Search

Cell and gene therapies have demonstrated impressive therapeutic efficacy in various human diseases. Nevertheless, cellular immune response directed against these therapeutic agents is an obstacle for achieving long-lasting clinical efficacy. Therefore, it is crucial to develop robust assays to accurately monitor cellular immunogenicity towards these therapies. Enzyme-linked immunospot (ELISpot) assay is one of the primarily used methods for measuring cellular immune response in clinical programs, which requires isolation of the peripheral blood mononuclear cells (PBMCs). The quality of this clinical material is one of the most critical factors that impact the robust assessment of cellular immune responses. The optimal blood sample processing conditions, however, remain poorly understood. In this study, we examined the impact of blood sample processing time on the performance characteristics of ELISpot to measure antigen-specific cellular responses. Blood samples that were processed after overnight delay resulted in a loss of ELISpot signals. We subsequently optimized several parameters of sample processing, and successfully recovered ELISpot signals for the blood samples that are processed within 32 h. Furthermore, several mitigation strategies were employed that would potentially address the impact of granulocyte contamination on detection of antigen-specific cellular responses. Our investigation provides an extension of sample processing window for clinical studies and is significant for resolving the logistical challenge of whole blood sample shipment for timely PBMC preparation in cell/gene therapy clinical studies. [ABSTRACT FROM AUTHOR]

Interest and efforts to use recombinant adeno-associated viruses (AAV) as gene therapy delivery tools to treat disease have grown exponentially. However, gaps in understanding of the pharmacokinetics/pharmacodynamics (PK/PD) and disposition of this modality exist. This position paper comes from the Novel Modalities Working Group (WG), part of the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ). The pan-industry WG effort focuses on the nonclinical PK and clinical pharmacology aspects of AAV gene therapy and related bioanalytical considerations. Traditional PK concepts are generally not applicable to AAV-based therapies due to the inherent complexity of a transgene-carrying viral vector, and the multiple steps and analytes involved in cell transduction and transgene-derived protein expression. Therefore, we explain PK concepts of biodistribution of AAV-based therapies and place key terminologies related to drug exposure and PD in the proper context. Factors affecting biodistribution are presented in detail, and guidelines are provided to design nonclinical studies to enable a stage-gated progression to Phase 1 testing. The nonclinical and clinical utility of transgene DNA, mRNA, and protein analytes are discussed with bioanalytical strategies to measure these analytes. The pros and cons of qPCR vs. ddPCR technologies for DNA/RNA measurement and qualitative vs. quantitative methods for transgene-derived protein are also presented. Last, best practices and recommendations for use of clinical and nonclinical data to project human dose and response are discussed. Together, the manuscript provides a holistic framework to discuss evolving concepts of PK/PD modeling, bioanalytical technologies, and clinical dose selection in gene therapy. [ABSTRACT FROM AUTHOR]

Oligonucleotide therapeutics (ONTs) are a diverse group of short synthetic nucleic acid–based molecules that exploit innovative intracellular molecular strategies to create novel treatments for a variety of medical conditions. ONT molecules (~7–15 kDa) reside between traditional large and small molecules, and there has been debate regarding their immunogenicity risk. To date, 13 ON drugs have been approved, and as the field is relatively new, there are currently no specific regulatory guidelines to indicate how to develop, validate, and interpret the immunogenicity assays of ONTs. Some investigators do not test for immune responses to ONs while others test for antibodies (Abs) to components within the formulation, which may or may not include aspects of characterization such as domain mapping of ONT conjugates. Similar to other biopharmaceuticals, the immunogenic properties of ONTs could be influenced by sequence, route, dosage, target population, co-medications, etc. The current anti-drug antibody (ADA) data for different approved ONTs suggest that their administration poses a low immunogenicity risk without any significant impact on pharmacokinetics (PK), pharmacodynamics (PD), and safety; nevertheless, until the field matures with data from many more ON drugs, it remains prudent to assess immunogenicity. The emphasis of this article is to highlight how current ADA methodologies might be applied to the development of ONTs, discuss factors that may pose immunogenicity risks, and provide the authors' current position on immunogenicity assessment strategies for ONTs. We also discuss assay parameters that may be appropriate for the detection and characterization of ADAs, including the evaluation of neutralizing ADAs, ADA isotyping, Abs to dsDNA, and pre-existing ADA. Immunogenicity risk assessments (IRAs) and early interactions with regulators will inform how to proceed in late stage/pivotal studies. [ABSTRACT FROM AUTHOR]

Background: Teclistamab (JNJ-64007957), a B-cell maturation antigen × CD3 bispecific antibody, displayed potent T-cell–mediated cytotoxicity of multiple myeloma cells in preclinical studies. Objective: A first-in-human, Phase I, dose escalation study (MajesTEC-1) is evaluating teclistamab in patients with relapsed/refractory multiple myeloma. Patients and Methods: To estimate the efficacious therapeutic dosing range of teclistamab, pharmacokinetic (PK) data following the first cycle doses in the low-dose cohorts in the Phase I study were modeled using a 2-compartment model and simulated to predict the doses that would have average and trough serum teclistamab concentrations in the expected therapeutic range (between EC50 and EC90 values from an ex vivo cytotoxicity assay). Results: The doses predicted to have average serum concentrations between the EC50 and EC90 range were validated. In addition, simulations showed that weekly intravenous and subcutaneous doses of 0.70 mg/kg and 0.72 mg/kg, respectively, resulted in mean trough levels comparable to the maximum EC90. The most active doses in the Phase I study were weekly intravenous doses of 0.27 and 0.72 mg/kg and weekly subcutaneous doses of 0.72 and 1.5 mg/kg, with the weekly 1.5 mg/kg subcutaneous doses selected as the recommended Phase II dose (RP2D). With active doses, exposure was maintained above the mean EC90. All patients who responded to the RP2D of teclistamab had exposure above the maximum EC90 in both serum and bone marrow on cycle 3, Day 1 of treatment. Conclusions: Our findings show that PK simulations of early clinical data together with ex vivo cytotoxicity estimates can inform the identification of a bispecific antibody's therapeutic range. Clinical Trial Registration: NCT03145181, date of registration: May 9, 2017. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to evaluate the pharmacokinetics, immunogenicity, safety, and tolerability of guselkumab, a human monoclonal antibody with high affinity and specificity for binding to interleukin-23. Methods: In this first-in-human, phase 1, randomized study, a single intravenous (IV; 0.03-10 mg/kg) or subcutaneous (SC; 10-300 mg) dose of guselkumab was administered to 47 healthy subjects, and a single SC dose (placebo, 10, 30, 100, 300 mg) was administered to 24 patients with moderate-to-severe psoriasis. Results: Mean maximum observed serum concentration and area under the zero-to-infinity serum concentration-time curve of guselkumab increased in an approximately dose-proportional manner over the dose range of 0.03-10 mg/kg following a single IV administration or 10-300 mg following a single SC administration. Mean clearance and volume of distribution ranged from 3.62-6.03 mL/day/kg and 99.38-123.22 mL/kg, respectively. Mean half-life ranged from 12 to 19 days in healthy subjects and patients with psoriasis. Among guselkumab-treated subjects/patients, 1/30 (3.3 %) healthy subjects in the IV group, 0/6 healthy subjects in the SC group, and 1/20 (5.0 %) patients with psoriasis tested positive for antibodies to guselkumab. No clinically significant adverse events were identified in this study. Conclusion: Guselkumab pharmacokinetic profiles were generally comparable between healthy subjects and patients with psoriasis. Guselkumab, administered as an IV infusion or SC injection, was well tolerated in healthy subjects and patients with psoriasis. [ABSTRACT FROM AUTHOR]

Ligand binding assays (LBAs) have been the method of choice for protein analyte measurements for more than four decades. Over the years, LBA methods have improved in sensitivity and achieved larger dynamic ranges by using alternative detection systems and new technologies. As a consequence, the landscape and application of immunoassay platforms has changed dramatically. The introduction of bead-based methods, coupled with single molecule detection standardization and the ability to amplify assay signals, has improved the sensitivity of many immunoassays, in some cases by several logs of magnitude. Three promising immunoassay platforms are described in this article: Single Molecule Counting (SMC™) from Singulex Inc, Single Molecule Arrays (Simoa™) from Quanterix Corporation, and Immuno-PCR (Imperacer®) from Chimera Biotec GmbH. These platforms have the potential to significantly improve immunoassay sensitivity and thereby address the bioanalytical needs and challenges faced during biopharmaceutical drug development. [ABSTRACT FROM AUTHOR]

A cohort study was designed to evaluate the efficiency of gene transfer and whether biological activity from the expressed therapeutic gene resulted after administration of a recombinant adenovirus containing the human wild-type p53 (p53[SUPwt]) gene (rAd-p53 SCH 58500). The cohort study was conducted in five trial subjects with recurrent ovarian cancer. Each trial subject received multiple cycles of rAd-p53 SCH 58500, each cycle comprised of doses of 7.5 × 10[SUP13] particles on each of five consecutive days. Subjects were treated with rAd-p53 SCH 58500 alone during Cycle 1 and in combination with gemcitabine during the subsequent cycles. Both tumor biopsies and peritoneal aspirates were collected and evaluated for gene transfer and evidence of the biological activities of the expressed p53[SUPwt] gene. Using quantitative PCR and RT-PCR, and in situ PCR, gene transfer and expression were documented in tumor biopsies (four of five patients) collected from Cycle 1. Furthermore, upregulation of p21/WAF1, bax and mdm-2, and downregulation of survivin were observed in these same tumor biopsy samples, suggesting that intraperitoneal administration of rAd-p53 SCH 58500 leads to detectable p53 biological activity in target tumor tissue. In addition, gene transfer and its expression were observed in cells obtained from peritoneal aspirates. These fluids were mainly comprised of polymorphonuclear neutrophils, indicating that successful gene transfer can be achieved by multiple cycle intraperitoneal administration of recombinant adenovirus. [ABSTRACT FROM AUTHOR]