a hypothetical commercial plan with 1 million members and an estimated 11 patients with cITP receiving ROMI, potential annual savings for switching all patients from ROMI to EPAG is $712,473 or $0.06 per member per month. EPAG remained the less costly option for all plan types and assumptions. A sensitivity analysis found that the result was most sensitive to drug pricing and wastage inputs. CONCLUSIONS: Because of lower drug-acquisition costs (including drug wastage) and administration costs, treatment of cITP with EPAG is associated with a lower net cost per patient than ROMI. DISCLOSURES: This study was funded by Novartis Pharmaceuticals Corporation. Proudman, Lucas, and Nellesen are employees of Analysis Group, Inc., which received funding from Novartis Pharmaceuticals Corporation to conduct this study. Patwardhan was employed by Novartis Pharmaceuticals Corporation at the time of this study; Allen is an employee of Novartis. This research was presented as an e-poster at the AMCP 2020 Virtual, April 2020.

Financial Implications of Avapritinib for Treatment of Unresectable Gastrointestinal Stromal Tumors in Patients With a PDGFRA Exon 18 Variant or After 3 Previous Therapies in a Hypothetical US Health Plan.

Importance: With the approval of avapritinib for adults with unresectable or metastatic gastrointestinal stromal tumors (GISTs) harboring a platelet-derived growth factor receptor alpha (PDGFRA) exon 18 variant, including PDGFRA D842V variants, and National Comprehensive Cancer Network guideline recommendations as an option for patients with GIST after third-line treatment, it is important to estimate the potential financial implications of avapritinib on a payer's budget. Objective: To estimate the budget impact associated with the introduction of avapritinib to a formulary for metastatic or unresectable GISTs in patients with a PDGFRA exon 18 variant or after 3 or more previous treatments from the perspective of a US health plan. Design, Setting, and Participants: For this economic evaluation, a 3-year budget impact model was developed in March 2020, incorporating costs for drug acquisition, testing, monitoring, adverse events, and postprogression treatment. The model assumed that avapritinib introduction would be associated with increased PDGFRA testing rates from the current 49% to 69%. The health plan population was assumed to be mixed 69% commercial, 22% Medicare, and 9% Medicaid. Base case assumptions included a GIST incidence rate of 9.6 diagnoses per million people, a metastatic PDGFRA exon 18 mutation rate of 1.9%, and progression rate from first-line to fourth-line treatment of 17%. Exposures: The model compared scenarios with and without avapritinib in a formulary. Main Outcomes and Measures: Annual, total, and per member per month (PMPM) budget impact. Results: In a hypothetical 1-million member plan, fewer than 0.1 new patients with a PDGFRA exon 18 variant per year and 1.2 patients receiving fourth-line therapy per year were eligible for treatment. With avapritinib available, the total increase in costs in year 3 for all eligible adult patients with a PDGFRA exon 18 variant was $46 875, or $0.004 PMPM. For patients undergoing fourth-line treatment, the total increase in costs in year 3 was $69 182, or $0.006 PMPM. The combined total budget impact in year 3 was $115 604, or $0.010 PMPM, including an offset of $3607 in postprogression costs avoided or delayed. The higher rates of molecular testing resulted in a minimal incremental testing cost of $453 in year 3. Conclusions and Relevance: These results suggest that adoption of avapritinib as a treatment option would have a minimal budget impact to a hypothetical US health plan. This would be primarily attributable to the small eligible patient population and cost offsets from reduced or delayed postprogression costs.

Budget impact of everolimus for the treatment of progressive, well-differentiated, non-functional neuroendocrine tumors of gastrointestinal or lung origin that are advanced or metastatic.

BACKGROUND: Advanced neuroendocrine tumors (NETs) are a rare malignancy with considerable need for effective therapies. Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) in 2016 for treatment of adults with progressive, well-differentiated, non-functional NETs of gastrointestinal (GI) or lung origin that are unresectable, locally advanced, or metastatic. OBJECTIVE: To assess the 3-year budget impact for a typical US health plan following availability of everolimus for treatment of GI and lung NETs. Methods An economic model was developed that considered two perspectives: an entire health plan and a pharmacy budget. The total budget impact included costs of drug therapies, administration, hospitalizations, physician visits, monitoring, and adverse events (AEs). The pharmacy model only considered drug costs. RESULTS: In a US health plan with 1 million members, the model estimated 66 patients with well-differentiated, non-functional, and advanced or metastatic GI NETs and 20 with lung NETs undergoing treatment each year. Total budget impact in the first through third year after FDA approval ranged from $0.0568-$0.1443 per member per month (PMPM) for GI NETs and from $0.0181-$0.0355 PMPM for lung NETs. The total budget impact was lower than the pharmacy budget impact because it included cost offsets from administration and AE management for everolimus compared with alternative therapies (e.g. chemotherapies). LIMITATIONS: Because GI and lung NETs are rare diseases with limited published data, several assumptions were made that may influence interpretation of results. CONCLUSIONS: The budget impact for everolimus was minimal in this rare disease area with a high unmet need, largely due to low disease prevalence. These results should be considered in the context of significant clinical benefits potentially provided by everolimus, including significantly longer progression-free survival (PFS) for advanced GI and lung NET patients.

Estimating the incremental net health benefit of requirements for cardiovascular risk evaluation for diabetes therapies.

PURPOSE: To evaluate the advantages and disadvantages of pre-approval requirements for safety data to detect cardiovascular (CV) risk contained in the December 2008 U.S. Food and Drug Administration (FDA) guidance for developing type 2 diabetes drugs compared with the February 2008 FDA draft guidance from the perspective of diabetes population health. METHODS: We applied the incremental net health benefit (INHB) framework to quantify the benefits and risks of investigational diabetes drugs using a common survival metric (life-years [LYs]). We constructed a decision analytic model for clinical program development consistent with the requirements of each guidance and simulated diabetes drugs, some of which had elevated CV risk. Assuming constant research budgets, we estimate the impact of increased trial size on drugs investigated. We aggregate treatment benefit and CV risks for each approved drug over a 35-year horizon under each guidance. RESULTS: The quantitative analysis suggests that the December 2008 guidance adversely impacts diabetes population health. INHB was -1.80 million LYs, attributable to delayed access to diabetes therapies (-0 .18 million LYs) and fewer drugs (-1.64 million LYs), but partially offset by reduced CV risk exposure (0.02 million LYs). Results were robust in sensitivity analyses. CONCLUSION: The health outcomes impact of all potential benefits and risks should be evaluated in a common survival measure, including health gain from avoided adverse events, lost health benefits from delayed or for gone efficacious products, and impact of alternative policy approaches. Quantitative analysis of the December 2008 FDA guidance for diabetes therapies indicates that negative impact on patient health will result.

A systematic review of the economic and humanistic burden of illness in irritable bowel syndrome and chronic constipation.

BACKGROUND: Irritable bowel syndrome (IBS) and chronic constipation (CC) are common functional gastrointestinal disorders affecting 14% and 20% of the U.S. population, respectively. Reviews of the evidence on the burden of illness associated with IBS and CC have not been comprehensive in scope and have not provided an assessment of the distribution of health care costs across categories of resource use. OBJECTIVES: To (a) identify studies from any geographic region or country perspective that measure the economic burden of the disease; (b) analyze the direct (medical, drug, and other components) and indirect costs of illness; and (c) assess published evidence of the humanistic burden as measured by quality of life (QOL). METHODS: An electronic literature search was conducted using journal databases, including MEDLINE, The Cochrane Library, EconLit, CINAHL, and Digestive Disease Week meeting abstracts. Specific search terms used were "irritable bowel syndrome" and "chronic constipation." In databases that accommodated Boolean searches, terms related to economic and quality of life outcomes were incorporated. Studies were included if they evaluated patients with an IBS or CC diagnosis and quantitatively measured the economic or humanistic burden of disease. Results were descriptively analyzed. RESULTS: The search identified a total of 882 unique publications. Thirty-five articles and abstracts met the inclusion criteria. Studies included 1,706 IBS-C, 2,264 IBS-D, 2,892 IBS-A, 15,830 IBS unclassified, and 1,278 CC patients. Nineteen of 35 studies assessed cost-of-illness endpoints, and from the U.S. perspective, the direct cost per-patient for IBS ranged from $1,562 to $7,547 per year, while direct costs of CC ranged from $1,912 to $7,522 per year. From the U.S. perspective, the indirect costs of IBS ranged from $791 to $7,737 per year, and no study assessed the indirect costs of CC. For IBS, data on the distribution of costs attributable to categories of resource use varied widely, particularly outpatient costs (12.7% to > 50% of total costs), inpatient costs (6.2% to 40.8%), and pharmacy or drug costs (5.9% to 46.6%). Comparable data on CC were not identified. Nineteen studies of IBS patients measured the humanistic burden of disease; 14 studies utilized SF-36; and within-study domain scores were significantly lower in IBS patients compared with non-IBS controls. Only 1 study of CC patients reported humanistic burden of disease. CONCLUSIONS: The studies identified in the systematic review varied in the method used to identify patients with IBS and CC. Results were not typically reported by IBS subtype. We observed a large variation in attributable direct and indirect costs and drivers of these costs. Future research should refine burden of illness estimates to subtypes so that estimates associated with IBS-C and CC are differentiated.

Comorbidities in patients with irritable bowel syndrome with constipation or chronic idiopathic constipation: a review of the literature from the past decade.

BACKGROUND: Irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) are common functional bowel disorders. Patients with IBS-C or CIC often present with ≥ 1 comorbidity that coincides with either of these conditions. These comorbidities may make underappreciated contributions to the patient's overall disease burden. OBJECTIVE: To identify the comorbidities that are the most frequently reported in patients with IBS-C or CIC in the medical literature. METHODS: A literature search (January 2001-March 2012) was performed using the Medline and Medline In-Process databases. Studies of adult patients with IBS-C or CIC were selected, and the prevalence rates of the comorbidities were extracted and analyzed according to the body system affected. RESULTS: A total of 70 distinct comorbidities were identified from 35 published studies. These comorbidities involved several body systems, including the gastrointestinal, genitourinary, psychiatric, endocrine, and allergic or immunologic systems. Functional dyspepsia and depression were the most common comorbidities in patients with IBS-C, whereas functional dyspepsia, diabetes, and depression were the most common comorbidities in patients with CIC. CONCLUSION: Patients with IBS-C or CIC frequently experience a wide range of comorbidities that contribute to their disease burden. Thus, we believe that medical professionals should consider common comorbidities when diagnosing and treating patients with IBS-C or CIC.