Improving resource utilisation in SLE drug development through innovative trial design.

SLE is a complex autoimmune disease with considerable unmet need. Numerous clinical trials designed to investigate novel therapies are actively enrolling patients straining limited resources and creating inefficiencies that increase enrolment challenges. This has motivated investigators developing novel drugs and treatment strategies to consider innovative trial designs that aim to improve the efficiency of generating evidence; these strategies propose conducting fewer trials, involving smaller numbers of patients, while maintaining scientific rigour in safety and efficacy data collection and analysis. In this review we present the design of two innovative phase IIb studies investigating efavaleukin alfa and rozibafusp alfa for the treatment of SLE which use an adaptive study design. This design was selected as a case study, investigating efavaleukin alfa, in the Food and Drug Administration's Complex Innovative Trial Design Pilot Program. The adaptive design approach includes prospectively planned modifications at predefined interim timepoints. Interim assessments of futility allow for a trial to end early when the investigational therapy is unlikely to provide meaningful treatment benefits to patients, which can release eligible patients to participate in other-potentially more promising-trials, or seek alternative treatments. Response-adaptive randomisation allows randomisation ratios to change based on accumulating data, in favour of the more efficacious dose arm(s), while the study is ongoing. Throughout the trial the placebo arm allocation ratio is maintained constant. These design elements can improve the statistical power in the estimation of treatment effect and increase the amount of safety and efficacy data collected for the optimal dose(s). Furthermore, these trials can provide the required evidence to potentially serve as one of two confirmatory trials needed for regulatory approval. This can reduce the need for multiple phase III trials, the total patient requirements, person-exposure risk, and ultimately the time and cost of investigational drug development programmes.

SOURCE: a phase 3, multicentre, randomized, double-blind, placebo-controlled, parallel group trial to evaluate the efficacy and safety of tezepelumab in reducing oral corticosteroid use in adults with oral corticosteroid dependent asthma.

BACKGROUND: Many patients with severe asthma continue to experience asthma symptoms and exacerbations despite standard-of-care treatment. A substantial proportion of these patients require long-term treatment with oral corticosteroids (OCS), often at high doses, which are associated with considerable multiorgan adverse effects, including metabolic disorders, osteoporosis and adrenal insufficiency. Tezepelumab is a human monoclonal antibody that blocks the activity of the epithelial cytokine thymic stromal lymphopoietin. In the PATHWAY phase 2b study (NCT02054130), tezepelumab significantly reduced exacerbations by up to 71% in adults with severe, uncontrolled asthma. Several ongoing phase 3 trials (SOURCE, NCT03406078; NAVIGATOR, NCT03347279; DESTINATION, NCT03706079) are assessing the efficacy and safety of tezepelumab in patients with severe, uncontrolled asthma. Here, we describe the design and objectives of SOURCE, a phase 3 OCS-sparing study. METHODS: SOURCE is an ongoing phase 3, multicentre, randomized, double-blind, placebo-controlled study to evaluate the effect of tezepelumab 210 mg administered subcutaneously every 4 weeks on OCS dose reduction in adults with OCS-dependent asthma. The study comprises a 2-week screening and enrolment period, followed by an OCS optimization phase of up to 8 weeks and a 48-week treatment period, which consists of a 4-week induction phase, followed by a 36-week OCS reduction phase and an 8-week maintenance phase. The primary objective is to assess the effect of tezepelumab compared with placebo in reducing the prescribed OCS maintenance dose. The key secondary objective is to assess the effect of tezepelumab on asthma exacerbation rates. Other secondary objectives include the proportion of patients with a reduction in OCS dose (100% or 50% reduction or those receiving < 5 mg) and the effect of tezepelumab on lung function and patient-reported outcomes. CONCLUSIONS: SOURCE is evaluating the OCS-sparing potential of tezepelumab in patients with OCS-dependent asthma. SOURCE also aims to demonstrate that treatment with tezepelumab in patients with severe asthma is associated with reductions in exacerbation rates and improvements in lung function, asthma control and health-related quality of life, while reducing OCS dose. TRIAL REGISTRATION: NCT03406078 ( ClinicalTrials.gov ). Registered 23 January 2018. https://clinicaltrials.gov/ct2/show/NCT03406078.

NAVIGATOR: a phase 3 multicentre, randomized, double-blind, placebo-controlled, parallel-group trial to evaluate the efficacy and safety of tezepelumab in adults and adolescents with severe, uncontrolled asthma.

BACKGROUND: Patients with severe, uncontrolled asthma have a significant unmet need for new treatments that have broader effects on airway inflammation, and that provide greater improvements in asthma outcomes than currently approved biologics and standard-of-care therapies. Tezepelumab is a human monoclonal antibody that blocks the activity of the epithelial cytokine thymic stromal lymphopoietin. In the PATHWAY phase 2b study (NCT02054130), tezepelumab significantly reduced exacerbations by up to 71% in adults with severe, uncontrolled asthma, irrespective of baseline disease phenotype. This article reports the design and objectives of the pivotal phase 3 NAVIGATOR study. METHODS: NAVIGATOR (NCT03347279) is an ongoing randomized, double-blind, placebo-controlled trial in adults (18-80 years old) and adolescents (12-17 years old) with severe, uncontrolled asthma, who are receiving treatment with medium- or high-dose inhaled corticosteroids plus at least one additional controller medication with or without oral corticosteroids (N = 1061). The study population includes approximately equal proportions of patients with high (≥ 300 cells/µL) and low (< 300 cells/µL) blood eosinophil counts. The study comprises a 5-6-week screening period, a 52-week treatment period and a 12-week post-treatment follow-up period. All patients will receive their prescribed controller medications without change throughout the study. The primary efficacy endpoint is the annualized asthma exacerbation rate during the 52-week treatment period. Key secondary endpoints include the effect of tezepelumab on lung function, asthma control and health-related quality of life. DISCUSSION: NAVIGATOR is evaluating the effect of tezepelumab in patients with a broad range of severe asthma phenotypes at baseline, including those with low blood eosinophil counts. The target sample size for NAVIGATOR (N = 1060) was achieved, and it is the largest clinical study of tezepelumab in severe, uncontrolled asthma to date. NAVIGATOR aims to further investigate the effect of tezepelumab on exacerbations and build on observations from the phase 2b PATHWAY study, and to demonstrate further the potential of tezepelumab to provide patients with severe, uncontrolled asthma with improvements in lung function, asthma control and health-related quality of life. TRIAL REGISTRATION: NCT03347279 (ClinicalTrials.gov). Registered 20 November 2017.

Pharmacokinetic/pharmacodynamic data extrapolation models for improved pediatric efficacy and toxicity estimation, with application to secondary hyperparathyroidism.

In most drug development settings, the regulatory approval process is accompanied by extensive studies performed to understand the drug's pharmacokinetic (PK) and pharmacodynamic (PD) properties. In this article, we attempt to utilize the rich PK/PD data to inform the borrowing of information from adults during pediatric drug development. In pediatric settings, it is especially crucial that we are parsimonious with the patients recruited for experimentation. We illustrate our approaches in the context of clinical trials of cinacalcet for treating secondary hyperparathyroidism in pediatric and adult patients with chronic kidney disease, where we model both parathyroid hormone (efficacy endpoint) and corrected calcium levels (safety endpoint). We use population PK/PD modeling of the cinacalcet data to quantitatively assess the similarity between adults and children, and use this information in various hierarchical Bayesian adult borrowing rules whose statistical properties can then be evaluated. In particular, we simulate the bias and mean square error performance of our approaches in settings where borrowing is and is not warranted to inform guidelines for the future use of our methods.

Cinacalcet studies in pediatric subjects with secondary hyperparathyroidism receiving dialysis.

BACKGROUND: Secondary hyperparathyroidism (sHPT), a complication of chronic kidney disease (CKD) characterized by persistently elevated parathyroid hormone (PTH), alterations in calcium-phosphorus homeostasis, and vitamin D metabolism, affects 50% of children receiving dialysis. A significant proportion of these children develop CKD-mineral and bone disorder (CKD-MBD), associated with an increased risk of fractures and vascular calcification. The standard of care for sHPT in children includes vitamin D sterols, calcium supplementation, and phosphate binders. Several agents are approved for sHPT treatment in adults undergoing dialysis, including vitamin D analogs and calcimimetics, with limited information on their safety and efficacy in children. The calcimimetic cinacalcet is approved for use in adults with sHPT on dialysis, but is not approved for pediatric use outside Europe. METHODS: This review provides dosing, safety, and efficacy information from Amgen-sponsored cinacalcet pediatric trials and data from non-Amgen sponsored clinical studies. RESULTS: The Amgen cinacalcet pediatric clinical development program consisted of two Phase 3 randomized studies, one Phase 3 single arm extension study, one open-label Phase 2 study, and two open-label Phase 1 studies. Effects of cinacalcet on PTH varied across studies. Overall, 7.4 to 57.1% of subjects who received cinacalcet in an Amgen clinical trial attained PTH levels within recommended target ranges and 22.2 to 70.6% observed a ≥ 30% reduction in PTH. In addition, significant reductions in PTH were demonstrated in all non-Amgen-supported studies. CONCLUSIONS: To help inform the pediatric nephrology community, this manuscript contains the most comprehensive review of cinacalcet usage in pediatric CKD patients to date.

Network meta-regression for ordinal outcomes: Applications in comparing Crohn's disease treatments.

Crohn's disease (CD) is a life-long condition associated with recurrent relapses characterized by abdominal pain, weight loss, anemia, and persistent diarrhea. In the US, there are approximately 780 000 CD patients and 33 000 new cases added each year. In this article, we propose a new network meta-regression approach for modeling ordinal outcomes in order to assess the efficacy of treatments for CD. Specifically, we develop regression models based on aggregate covariates for the underlying cut points of the ordinal outcomes as well as for the variances of the random effects to capture heterogeneity across trials. Our proposed models are particularly useful for indirect comparisons of multiple treatments that have not been compared head-to-head within the network meta-analysis framework. Moreover, we introduce Pearson residuals and construct an invariant test statistic to evaluate goodness-of-fit in the setting of ordinal outcome data. A detailed case study demonstrating the usefulness of the proposed methodology is carried out using aggregate ordinal outcome data from 16 clinical trials for treating CD.

Considerations in testing treatment effects on transient event driven health status changes measured by patient reported outcomes.

Many treatments and drugs are intended to reduce the occurrence of negative events of interest, control the severity of the events, accelerate recovery from the events, or a combination of these effects. While assessing the clinical effect is typically the primary objective of a trial, testing the treatment effect on the health status of patients based on patient reported outcome (PRO) can be a useful component in determining the value of a treatment. Analysis of PROs in this setting, however, face the following challenges: the PRO value immediately after the event occurrence is often not captured, and the effect of the event on health status measured by the PRO is transient as subjects recover over time. Therefore, traditional statistical methods used to assess treatment effects suffer from low power for PROs. In this manuscript, we apply a kernel smoothing technique to estimate before- and after-event PRO values. We also propose new test outcomes based on observed and estimated PRO values and evaluate tests that focus on the tail distributions. We demonstrate that the tail distribution tests using the new outcomes can achieve high power under certain conditions.

Tezepelumab, an anti-thymic stromal lymphopoietin monoclonal antibody, in the treatment of moderate to severe atopic dermatitis: A randomized phase 2a clinical trial.

BACKGROUND: Tezepelumab (AMG 157/MEDI9929), a first-in-class monoclonal antibody, targets thymic stromal lymphopoietin, a cytokine that is implicated in the pathogenesis of atopic dermatitis (AD). OBJECTIVE: We sought to evaluate the efficacy and safety of tezepelumab in adults with moderate to severe AD. METHODS: In this phase 2a study (NCT02525094), 113 patients were randomized 1:1 to subcutaneous tezepelumab 280 mg or placebo every 2 weeks, plus class 3 topical corticosteroids (TCS). The primary endpoint was the week 12 response rate for a ≥50% reduction in the Eczema Area and Severity Index (EASI50). Secondary endpoints including EASI75, Investigator's Global Assessment, SCORAD 50, SCORAD 75, pruritus numeric rating and 5-D itch scales, and exploratory endpoints (including EASI90) were assessed at weeks 12, and 16 (post hoc). RESULTS: A numerically greater percentage of tezepelumab plus TCS-treated patients achieved EASI50 (64.7%) versus placebo plus TCS (48.2%; P = .091). Numerical improvements over placebo were demonstrated for week 12 secondary and exploratory endpoints, with further improvements at week 16. Treatment-emergent adverse events were similar between treatment groups. LIMITATIONS: Greater than expected response rates in placebo-treated patients were possibly attributable to TCS. CONCLUSION: Although not statistically significant, numerical improvements over placebo for all week 12 endpoints were demonstrated, with greater week 16 responses.

Tezepelumab in Adults with Uncontrolled Asthma.

BACKGROUND: In some patients with moderate-to-severe asthma, particularly those with noneosinophilic inflammation, the disease remains uncontrolled. This trial evaluated the efficacy and safety of tezepelumab (AMG 157/MEDI9929), a human monoclonal antibody specific for the epithelial-cell-derived cytokine thymic stromal lymphopoietin (TSLP), in patients whose asthma remained uncontrolled despite treatment with long-acting beta-agonists and medium-to-high doses of inhaled glucocorticoids. METHODS: In this phase 2, randomized, double-blind, placebo-controlled trial, we compared subcutaneous tezepelumab at three dose levels with placebo over a 52-week treatment period. The primary end point was the annualized rate of asthma exacerbations (events per patient-year) at week 52. RESULTS: The use of tezepelumab at a dose of 70 mg every 4 weeks (low dose; 145 patients), 210 mg every 4 weeks (medium dose; 145 patients), or 280 mg every 2 weeks (high dose; 146 patients) resulted in annualized asthma exacerbation rates at week 52 of 0.26, 0.19, and 0.22, respectively, as compared with 0.67 in the placebo group (148 patients). Thus, exacerbation rates in the respective tezepelumab groups were lower by 61%, 71%, and 66% than the rate in the placebo group (P<0.001 for all comparisons). Similar results were observed in patients regardless of blood eosinophil counts at enrollment. The prebronchodilator forced expiratory volume in 1 second at week 52 was higher in all tezepelumab groups than in the placebo group (difference, 0.12 liters with the low dose [P=0.01], 0.11 liters with the medium dose [P=0.02], and 0.15 liters with the high dose [P=0.002]). A total of 2 patients in the medium-dose group, 3 in the high-dose group, and 1 in the placebo group discontinued the trial regimen because of adverse events. CONCLUSIONS: Among patients treated with long-acting beta-agonists and medium-to-high doses of inhaled glucocorticoids, those who received tezepelumab had lower rates of clinically significant asthma exacerbations than those who received placebo, independent of baseline blood eosinophil counts. (Funded by MedImmune [a member of the AstraZeneca Group] and Amgen; PATHWAY ClinicalTrials.gov number, NCT02054130 .).

Retrospective analysis of relative dose intensity in patients with non-Hodgkin lymphoma receiving CHOP-based chemotherapy and pegfilgrastim.

OBJECTIVES: To evaluate primary prophylaxis with pegfilgrastim, a recombinant human granulocyte colony-stimulating factor, on maintaining relative dose intensity (RDI) in patients with non-Hodgkin lymphoma (NHL) receiving cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or CHOP-rituximab (CHOP-R). METHODS: This retrospective analysis pooled data from pegfilgrastim NHL clinical trials. Patients received up to 6 cycles of CHOP/CHOP-R every 2 (Q2W) or 3 (Q3W) weeks. RDI and the patient incidence of dose delay, reduction, discontinuation, and adverse events leading to dose alteration/discontinuation were summarized overall and by age group (below 65, 65 to 75, and above 75 y) and treatment schedule. RDI during treatment exposure and RDI adjusted by the planned 6 cycles of treatment were calculated. The adjusted RDI was also evaluated with multiple regression analysis. RESULTS: Mean RDI during treatment exposure was 93% and 94% in overall patients in the Q2W and Q3W regimens, respectively. Mean adjusted RDI was 88% and 80%, respectively. The incidence of patients with RDI>85% was lower in older patients (65 y and above). In older patients, the incidence of dose reduction and discontinuation were higher regardless of treatment schedule, whereas dose delay was higher in the Q2W regimen. Multiple regression analysis identified age and cancer stage as potential factors associated with RDI. Adverse events leading to dose alteration/discontinuation were spread across hematological and nonhematological toxicities; older patients had a higher incidence of these adverse events. CONCLUSIONS: Pegfilgrastim primary prophylaxis maintained RDI in NHL patients receiving CHOP/CHOP-R during treatment. Adjusted RDI was lower in elderly patients because of early termination of chemotherapy.

Palifermin reduces severe mucositis in definitive chemoradiotherapy of locally advanced head and neck cancer: a randomized, placebo-controlled study.

PURPOSE: Oral mucositis (OM) is a debilitating toxicity of chemoradiotherapy for head and neck cancer (HNC). This randomized, placebo-controlled, double-blind study evaluated the efficacy and safety of palifermin to reduce OM associated with definitive chemoradiotherapy for locally advanced HNC. PATIENTS AND METHODS: Patients receiving conventionally fractionated radiotherapy (2.0 Gy/d, 5 days/wk to 70 Gy) with cisplatin (100 mg/m(2) on days 1, 22, and 43) received palifermin (180 µg/kg) or placebo before starting chemoradiotherapy and then once weekly for 7 weeks. The primary end point was the incidence of severe, observable, and functional OM (WHO grade 3 to 4). RESULTS: The palifermin (n = 94) and placebo (n = 94) arms were well balanced. The incidence of severe OM was significantly lower for palifermin than for placebo (54% v 69%; P = .041). In the palifermin arm, median time to severe OM was delayed (47 v 35 days), median duration of severe OM was shortened (5 v 26 days), and the incidence of xerostomia grade ≥ 2 was lower (67% v 80%), favoring palifermin; however, the differences were not significant after multiplicity adjustment. Opioid analgesic use, average mouth and throat soreness scores, and chemoradiotherapy compliance were not significantly different between treatment arms. Adverse events were similar between arms (98%, palifermin; 93%, placebo). The most common study drug-related adverse events were rash, flushing, and dysgeusia. After median follow-up of 25.8 months, overall survival and progression-free survival were similar between treatment arms. CONCLUSION: Although palifermin reduced severe functional OM, its role in the management of locally advanced HNC during chemoradiotherapy remains to be elucidated.

A randomized, placebo-controlled phase ii study evaluating the reduction of neutropenia and febrile neutropenia in patients with colorectal cancer receiving pegfilgrastim with every-2-week chemotherapy.

BACKGROUND: Adding irinotecan and/or oxaliplatin to every-2-week 5-fluorouracil (5-FU)/leucovorin (LV) prolongs survival in patients with colorectal cancer (CRC) but increases neutropenia frequency. Pegfilgrastim is indicated to decrease infection as manifested by febrile neutropenia (FN) in patients receiving chemotherapy at > 14-day intervals. This randomized, placebo-controlled phase II study examined pegfilgrastim efficacy and safety in patients with CRC receiving every-2-week chemotherapy. PATIENTS AND METHODS: Patients with CRC were randomized 1:1 to pegfilgrastim 6 mg or placebo administered per-cycle on day 4. Randomization was stratified by chemotherapy regimen (patients received every-2-week FOLFOX4 [5-FU/LV/oxaliplatin], FOLFIRI [5-FU/LV/irinotecan], or FOIL [5-FU/LV/oxaliplatin/irinotecan] at physician discretion). The primary endpoint was incidence of grade 3/4 neutropenia. Secondary endpoints included incidence of grade 3/4 FN and adverse events. After 4 cycles of study treatment, progression-free survival (PFS) and overall survival (OS) were followed for

A comparison of different sample matrices for evaluating functional sensitivity, imprecision and dilution linearity of the Abbott ARCHITECT i2000 TSH assay.

Important performance characteristics for any thyroid-stimulating hormone (TSH) assay include low-end sensitivity, precision across a wide dynamic range, and linear specimen dilution. Laboratories often characterize the performance of their TSH assay using many different sample matrices (e.g. native human serum, synthetic buffer, processed human serum, etc.). However, this can lead to possible confusion as the relationships between sample matrix and assay performance are often poorly understood. The purpose of our study was to evaluate the performance of the ARCHITECT i2000 TSH assay using a variety of different sample matrices. Functional sensitivity was found to be essentially equivalent in both hyperthyroid patient sera (0.0035 microIU/ml) and TSH affinity-stripped (0.0038 microIU/ml) sample matrices. Assay imprecision was also independent of sample matrix, with total imprecision < or = 5.3% for both synthetic buffer and serum matrices. Similarly, specimens were found to dilute linearly over a wide range in both serum and synthetic buffer matrices. We conclude that the i2000 TSH assay measures TSH similarly in a variety of sample matrices. This is an important design feature for this immunoassay which provides assurance that analytical performance assessed with matrices other than unprocessed human serum are representative of assay performance seen with patient specimens.