Over 200 publications, including the composite endpoints regulators now recognize. We publish our methodology in the open so reviewers meet it before your submission does.
Alzheimer's Association International Conference (AAIC) · 2024:Poster Tue-17 · Hendrix, Dickson et al.
Companies recently identified clinical study sites engaging in fraudulent practices, reducing success in Alzheimer's disease (AD) clinical trials. Successful trials are reliable…
When the sample size a conventional design demands is larger than the trial you can run, a Global Statistical Test lets the clinical-endpoint hypotheses be tested anyway. The paper sets out when GST applies, how it is pre-specified, and how it has been received in review.
8 publications
Sorted newest first
2025 · Alzheimer's & Dementia
Duncan, Garrett · Dickson, Samuel · Johnson, Sam · Dayley, Caleb · Hendrix, Suzanne · Mallinckrodt, Craig
INTRODUCTION: The importance of biomarkers as a primary outcome or as supportive evidence of clinical effect is rising as the field shifts toward disease-modifying treatments and earlier intervention, because they have lower variability and can indicate disease progression earlier than clinical outcomes. This study assessed the performance of plasma pTau 181 and 217 as a predictive biomarker and potential primary endpoint in early-phase Alzheimer’s disease (AD) trials. METHODS: Summary data from recent monoclonal antibody (mAb) trials including plasma pTau 181 and 217 were analyzed to evaluate associations between plasma pTau 181/217 and clinical outcomes. The suitability of plasma pTau 181/217 as a surrogate endpoint for internal decision making was assessed using Prentice criteria. Simulations were conducted to explore the statistical power of using plasma pTau 181/217 as a primary outcome in dose-escalation, proof-of-concept (POC) trial designs. Additional criteria for biomarker validation were applied to simulated data. RESULTS: A strong group-level correlation (r = 0.781) was observed between treatment effects on plasma pTau 181/217 and Clinical Dementia Rating scale – Sum of Boxes (CDR-SB). Mean change in plasma pTau 181/217 significantly predicted mean change in CDR-SB (p = 0.013). The treatment effect on pTau 181/217 was ∼2.6 times greater than on CDR-SB. Prentice Criteria 1, 2, and 4 were met or reasonably met; Criterion 3 is not applicable in the POC setting. CONCLUSION: Plasma pTau 181/217 at 6 months shows future promise to reasonably likely predict clinical benefit for drugs that reduce pTau 181/217 levels, supporting its use as a primary endpoint in early-phase trials. With effect sizes similar to those seen with donanemab, adequately powered trials may require as few as 100 participants. Such trials should include prespecified analyses to evaluate individual-level Prentice criteria, and pTau 181/217 results can be used to predict potential Phase 3 clinical outcomes.
2025 · J Prev Alzheimers Dis
Donanemab (Kisunla®), an IgG1 monoclonal antibody targeting N-terminal pyroglutamate-modified forms of amyloid-β, is approved in the United States for treatment of early symptomatic Alzheimer's disease (AD). Appropriate Use Recommendations (AUR) were developed to guide the implementation of donanemab in real-world practice, prioritizing safety considerations and opportunity for effectiveness. The AUR were developed by the AD and Related Disorders Therapeutic Workgroup by consensus, integrating available data and expert opinion. Appropriate candidates for donanemab treatment include persons with mild cognitive impairment or mild dementia due to AD (Clinical Stages 3-4, MMSE 20-30) who have biomarker confirmation of AD pathology by PET or CSF. Tau PET is not required for eligibility. Apolipoprotein E (APOE) genotyping should be performed prior to treatment to inform an individual's risk of developing Amyloid-Related Imaging Abnormalities (ARIA). Pre-treatment MRI should be obtained no more than 12 months prior to treatment. Patients with findings of >4 cerebral microbleeds, cortical superficial siderosis or a major vascular contribution to cognitive impairment should be excluded from treatment. The decision to initiate therapy should be grounded in a shared decision-making process that emphasizes the patient's values and goals of care. Donanemab is administered as a monthly intravenous infusion. Surveillance MRIs to evaluate for ARIA should be performed prior to the 2nd, 3rd, 4th and 7th infusions, prior to the 12th dose in higher risk individuals, and at any time ARIA is suspected clinically. Clinicians may consider discontinuing treatment if amyloid clearance is demonstrated by amyloid PET, typically obtained 12-18 months after initiating treatment.
2025 · J Prev Alzheimers Dis
There is growing consensus in the Alzheimer's community that combination therapy will be needed to maximize therapeutic benefits through the course of the disease. However, combination therapy raises complex questions and decisions for study sponsors, from preclinical research through clinical trial design to regulatory, statistical, and operational considerations. In January 2024, the Alzheimer's Drug Discovery Foundation convened an expert advisory board to discuss the key considerations in each of these areas. Experts agreed on the need to prioritize a combination therapy approach that encompasses a wide range of targets associated with aging and the underlying biology of Alzheimer's disease. Progress in combination therapy could be accelerated by leveraging preclinical research and Phase 1 and 2A trials to identify the most promising combinations for further development, exploring repurposed agents with available preclinical and clinical data, building collaborations across sectors to support operational challenges, and planning for the likely impact of anti-amyloid beta-protein monoclonal antibody therapies on future clinical trial designs.
2024 · Med
Clinical management and therapeutics development for Alzheimer's disease (AD) have entered a new era, with recent approvals of monoclonal antibody therapies targeting the underlying pathophysiology of the disease and modifying its trajectory. Imaging and fluid biomarkers are becoming increasingly important in the clinical development of AD therapeutics. This review focuses on the evidence of fluid biomarkers from recent amyloid-β-targeting clinical trials, summarizing biomarker data across 12 trials. It further proposes a simple framework to put biomarker guidance in the context of amyloid-pathway-targeted disease modification, delineates factors that impact biomarker data in clinical trials, and highlights knowledge gaps and future directions. Increased knowledge and data on biomarkers in the context of disease progression and disease modification will help to better design future AD trials and guide the clinical management of patients on AD-modifying therapies, bringing us closer to the implementation of precision medicine in AD.
2023 · EBioMedicine
Dickson, Samuel · Hendrix, Suzanne
Background: Anti-amyloid vaccines may offer a convenient, affordable, and accessible means of preventing and treating Alzheimer's disease. UB-311 is an anti-amyloid-β active immunotherapeutic vaccine shown to be well-tolerated and to have a durable antibody response in a phase 1 trial. This phase 2a study assessed the safety, immunogenicity, and preliminary efficacy of UB-311 in participants with mild Alzheimer's disease. Methods: A 78-week, randomised, double-blind, placebo-controlled, parallel-group, multicentre, phase 2a study was conducted in Taiwan. Participants were randomised in a 1:1:1 ratio to receive seven intramuscular injections of UB-311 (Q3M arm), or five doses of U311 with two doses of placebo (Q6M arm), or seven doses of placebo (placebo arm). The primary endpoints were safety, tolerability, and immunogenicity of UB-311. Safety was assessed in all participants who received at least one dose of investigational product. This study was registered at ClinicalTrials.gov (NCT02551809). Findings: Between 7 December 2015 and 28 August 2018, 43 participants were randomised. UB-311 was safe, well-tolerated, and generated a robust immune response. The three treatment-emergent adverse events (TEAEs) with the highest incidence were injection-site pain (14 TEAEs in seven [16%] participants), amyloid-related imaging abnormality with microhaemorrhages and haemosiderin deposits (12 TEAEs in six [14%] participants), and diarrhoea (five TEAEs in five [12%] participants). A 97% antibody response rate was observed and maintained at 93% by the end of the study across both UB-311 arms. Interpretation: These results support the continued development of UB-311.
2018 · Alzheimer's & Dementia: Translational Research & Clinical Interventions
Introduction: Autosomal-dominant Alzheimer's disease (ADAD) represents a crucial population for identifying prevention strategies that might modify disease course for cognitively unimpaired individuals at high imminent risk for developing symptoms due to Alzheimer's disease (AD), that is, who have “preclinical” AD. Crenezumab is an antiamyloid monoclonal antibody that binds monomeric and aggregated forms of amyloid β, with highest affinity for oligomers; it is in development for early stages of sporadic AD and for ADAD. Methods: This is a prospective, randomized, double-blind, placebo-controlled phase 2 study of the efficacy of crenezumab versus placebo in asymptomatic PSEN1 E280A mutation carriers from family kindreds with ADAD in Colombia. Participants were randomized to receive either crenezumab or placebo for 260 weeks. The study was designed to enroll a planned total of 300 participants, including 200 preclinical mutation carriers (approximately 100 treatment, 100 placebo) and an additional control group of mutation noncarriers from the same family kindreds included to mask mutation carrier status (100 placebo only). The primary outcome is change in the Alzheimer's Prevention Initiative ADAD Composite Cognitive Test Score from baseline to week 260. Secondary outcomes include time to progression to mild cognitive impairment due to AD or dementia due to AD; changes in dementia severity, memory, and overall neurocognitive functioning; and changes in amyloid–positron emission tomography, fluorodeoxyglucose–positron emission tomography, magnetic resonance imaging volumes, and cerebrospinal fluid levels of β amyloid, tau, and p-tau. Safety and tolerability are assessed. Results: Two hundred fifty-two participants were enrolled between December 2013 and February 2017. Discussion: We describe the first large-scale, potentially label-enabling clinical trial of a preclinical treatment for ADAD. Results from this trial will inform on the efficacy of crenezumab for delaying onset of, slowing decline in, or preventing cognitive impairment in individuals with preclinical ADAD and will foster an improved understanding of AD biomarkers and their relationship to clinical outcomes.
2014 · PLoS One
Identifying safe and effective adjuvants is critical for the advanced development of protein-based vaccines. Pattern recognition receptor (PRR) agonists are increasingly being explored as potential adjuvants, but there is concern that the efficacy of these molecules may be dependent on potentially dangerous levels of non-specific immune activation. The filovirus virus-like particle (VLP) vaccine protects mice, guinea pigs, and nonhuman primates from viral challenge. In this study, we explored the impact of a stabilized dsRNA mimic, polyICLC, on VLP vaccination of C57BL/6 mice and Hartley guinea pigs. We show that at dose levels as low as 100 ng, the adjuvant increased the efficacy of the vaccine in mice. Antigen-specific, polyfunctional CD4 and CD8 T cell responses and antibody responses increased significantly upon inclusion of adjuvant. To determine whether the efficacy of polyICLC correlated with systemic immune activation, we examined serum cytokine levels and cellular activation in the draining lymph node. PolyICLC administration was associated with increases in TNFα, IL6, MCP1, MIP1α, KC, and MIP1β levels in the periphery and with the activation of dendritic cells (DCs), NK cells, and B cells. However, this activation resolved within 24 to 72 hours at efficacious adjuvant dose levels. These studies are the first to examine the polyICLC-induced enhancement of antigen-specific immune responses in the context of non-specific immune activation, and they provide a framework from which to consider adjuvant dose levels.
2013 · Alzheimer's & Dementia
An international task force of investigators from academia, industry, nonprofit foundations, and regulatory agencies met in Monte Carlo, Monaco, on October 31, 2012, to review lessons learned from the recent bapineuzumab and solanezumab trials, and to incorporate insights gained from these trials into future clinical studies. Although there is broad consensus that Alzheimer's disease (AD) should be treated during its earliest stages, the concept of secondary prevention has evolved to be described more accurately as treatment of preclinical, presymptomatic, or early AD. There continues to be a strong emphasis on biomarkers and a need for new biomarkers; however, there has also been a realization, based on completed trials, that the most reliable indicator of clinical efficacy across the entire spectrum of disease from asymptomatic to AD dementia is likely a measure of cognition. The task force made many recommendations that should improve the likelihood of success in future trials, including larger phase 2 or combined phase 2/phase 3 studies, clear evidence of target engagement in the central nervous system, evidence of downstream effects on biomarkers before initiating phase 3 studies, consideration of adaptive and targeted trial designs, and use of sensitive measures of cognition as the most robust indicator of treatment benefit.
Loading more publications…
Looking for older work, or a specific methodology paper? Our research team can point you to the right reference.
Ask our team
