Publications by authors named "Lanju Zhang"

Article Synopsis
  • The CRISPR gene editing therapy exagamglogene autotemcel (exa-cel) was recently FDA-approved for patients with severe sickle cell disease (SCD) due to its 97% efficacy in reducing vaso occlusive crises (VOCs) over a year demonstrated in a phase III trial.
  • A study using Medicaid claims data found that only 7.7% of a cohort of severe SCD patients remained VOC-free over a one-year period in routine clinical care, highlighting a significant difference from the trial results.
  • The findings suggest that if exa-cel's efficacy is replicated outside of clinical trials, it could greatly improve health outcomes and public health for those living with severe SCD.
View Article and Find Full Text PDF

Background: Circulating polymerized mutant Z-alpha-1 antitrypsin (Z-polymer) constitutes a characteristic feature in alpha-1 antitrypsin deficiency (AATD), but there is limited knowledge about its association with adverse clinical outcomes and liver fibrosis. We explored this association using data from a large cohort of adults with AATD.

Methods: A total of 836 (431 PiZZ, 405 PiMZ) adults with AATD and 312 controls (PiMM) from the European Alpha-1 Liver Cohort (2015-2020) were included.

View Article and Find Full Text PDF
Article Synopsis
  • Exagamglogene autotemcel (exa-cel) is a novel cell therapy using CRISPR-Cas9 gene editing to boost fetal hemoglobin production in patients with transfusion-dependent β-thalassemia.
  • In a phase 3 study, 52 patients aged 12 to 35 underwent treatment with exa-cel after myeloablative conditioning, and 91% achieved transfusion independence for at least 12 months.
  • The therapy showed promising results with high mean total and fetal hemoglobin levels, a favorable safety profile, and no serious adverse events like deaths or cancers reported during the follow-up period.
View Article and Find Full Text PDF

Response adaptive randomization (RAR) is appealing from methodological, ethical, and pragmatic perspectives in the sense that subjects are more likely to be randomized to better performing treatment groups based on accumulating data. However, applications of RAR in confirmatory drug clinical trials with multiple active arms are limited largely due to its complexity, and lack of control of randomization ratios to different treatment groups. To address the aforementioned issues, we propose a Response Adaptive Block Randomization (RABR) design allowing arbitrarily prespecified randomization ratios for the control and high-performing groups to meet clinical trial objectives.

View Article and Find Full Text PDF

In a drug development program, the efficacy and safety of multiple doses can be evaluated in patients through a phase 2b dose ranging study. With a demonstrated dose response in the trial, promising doses are identified. Their effectiveness then is further investigated and confirmed in phase 3 studies.

View Article and Find Full Text PDF

Relative potency assays for biological therapeutics require statistical evaluation to demonstrate similarity between the dose-response curves of a reference standard and the test samples. We developed an equivalence testing approach that can be utilized for the complete potency assay life cycle, from early development until commercialization. This approach was based on the use of generic equivalence margins to enable equivalence testing at the beginning of assay development, when the body of assay-specific data is still very limited.

View Article and Find Full Text PDF

Historical data have been used to augment or replace control arms in some rare disease and pediatric clinical trials. With greater availability of historical data and new methodology such as dynamic borrowing, the inclusion of historical data in clinical trials is an increasingly appealing approach for larger disease areas as well, as this can result in increased power and precision and can minimize the burden on patients in clinical trials. However, sponsors must assess whether the potential biases incurred with this approach outweigh the benefits and discuss this trade-off with the regulatory agencies.

View Article and Find Full Text PDF

Nonalcoholic fatty liver disease (NAFLD) amplifies the risk of various liver diseases, ranging from simple steatosis to nonalcoholic steatohepatitis, fibrosis, and cirrhosis, and ultimately hepatocellular carcinoma. Accumulating evidence suggests the involvement of aberrant microRNAs (miRNAs or miRs) in the activation of cellular stress, inflammation, and fibrogenesis in hepatic cells at different stages of NAFLD and liver fibrosis. Here, we explored the potential role of miR-130b-5p in the pathogenesis of NAFLD, including lipid accumulation and insulin resistance, as well as the underlying mechanism.

View Article and Find Full Text PDF

Inconsistent results across regions have been reported in a number of recent large trials. In this research, by reviewing results from studies that showed inconsistent treatment effects, and summarizing lessons learned, we provide some recommendations for minimizing the chance of inconsistency and allowing more accurate interpretation when such signs of heterogeneity arise, for example: keep the number of regions for consistency evaluation at a minimum to avoid observing false inconsistency signals; proactively address in the protocol the differences in culture, medical practices, and other factors that are potentially different across regions; closely monitor the blinded data from early-enrolled patients to more effectively identify and address issues such as imbalance of baseline covariates or inconsistency of primary outcome rates across regions. For treatments of life-threatening conditions, the stakes for accurate interpretation of MRCT results are high; the criteria for decisions warrant careful consideration.

View Article and Find Full Text PDF

Objective: To assess the efficacy and safety of the anti-interleukin-1α/β (anti-IL-1α/β) dual variable domain immunoglobulin lutikizumab (ABT-981) in patients with knee osteoarthritis (OA) and evidence of synovitis.

Methods: Patients (n = 350; 347 analyzed) with Kellgren/Lawrence grade 2-3 knee OA and synovitis (determined by magnetic resonance imaging [MRI] or ultrasound) were randomized to receive placebo or lutikizumab 25, 100, or 200 mg subcutaneously every 2 weeks for 50 weeks. The coprimary end points were change from baseline in Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score at week 16 and change from baseline in MRI-assessed synovitis at week 26.

View Article and Find Full Text PDF

Objective: To assess the longitudinal reliability of the Outcome Measures in Rheumatology (OMERACT) Thumb base Osteoarthritis Magnetic resonance imaging (MRI) Scoring system (TOMS).

Methods: Paired MRI of patients with hand osteoarthritis were scored in 2 exercises (6-mo and 2-yr followup) for synovitis, subchondral bone defects (SBD), osteophytes, cartilage assessment, bone marrow lesions (BML), and subluxation. Interreader reliability of delta scores was assessed.

View Article and Find Full Text PDF

Adaptive sample size designs, including group sequential designs, have been used as alternatives to fixed sample size designs to achieve more robust statistical power and better trial efficiency. This work investigates the efficiency of adaptive sample size designs as compared to group sequential designs. We show that given a group sequential design, a uniformly more efficient adaptive sample size design based on the same maximum sample size and rejection boundary can be constructed.

View Article and Find Full Text PDF

Background: The purpose of this systematic review and meta-analysis of randomized controlled trials (RCTs) was to evaluate whether intravenous steroids would result in reduced acute pain and postoperative nausea and vomiting (PONV) among patients undergoing total knee arthroplasty (TKA).

Methods: Electronic databases, including PubMed, Embase, Web of Science, and the Cochrane Library, were searched to identify articles published from database inception to July 2016. RCTs that compared the effects of intravenous steroids with the effects of placebo among patients undergoing TKA were included in this meta-analysis.

View Article and Find Full Text PDF

Flexible sample size designs, including group sequential and sample size re-estimation designs, have been used as alternatives to fixed sample size designs to achieve more robust statistical power and better trial efficiency. In this work, a new representation of sample size re-estimation design suggested by Cui et al. [5,6] is introduced as an adaptive group sequential design with flexible timing of sample size determination.

View Article and Find Full Text PDF

It is common in multiregional clinical development that data from a global trial and a local trial (in a target country) together will be used to support local filing in the target country. This approach is considered efficient drug development both globally and in the target country. However, it remains a challenge how to combine global trial data and local trial data toward local filing.

View Article and Find Full Text PDF

It is well recognized that sample size determination is challenging because of the uncertainty on the treatment effect size. Several remedies are available in the literature. Group sequential designs start with a sample size based on a conservative (smaller) effect size and allow early stop at interim looks.

View Article and Find Full Text PDF

Objectives: As heat, pain is one of the most common clinical symptoms. Generally, calcitonin (CT) is prescribed as an analgesic agent for the treatment of pain, especially for the pain caused by osteoporosis or primary and metastatic bone tumor. However, the detailed mechanism remains unknown.

View Article and Find Full Text PDF

Clinical trials can be enriched on subpopulations that may be more responsive to treatments to improve the chance of trial success. In 2012 FDA issued a draft guidance to facilitate enrichment design, where it pointed out the uncertainty on the subpopulation classification and on the treatment effect outside of the identified subpopulation. We consider a novel design strategy where the identified subpopulation (biomarker-positive) is augmented by some biomarker-negative patients.

View Article and Find Full Text PDF

A risk- and science-based approach to control the quality in pharmaceutical manufacturing includes a full understanding of how product attributes and process parameters relate to product performance through a proactive approach in formulation and process development. For dry manufacturing, where moisture content is not directly manipulated within the process, the variability in moisture of the incoming raw materials can impact both the processability and drug product quality attributes. A statistical approach is developed using individual raw material historical lots as a basis for the calculation of tolerance intervals for drug product moisture content so that risks associated with excursions in moisture content can be mitigated.

View Article and Find Full Text PDF

One of the most challenging aspects of the pharmaceutical development is the demonstration and estimation of chemical stability. It is imperative that pharmaceutical products be stable for two or more years. Long-term stability studies are required to support such shelf life claim at registration.

View Article and Find Full Text PDF

Administration of biological therapeutics can generate undesirable immune responses that may induce anti-drug antibodies (ADAs). Immunogenicity can negatively affect patients, ranging from mild reactive effect to hypersensitivity reactions or even serious autoimmune diseases. Assessment of immunogenicity is critical as the ADAs can adversely impact the efficacy and safety of the drug products.

View Article and Find Full Text PDF

Background: The Problem formulation, Objectives, Alternatives, Consequences, Trade-offs, Uncertainties, Risk attitude, and Linked decisions (PrOACT-URL) framework and multiple criteria decision analysis (MCDA) have been recommended by the European Medicines Agency for structured benefit-risk assessment of medicinal products undergoing regulatory review.

Objective: The objective of this article was to provide solutions to incorporate the uncertainty from clinical data into the MCDA model when evaluating the overall benefit-risk profiles among different treatment options.

Methods: Two statistical approaches, the δ-method approach and the Monte-Carlo approach, were proposed to construct the confidence interval of the overall benefit-risk score from the MCDA model as well as other probabilistic measures for comparing the benefit-risk profiles between treatment options.

View Article and Find Full Text PDF

Past decades have seen a rapid growth of biopharmaceutical products on the market. The administration of such large molecules can generate antidrug antibodies that can induce unwanted immune reactions in the recipients. Assessment of immunogenicity is required by regulatory agencies in clinical and nonclinical development, and this demands a well-validated assay.

View Article and Find Full Text PDF

The Bliss independence model is widely used to analyze drug combination data when screening for candidate drug combinations. The method compares the observed combination response (Y(O)) with the predicted combination response (Y(P)), which was obtained based on the assumption that there is no effect from drug-drug interactions. Typically, the combination effect is declared synergistic if Y(O) is greater than Y(P).

View Article and Find Full Text PDF

Administration of biopharmaceutical products can generate immune response that may severely impact the safety or efficacy of the products. Immunogenicity evaluation, required by regulatory agencies, relies on well developed and validated assays. Key to such assay development is the determination of a cut point during assay validation.

View Article and Find Full Text PDF