Choice of Starting Dose for Biopharmaceuticals in First-in-Human Phase I Cancer Clinical Trials

Toxicologic Pathology Forum: Opinion on Approaches for Reporting Toxic and Adverse Dose Levels in Nonclinical Toxicology Studies Supporting the Development of Anticancer Pharmaceuticals

The advancement of an investigational new drug in humans is a significant developmental milestone. In first-in-human (FIH)-enabling toxicology studies, the highest dose without a test article-related adverse effect (no-observed-adverse-effect-level [NOAEL]) serves as the basis for deriving a safe FIH starting dose. For anticancer pharmaceuticals, the FIH dose may be calculated using the highest non-severely toxic dose (HNSTD) in nonrodent models or the dose severely toxic to 10% (STD10) in rodents. Given the practice of reporting the NOAEL, but the lack of regulatory requirements to do so for anticancer pharmaceuticals, we conducted an informal survey of 20 companies to answer the question "How is our industry reporting toxic/adverse dose levels in FIH-enabling toxicology studies for anticancer indications?" The data indicated 4 reporting approaches, each providing a path to regulatory acceptance. Within the integrated toxicology study report, 45% of respondents report the HNSTD/STD10, 25% report the NOAEL, 20% report both the HNSTD/STD10 and NOAEL, and 10% do not define either, reserving definitions for regulatory submissions. One reporting approach may be preferred over another for reasons including consistency across indications, repurposing pharmaceuticals, regulatory feedback, or simplicity. The reporting approach should be defined in advance of study initiation, and the pathologist should provide context to support the chosen approach.

Practical Considerations in Determining Adversity and the No-Observed-Adverse-Effect-Level (NOAEL) in Nonclinical Safety Studies: Challenges, Perspectives and Case Studies

Determining the adverse nature of findings from nonclinical safety studies often poses a challenge for the key stakeholders responsible for interpreting the results of definitive toxicity studies in support of pharmaceutical product development. Although there are instances in which responses to treatment clearly indicate intolerability or tissue injury associated with dysfunction; in practice, more often there is uncertainty in characterizing an effect of drug treatment as adverse or not. This is due to the inherent variability in responses of biological test systems to toxicological insults, leaving the ultimate analyses of adversity to individual interpretation and subjectivity. This article is a follow-up to the workshop entitled, "Adverse or Not Adverse?: Thinking process behind adversity determination during nonclinical drug development," conducted at the 58th Annual Meeting of the Society of Toxicology, March 2019 in Baltimore, MD. In this paper, we further discuss and incorporate the perspectives of authors representing different roles, such as Study Director, Study Pathologist, Pharmacology/Toxicology Reviewer (U.S. Food and Drug Administration), and Sponsor in the determination and use of adversity. We also present a practical stepwise approach as an aid in this assessment, and further apply these principles to discuss 10 case studies with different therapeutic modalities and unique challenges.

Allometric scaling of therapeutic monoclonal antibodies in preclinical and clinical settings

Constant technological advancement enabled the production of therapeutic monoclonal antibodies (mAbs) and will continue to contribute to their rapid expansion. Compared to small-molecule drugs, mAbs have favorable characteristics, but also more complex pharmacokinetics (PK), e.g., target-mediated nonlinear elimination and recycling by neonatal Fc-receptor. This review briefly discusses mAb biology, similarities and differences in PK processes across species and within human, and provides a detailed overview of allometric scaling approaches for translating mAb PK from preclinical species to human and extrapolating from adults to children. The approaches described here will remain vital in mAb drug development, although more data are needed, for example, from very young patients and mAbs with nonlinear PK, to allow for more confident conclusions and contribute to further growth of this field. Improving mAb PK predictions will facilitate better planning of (pediatric) clinical studies and enable progression toward the ultimate goal of expediting drug development.

How to improve clinical research in a department of radiation oncology

INTRODUCTION

Radiation therapy is a core modality for cancer treatment. Around 40% of cancer cures include the use of radiotherapy, either as a single strategy or combined with other treatments. In the past decade, substantial technical advances and novel insights into radiobiological properties have considerably improved patients' outcomes. This study overviewed the landscape of clinical research at our radiotherapy department.

METHODS

We surveyed our institutional database of clinical trials to collect information for completed or ongoing radiation therapy clinical trials, from 2005 to December 2017 at the Lucien Neuwirth cancer institute.

RESULTS

A total of 31 clinical trials were undertaken during the study period, of which 4 studies (12.9%) were industry-sponsored and 3 studies (9.7%) were launched by our radiotherapy unit. The vast majority of clinical trials (83.9%) were dedicated to unique organ localization, especially urological cancer (prostate or bladder) (42%). We also observed a shift towards more phase II trials during the study period as well as a special focus on elderly population. Over the last decade, the number of included patients increased by a 5.3 fold input, with 135 inclusions before 2011 and 720 inclusions after 2011.

DISCUSSION

This study provided an observational and comprehensive analysis of radiotherapy research. From a monocentric point-of-view, these results reflected the on-going progress of worldwide radiotherapy research. Based on a 13-years' experience, this study aimed at highlighting essential cues to ensure efficient and perennial research.

Fisetin Prolongs Therapy Window of Brain Ischemic Stroke Using Tissue Plasminogen Activator: A Double-Blind Randomized Placebo-Controlled Clinical Trial

Recombinant tissue plasminogen activator (rt-PA) can be utilized to treat ischemic stroke with safety and effectiveness but limited by a narrow therapeutic window. In the present clinical trial among patients with stroke, we sought to evaluate the potential of fisetin to extend the therapeutic window of rt-PA treatment. Patients with stroke were divided based on their onset-to-treatment time (OTT) and then randomly assigned to receive the rt-PA treatment combined with fisetin or placebo. Primary outcome was evaluated using the National Institutes of Health Stroke scale (NIHSS), and secondary outcome was assessed by serum levels of matrix metalloproteinase (MMP) 2, MMP 9, and C-reactive protein (CRP). Fisetin dramatically improved the treatment outcomes of the patients with stroke in the delayed OTT strata, as revealed by lower NIHSS scores. The beneficial effect of fisetin was likely attributable to reduced levels of MMP-2, MMP-9, and CRP in the serum, as evidenced by strong linear correlations between serum levels of such markers with the NIHSS scores in all enrolled patients. Fisetin may possess the potential to supplement traditional rt-PA treatments among patients with stroke, particularly for those with delayed OTT, and thereby extend the otherwise narrow therapeutic window and improve the treatment outcomes.

Response of safety pharmacologists to challenges arising from the rapidly evolving changes in the pharmaceutical industry

This commentary highlights and expands upon the thoughts conveyed in the lecture by Dr. Alan S. Bass, recipient of the 2017 Distinguished Service Award from the Safety Pharmacology Society, given on 27 September 2017 in Berlin, Germany. The lecture discussed the societal, scientific, technological, regulatory and economic events that dramatically impacted the pharmaceutical industry and ultimately led to significant changes in the strategic operations and practices of safety pharmacology. It focused on the emerging challenges and opportunities, and considered the lessons learned from drug failures and the influences of world events, including the financial crisis that ultimately led to a collapse of the world economies from which we are now recovering. Events such as these, which continue to today, challenge the assumptions that form the foundation of our discipline and dramatically affect the way that safety pharmacology is practiced. These include the latest scientific and technological developments contributing to the design and advancement of safe medicines. More broadly, they reflect the philosophical mission of safety pharmacology and the roles and responsibilities served by safety pharmacologists. As the discipline of Safety Pharmacology continues to evolve, develop and mature, the reader is invited to reflect on past experiences as a framework towards a vision of the future of the field.

Strategies for the development of selenium-based anticancer drugs

Many experimental models demonstrated that inorganic and organic selenium (Se) compounds may have an anticancer activity. However, large clinical studies failed to demonstrate that Se supplementations may prevent the outcome of cancers. Moreover, there are few randomized trials in cancer patients and there is not yet any Se compound recognized as anticancer drug. There is still a need to develop new Se compounds with new strategies. For that, it may be necessary to consider that Se compounds may have a dual role, either as anti-oxidant or as pro-oxidant. Experimental studies demonstrated that it is as pro-oxidant that Se compounds have anticancer effects, even though cancer cells have a pro-oxidant status. The oxidative status differs according to the type of cancer, the stage of the disease and to other parameters. We propose to adapt the doses of the Se compounds to markers of the oxidative stress, but also to markers of angiogenesis, which is strongly related with the oxidative status. A dual role of Se on angiogenesis has also been noted, either as pro-angiogenesis or as anti-angiogenesis. The objective for the development of new Se compounds, having a great selectivity on cancer cells, could be to try to normalize these oxidative and angiogenic markers in cancer patients, with an individual adaptation of doses.

Report on the FDA-AACR Immuno-oncology Drug Development Workshop

The FDA-AACR Immuno-oncology Drug Development Workshop was held in Washington, DC, from October 13 to 14, 2016. This interdisciplinary forum included government, industry, and academic leaders in pharmacology and oncology. The aim of the meeting was to discuss methodologies in nonclinical and clinical research, safety monitoring, efficacy endpoints, and statistical evaluation of cancer immunotherapy products. This summary highlights topics and viewpoints raised by the presenters and discussants and should not be viewed as the conclusions or recommendations of the workshop as a whole. Cancer Immunol Res; 5(4); 282-5. ©2017 AACR.

Biomarkers for nonclinical infusion reactions in marketed biotherapeutics and considerations for study design

The observation of an infusion reaction (IR) in a nonclinical study can cause concern among investigators and regulators in the development of biotherapeutics. Biomarkers can be informative to determine whether the reactions are immune-mediated or test-article related and if there is a potential risk to human subjects. IRs encompass a broad range of adverse events with a variety of triggers; the focus of this paper is IRs due to cytokine release syndrome or immune complex formation and the associated biomarkers. Such reactions generally do not preclude clinical development or marketing approval, because it is widely accepted that immune-mediated reactions in nonclinical species are not predictive of human outcomes. Several US approved products (from 2004 to 2016) have documented IRs in nonclinical species. This review article discusses recent examples, the biomarkers evaluated, and implications for study design and conduct.

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Approved biotherapeutics have produced nonclinical infusion reactions (IRs).

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Nonclinical IRs after a first dose are associated with cytokine release.

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Nonclinical IRs after several doses are associated with ADA.

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ADA-mediated IRs may result in immune complex tissue deposition.

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Diagnosing nonclinical IRs requires a weight-of-evidence approach using biomarkers.

Determination of the starting dose in the first-in-human clinical trials with monoclonal antibodies: a systematic review of papers published between 1990 and 2013

A systematic review was performed to evaluate how the maximum recommended starting dose (MRSD) was determined in first-in-human (FIH) studies with monoclonal antibodies (mAbs). Factors associated with the choice of each MRSD determination method were also identified. PubMed was searched for FIH studies with mAbs published in English between January 1, 1990 and December 31, 2013, and the following information was extracted: MRSD determination method, publication year, therapeutic area, antibody type, safety factor, safety assessment results after the first dose, and number of dose escalation steps. Seventy-nine FIH studies with mAbs were identified, 49 of which clearly reported the MRSD determination method. The no observed adverse effects level (NOAEL)-based approach was the most frequently used method, whereas the model-based approach was the least commonly used method (34.7% vs 16.3%). The minimal anticipated biological effect level (MABEL)- or minimum effective dose (MED)-based approach was used more frequently in 2011–2013 than in 1990–2007 (31.6% vs 6.3%, P=0.036), reflecting a slow, but steady acceptance of the European Medicines Agency’s guidance on mitigating risks for FIH clinical trials (2007). The median safety factor was much lower for the MABEL- or MED-based approach than for the other MRSD determination methods (10 vs 32.2–53). The number of dose escalation steps was not significantly different among the different MRSD determination methods. The MABEL-based approach appears to be safer and as efficient as the other MRSD determination methods for achieving the objectives of FIH studies with mAbs faster.