Clinical pharmacology considerations in biologics development

New Drug Development Strategy in Japan: Flexibility in Guideline Adherence

Recently, a new type of drug lag, known as "drug loss" has emerged in Japan. It is a condition where the development of a drug approved in other countries has not been initiated in Japan. For 265 new drugs approved in the United States or Europe during 2010-2020, only 31% had commenced development in Japan as of December 31, 2020. A characteristic feature of Japanese guidelines on new drug development is that, in principle, clinical trial data in Japanese participants are required in each study phase. Given key players in new drug development are shifting from large pharmaceutical companies to emerging biopharma companies, primarily based outside Japan, the necessity for Japanese data may contribute to the drug lag. This study aimed to clarify the guideline adherence to new drug applications in Japan. Of the 159 new drugs approved in Japan between April 2019 and March 2024, the clinical data packages for almost all drugs included both pharmacokinetic (PK) data and efficacy and safety data in Japanese participants, irrespective of the study phase or design. We identified three flexible development approaches: the absence of Japanese dose-response data (39.6%), absence of Japanese confirmatory data generated from phase III randomized controlled trials (35.2%), and post-hoc Japanese PK data (43.0%, 34/79). Biologics, orphan drug designation, antineoplastic agents, and same applicant and originator were identified as factors significantly associated with these flexibilities. The results will help foreign companies, including emerging biopharmas, in formulating effective new drug development strategies, potentially alleviating the drug lag in Japan.

Uncovering the interleukin-12 pharmacokinetic desensitization mechanism and its consequences with mathematical modeling

The cytokine interleukin-12 (IL-12) is a potential immunotherapy because of its ability to induce a Th1 immune response. However, success in the clinic has been limited due to a phenomenon called IL-12 desensitization - the trend where repeated exposure to IL-12 leads to reduced IL-12 concentrations (pharmacokinetics) and biological effects (pharmacodynamics). Here, we investigated IL-12 pharmacokinetic desensitization via a modeling approach to (i) validate proposed mechanisms in literature and (ii) develop a mathematical model capable of predicting IL-12 pharmacokinetic desensitization. Two potential causes of IL-12 pharmacokinetic desensitization were identified: increased clearance or reduced bioavailability of IL-12 following repeated doses. Increased IL-12 clearance was previously proposed to occur due to the upregulation of IL-12 receptor on T cells that causes increased receptor-mediated clearance in the serum. However, our model with this mechanism, the accelerated-clearance model, failed to capture trends in clinical trial data. Alternatively, our novel reduced-bioavailability model assumed that upregulation of IL-12 receptor on T cells in the lymphatic system leads to IL-12 sequestration, inhibiting the transport to the blood. This model accurately fits IL-12 pharmacokinetic data from three clinical trials, supporting its biological relevance. Using this model, we analyzed the model parameter space to illustrate that IL-12 desensitization occurs over a robust range of parameter values and to identify the conditions required for desensitization. We next simulated local, continuous IL-12 delivery and identified several methods to mitigate systemic IL-12 exposure. Ultimately, our results provide quantitative validation of our proposed mechanism and allow for accurate prediction of IL-12 pharmacokinetics over repeated doses.

A review of dose escalation for FDA-approved products treating solid tumors and hematological malignancies in first-in-human trials

First-in-human (FIH) dose-escalation trials on oncology should prioritize safety and emphasize efficacy. We reviewed the FIH trials of 67 anti-tumor products approved by the Food and Drug Administration between 2018 and 2023 and found that the "3 + 3" design remains the predominant dose-escalation method (66.2%). The number of patients receiving sub-therapeutic doses is positively correlated with the maximum tolerated dose (MTD) or maximum dose (MD) to starting dose ratio (P = 0.056) and the number of dose levels in trials (P < 0.001). In addition, the proportion of products with a high ratio in antibody drugs is higher than that in small molecules (P < 0.001). The MTD or MD exceeded the label dose by three or more doses in 22.03% of the products. In conclusion, optimizing the starting dose selection method, refining the way of determining doses, and finding alternative indicators to replace toxicity as the endpoints will increase the effectiveness and broaden the beneficiary scope.

Physiologically based pharmacokinetic models for systemic disposition of protein therapeutics in rabbits

Physiologically based pharmacokinetic (PBPK) modelling is an important tool to predict drug disposition in the body. Rabbits play a pivotal role as a highly valued small animal model, particularly in the field of ocular therapeutics, where they serve as a crucial link between preclinical research and clinical applications. In this context, we have developed PBPK models designed specifically for rabbits, with a focus on accurately predicting the pharmacokinetic profiles of protein therapeutics following intravenous administration. Our goal was to comprehend the influence of key physiological factors on systemic disposition of antibodies and their functional derivatives. For the development of the systemic PBPK models, rabbit physiological factors such as gene expression, body weight, neonatal fragment crystallizable receptor (FcRn) binding, target binding, target concentrations, and target turnover rate were meticulously considered. Additionally, key protein parameters, encompassing hydrodynamic radius, binding kinetic constants (KD, koff), internal degradation of the protein-target complex, and renal clearance, were represented in the models. Our final rabbit models demonstrated a robust correlation between predicted and observed serum concentration-time profiles after single intravenous administration in rabbits, covering IgG, Fab, F(ab)2, Fc, and Fc fusion proteins from various publications. These pharmacokinetic simulations offer a promising platform for translating preclinical findings to clinical settings. The presented rabbit intravenous PBPK models lay an important foundation for more specific applications of protein therapeutics in ocular drug development.

Ulgen K. Advances in Physiologically Based Pharmacokinetic (PBPK) Modeling of Nanomaterials

Nanoparticles (NPs) have been widely used to improve the pharmacokinetic properties and tissue distribution of small molecules such as targeting to a specific tissue of interest, enhancing their systemic circulation, and enlarging their therapeutic properties. NPs have unique and complicated in vivo disposition properties compared to small molecule drugs due to their complex multifunctionality. Physiologically based pharmacokinetic (PBPK) modeling has been a powerful tool in the simulation of the absorption, distribution, metabolism, and elimination (ADME) characteristics of the materials, and it can be used in the characterization and prediction of the systemic disposition, toxicity, efficacy, and target exposure of various types of nanoparticles. In this review, recent advances in PBPK model applications related to the nanoparticles with unique properties, and dispositional features in the biological systems, ADME characteristics, the description of transport processes of nanoparticles in the PBPK model, and the challenges in PBPK model development of nanoparticles are delineated and juxtaposed with those encountered in small molecule models. Nanoparticle related, non-nanoparticle-related, and interspecies-scaling methods applied in PBPK modeling are reviewed. In vitro to in vivo extrapolation (IVIVE) methods being a promising computational tool to provide in vivo predictions from the results of in vitro and in silico studies are discussed. Finally, as a recent advancement ML/AI-based approaches and challenges in PBPK modeling in the estimation of ADME parameters and pharmacokinetic (PK) analysis results are introduced.

Binding Promiscuity of Therapeutic Factor VIII

The binding promiscuity of proteins defines their ability to indiscriminately bind multiple unrelated molecules. Binding promiscuity is implicated, at least in part, in the off-target reactivity, nonspecific biodistribution, immunogenicity, and/or short half-life of potentially efficacious protein drugs, thus affecting their clinical use. In this review, we discuss the current evidence for the binding promiscuity of factor VIII (FVIII), a protein used for the treatment of hemophilia A, which displays poor pharmacokinetics, and elevated immunogenicity. We summarize the different canonical and noncanonical interactions that FVIII may establish in the circulation and that could be responsible for its therapeutic liabilities. We also provide information suggesting that the FVIII light chain, and especially its C1 and C2 domains, could play an important role in the binding promiscuity. We believe that the knowledge accumulated over years of FVIII usage could be exploited for the development of strategies to predict protein binding promiscuity and therefore anticipate drug efficacy and toxicity. This would open a mutational space to reduce the binding promiscuity of emerging protein drugs while conserving their therapeutic potency.

Immunological Drug-Drug Interactions Affect the Efficacy and Safety of Immune Checkpoint Inhibitor Therapies

With the rapid expansion in the development and clinical utility of immune checkpoint inhibitors (ICIs) for oncology, the continual evaluation of the safety profile of such agents is imperative. The safety profile of ICIs as monotherapy is dominated by immune-related adverse events, which can be considered as an extension of the mechanism of action of these immunomodulatory drugs. Further to this, an emerging theme is that ICI treatment can significantly impact upon the tolerability of coadministered medications. Numerous reports in literature indicate that ICIs may alter the immunological perception of coadministered drugs, resulting in undesirable reactions to a variety of concomitant medications. These reactions can be severe in manifestation, including hepatotoxicity and Stevens-Johnson Syndrome (SJS)/toxic epidermal necrolysis (TEN), but may also have detrimental impact on malignancy control. To minimize the impact of such drug-drug interactions on patients, it is imperative to identify medications that may cause these reactions, understand the underlying mechanisms, consider the timing and dosing of comedication, and explore alternative medications with comparable efficacies. Improving our understanding of how concomitant medications affect the safety and efficacy of ICIs can allow for potential culprit drugs to be identified/removed/desensitized. This approach will allow the continuation of ICI therapy that may have been discontinued otherwise, thereby improving malignant control and patient and drug development outcomes.

Revisions to the requirement of the Japanese clinical study data for biosimilar developments in Japan

BACKGROUND

The 'Questions and Answers (Q&A)' document regarding Japanese biosimilar guideline elucidated that Japanese participant enrollment in at least one comparative clinical study was required for the marketing authorization application (MAA) of biosimilars in Japan.

RESEARCH DESIGN AND METHODS

To discuss the requirement of Japanese clinical study data for biosimilar development, the trend in comparative clinical studies conducted for approved biosimilars of monoclonal antibodies and fusion proteins was analyzed, and the consistency of the results between the overall population and the Japanese population according to the publicly available information was reviewed.

RESULTS

The number of comparative clinical studies enrolling Japanese participants was 25 cases, and the type and percentage were 13 (52%) and 12 (48%) cases of comparative pharmacokinetic study and comparative efficacy study, respectively. In all comparative clinical studies, consistent results between the overall population and the Japanese population were shown.

CONCLUSIONS

Our study indicated that Japanese participant enrollment in comparative clinical studies may not always be necessary for biosimilar development when certain conditions are satisfied. This has been described in the revised Q&A document published by the Ministry of Health, Labour and Welfare in January 2024.

Comparison of Cyclic and Linear PEG Conjugates

Bioconjugation of polymers to proteins is a method to impart improved stability and pharmacokinetic properties to biologic systems. However, the precise effects of polymer architecture on the resulting bioconjugates are not well understood. Particularly, cyclic polymers are known to possess unique features such as a decreased hydrodynamic radius when compared to their linear counterparts of the same molecular weight, but have not yet been studied. Here, we report the first bioconjugation of a cyclic polymer, poly(ethylene glycol) (PEG), to a model protein, T4 lysozyme, containing a single engineered cysteine residue (V131C). We compare the stability and activity of this conjugate with those of a linear PEG-T4 lysozyme analogue of similar molecular weight. Furthermore, we used molecular dynamics (MD) simulations to determine the behavior of the polymer-protein conjugates in solution. We introduce cyclic polymer-protein conjugates as potential candidates for the improvement of biologic therapeutics.

Macrophages in cardiovascular diseases: molecular mechanisms and therapeutic targets

The immune response holds a pivotal role in cardiovascular disease development. As multifunctional cells of the innate immune system, macrophages play an essential role in initial inflammatory response that occurs following cardiovascular injury, thereby inducing subsequent damage while also facilitating recovery. Meanwhile, the diverse phenotypes and phenotypic alterations of macrophages strongly associate with distinct types and severity of cardiovascular diseases, including coronary heart disease, valvular disease, myocarditis, cardiomyopathy, heart failure, atherosclerosis and aneurysm, which underscores the importance of investigating macrophage regulatory mechanisms within the context of specific diseases. Besides, recent strides in single-cell sequencing technologies have revealed macrophage heterogeneity, cell-cell interactions, and downstream mechanisms of therapeutic targets at a higher resolution, which brings new perspectives into macrophage-mediated mechanisms and potential therapeutic targets in cardiovascular diseases. Remarkably, myocardial fibrosis, a prevalent characteristic in most cardiac diseases, remains a formidable clinical challenge, necessitating a profound investigation into the impact of macrophages on myocardial fibrosis within the context of cardiac diseases. In this review, we systematically summarize the diverse phenotypic and functional plasticity of macrophages in regulatory mechanisms of cardiovascular diseases and unprecedented insights introduced by single-cell sequencing technologies, with a focus on different causes and characteristics of diseases, especially the relationship between inflammation and fibrosis in cardiac diseases (myocardial infarction, pressure overload, myocarditis, dilated cardiomyopathy, diabetic cardiomyopathy and cardiac aging) and the relationship between inflammation and vascular injury in vascular diseases (atherosclerosis and aneurysm). Finally, we also highlight the preclinical/clinical macrophage targeting strategies and translational implications.

Pharmacokinetics and immunogenicity of eftozanermin alfa in subjects with previously-treated solid tumors or hematologic malignancies: results from a phase 1 first-in-human study

PURPOSE

Eftozanermin alfa is a second-generation tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor agonist that enhances death receptor 4/5 clustering on tumor cells to induce apoptosis. We report the pharmacokinetics and immunogenicity of eftozanermin alfa administered intravenously to 153 adults with previously-treated solid tumors or hematologic malignancies from the first-in-human, open-label, dose-escalation and dose-optimization study.

METHODS

Dose escalation evaluated eftozanermin alfa monotherapy 2.5-15 mg/kg on Day 1 or Days 1/8 of a 21-day cycle. Dose optimization evaluated eftozanermin alfa monotherapy or combination therapy with either oral venetoclax 400-800 mg daily (eftozanermin alfa 1.25-7.5 mg/kg Days 1/8/15 of a 21-day cycle) or chemotherapy (eftozanermin alfa 3.75 or 7.5 mg/kg Days 1/8/15/22 of a 28-day cycle and FOLFIRI regimen [leucovorin, 5-fluorouracil, and irinotecan] with/without bevacizumab on Days 1/15 of a 28-day cycle).

RESULTS

Systemic exposures (maximum observed concentration [Cmax] and area under the concentration-time curve [AUC]) of eftozanermin alfa were approximately dose-proportional across the entire dose escalation range with minimal to no accumulation in Cycle 3 versus Cycle 1 exposures. Comparable exposures and harmonic mean half-lives (35.1 h [solid tumors], 31.3 h [hematologic malignancies]) were observed between malignancy types. Exposures (dose-normalized Cmax and AUC) in Japanese subjects were similar to non-Japanese subjects. Furthermore, eftozanermin alfa/venetoclax combination therapy did not have an impact on the exposures of either agent. Treatment-emergent anti-drug antibodies were observed in 9.4% (13/138) of subjects.

CONCLUSIONS

The study results, including a pharmacokinetic profile consistent with weekly dosing and low incidence of immunogenicity, support further investigation of eftozanermin alfa.

TRIAL REGISTRATION ID

NCT03082209.

Human Dose and Pharmacokinetic Predictions for Biologics at Boehringer Ingelheim: A Retrospective Analysis

INTRODUCTION

Accurate predictions of pharmacokinetics and efficacious doses for biologics in humans are critical for selecting appropriate first-in-human starting doses and dose ranges and for estimating clinical material needs and cost of goods. This also impacts clinical feasibility, particularly for subcutaneously administered biologics.

METHODS

We performed a comprehensive comparison between predicted and observed clearances and doses in humans for a set of 22 biologic drugs developed at Boehringer Ingelheim (BI) over the last 2 decades. The analysis included biologics across three therapeutic areas comprising a wide variety of modalities: mono- and bispecific monoclonal antibodies (mAbs) and nanobodies and a Fab fragment.

RESULTS

Our analysis showed that observed clearances in humans were within twofold of predicted clearances for 17 out of 20 biologics (85%). Six biologics had uncharacteristically high observed human clearances (range 32-280 mL/h) for their respective molecular classes, impacting their clinical developability. For three molecules, molecular characteristics contributed to the high clearance. Clinically selected doses were within twofold of predicted for 58% of projects. With 42% and 25% of projects selecting clinical doses higher than two- or threefold the predicted value, respectively, the importance of better understanding not only the pharmacokinetic (PK) but also the predictivity of pharmacodynamic models is highlighted.

CONCLUSIONS

We provide a clinical pharmacology perspective on the commonly accepted twofold range of human clearance predictions as well as the implications of higher than predicted targeted efficacious plasma concentration on clinical development. Finally, an analysis of key success factors for biologics at BI was conducted, which may be relevant for the entire pharmaceutical industry. This is one of the largest retrospective analyses for biologics and provides further evidence that successful predictions of human PK and efficacious dose will be further facilitated by gathering key translational data early in research.

Drug Design for Alzheimer's Disease: Biologics vs. Small Molecules

There shall probably be no "magic bullet" for Alzheimer's; rather, we should be pursuing a "magic shotgun blast" that will target multiple complementary therapeutic receptors. Although protein misfolding/oligomerization will probably be one of these targets, this alone is insufficient and will require the co-administration of other therapeutic entities engaging targets, such as immunopathy, gliopathy, mitochondriopathy, synaptotoxicity or others. Although polypharmacy is emerging as the preferred therapeutic route, many questions remain unanswered. Should this be a cocktail of biologics, a concoction of small molecules, or a judicious combination of both? Biologics and small molecule drugs display both strengths and weaknesses. When addressing a disease as complex and globally important as Alzheimer's, there should be room for the continuing development of both of these therapeutic classes. Each has much to offer, and when used with their advantages and disadvantages in clear focus, an ultimate solution will probably require contributions from both.

Transportation of mAb Dosing Solution in Intravenous Bag: Impact of Manual, Vehicle, and Pneumatic Tube System Transportation Methods on Product Quality

Monoclonal antibody (mAb) products for intravenous (IV) administration generally require aseptic compounding with a commercial diluent within a pharmacy. The prepared dosing solution in the IV bag may be transported to the dosing location via manual, vehicular, pneumatic tube system (PTS), or a combination of these methods. In this study, the type and level of physical stresses associated with these three methods and their product quality impact for relatively sensitive and stable mAbs were assessed. Vibration was found to be the main stress associated with manual and vehicle transportation methods, although this was at a relatively low level (<1 GRMS/Root-Mean-Square Acceleration). Shock and drop events, at relatively low levels, were also observed with these methods. PTS transportation showed substantially more intense shock, vibration, and drop stresses and the measured levels were up to 91 G/force of acceleration or deceleration, 3.7 GRMS and 39 G, respectively. Using a foam padding insert for PTS transportation reduced the shock level considerably (91 G to 59 G). Transportation of mAb dosing solutions in IV bags via different methods including PTS transportation variables caused a small increase in the subvisible particle counts and there was no change in submicrometer particle distribution. No visible particles and no significant change to soluble aggregate levels were observed after transportation. Strategies such as removal of IV bag headspace prior to transport and in-line filtration poststress reduced the subvisible particles counts. All tested transportation conditions showed negligible impact on other product quality attributes tested. Removal of IV bag headspace prior to PTS transport prevented formation of micro air bubbles and foaming compared to the unaltered IV bag. This study shows examples where manual, vehicle, and PTS transport methods did not significantly impact product quality, and provides evidence that mAb products that are appropriately stabilized in the dosing solution (e.g., with a surfactant) can be transported via a PTS.

Biodistribution and function of coupled polymer-DNA origami nanostructures

Spatial control over the distribution of therapeutics is a highly desired feature, which could limit the side effects of many drugs. Here we describe a nanoscale agent, fabricated from a coupled polymer-DNA origami hybrid that exhibits stability in serum and slow diffusion through tissues, in a manner correlating with shape and aspect ratio. Coupling to fragments of polyethylene glycol (PEG) through polyamine electrostatic interactions resulted in marked stability of the agents in-vivo, with > 90% of the agents maintaining structural integrity 5 days following subcutaneous injection. An agent functionalized with aptamers specific for human tumor necrosis factor TNF-alpha, significantly abrogated the inflammatory response in a delayed-type hypersensitivity model in humanized TNF-alpha mice. These findings highlight polymer-DNA hybrid nanostructures as a programmable and pharmacologically viable update to mainstream technologies such as monoclonal antibodies, capable of exerting an additional layer of control across the spatial dimension of drug activity.

A place for biosimilars in the changing multiple sclerosis treatment landscape

BACKGROUND

The treatment paradigm for multiple sclerosis (MS), particularly relapsing-remitting MS, is heavily reliant on biologic disease-modifying therapies (DMTs). However, the current cost of treatment acts as a significant barrier to access for patients. Over the next few years exclusivity periods for key biologic medicines used in MS are likely to end, opening the door for biosimilar medicines to enter the market.

METHODS

In this review, we discuss what biosimilar medicines are, and how the existing experience with biosimilar medicines across multiple therapy areas can inform the assimilation of biosimilar medicines into the MS treatment landscape in Europe and the US.

RESULTS

There is currently a lack of knowledge and awareness around the distinctions and similarities between small molecules, non-biological complex drugs, and biological medicines, as well as the different categories of follow-on successor medicines. These include biosimilar medicines that offer a matching efficacy and safety profile to the reference biologic. Understanding and recognition of the stringency of the approval pathways required for drug categories such as biosimilars are key in building confidence in treatment outcomes. For example, biosimilar medicines are sometimes perceived only as 'copies' of their reference biologic despite undergoing an extensive approval process requiring that no clinically meaningful differences are observed between the biosimilar medicine and the reference medicine. For MS, introduction of biosimilar medicines in the future will enable more people with MS to receive effective treatment, and also expand access to biologic DMTs in MS. Experiences from the use of biosimilars in multiple therapy areas have shown us that this can result in cost-saving benefits for a healthcare system. Introduction of biosimilar medicines in other therapy areas has also demonstrated the importance of appropriate, accurate education and information for their successful integration into clinical practice.

CONCLUSION

In order to realize optimized treatment outcomes in MS in coming years and to find the appropriate place for biosimilar medicines in the changing MS landscape, it is essential that clinicians and people with MS understand the fundamentals of biosimilars, their potential benefits and consistency of treatment provided by a biosimilar medicine, given the matching efficacy and safety profile to its reference medicine. As evidenced in other therapy areas, biosimilar medicines may reduce key barriers to access by providing a cost-effective alternative to the MS treatment arsenal, while providing the same treatment outcomes as reference biologics.

Co-crystallisation and humanisation of an anti-HER2 single-domain antibody as a theranostic tool

Human epidermal growth factor receptor-2 (HER2) is a well-recognised biomarker associated with 25% of breast cancers. In most cases, early detection and/or treatment correlates with an increased chance of survival. This study, has identified and characterised a highly specific anti-HER2 single-domain antibody (sdAb), NM-02, as a potential theranostic tool. Complete structural description by X-ray crystallography has revealed a non-overlapping epitope with current anti-HER2 antibodies. To reduce the immunogenicity risk, NM-02 underwent a humanisation process and retained wild type-like binding properties. To further de-risk the progression towards chemistry, manufacturing and control (CMC) we performed full developability profiling revealing favourable thermal and physical biochemical 'drug-like' properties. Finally, the application of the lead humanised NM-02 candidate (variant K) for HER2-specific imaging purposes was demonstrated using breast cancer HER2+/BT474 xenograft mice.

Impact of Organ Impairment on the Pharmacokinetics of Therapeutic Peptides and Proteins

The kidneys and liver are major organs involved in eliminating small-molecule drugs from the body. Characterization of the effects of renal impairment (RI) and hepatic impairment (HI) on pharmacokinetics (PK) have informed dosing in patients with these organ impairments. However, the knowledge about the impact of organ impairment on therapeutic peptides and proteins is still evolving. In this study, we reviewed how often therapeutic peptides and proteins were assessed for the effect of RI and HI on PK, the findings, and the resulting labeling recommendations. RI effects were reported in labeling for 30 (57%) peptides and 98 (39%) proteins and HI effects for 20 (38%) peptides and 55 (22%) proteins. Dose adjustments were recommended for RI in 11 of the 30 (37%) peptides and 10 of the 98 (10%) proteins and for HI in 7 of the 20 (35%) peptides and 3 of the 55 (5%) proteins. Additional actionable labeling includes risk mitigation strategies; for example, some product labels have recommended avoid use or monitor toxicities in patients with HI. Over time, there is an increasing structural diversity of therapeutic peptides and proteins, including the use of non-natural amino acids and conjugation technologies, which suggests a potential need for reassessing the need to evaluate the effect of RI and HI. Herein, we discuss scientific considerations for weighing the risk of PK alteration due to RI or HI for peptide and protein products. We briefly discuss other organs that may affect the PK of peptides and proteins administered via other delivery routes.

The Blood-Brain Barrier: Implications for Experimental Cancer Therapeutics

The blood-brain barrier is critically important for the treatment of both primary and metastatic cancers of the central nervous system (CNS). Clinical outcomes for patients with primary CNS tumors are poor and have not significantly improved in decades. As treatments for patients with extracranial solid tumors improve, the incidence of CNS metastases is on the rise due to suboptimal CNS exposure of otherwise systemically active agents. Despite state-of-the art surgical care and increasingly precise radiation therapy, clinical progress is limited by the ability to deliver an effective dose of a therapeutic agent to all cancerous cells. Given the tremendous heterogeneity of CNS cancers, both across cancer subtypes and within a single tumor, and the range of diverse therapies under investigation, a nuanced examination of CNS drug exposure is needed. With a shared goal, common vocabulary, and interdisciplinary collaboration, the field is poised for renewed progress in the treatment of CNS cancers.

Mechanisms of Obesity-Induced Changes in Pharmacokinetics of IgG in Rats

PURPOSE

To evaluate how obesity affects the pharmacokinetics of human IgG following subcutaneous (SC) and intravenous (IV) administration to rats and the homeostasis of endogenous rat IgG.

METHODS

Differences in body weight and size, body composition, and serum concentration of endogenous rat IgG in male Zucker obese (ZUC-FA/FA) and control (ZUC-LEAN) rats were measured from the age of 5 weeks up to 30 weeks. At the age of 23-24 weeks animals received a single IV or SC dose of human IgG (1 g/kg of total body weight), and serum pharmacokinetics was followed for 7 weeks. A mechanistic model linking obesity-related changes in pharmacokinetics with animal growth and changes in body composition was developed.

RESULTS

Significant differences were observed in both endogenous and exogenous IgG pharmacokinetics between obese and control groups. The AUC for human IgG was lower in obese groups (57.6% of control after IV and 48.1% after SC dosing), and clearance was 1.75-fold higher in obese animals. The mechanistic population model successfully captured the data and included several major components: endogenous rat IgG homeostasis with age-dependent synthesis rate; competition of human IgG and endogenous rat IgG for FcRn binding and its effect on endogenous rat IgG concentrations following injection of a high dose of human IgG; and the effect of body size and composition (changing over time and dependent on the obesity status) on pharmacokinetic parameters.

CONCLUSIONS

We identified important obesity-induced changes in the pharmacokinetics of IgG. Results can potentially facilitate optimization of the dosing of IgG-based therapeutics in the obese population.

On-Site Therapeutic Drug Monitoring of Paracetamol Analgesic in Non-Invasively Collected Saliva for Personalized Medicine

Paracetamol or acetaminophen is the main non-opioid analgesic recommended for mild pain by the World Health Organization (WHO) analgesic ladder. However, the high levels used of paracetamol are associated with the hepatotoxicity and nephrotoxicity caused by accumulation of toxic metabolites. The sensor is produced on a polyester substrate containing a full electrochemical device with working, auxiliary, and reference electrodes in which, guiding personalized medicine solutions are not reported. Temporal paracetamol profiles in human saliva are performed with the subject taking different amounts of commercial analgesic pills. The variation of saliva paracetamol levels is demonstrated to be interference free from electroactive interfering species and human saliva constituents. In addition, the sensor displays to be useful as a disposable device for the fast detection of paracetamol in untreated raw saliva following pill intake. The maximum concentration (C_max ) and half-life time (t_1/2 ) for paracetamol are 143.27 µm and 110 min. The results demonstrate the potential of a simple strategy with electrochemical devices for noninvasive personalized therapy toward guiding drug interventions through tracking of active substance, detecting, and correcting insufficiency of absorption to meet individual needs avoiding overdoses, side effects, and intoxication.

A Review of the Pharmacokinetic Characteristics of Immune Checkpoint Inhibitors and Their Clinical Impact Factors

Immune checkpoint inhibitors (ICIs) have been shown to be significant in improving the overall survival rate in certain malignancies with poor prognoses. However, only 20-40% of patients achieve long-term benefits, highlighting the relevance of the factors that influence the treatment, which can help clinicians improve their results and guide the development of new immune checkpoint therapies. In this study, the current pharmacokinetic aspects associated with the ICIs and the factors influencing clinical efficacy were characterised, including in terms of drug metabolism, drug clearance, hormonal effects and immunosuppressive effects.

Development of a spermine lipid for transient antibody expression

Transient expression is the only way to quickly obtain a small scale of antibodies for biomedical research and therapeutic evaluation. The agents for transfecting the suspension cells, e.g. PEI or commercial agents, either lack efficiency or excessively expensive. Herein, a novel spermine-based lipid was developed and fabricated into a cationic liposome for antibody expression. This new transfection agent, designated as sperminoliposome, is feasible, cheap, and highly effective to produce antibodies. Compared to PEI, a 3 times higher yield of antibody was obtained by sperminoliposome during the transient expression of cetuximab in suspension 293F cells. Characterizations confirmed that the expressed antibody is fully functional and eligible for further research. Our study provides an effective tool for the rapid production of antibodies economically and feasibly.

Monoclonal antibody and protein therapeutic formulations for subcutaneous delivery: high-concentration, low-volume vs. low-concentration, high-volume

Biologic drugs are used to treat a variety of cancers and chronic diseases. While most of these treatments are administered intravenously by trained healthcare professionals, a noticeable trend has emerged favoring subcutaneous (SC) administration. SC administration of biologics poses several challenges. Biologic drugs often require higher doses for optimal efficacy, surpassing the low volume capacity of traditional SC delivery methods like autoinjectors. Consequently, high concentrations of active ingredients are needed, creating time-consuming formulation obstacles. Alternatives to traditional SC delivery systems are therefore needed to support higher-volume biologic formulations and to reduce development time and other risks associated with high-concentration biologic formulations. Here, we outline key considerations for SC biologic drug formulations and delivery and explore a paradigm shift: the flexibility afforded by low-to-moderate-concentration drugs in high-volume formulations as an alternative to the traditionally difficult approach of high-concentration, low-volume SC formulation delivery.

Fetal and Neonatal Adverse Drug Reactions Associated with Biologics Taken During Pregnancy by Women with Autoimmune Diseases: Insights from an Analysis of the World Health Organization Pharmacovigilance Database (VigiBase®)

INTRODUCTION

Published data on the safety of biologics other than tumor necrosis factor (TNF) inhibitors during pregnancy are limited.

OBJECTIVE

The aim was to detect pharmacovigilance signals for fetal and neonatal adverse drug reactions (ADRs) to biologics taken by pregnant women with autoimmune diseases.

METHODS

We performed a disproportionality analysis of the World Health Organization's VigiBase^® pharmacovigilance database from 1968 to June 1, 2021. Data were collected in June 2021. By using terms for different hierarchical levels of the Medical Dictionary for Regulatory Activities, we selected the following fetal or neonatal ADRs: stillbirth, premature birth, low birth weight, small for gestational age, and congenital malformations. The frequency of all identified ADRs for biologics of interest (adalimumab, infliximab, golimumab, certolizumab, etanercept, anakinra, canakinumab, tocilizumab, sarilumab, ustekinumab, guselkumab, secukinumab, ixekizumab, belimumab, abatacept, and rituximab) was compared with that of all other reports for all other drugs and quoted as the reporting odds ratio (ROR) [95% confidence interval]. Reports with known concomitant use of teratogenic drugs were excluded from the main analysis. Other analyses included ROR stratifications by therapeutic indication in the periods 1968-2021 and 2001-2021, and an analysis after excluding reports with steroids.

RESULTS

In the main analysis, the RORs were particularly high for musculoskeletal malformations with anakinra (7.18 [3.50-14.73]), canakinumab (19.54 [12.82-29.79]), and abatacept (5.09 [2.77-9.33]), and for immune system disorders with canakinumab (347.88 [217.9-555.50]) and rituximab (9.27 [2.95-29.15]). After the exclusion of reports with steroids, the ROR was significant for neonatal infections with belimumab (28.49 [5.75-141.25]).

CONCLUSION

We identified possible associations with some adverse fetal and neonatal outcomes, suggesting that vigilance is required when prescribing certain biologics during pregnancy.

Opportunistic Challenges of Computer-aided Drug Discovery of Lipopeptides: New Insights for Large Molecule Therapeutics

Computer-aided drug designing is a promising approach to defeating the dry pipeline of drug discovery. It aims at reduced experimental efforts with cost-effectiveness. Naturally occurring large molecules with molecular weight higher than 500 Dalton such as cationic peptides, cyclic peptides, glycopeptides and lipopeptides are a few examples of large molecules which have successful applications as the broad spectrum antibacterial, anticancer, antiviral, antifungal and antithrombotic drugs. Utilization of microbial metabolites as potential drug candidates incur cost effectiveness through large scale production of such molecules rather than a synthetic approach. Computational studies on such compounds generate tremendous possibilities to develop novel leads with challenges to handle these complex molecules with available computational tools. The opportunities begin with the desired structural modifications in the parent drug molecule. Virtual modifications followed by molecular interaction studies at the target site through molecular modeling simulations and identification of structure-activity relationship models to develop more prominent and potential drug molecules. Lead optimization studies to develop novel compounds with increased specificity and reduced off targeting is a big challenge computationally for large molecules. Prediction of optimized pharmacokinetic properties facilitates development of a compound with lower toxicity as compared to the natural compounds. Generating the library of compounds and studies for target specificity and ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) for large molecules are laborious and incur huge cost and chemical wastage through in-vitro methods. Hence, computational methods need to be explored to develop novel compounds from natural large molecules with higher specificity. This review article is focusing on possible challenges and opportunities in the pathway of computer-aided drug discovery of large molecule therapeutics.

A Winning New Combination? Toward Clinical Application in Oncology

Immunotherapy has substantial attention in oncology due to the success of CTLA-4 and PD-1 inhibitors in the treatment of melanoma, lung cancer, head and neck cancer, renal cell carcinoma, and Hodgkin's lymphoma. A deeper understanding of interaction of tumor with its environment and the immune system provides best guide for oncology research. Recent studies in oncology have explained how a tumor alters antigen presentation, avoids detection, and activation of the host immune system to live and develop. Understanding the connections between the tumor and the immune system has resulted in several innovative therapy options. The extensive field of gene therapy has provided a number of cutting-edge medicines that are expected to play an important role in lowering cancer-related mortality. This article explains the history, important breakthroughs, and future prospects for three separate gene therapy treatment modalities: immunotherapy, oncolytic virotherapy, and gene transfer. Immunotherapies have completely changed how cancer is treated, especially for individuals whose condition was previously thought to be incurable. Examples include ACT (adoptive cell therapy) and ICB (immune checkpoint blockade). This review article will discuss the relationship between the immune response to cancer and the mechanisms of immunotherapy resistance. It will cover combination drugs authorized by the US Food and Drug Administration and provide a thorough overview of how these drugs are doing clinically right now. Cytokines, vaccines, and other soluble immunoregulatory agents, innate immune modifiers, ACT, virotherapy, and other treatment modalities will all be covered in detail.

Protein and Gene Delivery Systems for Neurodegenerative Disorders: Where Do We Stand Today?

It has been estimated that every year, millions of people are affected by neurodegenerative disorders, which complicate their lives and their caregivers' lives. To date, there has not been an approved pharmacological approach to provide the complete treatment of neurodegenerative disorders. The only available drugs may only relieve the symptoms or slow down the progression of the disease. The absence of any treatment is quite rational given that neurodegeneration occurs by the progressive loss of the function or structure of the nerve cells of the brain or the peripheral nervous system, which eventually leads to their death either by apoptosis or necrotic cell death. According to a recent study, even though adult brain cells are injured, they can revert to an embryonic state, which may help to restore their function. These interesting findings might open a new path for the development of more efficient therapeutic strategies to combat devastating neurodegenerative disorders. Gene and protein therapies have emerged as a rapidly growing field for various disorders, especially neurodegenerative diseases. Despite these promising therapies, the complete treatment of neurodegenerative disorders has not yet been achieved. Therefore, the aim of this review is to address the most up-to-date data for neurodegenerative diseases, but most importantly, to summarize the available delivery systems incorporating proteins, peptides, and genes that can potentially target such diseases and pass into the blood-brain barrier. The authors highlight the advancements, at present, on delivery based on the carrier, i.e., lipid, polymeric, and inorganic, as well as the recent studies on radiopharmaceutical theranostics.

Efficacy of Tildrakizumab Across Different Body Weights in Moderate-to-Severe Psoriasis Over 5 Years: Pooled Analyses from the reSURFACE Pivotal Studies

Introduction

Tildrakizumab (TIL), a monoclonal antibody that selectively targets interleukin-23p19, has been approved for the treatment of moderate-to-severe plaque psoriasis. According to the European Medicines Agency Summary of Product Characteristics, the recommended dose is 100 mg, but a 200 mg dose can be used in patients with certain characteristics, such as a high disease burden or body weight (BW) ≥ 90 kg. Fixed one-dose biological therapies tend to become less effective in patients with high BW. This post-hoc study describes the long-term efficacy of TIL across different BWs in pivotal clinical trials.

Methods

A 5-year pooled analysis of two double-blind, randomised, controlled phase III trials—reSURFACE 1 and 2—was performed. Efficacy measures were the proportions of the patients with an absolute Psoriasis Area and Severity Index (PASI) of < 3 and < 1 and a Dermatology Life Quality Index (DLQI) of 0/1. The study population included patients randomised to TIL 100 mg or TIL 200 mg who received ≥ 1 TIL dose up to week 12 (part 1 of the trial) or up to week 28 (part 2) and patients who were responders (≥ 75% improvement in PASI) to TIL 100 or TIL 200 mg at week 28 and who were maintained on the same dose up to week 244. Efficacy was evaluated by analysing BW subgroups at weeks 28, 52 and 244. Missing data were analysed using multiple imputation. Safety was assessed in the all-patients-as-treated population.

Results

The proportions of TIL-treated patients with PASI < 3 and < 1 (up to week 244) and DLQI 0/1 (up to week 52) were similar for patients with BW < 90 or ≥ 90 kg, regardless of dose. Patients ≥ 120 kg had greater efficacy outcomes at the 200 mg dose. Safety outcomes were similar regardless of treatment dose and weight (< 120/≥ 120 kg).

Conclusion

In patients with BW ≥ 120 kg, TIL 200 mg is more efficacious than TIL 100 mg, with similar favourable safety profiles obtained regardless of dose and BW group.

Trial registration

ClinicalTrials.gov NCT01722331 (reSURFACE 1) and NCT01729754 (reSURFACE 2).

Real-world multicentre observational study including population pharmacokinetic modelling to evaluate the exposure-response relationship of vedolizumab in inflammatory bowel disease: ERELATE Study

BACKGROUND

ERELATE was a phase 4, multinational, retrospective, observational study.

AIM

To evaluate the relationship between intravenous vedolizumab exposure and treatment outcomes over 52 weeks in adults with ulcerative colitis (UC) or Crohn's disease (CD).

METHODS

Real-world data from patients with UC or CD treated with intravenous vedolizumab in nine centres in six countries were collected retrospectively. Treatment outcomes were collected at Weeks 14, 26 and 52. An established population pharmacokinetic model (incorporating observed vedolizumab concentrations based on a Bayesian approach) was used to predict individual vedolizumab exposure. Vedolizumab exposure-response relationship was evaluated overall, by indication and based on baseline characteristics.

RESULTS

The study population (n = 695; UC, n = 304; CD, n = 391) had a median age of 39 years; 47.9% were male and 86.9% had prior tumour necrosis factor antagonist exposure. By Week 14, clinical, endoscopic, deep (clinical plus endoscopic) and biologic remission was achieved by 47.3%, 59.6%, 30.7% and 19.0% of patients respectively. Higher vedolizumab trough concentration early in treatment was consistently associated with clinical remission at later time points. Clinical remission at Week 14 and Week 52 was associated with Week 6 trough concentrations of ≥31.0 and ≥32.0 μg/ml respectively. Importantly, multivariable analysis identified baseline clearance as the only exposure measure predictive of clinical and deep remission at Week 52.

CONCLUSIONS

In this real-world study, a positive exposure-response relationship was observed for vedolizumab. Vedolizumab concentration during induction may be an important predictor of short- and long-term outcomes, and similarly, vedolizumab baseline clearance may be an important predictor of remission.

Mathematical Modeling of Complement Pathway Dynamics for Target Validation and Selection of Drug Modalities for Complement Therapies

Motivation: The complement pathway plays a critical role in innate immune defense against infections. Dysregulation between activation and regulation of the complement pathway is widely known to contribute to several diseases. Nevertheless, very few drugs that target complement proteins have made it to the final regulatory approval because of factors such as high concentrations and dosing requirements for complement proteins and serious side effects from complement inhibition.

Methods: A quantitative systems pharmacology (QSP) model of the complement pathway has been developed to evaluate potential drug targets to inhibit complement activation in autoimmune diseases. The model describes complement activation via the alternative and terminal pathways as well as the dynamics of several regulatory proteins. The QSP model has been used to evaluate the effect of inhibiting complement targets on reducing pathway activation caused by deficiency in factor H and CD59. The model also informed the feasibility of developing small-molecule or large-molecule antibody drugs by predicting the drug dosing and affinity requirements for potential complement targets.

Results: Inhibition of several complement proteins was predicted to lead to a significant reduction in complement activation and cell lysis. The complement proteins that are present in very high concentrations or have high turnover rates (C3, factor B, factor D, and C6) were predicted to be challenging to engage with feasible doses of large-molecule antibody compounds (≤20 mg/kg). Alternatively, complement fragments that have a short half-life (C3b, C3bB, and C3bBb) were predicted to be challenging or infeasible to engage with small-molecule compounds because of high drug affinity requirements (>1 nM) for the inhibition of downstream processes. The drug affinity requirements for disease severity reduction were predicted to differ more than one to two orders of magnitude than affinities needed for the conventional 90% target engagement (TE) for several proteins. Thus, the QSP model analyses indicate the importance for accounting for TE requirements for achieving reduction in disease severity endpoints during the lead optimization stage.

Population Pharmacokinetics of Tanezumab Following Intravenous or Subcutaneous Administration to Patients with Osteoarthritis or Chronic Low Back Pain

AIMS

Describe population pharmacokinetics of intravenous (IV) and subcutaneous (SC) tanezumab across Phase 2b/3 studies of osteoarthritis (OA) and chronic low back pain (CLBP). Methods Data from 10 studies of IV or SC tanezumab (2.5-20 mg every 8 weeks for up to 56 weeks) were included in a multi-step analysis. In Step 1, a two-compartment model with linear and non-linear elimination (based on prior analysis of pre-2015 IV osteoarthritis studies) was expanded to include other pre-2015 studies. In Step 2, post-2015 SC studies were combined into the model. Steps 3 and 4 evaluated impact of baseline nerve growth factor (NGF) and treatment-emergent anti-drug antibodies (TE ADA).

RESULTS

SC bioavailability was estimated at 62-76%. The key disposition parameters CL, V_c , V_p , and KM were estimated to be 0.133 L·day^-1 , 2.6 L, 1.77 L and 31.2 μg·L^-1 . Plasma tanezumab concentration was predicted to reach C_max at 8.9- 11.2 days following single and multiple SC administration in typical patients within the dose range of SC Phase 3 studies (2.5-10 mg every 8 weeks). Exposure of a typical patient was similar between IV and SC for the second part of the dosing interval (weeks 4-8). Covariates selected on the absorption parameters were WT, age, sex, and injection site. Baseline NGF had minimal effect on maximum elimination capacity and TE ADA status was associated with slightly higher tanezumab clearance (6-7%).

CONCLUSION

Our model adequately described plasma tanezumab concentration versus time following IV or SC administration. WT was the most influential covariate with respect to absorption of tanezumab in comparison to patient population (OA and CLBP) or other demographics. There was no clinically relevant effect of baseline NGF or TE ADA on tanezumab PK.

H84T BanLec has broad spectrum antiviral activity against human herpesviruses in cells, skin, and mice

H84T BanLec is a molecularly engineered lectin cloned from bananas with broad-spectrum antiviral activity against several RNA viruses. H84T BanLec dimers bind glycoproteins containing high-mannose N-glycans on the virion envelope, blocking attachment, entry, uncoating, and spread. It was unknown whether H84T BanLec is effective against human herpesviruses varicella-zoster virus (VZV), human cytomegalovirus (HCMV), and herpes simplex virus 1 (HSV-1), which express high-mannose N-linked glycoproteins on their envelopes. We evaluated H84T BanLec against VZV-ORF57-Luc, TB40/E HCMV-fLuc-eGFP, and HSV-1 R8411 in cells, skin organ culture, and mice. The H84T BanLec EC50 was 0.025 µM for VZV (SI50 = 4000) in human foreskin fibroblasts (HFFs), 0.23 µM for HCMV (SI50 = 441) in HFFs, and 0.33 µM for HSV-1 (SI50 = 308) in Vero cells. Human skin was obtained from reduction mammoplasties and prepared for culture. Skin was infected and cultured up to 14 days. H84T BanLec prevented VZV, HCMV and HSV-1 spread in skin at 10 µM in the culture medium, and also exhibited dose-dependent antiviral effects. Additionally, H84T BanLec arrested virus spread when treatment was delayed. Histopathology of HCMV-infected skin showed no overt toxicity when H84T BanLec was present in the media. In athymic nude mice with human skin xenografts (NuSkin mice), H84T BanLec reduced VZV spread when administered subcutaneously prior to intraxenograft virus inoculation. This is the first demonstration of H84T BanLec effectiveness against DNA viruses. H84T BanLec may have additional unexplored activity against other, clinically relevant, glycosylated viruses.

Polymer nano-systems for the encapsulation and delivery of active biomacromolecular therapeutic agents

Biomacromolecular therapeutic agents, particularly proteins, antigens, enzymes, and nucleic acids are emerging as powerful candidates for the treatment of various diseases and the development of the recent vaccine based on mRNA highlights the enormous potential of this class of drugs for future medical applications. However, biomacromolecular therapeutic agents present an enormous delivery challenge compared to traditional small molecules due to both a high molecular weight and a sensitive structure. Hence, the translation of their inherent pharmaceutical capacity into functional therapies is often hindered by the limited performance of conventional delivery vehicles. Polymer drug delivery systems are a modular solution able to address those issues. In this review, we discuss recent developments in the design of polymer delivery systems specifically tailored to the delivery challenges of biomacromolecular therapeutic agents. In the future, only in combination with a multifaceted and highly tunable delivery system, biomacromolecular therapeutic agents will realize their promising potential for the treatment of diseases and for the future of human health.

A Phase 1 first-in-human study of the safety, tolerability, and pharmacokinetics of the ROBO2 fusion protein PF-06730512 in healthy participants

Proteinuria associated with podocyte effacement is a hallmark of focal segmental glomerulosclerosis (FSGS). Preclinical studies implicated ROBO2/SLIT2 signaling in the regulation of podocyte adhesion, and inhibition of this pathway is a novel target to slow FSGS disease progression. This first-in-human dose-escalation study evaluated the safety, tolerability, pharmacokinetics, and immunogenicity of PF-06730512, an Fc fusion protein that targets the ROBO2/SLIT2 pathway, in healthy adults. In this Phase 1, double-blind, sponsor-open study, single ascending dose (SAD) cohorts were randomized to receive up to 1000 mg or placebo intravenously (IV); multiple ascending dose (MAD) cohorts were randomized to receive up to 400 mg subcutaneous (SC) doses, 1000 mg IV dose, or matching placebo. Safety evaluations were performed up to 71 (SAD) and 113 (MAD) days after dosing; blood samples were collected to measure serum PF-06730512 concentrations and antidrug antibodies (ADA) to PF-06730512. Seventy-nine participants (SAD, 47; MAD, 32) were enrolled. There were 108 mild (SAD, 46; MAD, 62) and 21 moderate (SAD, 13; MAD, 8) treatment-emergent adverse events (TEAEs); no deaths, treatment-related serious AEs, severe TEAEs, or infusion reactions were reported. PF-06730512 exposure generally increased in an approximately dose-proportional manner; mean t1/2 ranged from 12-15 days across 50-1000 mg doses. Immunogenicity incidence was low (SAD, 0 ADA+; MAD, 2 ADA+). In conclusion, single IV doses of PF-06730512 up to 1000 mg and multiple IV and SC dosing up to 1000 and 400 mg, respectively, were safe and well tolerated in healthy participants. Further trials in patients with FSGS are warranted. Clinical trial registration: Clinicaltrials.gov: NCT03146065.

Pharmacokinetic Modeling and Predictive Performance: Practical Considerations for Therapeutic Monoclonal Antibodies

Population pharmacokinetic (PopPK) model parameter estimation and predictive performance depend on the data adequacy for model building. PopPK models of therapeutic monoclonal antibodies (mAbs) may not be well supported by commonly used sparse sampling in late-stage development because of the slow absorption (days) and long half-life (weeks) of mAbs, affecting accuracy of predicted exposure metrics which are often used to support drug development. A case study was presented for a representative mAb to compare the predictive performance of two established PopPK models from their respective data. Differences in datasets for model building (including sample size, sampling schedule and route of administration), model structure and parameters, and key derived exposure metrics were compared, and the resulting differences in model prediction were elaborated. With the majority of the data used for developing models being trough concentration (C_trough) data, both models projected similar C_trough and area under the concentration-time curve (AUC) but different peak concentrations (C_max) at steady state following the same subcutaneous dose regimen. Our case study supports the importance of appropriate sampling schemes for PopPK model development and exposure metric estimation. We recommend collecting proper random pharmacokinetic samples, in addition to troughs, to allow adequate characterization of PopPK models for mAbs. Selecting the informative model and relevant pharmacokinetic metrics could be critical in driving drug development decision-making, especially in simulation-based exposure matching to inform doses in special populations such as pediatrics.

The impact of hepatic and renal function on panitumumab exposures in patients with metastatic RAS wild-type colorectal cancer

Purpose

Panitumumab is a human monoclonal antibody targeting the epidermal growth factor receptor for the treatment of wild-type RAS metastatic colorectal cancer (mCRC). Currently, no dedicated clinical studies have evaluated the effect of organ impairment on the pharmacokinetics of panitumumab. Here, we present data from late phase studies of panitumumab in patients with mCRC and analyses of the effect of hepatic or renal impairment on the exposure of panitumumab.

Methods

From three multicenter, open-label, phase 2 and phase 3 studies, 349 and 351 patients were included in hepatic and renal function subgroup analyses, respectively. Patients who received IV panitumumab and serum exposures were compared to patients with varying degrees of hepatic and renal organ dysfunction.

Results

The C_max and C_trough values for patients with mild (n = 119) and moderate (n = 4) hepatic impairment were within the range of serum concentrations of panitumumab for the normal hepatic function subgroup. The distributions of serum concentration of panitumumab in patients with mild (n = 85) or moderate (n = 19) renal impairment were similar to the serum concentrations of panitumumab in the normal renal function subgroup. Population pharmacokinetic modeling and covariate analysis results were also consistent with lack of any significant effect of renal or hepatic impairment on the pharmacokinetics of panitumumab. Additionally, real-world evidence from case studies of patients with mCRC and severe hepatic or renal impairment, which is a rare patient population to study, indicated lack of clinically relevant differences in exposure of panitumumab compared with patients with mCRC and normal hepatic or renal function.

Conclusions

Mild-to-moderate hepatic or renal dysfunction had no clinically meaningful impact on the pharmacokinetics of panitumumab in patients with mCRC. No dose adjustments for panitumumab are warranted in patients with mCRC with mild-to-moderate hepatic or renal dysfunction.

Trial registration

ClinicalTrials.gov; NCT00083616, NCT00089635, NCT00113763

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-021-04319-w.

Deciphering adverse drug reactions: in vitro priming and characterization of vancomycin-specific T-cells from healthy donors expressing HLA-A*32:01

Drug rash with eosinophilia with systemic symptoms (DRESS) is a serious adverse event associated with use of the glycopeptide antibiotic vancomycin. Vancomycin-induced drug rash with eosinophilia with systemic symptoms is associated with the expression of human leukocyte antigen (HLA)-A*32:01, suggesting that the drug interacts with this HLA to activate CD8+ T cells. The purpose of this study was to utilize peripheral blood mononuclear cell from healthy donors to: (1) investigate whether expression of HLA-A*32:01 is critical for the priming naïve of T cells with vancomycin and (2) generate T-cell clones (TCC) to determine whether vancomycin exclusively activates CD8+ T cells and to define cellular phenotype, pathways of drug presentation and cross-reactivity. Dendritic cells were cultured with naïve T cells and vancomycin for 2 weeks. On day 14, cells were restimulated with vancomycin and T-cell proliferation was assessed by [³H]-thymidine incorporation. Vancomycin-specific TCC were generated by serial dilution and repetitive mitogen stimulation. Naïve T cells from HLA-A*02:01 positive and negative donors were activated with vancomycin; however the strength of the induced response was significantly stronger in donors expressing HLA-A*32:01. Vancomycin-responsive CD4+ and CD8+ TCC from HLA-A*32:01+ donors expressed high levels of CXCR3 and CCR4, and secreted IFN‐γ, IL-13, and cytolytic molecules. Activation of CD8+ TCC was HLA class I-restricted and dependent on a direct vancomycin HLA binding interaction with no requirement for processing. Several TCC displayed cross-reactivity with teicoplanin and daptomycin. To conclude, this study provides evidence that vancomycin primes naïve T cells from healthy donors expressing HLA-A*32:01 through a direct pharmacological binding interaction. Cross-reactivity of CD8+ TCC with teicoplanin provides an explanation for the teicoplanin reactions observed in vancomycin hypersensitive patients.

Immune Checkpoint and Anti-Angiogenic Antibodies for the Treatment of Non-Small Cell Lung Cancer in the European Union and United States

Several types of antibodies (Abs) are currently used in non-small cell lung cancer (NSCLC). Anti-angiogenic and immune checkpoint inhibitor (ICI) Abs are the most frequent treatments used alone or with chemotherapy in metastatic NSCLC, for the front line and beyond. Considering the many therapeutic options for locally advanced and metastatic lung cancer and differences in use according to geographic area, we present here a comprehensive review of the marketed ICI and anti-angiogenic Abs approved in the European Union (EU) and the US to treat locally advanced and metastatic NSCLC patients. We briefly describe the different molecules and their development in thoracic oncology and compare pharmacokinetic data, processing decision algorithms and marketing authorizations by the EMA and US Food and Drug Administration (FDA).

T cell mediated hypersensitivity to previously tolerated iodinated contrast media precipitated by introduction of atezolizumab

Many adverse reactions associated with immune checkpoint inhibitor (ICI) treatments are immunologically driven and may necessitate discontinuation of the ICI. Herein, we present a patient who had been administered the radio contrast media amidotrizoate multiple times without issue but who then developed a Stevens-Johnson syndrome reaction after coadministration of atezolizumab. Causality was confirmed by a positive re-challenge with amidotrizoate and laboratory investigations that implicated T cells. Importantly, the introduction of atezolizumab appears to have altered the immunologic response to amidotrizoate in terms of the tolerance–elicitation continuum. Proof of concept studies demonstrated enhancement of recall responses to a surrogate antigen panel following in-vitro (healthy donors) and in-vivo (ICI patients) administrations of ICIs. Our findings highlight the importance of considering all concomitant medications in patients on ICIs who develop immune-mediated adverse reactions. In the event of some immune-related adverse reactions, it may be critical to identify the culprit antigen-forming entity that the ICIs have altered the perception of rather than simply attribute causality to the ICI itself in order to optimize both patient safety and treatment of malignancies.

Peptidomimetics Therapeutics for Retinal Disease

Ocular disorders originating in the retina can result in a partial or total loss of vision, making drug delivery to the retina of vital importance. However, effectively delivering drugs to the retina remains a challenge for ophthalmologists due to various anatomical and physicochemical barriers in the eye. This review introduces diverse administration routes and the accordant pharmacokinetic profiles of ocular drugs to aid in the development of safe and efficient drug delivery systems to the retina with a focus on peptidomimetics as a growing class of retinal drugs, which have great therapeutic potential and a high degree of specificity. We also discuss the pharmacokinetic profiles of small molecule drugs due to their structural similarity to small peptidomimetics. Lastly, various formulation strategies are suggested to overcome pharmacokinetic hurdles such as solubility, retention time, enzymatic degradation, tissue targeting, and membrane permeability. This knowledge can be used to help design ocular delivery platforms for peptidomimetics, not only for the treatment of various retinal diseases, but also for the selection of potential peptidomimetic drug targets.

Strategies to better treat glioblastoma: antiangiogenic agents and endothelial cell targeting agents

Glioblastoma multiforme (GBM) is the most prevalent and aggressive form of glioma, with poor prognosis and high mortality rates. As GBM is a highly vascularized cancer, antiangiogenic therapies to halt or minimize the rate of tumor growth are critical to improving treatment. In this review, antiangiogenic therapies, including small-molecule drugs, nucleic acids and proteins and peptides, are discussed. The authors further explore biomaterials that have been utilized to increase the bioavailability and bioactivity of antiangiogenic factors for better antitumor responses in GBM. Finally, the authors summarize the current status of biomaterial-based targeting moieties that target endothelial cells in GBM to more efficiently deliver therapeutics to these cells and avoid off-target cell or organ side effects.

Cell-Based Delivery Approaches for DNA-Binding Domains to the Central Nervous System

Advancements in programmable DNA-Binding Proteins (DBDs) that target the genome, such as zinc fingers, transcription activator-like effectors, and Cas9, have broadened drug target design beyond traditional protein substrates. Effective delivery methodologies remain a major barrier in targeting the central nervous system. Currently, adeno-associated virus is the most wellvalidated delivery system for the delivery of DBDs towards the central nervous with multiple, ongoing clinical trials. While effective in transducing neuronal cells, viral delivery systems for DBDs remain problematic due to inherent viral packaging limits or immune responses that hinder translational potential. Direct administration of DBDs or encapsulation in lipid nanoparticles may provide alternative means towards delivering gene therapies into the central nervous system. This review will evaluate the strengths and limitations of current DBD delivery strategies in vivo. Furthermore, this review will discuss the use of adult stem cells as a putative delivery vehicle for DBDs and the potential advantages that these systems have over previous methodologies.

Immune checkpoint inhibition in syngeneic mouse cancer models by a silicasome nanocarrier delivering a GSK3 inhibitor

Checkpoint blocking antibodies that interfere in the PD-1/PD-L1 axis provide effective cancer immunotherapy for tumors that are immune inflamed or induced to become "hot". It has also been demonstrated that a small molecule inhibitor of the signaling hub kinase GSK3 can interfere in the PD-1/PD-L1 axis in T-cells by suppressing PD-1 expression. This provides an alternative approach to intervening in the PD-1/PD-L1 axis to provide cancer immunotherapy. In this communication, we demonstrate the remote loading of GSK3 inhibitor AZD1080 into the porous interior of mesoporous silica nanoparticles coated with a lipid bilayer (a.k.a. silicasomes). In a MC38 colon cancer model, intravenous injection (IV) of silicasome-encapsulated AZD1080 significantly improved biodistribution and drug delivery to the tumor site. The improved drug delivery was accompanied by cytotoxic MC38 tumor cell killing by perforin-releasing CD8⁺ T-cells, exhibiting reduced PD-1 expression. IV injection of encapsulated AZD1080 also resulted in significant tumor shrinkage in other syngeneic mouse tumor models, including another colorectal tumor (CT26), as well as pancreas (KPC) and lung (LLC) cancer models. Not only was the therapeutic efficacy of encapsulated AZD1080 similar or better than anti-PD-1 antibody, but the treatment was devoid of treatment toxicity. These results provide proof-of-principal demonstration of the feasibility of using encapsulated delivery of a GSK3 inhibitor to provide cancer immunotherapy, with the possibility to be used as a monotherapy or in combination with chemotherapy or other immunomodulatory agents.

From cell line development to the formulated drug product: The art of manufacturing therapeutic monoclonal antibodies

Therapeutic monoclonal antibodies and related products have steadily grown to become the dominant product class within the biopharmaceutical market. Production of antibodies requires special precautions to ensure safety and efficacy of the product. In particular, minimizing antibody product heterogeneity is crucial as drug substance variants may impair the activity, efficacy, safety, and pharmacokinetic properties of an antibody, consequently resulting in the failure of a product in pre-clinical and clinical development. This review will cover the manufacturing and formulation challenges and advances of therapeutic monoclonal antibodies, focusing on improved processes to minimize variants and ensure batch-to-batch consistency. Processes put in place by regulatory agencies, such as Quality-by-Design (QbD) and current Good Manufacturing Practices (cGMP), and how their implementation has aided drug development in pharmaceutical companies will be reviewed. Advances in formulation and considerations on the intended use of a therapeutic antibody, including the route of administration and patient compliance, will be discussed.

Novel strategies in immune checkpoint inhibitor drug development: How far are we from the paradigm shift?

The development of immune checkpoint inhibitors (ICI) represents a major milestone in immune-oncology. Over the years these agents have demonstrated efficacy in an increasing array of malignancies. Despite this success however, significant challenges remain. Novel approaches to both drug development and trial design are required to incorporate the unique pharmacokinetic and pharmacodynamic properties of ICIs. Further, it has also been established that the benefit of ICIs is limited to only a subset of patients. The molecular interactions between native immune cells and tumorigenesis and progression represent an active area of biomarker research, and elucidating the mechanisms of response and resistance is crucial to develop rational trial designs for the next wave of immune-oncology (IO) clinical trials, particularly in patients with primary and/or acquired resistance. Efforts are now being made to integrate both biological and clinical information using novel multi-omic approaches which are now being developed to further elucidate the molecular signatures associated with IO treatment response and resistance and enable rational drug development and trial design processes. As such, precision IO and the ability to deliver patient-specific choices for ICI monotherapies or combination therapies has become an increasingly tangible goal. We herein describe the current landscape in ICI drug development and discuss the challenges and future directions in this exciting and evolving era in immune-oncology.

Dose Regimen Rationale for Panitumumab in Cancer Patients: To Be Based on Body Weight or Not

Introduction

Body weight can affect exposure, safety and efficacy of antibody-based therapies; sometimes these effects may not be clinically relevant. Panitumumab is approved for wild-type RAS metastatic colorectal cancer, using a body weight–based dosing regimen. Recently, a report cited fixed-dose usage of panitumumab, rather than approved body weight–based dosing. The current work evaluates optimal dosing regimen scientifically based on clinical data, modeling and simulation. Herein, we assessed the effect of fixed and body weight–based dosing on panitumumab pharmacokinetics to determine which approach resulted in the least interpatient pharmacokinetic variability.

Patients and Methods

From the Vectibix program, 352 patients enrolled in three studies were evaluated; they had received panitumumab (body weight–based dose: 6 mg/kg every 2 weeks) and had pharmacokinetic (maximum serum [C_max] and trough [C_min] concentrations) and body weight data available. Additionally, concentration-time profiles at fixed (480 mg) and body weight–based doses (6 mg/kg) were simulated using a population pharmacokinetics model developed from 1200 patients.

Results

After administration of panitumumab 6 mg/kg, C_max and C_min increased with increasing body weight; the mean C_max and C_min for patients weighing <65 kg (lower quartile) were 23% and 30% lower, respectively, than for those weighing >88 kg (upper quartile). The simulated area under the concentration–time curve (AUC) data also indicated that overall panitumumab exposure increased with increasing body weight for the body weight–based regimen. When AUC was simulated for a fixed dose (480 mg), the opposite effect was observed. Over the range of body weights, interpatient variability in simulated AUC was lower for the weight-based dose (29%) than for the fixed dose (34%).

Conclusion

Results demonstrate that the weight-based dose (6 mg/kg) reduced variability in panitumumab exposure across the range of body weights compared with the fixed-dose approach, indicating that a body weight–based approach is the recommended patient dosing strategy.