Effectiveness of patisiran after switching from tafamidis for the treatment of hereditary transthyretin-mediated amyloidosis with polyneuropathy.

BACKGROUND AND PURPOSE: Hereditary transthyretin-mediated amyloidosis with polyneuropathy (ATTRv-PN [v for variant]) is a rare, progressive disease associated with multisystemic impairments. This study assessed the real-world outcomes of patients with ATTRv-PN who switched from tafamidis to patisiran, as well as the reasons for the treatment switch. METHODS: This was a retrospective chart review study at a large expert referral center. Data were extracted from medical charts of patients with ATTRv-PN who switched from tafamidis to patisiran on or before 30 August 2019. Data elements included demographic and clinical characteristics, rationale for switch, and disease measures evaluated from tafamidis initiation through the 12-month patisiran treatment period. RESULTS: Among the 24 patients with ATTRv-PN included in the study, 50.0% had a V30M variant, and the mean (SD) age was 67.3 (8.0) years. During tafamidis treatment (mean [SD] = 30.1 [17.5] months) before switching to patisiran, patients worsened across multiple polyneuropathy measures, including walking ability, Neuropathy Impairment Score, and autonomic function. Neuropathic disease progression on tafamidis was the principal reason for switching to patisiran. After 12 months on patisiran (mean [SD] = 11.7 [1.4] months), patients experienced attenuated disease progression or improvement in the aforementioned measures of polyneuropathy. CONCLUSIONS: Switching from tafamidis to patisiran attenuated the rate of functional decline, and most patients experienced stabilization or improvement of at least one polyneuropathy measure within 12 months of patisiran treatment. Timely switch from tafamidis to patisiran can be beneficial to avoid rapid disease progression in patients with ATTRv-PN.

Indirect treatment comparison (ITC) of the efficacy of vutrisiran and tafamidis for hereditary transthyretin-mediated amyloidosis with polyneuropathy.

BACKGROUND: Vutrisiran and tafamidis are approved therapies for treating hereditary transthyretin-mediated (ATTRv/hATTR) amyloidosis with polyneuropathy, a rapidly progressive and fatal disease. To assist healthcare decision-makers, an indirect treatment comparison (ITC) was undertaken to explore the comparative efficacy of vutrisiran and tafamidis. RESEARCH DESIGN AND METHODS: Individual patient data (vutrisiran vs. placebo) and published results (tafamidis vs. placebo) from phase 3 randomized controlled trials were used in a Bucher analysis to assess differences in treatment effects between vutrisiran and tafamidis on: Neuropathy Impairment Score-Lower Limbs (NIS-LL), Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) score, NIS-LL Response, and modified Body Mass Index (mBMI). RESULTS: Greater treatment effects were observed at 18 months with vutrisiran vs. tafamidis for all endpoints, with statistically significant improvements in polyneuropathy (relative mean change in NIS-LL: -5.3 [95% confidence interval (CI): -9.4, -1.2; p = 0.011]), health-related quality of life (HRQOL, relative mean change in Norfolk QOL-DN: -18.3 [95% CI: -28.6, -8.0; p < 0.001]), and nutritional status (relative mean change in mBMI: 63.9 [95% CI: 10.1, 117.7; p = 0.020]). CONCLUSIONS: This analysis suggests vutrisiran has greater efficacy on multiple measures of polyneuropathy impairment and HRQOL compared to tafamidis in patients with ATTRv amyloidosis with polyneuropathy.

Hereditary transthyretin-mediated (ATTRv/hATTR) amyloidosis is a rare genetic disease that runs in families, affecting about 50,000 people worldwide. This condition results in abnormal protein deposits building up, causing damage to multiple nerves (polyneuropathy) and other organs, which can shorten lifespan and have other harmful effects. Polyneuropathy symptoms include weakness, numbness, pain, dizziness, and diarrhea. Over time, everyday activities become more difficult as patients become increasingly disabled and dependent on others. Several treatments have been approved for the polyneuropathy of ATTRv amyloidosis. Many of these work in different ways to impact the disease process. An indirect treatment comparison is a well-established statistical method used by healthcare decision-makers to compare treatments when head-to-head trials are unavailable. Indirect treatment comparisons using a common approach, the Bucher method, yield similar conclusions to head-to-head studies over 90% of the time. This method was used to compare clinical trial data for tafamidis and vutrisiran, two approved treatments for ATTRv amyloidosis with polyneuropathy. The findings show that vutrisiran is more effective than tafamidis at addressing the polyneuropathy of ATTRv amyloidosis as measured by changes to sensory or motor nervous system functioning and nutritional status. Also, vutrisiran showed greater maintenance of health-related quality of life compared to tafamidis. The expected benefits of vutrisiran over tafamidis are large enough to be noticeable and clinically meaningful to a patient or clinician. This highlights the potential advantages of vutrisiran compared to tafamidis with regard to preservation of physical function and quality of life when treating ATTRv amyloidosis with polyneuropathy.

Indirect treatment comparison of the efficacy of patisiran and inotersen for hereditary transthyretin-mediated amyloidosis with polyneuropathy.

INTRODUCTION: Patisiran and inotersen are two therapies approved for the treatment of hereditary transthyretin-mediated (hATTR) amyloidosis with polyneuropathy, a rapidly progressive disease with a substantial clinical burden. This analysis indirectly compares the efficacy of patisiran and inotersen on neuropathy and quality of life (QOL). METHODS: Published results from the NEURO-TTR study of inotersen and individual patient data from the APOLLO study of patisiran were used. Indirect comparisons were conducted for 15-month changes in neuropathy and QOL endpoints: modified Neuropathy Impairment Score +7 (mNIS+7Ionis,), Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QOL-DN) questionnaire, body mass index (BMI), and Polyneuropathy Disability (PND) score. Analyses were conducted under different assumptions about the impact of missing data and to adjust for baseline differences between studies. RESULTS: Patisiran showed significantly greater treatment effects than inotersen for mNIS+7Ionis (mean difference: -12.3 [95% confidence interval: -21.4, -3.3]), Norfolk QOL-DN (-11.3 [-19.8, -2.9]), and BMI (1.0 [0.4, 1.7]). The proportion of patients with improvement or no change from baseline on PND score was higher for patisiran-treated patients (odds ratio: 8.9 [4.6, 17.5]). Results were consistent and robust across analyses and methods. CONCLUSIONS: Patisiran demonstrated greater treatment effects on neuropathy and QOL than inotersen in patients with hATTR amyloidosis with polyneuropathy.

Experience of patisiran with transthyretin stabilizers in patients with hereditary transthyretin-mediated amyloidosis.

Aim: Examine safety and pharmacodynamics of patisiran alone or with concomitant transthyretin stabilizers from the Phase II open-label extension study and safety and efficacy of patisiran in patients with prior transthyretin stabilizer use from the Phase III APOLLO study. Patients & methods:Post hoc analyses in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy. Results: Patisiran safety was consistent regardless of concomitant or prior transthyretin stabilizers. In the Phase II open-label extension (n = 27), transthyretin reduction was similar over 24 months, regardless of concomitant transthyretin stabilizers. In APOLLO (n = 225), patisiran-treated groups showed stabilization or improvements in neurological function (modified Neuropathy Impairment Score +7) and quality of life (Norfolk Quality of Life-Diabetic Neuropathy questionnaire) at 18 months, regardless of prior transthyretin stabilizers. Conclusion: Patients benefit from patisiran regardless of transthyretin stabilizer use.

An indirect treatment comparison of the efficacy of patisiran and tafamidis for the treatment of hereditary transthyretin-mediated amyloidosis with polyneuropathy.

BACKGROUND: Hereditary transthyretin-mediated amyloidosis (hATTR amyloidosis) is a progressive, life-threatening disease. Until recently, tafamidis was the only approved pharmacotherapy. Patisiran significantly improved polyneuropathy and quality of life (QoL) in the phase III APOLLO trial. In the absence of direct comparisons, this analysis aimed to evaluate the comparative efficacy of tafamidis and patisiran in hATTR amyloidosis with polyneuropathy. RESEARCH DESIGN AND METHODS: Randomized controlled trial evidence for tafamidis was identified by systematic literature review. Indirect treatment comparisons were performed using the standard pairwise Bucher method for endpoints used in both APOLLO and the tafamidis Fx-005 trial: change from baseline in Neuropathy Impairment Score-lower limbs (NIS-LL), Norfolk QoL-Diabetic Neuropathy questionnaire (QoL-DN), NIS-LL response, and mBMI vs. placebo. Inter-trial population differences were assessed by sensitivity analysis. RESULTS: The base-case analysis (FAP Stage 1 APOLLO patients vs. intent-to-treat Fx-005 population) suggested patisiran had a greater treatment effect vs. tafamidis for all endpoints, with significant improvements in mean change in NIS-LL (-5.49) and QoL-DN (-13.10) from baseline to Month 18. Similar trends were observed in all sensitivity analyses. CONCLUSIONS: In the absence of direct comparisons, this analysis suggests patisiran has a greater treatment effect than tafamidis in patients with hATTR amyloidosis with polyneuropathy.

Evaluating Prognostic Factors for Liver Transplantation Among United States Patients With Hereditary Transthyretin-Mediated (hATTR) Amyloidosis Using National Registry Data.

INTRODUCTION: Orthotopic liver transplantation has been used as a treatment for hereditary transthyretin-mediated (hATTR) amyloidosis, a rare, progressive, and multisystem disease. RESEARCH QUESTION: The objective is to evaluate survival outcomes post-liver transplantation in patients with hATTR amyloidosis in the United States and assess whether previously published prognostic factors of patient survival in hATTR amyloidosis are generalizable to the US population. DESIGN: This cohort study examined patients with hATTR amyloidosis undergoing liver transplant in the United States (N = 168) between March 2002 and March 2016 using data reported to the Organ Procurement and Transplantation Network (UNOS)/United Network for Organ Sharing (OPTN). RESULTS: A multivariable Cox hazards regression model showed among all factors tested, only modified body mass index (kg/m2 × g/L) at the time of transplant was significantly associated with survival. Higher modified BMI was associated with lower risk of death relative to a reference population (<600) with historically poor post-transplant outcomes. Patients with modified BMI 1000 to <1200 (hazard ratio [HR] = 0.27; 95% confidence interval [CI] = 0.10-0.73), 1200 to <1400 (HR = 0.20; 95% CI = 0.06-0.75), and ≥1400 (HR = 0.15; 95% CI = 0.04-0.61) exhibited improved adjusted 5-year post-transplant survival of 74%, 80%, and 85%, respectively, versus 33% in the reference population. DISCUSSION: The association between a higher modified BMI threshold at the time of transplant and improved post-transplant survival suggests that the previously published patient selection criterion for modified BMI may not be applicable to the US population.

Intermediate Services After Behavioral Health Hospitalization: Effect on Rehospitalization and Emergency Department Visits.

OBJECTIVE: This study examined the effect of intermediate service use on behavioral health inpatient readmissions and subsequent emergency department (ED) visits among Medicaid enrollees. METHODS: Data were from fee-for-service inpatient admissions from the 2008 Medicaid Analytic eXtract files for adults with a primary diagnosis of a mental or substance use disorder. A multivariate survival analysis estimated the association between posthospital services-particularly intermediate services (residential, partial hospital, intensive outpatient, and other rehabilitative services)-and time to readmission or ED visit. A propensity score-matched sample was used to examine the relationship between time to readmission and ED visit in the nondisabled and disabled populations more closely. RESULTS: The sample included 32,037 adults (nondisabled, 27.6%; disabled, 72.4%). Only 2.5% of nondisabled adults and 5.4% of disabled adults used intermediate services within seven days of hospital discharge. In the multivariate analysis, significant associations were found between intermediate service use and readmissions and ED visits in the nondisabled population (hazard ratio [HR]=.71, p=.04, and HR=.68, p<.01, respectively), but not in the disabled population. Significant associations were also found between use of other health care in the seven-day posthospitalization period and decreased time to readmission and ED visits in the nondisabled population and increased time to readmission and ED visits in the disabled population. In the propensity score--matched analysis, use of intermediate services was not significant in either population. CONCLUSIONS: The low use of intermediate services may reflect limited availability as well as Medicaid coverage limits. Research is needed to determine the optimal number and type of intermediate services for this population to minimize the need for additional hospital services.

Patient factors contributing to variation in same-hospital readmission rate.

The Centers for Medicare & Medicaid Services Hospital Readmission Reduction Program and the Centers for Medicare & Medicaid Innovations Bundled Payments for Care Improvement Initiative hold hospitals accountable for readmissions that occur at other hospitals. A few studies have described the extent to which hospital readmissions occur at the original place of treatment (i.e., same-hospital readmissions). This study uses data from 16 states to describe variation in same-hospital readmissions by patient characteristics across multiple conditions. We found that the majority of 30-day readmissions occur at the same hospital, although rates varied considerably by condition. A significant number of hospitals had very low rates of same-hospital readmissions, meaning that the majority of their readmissions went to other hospitals. Future research should examine why some hospitals are able to retain patients for a same-hospital readmission and others are not.