Fixed Dosing of Monoclonal Antibodies in Oncology

Synergy of Body Composition, Exercise Oncology, and Pharmacokinetics: A Narrative Review of Personalizing Paclitaxel Treatment for Breast Cancer

BACKGROUND/OBJECTIVES

Paclitaxel is a type of small molecule chemotherapy widely used for breast cancer, but its clinical efficacy is often hindered by dose-limiting toxicities such as chemotherapy-induced peripheral neuropathy and neutropenia. Traditional dosing based on body surface area does not account for variations in body composition, which may influence paclitaxel metabolism, toxicity, and treatment outcomes. This review explores the interplay between body composition, physical activity, and paclitaxel pharmacokinetics, emphasizing the potential for personalized dosing strategies.

METHODS

A comprehensive narrative review was conducted by analyzing the literature on body composition, small molecule chemotherapy-related toxicities, pharmacokinetics, and exercise oncology. Studies examining the role of skeletal muscle mass, adipose tissue, and physical activity in modulating paclitaxel metabolism and side effects were included.

RESULTS

Evidence suggests that patients with low skeletal muscle mass are at a higher risk of paclitaxel-induced toxicities due to altered drug distribution and clearance. Sarcopenic obesity, characterized by low muscle and high-fat levels, further exacerbates these risks. Exercise, particularly resistance and aerobic training, has been shown to improve muscle mass, mitigate toxicities, and enhance chemotherapy tolerance. However, the precise mechanisms by which exercise influences paclitaxel pharmacokinetics remain underexplored.

CONCLUSIONS

Personalized chemotherapy dosing, considering body composition and physical activity, may optimize paclitaxel treatment outcomes. Future research should focus on integrating exercise interventions into oncology care and refining dosing models that account for interindividual differences in drug metabolism. These advancements could improve treatment efficacy while minimizing toxicities in breast cancer patients.

The benefits of Lactiplantibacillus plantarum: From immunomodulator to vaccine vector

Probiotics have been increasingly recognized for positively influencing many aspects of human health. Lactiplantibacillus plantarum (L. plantarum), a non-pathogenic bacterium, previously known as Lactobacillus plantarum, is one of the lactic acid bacteria commonly used in fermentation. The probiotic properties of L. plantarum have highlighted its health benefits to humans when consumed in adequate amounts. L. plantarum strains primarily enter the body orally and alter intestinal microflora and modulate the immune responses in their host; thereby benefiting human health. Furthermore, the use of L. plantarum as vaccine vectors delivering mucosal antigens has been shown to be a promising strategy. These aspects, from Immunomodulation to vaccine delivery by L. plantarum in preclinical settings, are highlighted in this review. Along these lines, construction of a recombinant L. plantarum strain expressing a B cell multi-peptide, as a future vaccine to modulate immunity and confer anti-tumor effect by targeting Her-2/neu-overexpressing cancers in local and distal sites, is also presented and discussed.

Pembrolizumab hybrid dosing is non-inferior to flat dosing in advanced non-small cell lung cancer: a real-world, retrospective bicenter cohort study

BACKGROUND

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment but come with high costs. Alternative ICI dosing strategies could reduce costs without losing efficacy. However, clinical efficacy data are lacking.

METHODS

In this retrospective cohort trial, consecutive patients with advanced non-small cell lung cancer (NSCLC) who received ≥1 cycle pembrolizumab±chemotherapy at two tertiary institutions were included. Hybrid dosed patients received either 100, 150 or 200 mg pembrolizumab every 3 weeks or double every 6 weeks depending on their weight: <65 kg, 65-90 kg or >90 kg, respectively. Standard-of-care flat dosed patients received 200 mg every 3 weeks or 400 mg every 6 weeks. Overall survival (OS) and progression-free survival (PFS) were assessed by Kaplan-Meier estimation, compared by log-rank test and HRs were calculated with the Cox proportional hazards model in both unweighted and inverse probability of treatment weighted (IPTW) cohorts. Non-inferiority margin was set at an HR of 1.15.

RESULTS

In total, 375 patients and 391 patients were included and median follow-up was 43.1 and 61.0 months in the hybrid and flat dose cohort, respectively. OS was non-inferior in the hybrid dose cohort compared with the flat dose cohort: median 17.7 months (95% CI 14.9 to 20.9) vs 11.8 months (95% CI 9.3 to 13.8, HR 0.76, 95% CI 0.65 to 0.90, p<0.0001 for non-inferiority). After correcting for confounders by IPTW, OS remained non-inferior (HR 0.76, 95% CI 0.63 to 0.91, p<0.0001 for non-inferiority). PFS in the hybrid cohort was also non-inferior to the flat dose cohort with a median of 6.4 months (95% CI 5.7 to 7.7) vs 4.6 months (95% CI 3.9 to 5.5, HR 0.82, 95% CI 0.70 to 0.96, p<0.0001 for non-inferiority). In total, 26.2% (or 52.5 mg per cycle, p<0.0001) pembrolizumab was saved in the hybrid dose cohort accounting to US$36 331.36 per patient.

CONCLUSIONS

In this retrospective analysis of a large cohort of advanced NSCLC patients treated with pembrolizumab±chemotherapy, OS of hybrid dosed patients was non-inferior to flat dosed patients. OS remained non-inferior after correcting for possible confounding factors. This hybrid regimen resulted in significant savings of pembrolizumab and costs.

Pharmacokinetics of Nivolumab and Erythropoietin in a Rat Model of Diet-Induced Obesity

PURPOSE

To investigate how obesity affects the pharmacokinetics of biologics in a rat model.

METHOD

Male Long-Evans rats were fed a high-fat diet from the age of 3 weeks and development of obesity was monitored by measuring body size and composition (fat and lean mass). The animals received nivolumab (1 and 8 mg/kg) or recombinant human erythropoietin (rHuEPO, 1000 IU/kg) by intravenous or subcutaneous injection. Serum samples were collected and analyzed using an enzyme-linked immunosorbent assay (ELISA). Endogenous rat IgG was also measured in the nivolumab study. A standard noncompartmental analysis was performed to calculate pharmacokinetic parameters.

RESULTS

When dosed at mg/kg of total body weight approach, no significant differences in pharmacokinetics of nivolumab and rHuEPO between lean and obese cohorts were observed despite significant differences in the body composition. Subcutaneous bioavailability of nivolumab was inversely dependent on the dose level.

CONCLUSIONS

Pharmacokinetic parameters of two biologics tested in this work were not affected by obesity, and mg/kg dosing approach was necessary to achieve equivalent exposure in serum. The results were different from our previous findings of significant effect of obesity on pharmacokinetics of human IgG in rats. Additional studies with other biologics are urgently needed in preclinical and clinical settings.

First-in-Human Study of 23ME-00610, an Antagonistic Antibody for Genetically Validated CD200R1 Immune Checkpoint, in Participants with Advanced Solid Malignancies

PURPOSE

In this phase 1 portion of a first-in-human phase 1/2a study (NCT05199272), 23ME-00610 was evaluated in participants with advanced solid malignancies to determine its safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD). Exploratory biomarkers were evaluated to examine potential correlates of efficacy and safety.

PATIENTS AND METHODS

Eligible participants (≥18 years) were administered 23ME-00610 intravenously every 3 weeks (Q3W) using an accelerated titration design followed by a traditional 3 + 3 design, with an initial dose level of 2 mg.

RESULTS

Twenty-eight participants were enrolled across seven cohorts and received a median of four cycles of 23ME-00610. No treatment-related serious adverse events (AE) were observed, and the maximum tolerated dose was not reached. Overall, the PK of 23ME-00610 was linear and dose proportional for doses ≥60 mg, with a median terminal half-life of 13 days at 1,400 mg. Peripheral saturation of CD200R1 was observed for doses ≥60 mg. Immune-related AEs, including rash, pruritus, and hypothyroidism, were predicted by phenome-wide association studies and observed for doses ≥60 mg. A confirmed partial response was observed in a participant with well-differentiated pancreatic neuroendocrine cancer whose tumor was among those with the highest tumor CD200 expression.

CONCLUSIONS

23ME-00610 has mild-to-moderate on-target AEs and PK/PD consistent with tumor target saturation and dosing every 3 weeks. The trend for clinical benefit in participants with tumor CD200 expression suggests that 23ME-00610 inhibits CD200R1 signaling and may reverse CD200-mediated immune evasion. Based on PK/PD, safety, and preliminary antitumor activity, 1,400 mg Q3W was selected as the dose for further study.

SIGNIFICANCE

Genome-wide association studies (GWAS) of the 23andMe genetic database identified CD200R1 as a promising therapeutic target for cancer. This phase 1 study of 23ME-00610, a CD200R1 antagonist IgG1, showed acceptable safety and tolerability, PK supporting Q3W dosing, and PD and preliminary clinical activity supporting an initial recommended phase 2 dose of 1,400 mg.

Industry Perspective on First-in-Human and Clinical Pharmacology Strategies to Support Clinical Development of T-Cell Engaging Bispecific Antibodies for Cancer Therapy

T-cell-engaging bispecific antibodies (TCEs) that target tumor antigens and T cells have shown great promise in treating cancer, particularly in hematological indications. The clinical development of TCEs often involves a lengthy first-in-human (FIH) trial with many dose-escalation cohorts leading up to an early proof of concept (POC), enabling either a no-go decision or dose selection for further clinical development. Multiple factors related to the target, product, disease, and patient population influence the efficacy and safety of TCEs. The intricate mechanism of action limits the translatability of preclinical models to the clinic, thereby posing challenges to streamline clinical development. In addition, unlike traditional chemotherapy, the top dose and recommended phase II doses (RP2Ds) for TCEs in the clinic are often not guided by the maximum tolerated dose (MTD), but rather based on the integrated dose-response assessment of the benefit/risk profile. These uncertainties pose complex challenges for translational and clinical pharmacologists (PK/PD scientists), as well as clinicians, to design an efficient clinical study that guides development. To that end, experts in the field, under the umbrella of the American Association of Pharmaceutical Scientists, have reviewed learnings from published literature and currently marketed products to share perspectives on the FIH and clinical pharmacology strategies to support early clinical development of TCEs.

Navigating Recent Changes in Dosing Information: Dynamics of FDA-Approved Monoclonal Antibodies in Post-Marketing Realities

Monoclonal antibodies (mAbs) are critical components in the therapeutic landscape, but their dosing strategies often evolve post-approval as new data emerge. This review evaluates post-marketing label changes in dosing information for FDA-approved mAbs from January 2015 to September 2024, with a focus on both initial and extended indications. We systematically analyzed dosing modifications, categorizing them into six predefined groups: Dose increases or decreases, inclusion of new patient populations by body weight or age, shifts from body weight-based dosing to fixed regimens, and adjustments in infusion rates. Among the 86 mAbs evaluated, 21% (n = 18) exhibited changes in dosing information for the initial indication, with a median time to modification of 37.5 months (range: 5-76 months). Furthermore, for mAbs with extended indications (n = 26), 19.2% (n = 5) underwent dosing changes in their first extensions, with a median time to adjustment of 31 months (range: 8-71 months). Key drivers for these adjustments included optimizing therapeutic efficacy, addressing safety concerns, accommodating special populations, and enhancing patient convenience. We also discuss the role of model-informed drug development, real-world evidence, and pharmacogenomics in refining mAb dosing strategies. These insights underscore the importance of ongoing monitoring and data integration in the post-marketing phase, providing a foundation for future precision medicine approaches in mAb therapy.

Evaluation of the safety, tolerability, pharmacokinetics and pharmacodynamics of SM17 in healthy volunteers: results from pre-clinical models and a first-in-human, randomized, double blinded clinical trial

Background

Alarmins mediate type 2 T helper cell (Th2) inflammation and serve as upstream signaling elements in allergic inflammation and autoimmune responses. The alarmin interleukin (IL)-25 binds to a multi-domain receptor consisting of IL-17RA and IL-17RB subunits, resulting in the release of Th2 cytokines IL-4, IL-5, IL-9 and IL-13 to drive an inflammatory response. Therefore, the blockage of IL-17RB via SM17, a novel humanized monoclonal antibody, offers an attractive therapeutic target for Th2-mediated diseases, such as asthma.

Methods

Wild-type mice were stimulated with house dust mite (HDM) extracts for evaluation of SM17's pre-clinical efficacy in allergic asthma. The safety, pharmacokinectics (PK), pharmacodynamics (PD), and immunogenicity of intravenous (IV) doses of SM17 were assessed in a 2-part clinical study in healthy adult subjects. In Part A, 53 healthy participants were enrolled to receive a single IV dose of SM17 (2, 20, 70, 200, 400, 600, 1200 mg) or placebo. In Part B, 24 healthy subjects were enrolled to receive a single IV dose of SM17 every two weeks (Q2W; 200, 400, 600 mg) or placebo for a total of 3 doses.

Results

Animal studies demonstrated that SM17 significantly suppressed Th2 inflammation in the bronchoalveolar lavage fluid and infiltration of immune cells into the lungs. In the Phase I clinical study, no drug-related serious adverse events were observed. Total SM17 exposure increased by approximately 60- to 188-fold with a 60-fold increase in dose from 20 to 1200 mg SM17. Upon administration of the third dose, mean accumulation ratios over 200-600 mg was 1.5 to 2.1, which confirms moderate accumulation of SM17. After Q2W dosing of SM17 over 4 weeks, total exposure increased in a dose-proportional manner from 200 mg to 600 mg SM17.

Conclusion

In the pre-clinical studies, we demonstrated that SM17 is a potential therapeutic agent to treat allergic asthma. In the Phase 1 clinical trial, a single IV dose of SM17 up to 1200 mg and three Q2W doses up to 600 mg were well tolerated in healthy participants and demonstrated a favorable safety profile. The pre-clinical efficacy and clinical PK and immunogenicity results of SM17 support further clinical development.

Clinical trial registration

https://clinicaltrials.gov/, identifier NCT05332834.

Population pharmacokinetic model of ABL001/CTX-009 (anti-VEGF/DLL4) in adult cancer patients with solid tumor

ABL001/CTX-009 is a bispecific antibody targeting delta-like ligand-4 and vascular endothelial growth factor A. In this study, we developed a population pharmacokinetic (PK) model of ABL001/CTX-009 in patients with solid tumors. A total of 712 plasma concentrations from 30 patients with relapsed or refractory solid tumors were collected from a phase 1 study (NCT03292783). A population PK model was developed using a nonlinear mixed-effect method and was evaluated by graphical and numerical methods. Using the model, the steady-state concentrations were simulated to compare weight-based and fixed-dose regimens and to find optimal dosing intervals. The PK of ABL001/CTX-009 was well described by a two-compartment model with a parallel first-order and Michaelis-Menten elimination kinetics. Body weight was selected as a significant covariate on V1. Model evaluation results suggested that the model was adequate and robust with good precision. Simulations after administrations of fixed or weight-based doses showed similar plasma concentrations. Additionally, 10 mg/kg for every other week and 15 mg/kg for every three-week administration showed comparable plasma concentrations. In conclusion, the model well described the plasma concentrations of ABL001/CTX-009 in patients with solid tumors. The simulation suggested that weight-based dose and fixed dose can provide equivalent systemic exposure.

Population Pharmacokinetic Modeling and Exposure-Response Analysis for the Antibody-Drug Conjugate Enfortumab Vedotin in Locally Advanced or Metastatic Urothelial Carcinoma

Enfortumab vedotin is a fully human monoclonal antibody directed to Nectin-4 and conjugated to monomethyl auristatin E (MMAE), approved for treatment of previously treated locally advanced or metastatic urothelial carcinoma (mUC). This population analysis characterized pharmacokinetics of enfortumab vedotin and free (unconjugated) MMAE, identified covariates affecting pharmacokinetics, and evaluated weight-based dosing for enfortumab vedotin. Exposure-response analyses characterized relationships between enfortumab vedotin and free MMAE exposures and efficacy/safety endpoints. Data from 748 patients with locally advanced or mUC in 5 clinical studies were analyzed using nonlinear mixed-effects modeling. Patients received enfortumab vedotin 0.50-1.25 mg/kg every 3 weeks or on days 1, 8, and 15 of a 28-day cycle. Relevant covariates retained in final models were evaluated for clinical relevance to enfortumab vedotin and free MMAE exposures. Although some covariates produced differences in exposure, the magnitude of changes was not clinically meaningful. Simulations indicated weight-based dosing yielded more consistent exposures across body weight groups vs. a hypothetical fixed-dose regimen of enfortumab vedotin 95 mg (calculated for median body weight, 75 kg). Exposure-response analysis showed average enfortumab vedotin concentrations were not a statistically significant predictor of overall survival (hazard ratio 0.91, 95% confidence interval: 0.72-1.14; P = 0.41); all exposure quartiles had a greater median overall survival than chemotherapy (11.0-12.6 vs. 9.0 months). Enfortumab vedotin and free MMAE exposures were statistically significant predictors of grade ≥ 3 treatment-related adverse events (both P < 0.0001). This analysis supports enfortumab vedotin 1.25 mg/kg on days 1, 8, and 15 of a 28-day cycle.

Safety of solid oncology drugs in older patients: a narrative review

The older population represents ∼50%-60% of the population of newly diagnosed patients with cancer. Due to physiological and pathological aging and the increased presence of comorbidities and frailty factors, this population is at higher risk of serious toxicity from anticancer drugs and, consequently, often under-treated. Despite the complexity of these treatments, a good knowledge of the pharmacology of anticancer drugs and potentially risky situations can limit the emergence of potentially lethal toxicities in this population. This review focuses on optimizing systemic oncology treatments for older patients, emphasizing the unique characteristics of each therapeutic class and the necessity for a precautionary approach for this vulnerable population.

Pharmacokinetics of Subcutaneous Itepekimab Injection With an Autoinjector Device and Prefilled Syringe in Healthy Participants

Itepekimab, a monoclonal antibody against interleukin-33, has demonstrated clinical utility in previous studies in patients with asthma and chronic obstructive pulmonary disease. An autoinjector (AI) has been developed for administering itepekimab to facilitate further development. This study compared pharmacokinetics of single 300-mg itepekimab subcutaneous administration via an AI versus a prefilled syringe (PFS). Of 90 healthy volunteers enrolled in this Phase 1, parallel-design, randomized study and stratified by body weight (50 to <70 kg, ≥70 to <80 kg, ≥80 to 100 kg) and injection site (abdomen, thigh, or arm), 84 completed the study. Systemic exposure of itepekimab was similar for both groups. Point estimates for geometric mean ratios of pharmacokinetic parameters for AI versus PFS groups were 1.01 for maximum serum concentration, 1.06 for area under the serum concentration-time curve to the last quantifiable concentration, and 1.04 for area under the serum concentration-time curve extrapolated to infinity. The exposure was similar for both devices in each body weight and injection site subgroup. Overall, systemic exposure of 300-mg single-dose itepekimab in healthy participants was comparable when administered subcutaneously via an AI device and PFS, with an acceptable safety profile in both device groups.

Phase II Trial of HER-Vaxx, a B-cell Peptide-Based Vaccine, in HER2-Overexpressing Advanced Gastric Cancer Patients Under Platinum-Based Chemotherapy (HERIZON)

PURPOSE

A multicenter, randomized, open-label, phase II study (HERIZON; NCT02795988) was conducted to evaluate the clinical and immunologic efficacy of HER-Vaxx (IMU-131), a B-cell, peptide-based vaccine targeting HER2 overexpressed in 6% to 30% of gastroesophageal adenocarcinomas (GEA).

PATIENTS AND METHODS

Patients (n = 36) with GEA were treated with standard-of-care chemotherapy (n = 17) or HER-Vaxx plus chemotherapy (n = 19), using the recommended phase 2 dose for the vaccine. Overall survival (OS; primary endpoint), safety, progression-free survival (PFS), clinical response (secondary endpoints), and vaccine-induced HER2-specific antibody levels in serum and correlation with tumor response rates (exploratory endpoints) were investigated.

RESULTS

A 40% OS benefit [HR, 0.60; median OS, 13.9 months; 80% confidence interval (CI), 7.52-14.32] for patients treated with HER-Vaxx plus chemotherapy compared with OS of 8.31 months (80% CI, 6.01-9.59) in patients that received chemotherapy alone. A 20% PFS difference was obtained for the vaccination arm (HR, 0.80; 80% CI, 0.47, 1.38). No additional toxicity due to HER-Vaxx was observed. The vaccine-induced high levels of HER2-specific total IgG and IgG1 antibodies (P < 0.001 vs. controls) that significantly correlated with tumor reduction (IgG, P = 0.001; IgG1, P = 0.016), had a significant capacity in inhibiting phosphorylation of the intracellular HER2-signaling pathways, mediated antibody-dependent cellular cytotoxicity, and decreased immunosuppressive FOXP3+ regulatory T cells.

CONCLUSIONS

HER-Vaxx plus standard chemotherapy exhibits an excellent safety profile and improves OS. Furthermore, vaccine-induced immune response was significantly associated with reduced tumor size compared with standard-of-care chemotherapy. The presented vaccination approach may substitute for treatment with trastuzumab, upon unavailability or toxicity, based on further evidence of equivalent treatment efficacy.

A phase III study to access the safety and efficacy of prolgolimab 250 mg fixed dose administered every 3 weeks versus prolgolimab 1 mg/kg every 2 weeks in patients with metastatic melanoma (FLAT)

Background

Prolgolimab is the first Russian PD-1 inhibitor approved for the first-line treatment of unresectable or metastatic melanoma and advanced non-small cell lung cancer. It was approved in two weight-based regimens of 1 mg/kg Q2W and 3 mg/kg Q3W, but because of re-evaluation of weight-based dosing paradigm, studying of a fixed-dose regimen was considered perspective.

Methods

We conducted a multicenter, single-arm, open-label efficacy, pharmacokinetics, and safety study to obtain data that would allow the approval of the new flat dosing regimen of prolgolimab in patients with previously untreated unresectable or metastatic melanoma (BCD-100-8/FLAT, NCT05783882). The primary objective was to prove the non-inferiority of prolgolimab 250 mg Q3W versus prolgolimab 1 mg/kg Q2W for the treatment of patients with unresectable or metastatic melanoma in terms of ORR according to RECIST 1.1. Patients from the MIRACULUM study (BCD-100-2/MIRACULUM, NCT03269565) comprised a historical control group.

Results

One hundred fourteen patients received prolgolimab 250 mg Q3W, and 61 patients received prolgolimab (Prolgo) 1 mg/kg Q2W (historical control). Objective response was achieved by 33.3% [95% confidence interval (CI): 24.8, 42.8] of patients in the Prolgo 250 mg group compared with 32.8% (95% CI: 21.3, 46.0) of patients in the Prolgo 1 mg/kg group. Risk difference was 0.00, 95% CI (-0.12; NA), p = 0.0082. Both regimens were well tolerated, and safety profiles were comparable. The pharmacokinetic analysis (PK) showed that the regimen with the fixed dose of 250 mg Q3W was characterized by higher PK parameters. The immunogenicity study did not detect binding antibodies to prolgolimab in any of the subjects.

Conclusion

The obtained results showed that the selected fixed dosing regimen of prolgolimab 250 mg Q3W is characterized by efficacy and safety parameters comparable to that observed for the 1 mg/kg Q2W regimen.

An Evidence-Based Rationale for Dose De-escalation of Subcutaneous Atezolizumab

BACKGROUND

Atezolizumab is a programmed death-ligand 1 (PD-L1) checkpoint inhibitor for the treatment of different forms of cancer. The subcutaneous formulation of atezolizumab has recently received approval. However, treatment with atezolizumab continues to be expensive, and the number of patients needing treatment with this drug continues to increase.

OBJECTIVE

We propose two alternative dosing regimens for subcutaneous atezolizumab to reduce drug expenses while ensuring effective exposure; one may be directly implemented in the clinic.

PATIENTS AND METHODS

We developed two alternative dose interval prolongation strategies based on pharmacokinetic modeling and simulation. The first dosing regimen was based on patients' weight while maintaining equivalent systemic drug exposure by adhering to Food and Drug Administration (FDA) guidelines for in silico dose adjustments. The second dosing regimen aimed to have a minimum atezolizumab concentration above the 6 µg/mL threshold, associated with 95% intratumoral PD-L1 receptor saturation for at least 95% of all patients.

RESULTS

We found that, for the weight-based dosing regimen, the approved 3-week dosing interval could be extended to 5 weeks for patients < 50 kg and 4 weeks for patients weighing 50-65 kg. Besides improving patient convenience, these alternative dosing intervals led to a predicted 7% and 12% cost reduction for either the USA or European population. For the second dosing regimen, we predicted that a 6-week dosing interval would result in 95% of the patients above the 6 µg/mL threshold while reducing costs by 50%.

CONCLUSIONS

We have developed and evaluated two alternative dosing regimens that resulted in a cost reduction. Our weight-based dosing regimen can be directly implemented and complies with FDA guidelines for alternative dosing regimens of PD-L1 inhibitors. For the more progressive alternative dosing regimen aimed at the intratumoral PD-L1 receptor threshold, further evidence on efficacy and safety is needed before implementation.

Prolonged in-use physicochemical and biological stability of nivolumab and pembrolizumab diluted in saline infusion bags and in partially used medication vials

AIM/BACKGROUND

The aim of this study was to determine long-term physicochemical and biological stability of nivolumab and pembrolizumab diluted in saline infusion bags and partially used medication vials. This may enable the prolonged clinical use of these expensive monoclonal antibodies (mAbs) to minimize the economic loss.

METHODS

Sterile nivolumab and pembrolizumab concentrates in partially used medication vials and compounded nivolumab and pembrolizumab infusion solutions were stored for two and four weeks, respectively, at 2-8°C in the dark. Subsequently, concentrates and compounded solutions were stored for an additional two weeks under ambient temperature and light conditions. A panel of validated and complementary methods, consisting of enzyme-linked immunosorbent assay, size exclusion chromatography, and dynamic light scattering, were used to assess the biological and physiochemical stability of these mAbs.

RESULTS

All samples showed that purity and concentration had remained within the criteria of <5% as stated in the European Pharmacopoeia. Diluted in infusion bags, nivolumab and pembrolizumab remained biologically and physiochemically stable for up to four weeks when stored at 2-8°C in the dark with an additional two weeks of ambient temperature and light. Stability in partially used medication vials was demonstrated for at least two weeks when stored at 2-8°C in the dark with an additional two weeks of ambient temperature and light.

CONCLUSION

The findings of this study justify the storage and clinical re-use of sterile nivolumab and pembrolizumab in partially used medication vials and compounded IV infusion bags for up to six weeks. This minimizes the risk of economic loss due to waste. Moreover, these findings support the batch-wise compounding of fixed-dose and dose-banded nivolumab and pembrolizumab infusion bags.

Comparing long-term prognosis following different surgical methods in patients with early stage breast cancer and obesity: a retrospective cohort study in China

OBJECTIVE

Breast-conserving therapy (BCT) includes breast-conserving surgery (BCS) combined with radiation therapy (RT). RT plays a crucial role in improving the prognosis of patients who undergo BCS. However, obesity is a potential risk factor for resistance to radiation. The aim of this study was to evaluate any difference in the long-term prognosis of patients with early stage breast cancer and obesity treated with BCT or total mastectomy (TM).

DESIGN, SETTING AND PARTICIPANTS

This was a retrospective cohort study involving 1125 patients diagnosed with early stage breast cancer and obesity at the Shanghai Cancer Center of Fudan University from 2013 to 2016.

OUTCOME MEASURES

Obesity in the Chinese population was defined as a body mass index ≥28 kg/m2. Surgical options included BCT and TM. The primary survival outcomes were overall survival (OS), disease-free survival (DFS) and recurrence-free survival (RFS). Inverse probability of treatment weighting (IPTW) was used to control for the impact of confounding factors on prognosis.

RESULTS

The median follow-up times in the BCT group and TM group without postoperative RT were 51.1 months (IQR of 40.6-68.1 months) and 61.8 months (IQR of 46.5-76.7 months), respectively. After IPTW, the baseline data were balanced. Compared with those in the TM cohort, patients in the whole IPTW cohort in the BCT cohort had worse DFS (HR 4.280, 95% CI 2.180 to 8.400; p<0.001), RFS (HR 4.380, 95% CI 2.370 to 8.120; p<0.001) and OS (HR 3.590, 95% CI 1.620 to 7.950; p=0.002).

CONCLUSION

In patients with early stage breast cancer and obesity, TM is associated with better survival outcomes than BCT.

First-in-Human Study of the Safety, Tolerability, Pharmacokinetics, Immunogenicity, and Pharmacodynamics of DS-7011a, an Anti-TLR7 Antagonistic Monoclonal Antibody for the Treatment of Systemic Lupus Erythematosus

Toll-like receptor (TLR)7 is a pattern recognition receptor that critically contributes to the pathogenesis of systemic lupus erythematosus (SLE). DS-7011a is an anti-TLR7 monoclonal antibody that prevents TLR7 from signaling. The aim of this first-in-human, double-blind, randomized, and placebo-controlled study was to evaluate the safety, pharmacokinetics, immunogenicity, and pharmacodynamics of single ascending intravenous (IV) and subcutaneous (SC) doses of DS-7011a in healthy subjects (HS) (NCT05203692). On day 1, 80 HS received DS-7011a or placebo 6:2 in 10 cohorts (7 treated IV and 3 SC) of 8 each and were followed for 8 weeks until day 57. Safety was evaluated by recording treatment-emergent adverse events (TEAEs), pharmacokinetics by measuring plasma DS-7011a, immunogenicity by measuring plasma anti-drug antibodies (ADAs), and pharmacodynamics by evaluating the suppression of interleukin-6 production ex vivo in whole blood. DS-7011a was safe and well tolerated across all cohorts. TEAEs were mostly mild in severity and not drug-related. DS-7011a exposure increased with the dose but was not dose proportional, as the elimination of lower doses was accelerated by target-mediated drug disposition. Terminal half-life was about 15-17 days and Tmax upon SC administration was about 5 days. DS-7011a induced ADAs in about half of HS but with no impact on clinical findings and pharmacokinetics. Pharmacodynamic (PD) response also increased with the dose and at the higher doses was of large extent (>90%), early onset, and lasting duration. DS-7011a showed favorable safety, pharmacokinetics, immunogenicity, and PD properties that support its development for the treatment of SLE.

Performance evaluation of the HPLC diode array and evaporative light scattering detection for the implementation of dose-banded gemcitabine infusion bags

BACKGROUND

Dose banding (DB) was used to optimise the individualisation of patient treatments with gemcitabine (Gem) in order to improve workload planning at the pharmacy of the University Hospital Centre of Besançon (UHCB). A new simple and fast high-performance liquid chromatographic (HPLC) method was also developed for the quantification of Gem without dilution of the infusion bags.

METHODS

Individual doses of Gem preparations were retrospectively analysed over a 1-year period to determine the frequency of prepared doses. Using a maximum gap of 7.5% around the doses chosen, the selected Gem standard doses were 1400 mg, 1600 mg, 1800 mg and 2000 mg. Following the DB scheme, the frequency of prescription of standard and individualised Gem doses was analysed over a period of 10 months. The four selected Gem standard doses were aseptically prepared in polyolefin infusion bags. Each series of 20 bags was stocked under refrigerated storage conditions (4°C) for up to 84 days. The quantification of Gem without dilution of the infusion bags was obtained by the development of a HPLC method coupled to a diode array detector (DAD) or an evaporative light scattering detector (ELSD).

RESULTS

During the 10-month period following implementation of the DB, 75.6% of the 1266 prescribed doses were covered by the four standardised preparations. The number of different Gem doses was reduced from 183 to 55. Concerning the Gem quantification, both heteroscedasticity and non-linearity were observed with DAD. Using an ELSD, the trueness values were between 98.59% and 101.52% with excellent repeatability values between 0.66% and 1.42%.

CONCLUSION

A new HPLC method has been developed for the quantification of Gem without dilution of the infusion bags prepared in advance as a result of a target DB scheme successfully implemented in our pharmacy department.

Reporting on patient's body mass index (BMI) in recent clinical trials for patients with breast cancer: a systematic review

BACKGROUND

The proportion of patients with breast cancer and obesity is increasing. While the therapeutic landscape of breast cancer has been expanding, we lack knowledge about the potential differential efficacy of most drugs according to the body mass index (BMI). Here, we conducted a systematic review on recent clinical drug trials to document the dosing regimen of recent drugs, the reporting of BMI and the possible exclusion of patients according to BMI, other adiposity measurements and/or diabetes (leading comorbidity of obesity). We further explored whether treatment efficacy was evaluated according to BMI.

METHODS

A search of Pubmed and ClinicalTrials.gov was performed to identify phase I-IV trials investigating novel systemic breast cancer treatments. Dosing regimens and exclusion based on BMI, adiposity measurements or diabetes, documentation of BMI and subgroup analyses according to BMI were assessed.

RESULTS

495 trials evaluating 26 different drugs were included. Most of the drugs (21/26, 81%) were given in a fixed dose independent of patient weight. BMI was an exclusion criterion in 3 out of 495 trials. Patients with diabetes, the leading comorbidity of obesity, were excluded in 67/495 trials (13.5%). Distribution of patients according to BMI was mentioned in 8% of the manuscripts, subgroup analysis was performed in 2 trials. No other measures of adiposity/body composition were mentioned in any of the trials. Retrospective analyses on the impact of BMI were performed in 6 trials.

CONCLUSIONS

Patient adiposity is hardly considered as most novel drug treatments are given in a fixed dose. BMI is generally not reported in recent trials and few secondary analyses are performed. Given the prevalence of patients with obesity and the impact obesity can have on pharmacokinetics and cancer biology, more attention should be given by investigators and study sponsors to reporting patient's BMI and evaluating its impact on treatment efficacy and toxicity.

Albumin-ruthenium catalyst conjugate for bio-orthogonal uncaging of alloc group

The employment of antibodies as a targeted drug delivery vehicle has proven successful which is exemplified by the emergence of antibody-drug conjugates (ADCs). However, ADCs are not without their shortcomings. Improvements may be made to the ADC platform by decoupling the cytotoxic drug from the delivery vehicle and conjugating an organometallic catalyst in its place. The resulting protein-metal catalyst conjugate was designed to uncage the masked cytotoxin administered as a separate entity. Macropinocytosis of albumin by cancerous cells suggests the potential of albumin acting as the tumor-targeting delivery vehicle. Herein reported are the first preparation and demonstration of ruthenium catalysts with cyclopentadienyl and quinoline-based ligands conjugated to albumin. The effective uncaging abilities were demonstrated on allyloxy carbamate (alloc)-protected rhodamine 110 and doxorubicin, providing a promising catalytic scaffold for the advancement of selective drug delivery methods in the future.

Lung cancer, comorbidities, and medication: the infernal trio

Most patients with lung cancer are smokers and are of advanced age. They are therefore at high risk of having age- and lifestyle-related comorbidities. These comorbidities are subject to treatment or even polypharmacy. There is growing evidence of a link between lung cancer, comorbidities and medications. The relationships between these entities are complex. The presence of comorbidities and their treatments influence the time of cancer diagnosis, as well as the diagnostic and treatment strategy. On the other hand, cancer treatment may have an impact on the patient's comorbidities such as renal failure, pneumonitis or endocrinopathies. This review highlights how some comorbidities may have an impact on lung cancer presentation and may require treatment adjustments. Reciprocal influences between the treatment of comorbidities and anticancer therapy will also be discussed.

Non-neutralizing functions in anti-SARS-CoV-2 IgG antibodies

Most individuals infected with or vaccinated against COVID-19 develop antigenic neutralizing immunoglobulin G (IgG) antibodies against the SARS-CoV-2 spike protein. Although neutralizing antibodies are biomarkers of the adaptive immune response, their mere presence is insufficient to explain the protection afforded against the disease or its pathology. IgG exhibits other secondary effector functions that activate innate immune components, including complement, natural killer cells, and macrophages. The affinity for effector cells depends on the isotypes and glycosylation of IgG antibodies. The anti-spike IgG titer should be sufficient to provide significant Fc-mediated effects in severe COVID-19, mRNA, and protein subunit vaccinations. In combination with aberrant effector cells, pro-inflammatory afucosylated IgG1 and IgG3 may be detrimental in severe COVID-19. The antibody response of mRNA vaccines leads to higher fucosylation and a less inflammatory IgG profile, with a long-term shift to IgG4, which is correlated with protection from disease.

A robust optimal control framework for controlling aberrant RTK signaling pathways in esophageal cancer

This study presents a new framework for obtaining personalized optimal treatment strategies targeting aberrant signaling pathways in esophageal cancer, such as the epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) signaling pathways. A new pharmacokinetic model is developed taking into account specific heterogeneities of these signaling mechanisms. The optimal therapies are designed to be obtained using a three step process. First, a finite-dimensional constrained optimization problem is solved to obtain the parameters of the pharmacokinetic model, using discrete patient data measurements. Next, a sensitivity analysis is carried out to determine which of the parameters are sensitive to the evolution of the variants of EGF receptors and VEGF receptors. Finally, a second optimal control problem is solved based on the sensitivity analysis results, using a modified pharmacokinetic model that incorporates two representative drugs Trastuzumab and Bevacizumab, targeting EGF and VEGF, respectively. Numerical results with the combination of the two drugs demonstrate the efficiency of the proposed framework.

Fixed Versus Body-Sized-Based Dosing of Monoclonal Antibodies

Monoclonal antibody products are an increasing portion of novel drug approvals. The labeling of initial drug approvals frequently involves body-size-based rather than fixed-dose administration regimens for adults without clear rationale for doing so. This presents challenges when prescribing these products for patients with extremes of body habitus who constitute a small portion of enrollment in pre-approval investigations. Fixed-dose regimens allow for standardized preparation with the potential to reduce the risk of calculation errors, drug waste, and make home administration more practical. Fixed-dose rather than body-size-based monoclonal antibody regimens should serve as the initial approach in early phase 1 clinical trials.

Nivolumab and ipilimumab in the real-world setting in patients with mesothelioma

OBJECTIVES

Nivolumab (anti-PD-1) plus ipilimumab (anti-CTLA-4) is a new first-line treatment combination for patients with pleural mesothelioma. Nivolumab-ipilimumab improved the survival, however, 30.3% of the patients suffered from grade 3-4 treatment related adverse events (TRAE's) and TRAE's led to discontinuation in 23.0% of all patients. Here, we present the first real-world data of nivolumab plus ipilimumab in patients with malignant mesothelioma treated in two mesothelioma expert centers.

METHODS

Clinical data of patients with mesothelioma treated with nivolumab and ipilimumab were prospectively collected. Clinical parameters were obtained every visit, CT scans were evaluated every 12 weeks and adverse events were assessed continuously during the treatment. Data on grade 2-5 TRAE's and activity (overall response rate (ORR), duration of response (DOR), disease control rate (DCR), median progression-free survival (mPFS) and median overall survival (mOS) were reported.

RESULTS

Between January 2021 and August 2022, 184 patients were treated with nivolumab plus ipilimumab. The median follow-up was 12.1 months (95 %CI 11.1 - 13.1). Grade 3-4 TRAEs were seen in 27.7 % of the patients and 25.0 % discontinued immunotherapy treatment early because of TRAE's. ORR was 21.7 % (95 % CI 15.7-27.7), median DOR was 5.7 months (IQR 3.2-8.7) and DCR at 12 weeks 56.0 % (95 % CI 48.8-63.2). The mPFS was 5.5 months (95 %CI 4.1-6.9), mOS was 14.1 months (95 % CI 11.1-18.2).

CONCLUSIONS

Nivolumab plus ipilimumab had an equal efficacy in a real-world comparable population but also a high risk of TRAE's, leading to discontinuation of treatment in 25% of the patients.

Analysis of Medicare Expenditure for Discarded Infused Cancer Therapeutics From 2017-2020

OBJECTIVE

To explore patterns in Medicare reimbursement for wasted oncologic and hematologic infusion drugs from 2017 to 2020 and estimate the savings that implementation of the Infrastructure Investment and Jobs Act (IIJA) would have had.

METHODS

Using the publicly available Medicare Part B Discarded Drug Units database, we analyzed reimbursement data for discarded antineoplastic and hematology therapies from 2017 to 2020.

RESULTS

Medicare Part B utilization data was extracted for 77 therapies. From 2017 to 2020, the median annual dollar value of discarded therapies was $590 million. Every year, bortezomib, azacitidine, cabazitaxel, and decitabine were among the most wasted products, an average 24% waste. The IIJA policy would have impacted a median of 20 oncology agents and resulted in median annual refund of $172 million. Had the top five most discarded therapies been redistributed, they could have treated 18,289 patients. The five most wasted drugs were all dosed by weight and distributed in single-use vials.

CONCLUSION

The IIJA could potentially significantly reduce waste or encourage redistribution to treat thousands of additional patients. We propose that a fusion of fixed and weight-based dosing may help reduce wasteful medication administration by offering doses that better accommodate most patients. We anticipate that manufacturers will adapt to the IIJA perhaps by adjusting fixed doses or simply increasing drug prices. If price changes from dose delivery adjustment occur, rebates offered to pharmacy benefit managers and insurers will likely follow suit and may alter formulary positioning.

Predicting Colloidal Stability of High-Concentration Monoclonal Antibody Formulations in Common Pharmaceutical Buffers Using Improved Polyethylene Glycol Induced Protein Precipitation Assay

Colloidal stability is an important consideration when developing high concentration mAb formulations. PEG-induced protein precipitation is a commonly used assay to assess the colloidal stability of protein solutions. However, the practical usefulness and the current theoretical model for this assay have yet to be verified over a large formulation space across multiple mAbs and mAb-based modalities. In the present study, we used PEG-induced protein precipitation assays to evaluate colloidal stability of 3 mAbs in 24 common formulation buffers at 20 and 5 °C. These prediction assays were conducted at low protein concentration (1 mg/mL). We also directly characterized high concentration (100 mg/mL) formulations for cold-induced phase separation, turbidity, and concentratibility by ultrafiltration. This systematic study allowed analysis of the correlation between the results of low concentration assays and the high concentration attributes. The key findings of this study include the following: (1) verification of the usefulness of three different parameters (Cmid, μB, and Tcloud) from PEG-induced protein precipitation assays for ranking colloidal stability of high concentration mAb formulations; (2) a new method to implement PEG-induced protein precipitation assay suitable for high throughput screening with low sample consumption; (3) improvement in the theoretical model for calculating robust thermodynamic parameters of colloidal stability (μB and εB) that are independent of specific experimental settings; (4) systematic evaluation of the effects of pH and buffer salts on colloidal stability of mAbs in common formulation buffers. These findings provide improved theoretical and practical tools for assessing the colloidal stability of mAbs and mAb-based modalities during formulation development.

Effect of Obesity on the Pharmacokinetics and Pharmacodynamics of Anticancer Agents

An objective of the Precision Medicine Initiative, launched in 2015 by the US Food and Drug Administration and National Institutes of Health, is to optimize and individualize dosing of drugs, especially anticancer agents, with high pharmacokinetic and pharmacodynamic variability. The American Society of Clinical Oncology recently reported that 40% of obese patients receive insufficient chemotherapy doses and exposures, which may lead to reduced efficacy, and recommended pharmacokinetic studies to guide appropriate dosing in these patients. These issues will only increase in importance as the incidence of obesity in the population increases. This publication reviews the effects of obesity on (1) tumor biology, development of cancer, and antitumor response; (2) pharmacokinetics and pharmacodynamics of small-molecule anticancer drugs; and (3) pharmacokinetics and pharmacodynamics of complex anticancer drugs, such as carrier-mediated agents and biologics. These topics are not only important from a scientific research perspective but also from a drug development and regulator perspective. Thus, it is important to evaluate the effects of obesity on the pharmacokinetics and pharmacodynamics of anticancer agents in all categories of body habitus and especially in patients who are obese and morbidly obese. As the effects of obesity on the pharmacokinetics and pharmacodynamics of anticancer agents may be highly variable across drug types, the optimal dosing metric and algorithm for difference classes of drugs may be widely different. Thus, studies are needed to evaluate current and novel metrics and methods for measuring body habitus as related to optimizing the dose and reducing pharmacokinetic and pharmacodynamic variability of anticancer agents in patients who are obese and morbidly obese.

Product safety aspects of plant molecular farming

Plant molecular farming (PMF) has been promoted since the 1990s as a rapid, cost-effective and (most of all) safe alternative to the cultivation of bacteria or animal cells for the production of biopharmaceutical proteins. Numerous plant species have been investigated for the production of a broad range of protein-based drug candidates. The inherent safety of these products is frequently highlighted as an advantage of PMF because plant viruses do not replicate in humans and vice versa. However, a more nuanced analysis of this principle is required when considering other pathogens because toxic compounds pose a risk even in the absence of replication. Similarly, it is necessary to assess the risks associated with the host system (e.g., the presence of toxic secondary metabolites) and the production approach (e.g., transient expression based on bacterial infiltration substantially increases the endotoxin load). This review considers the most relevant host systems in terms of their toxicity profile, including the presence of secondary metabolites, and the risks arising from the persistence of these substances after downstream processing and product purification. Similarly, we discuss a range of plant pathogens and disease vectors that can influence product safety, for example, due to the release of toxins. The ability of downstream unit operations to remove contaminants and process-related toxic impurities such as endotoxins is also addressed. This overview of plant-based production, focusing on product safety aspects, provides recommendations that will allow stakeholders to choose the most appropriate strategies for process development.

Drug delivery breakthrough technologies - A perspective on clinical and societal impact

The way a drug molecule is administered has always had a profound impact on people requiring medical interventions - from vaccine development to cancer therapeutics. In the Controlled Release Society Fall Symposium 2022, a trans-institutional group of scientists from industry, academia, and non-governmental organizations discussed what a breakthrough in the field of drug delivery constitutes. On the basis of these discussions, we classified drug delivery breakthrough technologies into three categories. In category 1, drug delivery systems enable treatment for new molecular entities per se, for instance by overcoming biological barriers. In category 2, drug delivery systems optimize efficacy and/or safety of an existing drug, for instance by directing distribution to their target tissue, by replacing toxic excipients, or by changing the dosing reqimen. In category 3, drug delivery systems improve global access by fostering use in low-resource settings, for instance by facilitating drug administration outside of a controlled health care institutional setting. We recognize that certain breakthroughs can be classified in more than one category. It was concluded that in order to create a true breakthrough technology, multidisciplinary collaboration is mandated to move from pure technical inventions to true innovations addressing key current and emerging unmet health care needs.

Contemporary Monoclonal Antibody Utilization in Glomerular Diseases

Therapeutic monoclonal antibodies (MAbs) have been one of the fastest growing drug classes in the past 2 decades and are indicated in the treatment of cancer, autoimmune disorders, solid organ transplantation, and glomerular diseases. The Food and Drug Administration has approved 100 MAbs between 1986 and 2021, and MAbs account for 20% of Food and Drug Administration's new drug approval every year. MAbs are preferred over traditional immunosuppressive agents because of their high specificity, reduced number of drug-drug interactions, and low toxicity, which make them a prime example of personalized medicine. In this review article, we provide an overview of the taxonomy, pharmacology, and therapeutic applications of MAbs in glomerular diseases. We searched the literature through PubMed using the following search terms: monoclonal antibodies, glomerular diseases, pharmacokinetics, pharmacodynamics, immunoglobulin, murine, chimeric,humanized, and fully human, and limited our search to years 2018-2023. We selected peer-reviewed journal articles with an evidence-based approach, prioritizing randomized control trials in specific glomerular diseases, if available. Advances in the MAb field have resulted in a significant paradigm shift in targeted treatment of immune-mediated glomerular diseases, and multiple randomized control trials are currently being conducted. Increased recognition is critical to expand their use in experimental research and personalized medicine.

Pharmacokinetic serum concentrations of VRC01 correlate with prevention of HIV-1 acquisition

BACKGROUND

The phase 2b proof-of-concept Antibody Mediated Prevention (AMP) trials showed that VRC01, an anti-HIV-1 broadly neutralising antibody (bnAb), prevented acquisition of HIV-1 sensitive to VRC01. To inform future study design and dosing regimen selection of candidate bnAbs, we investigated the association of VRC01 serum concentration with HIV-1 acquisition using AMP trial data.

METHODS

The case-control sample included 107 VRC01 recipients who acquired HIV-1 and 82 VRC01 recipients who remained without HIV-1 during the study. We measured VRC01 serum concentrations with a qualified pharmacokinetic (PK) Binding Antibody Multiplex Assay. We employed nonlinear mixed effects PK modelling to estimate daily-grid VRC01 concentrations. Cox regression models were used to assess the association of VRC01 concentration at exposure and baseline body weight, with the hazard of HIV-1 acquisition and prevention efficacy as a function of VRC01 concentration. We also compared fixed dosing vs. body weight-based dosing via simulations.

FINDINGS

Estimated VRC01 concentrations in VRC01 recipients without HIV-1 were higher than those in VRC01 recipients who acquired HIV-1. Body weight was inversely associated with HIV-1 acquisition among both placebo and VRC01 recipients but did not modify the prevention efficacy of VRC01. VRC01 concentration was inversely correlated with HIV-1 acquisition, and positively correlated with prevention efficacy of VRC01. Simulation studies suggest that fixed dosing may be comparable to weight-based dosing in overall predicted prevention efficacy.

INTERPRETATION

These findings suggest that bnAb serum concentration may be a useful marker for dosing regimen selection, and operationally efficient fixed dosing regimens could be considered for future trials of HIV-1 bnAbs.

FUNDING

Was provided by the National Institutes of Health, National Institute of Allergy and Infectious Diseases (NIAID) (UM1 AI068614, to the HIV Vaccine Trials Network [HVTN]; UM1 AI068635, to the HVTN Statistical Data and Management Center [SDMC], Fred Hutchinson Cancer Center [FHCC]; 2R37 054165 to the FHCC; UM1 AI068618, to HVTN Laboratory Center, FHCC; UM1 AI068619, to the HPTN Leadership and Operations Center; UM1 AI068613, to the HIV Prevention Trials Network [HPTN] Laboratory Center; UM1 AI068617, to the HPTN SDMC; and P30 AI027757, to the Center for AIDS Research, Duke University (AI P30 AI064518) and University of Washington (P30 AI027757) Centers for AIDS Research; R37AI054165 from NIAID to the FHCC; and OPP1032144 CA-VIMC Bill & Melinda Gates Foundation.

A self-binding immune complex vaccine elicits strong neutralizing responses against herpes simplex virus in mice

Introduction

It has been known for over half a century that mixing an antigen with its cognate antibody in an immune complex (IC) can enhance antigen immunogenicity. However, many ICs produce inconsistent immune responses, and the use of ICs in the development new vaccines has been limited despite the otherwise widespread success of antibody-based therapeutics. To address this problem, we designed a self-binding recombinant immune complex (RIC) vaccine which mimics the larger ICs generated during natural infection.

Materials and methods

In this study, we created two novel vaccine candidates: 1) a traditional IC targeting herpes simplex virus 2 (HSV-2) by mixing glycoprotein D (gD) with a neutralizing antibody (gD-IC); and 2) an RIC consisting of gD fused to an immunoglobulin heavy chain and then tagged with its own binding site, allowing self-binding (gD-RIC). We characterized the complex size and immune receptor binding characteristics in vitro for each preparation. Then, the in vivo immunogenicity and virus neutralization of each vaccine were compared in mice.

Results

gD-RIC formed larger complexes which enhanced C1q receptor binding 25-fold compared to gD-IC. After immunization of mice, gD-RIC elicited up to 1,000-fold higher gD-specific antibody titers compared to traditional IC, reaching endpoint titers of 1:500,000 after two doses without adjuvant. The RIC construct also elicited stronger virus-specific neutralization against HSV-2, as well as stronger cross-neutralization against HSV-1, although the proportion of neutralizing antibodies to total antibodies was somewhat reduced in the RIC group.

Discussion

This work demonstrates that the RIC system overcomes many of the pitfalls of traditional IC, providing potent immune responses against HSV-2 gD. Based on these findings, further improvements to the RIC system are discussed. RIC have now been shown to be capable of inducing potent immune responses to a variety of viral antigens, underscoring their broad potential as a vaccine platform.

The Challenges of Treating Patients with Breast Cancer and Obesity

Obesity is defined as a body mass index (BMI) of 30 kg/m2 or more and is associated with worse outcomes in patients with breast cancer, resulting in an increased incidence of breast cancer, recurrence, and death. The incidence of obesity is increasing, with almost half of all individuals in the United States classified as obese. Patients with obesity present with unique pharmacokinetics and physiology and are at increased risk of developing diabetes mellitus and cardiovascular disease, which leads to specific challenges when treating these patients. The aim of this review is to summarize the impact of obesity on the efficacy and toxicity of systemic therapies used for breast cancer patients, describe the molecular mechanisms through which obesity can affect systemic therapies, outline the existing American Society of Clinical Oncology (ASCO) guidelines for treating patients with cancer and obesity, and highlight additional clinical considerations for treating patients with obesity and breast cancer. We conclude that further research on the biological mechanisms underlying the obesity-breast cancer link may offer new treatment strategies, and clinicals trials that focus on the treatment and outcomes of patients with obesity and all stages of breast cancer are needed to inform future treatment guidelines.

A Systematic Evaluation of Cost-Saving Dosing Regimens for Therapeutic Antibodies and Antibody-Drug Conjugates for the Treatment of Lung Cancer

BACKGROUND

Expensive novel anticancer drugs put a serious strain on healthcare budgets, and the associated drug expenses limit access to life-saving treatments worldwide.

OBJECTIVE

We aimed to develop alternative dosing regimens to reduce drug expenses.

METHODS

We developed alternative dosing regimens for the following monoclonal antibodies used for the treatment of lung cancer: amivantamab, atezolizumab, bevacizumab, durvalumab, ipilimumab, nivolumab, pembrolizumab, and ramucirumab; and for the antibody-drug conjugate trastuzumab deruxtecan. The alternative dosing regimens were developed by means of modeling and simulation based on the population pharmacokinetic models developed by the license holders. They were based on weight bands and the administration of complete vials to limit drug wastage. The resulting dosing regimens were developed to comply with criteria used by regulatory authorities for in silico dose development.

RESULTS

We found that alternative dosing regimens could result in cost savings that range from 11 to 28%, and lead to equivalent pharmacokinetic exposure with no relevant increases in variability in exposure.

CONCLUSIONS

Dosing regimens based on weight bands and the use of complete vials to reduce drug wastage result in less expenses while maintaining equivalent exposure. The level of evidence of our proposal is the same as accepted by regulatory authorities for the approval of alternative dosing regimens of other monoclonal antibodies in oncology. The proposed alternative dosing regimens can, therefore, be directly implemented in clinical practice.

Holistic View on the Structure of Immune Response: Petri Net Model

The simulation of immune response is a challenging task because quantitative data are scarce. Quantitative theoretical models either focus on specific cell-cell interactions or have to make assumptions about parameters. The broad variation of, e.g., the dimensions and abundance between lymph nodes as well as between individual patients hampers conclusive quantitative modeling. No theoretical model has been established representing a consensus on the set of major cellular processes involved in the immune response. In this paper, we apply the Petri net formalism to construct a semi-quantitative mathematical model of the lymph nodes. The model covers the major cellular processes of immune response and fulfills the formal requirements of Petri net models. The intention is to develop a model taking into account the viewpoints of experienced pathologists and computer scientists in the field of systems biology. In order to verify formal requirements, we discuss invariant properties and apply the asynchronous firing rule of a place/transition net. Twenty-five transition invariants cover the model, and each is assigned to a functional mode of the immune response. In simulations, the Petri net model describes the dynamic modes of the immune response, its adaption to antigens, and its loss of memory.

Customer-centric product presentations for monoclonal antibodies

Delivering customer-centric product presentations for biotherapeutics, such as monoclonal antibodies (mAbs), represents a long-standing and paramount area of engagement for pharmaceutical scientists. Activities include improving experience with the dosing procedure, reducing drug administration-related expenditures, and ultimately shifting parenteral treatments outside of a controlled healthcare institutional setting. In times of increasingly cost-constrained markets and reinforced with the coronavirus pandemic, this discipline of "Product Optimization" in healthcare has gained momentum and changed from a nice-to-have into a must. This review summarizes latest trends in the healthcare ecosystem that inform key strategies for developing customer-centric products, including the availability of a wider array of sustainable drug delivery options and treatment management plans that support dosing in a flexible care setting. Three disease area archetypes with varying degree of implementation of customer-centric concepts are introduced to highlight relevant market differences and similarities. Namely, rheumatoid arthritis and inflammatory bowel disease, multiple sclerosis, and oncology have been chosen due to differences in the availability of subcutaneously dosed and ready-to-use self-administration products for mAb medicines and their follow-on biologics. Different launch scenarios are described from a manufacturer's perspective highlighting the necessity of platform approaches. To unfold the full potential of customer-centric care, value-based healthcare provider reimbursement schemes that incentivize the efficiency of care need to be broadly implemented.

Flat dose regimen of toripalimab based on model-informed drug development approach

Introduction: Flat dosing regimen has recently been approved for programmed death receptor-1 (PD-1) inhibitors including toripalimab, nivolumab and pembrolizumab. The objective of this study is to provide pharmacological evidence for a flat dosing regimen of toripalimab by assessing the efficacy and safety profile of a 240 mg Q3W flat dose relative to the currently approved 3 mg/kg Q2W. Methods: A population pharmacokinetic (PopPK) model was established based on 1,014 evaluable patients in 13 clinical studies. The exposure-objective response rate (ORR, n = 234) and exposure-safety (n = 152) analyses were performed by logistic regression. Three safety endpoints including grade ≥ 3 adverse events (AEs), treatment-related grade ≥ 3 AEs, and AEs leading to study drug discontinuation were evaluated. Progression-free survival (PFS, n = 234) was evaluated using a Cox proportional hazard model with the Kaplan-Meier survival curve. Results: The PK profiles of toripalimab are best described by a two-compartment model with time-varying clearance characterized by a sigmoidal maximum effect (E_max) function. Simulations for the first dose and steady-state exposures for the 240 mg Q3W dosing regimen were comparable to those for the 3 mg/kg Q2W dosing regimen with 95% exposure coverage ranging from 88% to 96%. The exposure-safety analysis showed that the probability of an adverse event occurring did not increase with increases in toripalimab exposure. A flat exposure-response relationship for ORR was identified. The Kaplan-Meier survival curve showed that exposure was a predictor for PFS; however, no difference in treatment benefit was demonstrated across exposure quantiles using a Cox proportional hazard model. Discussion: This study revealed that toripalimab exposure of 240 mg Q3W dosing regimen was comparable to 3 mg/kg Q2W dosing regimen. The safety and efficacy E-R results of 240 mg Q3W is flat. Hence, the 240 mg Q3W dosing regimen is determined to be a preferred therapeutic dosage for toripalimab due to the convenience of flat dose.

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.

Chemotherapy and Anticancer Drugs Adjustment in Obesity: A Narrative Review

BACKGROUND

Obese individuals have higher rates of cancer incidence and cancer- related mortality. The worse chemotherapy outcomes observed in this subset of patients are multifactorial, including the altered physiology in obesity and its impact on pharmacokinetics, the possible increased risk of underdosing, and treatment-related toxicity.

AIMS

The present review aimed to discuss recent data on physiology, providing just an overall perspective and pharmacokinetic alterations in obesity concerning chemotherapy. We also reviewed the controversies of dosing adjustment strategies in adult and pediatric patients, mainly addressing the use of actual total body weight and ideal body weight.

METHODS

This narrative review tried to provide the best evidence to support antineoplastic drug dosing strategies in children, adolescents, and adults.

RESULTS

Cardiovascular, hepatic, and renal alterations of obesity can affect the distribution, metabolism, and clearance of drugs. Anticancer drugs have a narrow therapeutic range, and variations in dosing may result in either toxicity or underdosing. Obese patients are underrepresented in clinical trials that focus on determining recommendations for chemotherapy dosing and administration in clinical practice. After considering associated comorbidities, the guidelines recommend that chemotherapy should be dosed according to body surface area (BSA) calculated with actual total body weight, not an estimate or ideal weight, especially when the intention of therapy is the cure.

CONCLUSION

The actual total body weight dosing appears to be a better approach to dosing anticancer drugs in both adults and children when aiming for curative results, showing no difference in toxicity and no limitation in treatment outcomes compared to adjusted doses.

Association of Body Mass Index With the Safety Profile of Nivolumab With or Without Ipilimumab

Importance

Increased survival with immune checkpoint inhibitors has been reported for patients with obesity vs a normal body mass index (BMI). However, the association of obesity with the safety of immune checkpoint inhibitors warrants study.

Objective

To investigate associations between BMI and immune-related adverse events (irAEs) among patients with advanced cancers treated with nivolumab monotherapy and nivolumab plus ipilimumab combination therapy.

Design, Setting, and Participants

This study was a retrospective pooled analysis of 3772 patients from 14 multicenter CheckMate clinical trials across 8 tumor types. Patients with advanced cancers received nivolumab, 3 mg/kg (n = 2746); nivolumab, 3 mg/kg, plus ipilimumab, 1 mg/kg (n = 713); or nivolumab, 1 mg/kg, plus ipilimumab, 3 mg/kg (n = 313). Baseline BMI was categorized as normal weight or underweight (<25), overweight (25 to <30), or obese (≥30) according to World Health Organization criteria. The studies began patient enrollment between February 9, 2012, and May 21, 2015, and patients were followed up to database lock on May 1, 2019. Data analysis was conducted from May 1 to September 1, 2019.

Interventions

Nivolumab, 3 mg/kg; nivolumab, 3 mg/kg, plus ipilimumab, 1 mg/kg; and nivolumab, 1 mg/kg, plus ipilimumab, 3 mg/kg.

Main Outcomes and Measures

Odds ratios (ORs) and 95% CIs for incidence of any-grade and grade 3 or 4 irAEs were calculated for patients with obesity vs normal weight or underweight BMI in the overall cohort and in subgroups based on patient and tumor characteristics. Analyses for nivolumab plus ipilimumab cohorts were exploratory.

Results

A total of 3772 patients were included, 2600 were male (69%), and median age was 61 years (range, 18-90 years). For patients receiving monotherapy with nivolumab, 3 mg/kg (n = 2746), the incidence of any-grade irAEs was higher in patients with obesity (n = 543) vs those with normal weight or underweight BMI (n = 1266; OR, 1.71; 95% CI, 1.38-2.11). Incidence of grade 3 or 4 irAEs did not differ between patients with obesity and those with normal weight or underweight BMI (OR, 1.21; 95% CI, 0.92-1.61). Risk of any-grade and grade 3 or 4 irAEs appeared consistent with that in the overall population across all subgroups evaluated except for a higher likelihood of grade 3 or 4 irAEs among female patients with obesity vs normal weight or underweight BMI (OR, 1.73; 95% CI, 1.07-2.79). For patients receiving nivolumab plus ipilimumab, the incidence of irAEs appeared consistent across BMI categories.

Conclusions and Relevance

Obesity appeared to be associated with an increased incidence of any-grade irAEs among patients treated with nivolumab monotherapy and with grade 3 or 4 irAEs among female patients only. These findings may inform the monitoring of patients at high risk of developing irAEs.

Development of Therapeutic Proteins for a New Subcutaneous Route of Administration after the Establishment of Intravenous Dosages: A Systematic Review

Therapeutic proteins may first be developed as intravenous (i.v.) therapies with new subcutaneous (s.c.) dosage forms being subsequently developed to provide an alternative route of administration. As of August 2022, there have been 9 therapeutic proteins which were developed as a new s.c. dosage form after the approval of the corresponding i.v. product. This article provides a systematic review of prior experiences in the i.v. to s.c. switch development programs. We describe what types of clinical studies were conducted to support the i.v. to s.c. switch for these nine therapeutic proteins. Publicly available scientific advice from health authorities is summarized, particularly regarding recommendations on overall development strategy, dose selection, immunogenicity assessment, and indication extrapolation. The clinical data from these i.v. to s.c. development programs demonstrate that: (1) when switching from i.v. dosing to s.c. dosing, trough drug concentration (C_trough ) from s.c. dosing should not be inferior to i.v. dosing with average drug concentration (C_avg ; equivalent to AUC, area under the curve after correcting for dosing intervals between i.v. and s.c. administration) being matched or non-inferior to i.v. dosing; and (2) with appropriate s.c. dose regimens, treatment with s.c. therapeutic proteins can generally achieve similar efficacy and safety as the corresponding i.v. products, suggesting that the much higher maximum concentration (C_max ) after i.v. infusion as compared with that from s.c. injection is often not relevant to the treatment effect.

Combined Vaccination with B Cell Peptides Targeting Her-2/neu and Immune Checkpoints as Emerging Treatment Option in Cancer

The application of monoclonal antibodies (mAbs), targeting tumor-associated (TAAs) or tumor-specific antigens or immune checkpoints (ICs), has shown tremendous success in cancer therapy. However, the application of mAbs suffers from a series of limitations, including the necessity of frequent administration, the limited duration of clinical response and the emergence of frequently pronounced immune-related adverse events. However, the introduction of mAbs has also resulted in a multitude of novel developments for the treatment of cancers, including vaccinations against various tumor cell-associated epitopes. Here, we reviewed recent clinical trials involving combination therapies with mAbs targeting the PD-1/PD-L1 axis and Her-2/neu, which was chosen as a paradigm for a clinically highly relevant TAA. Our recent findings from murine immunizations against the PD-1 pathway and Her-2/neu with peptides representing the mimotopes/B cell peptides of therapeutic antibodies targeting these molecules are an important focus of the present review. Moreover, concerns regarding the safety of vaccination approaches targeting PD-1, in the context of the continuing immune response, as a result of induced immunological memory, are also addressed. Hence, we describe a new frontier of cancer treatment by active immunization using combined mimotopes/B cell peptides aimed at various targets relevant to cancer biology.

Trends in Obesity Prevalence Among Patients Enrolled in Clinical Trials for Obesity-Related Cancers, 1986 to 2016

IMPORTANCE

Obesity rates have risen in the United States since the 1980s. Several studies have shown links between obesity and the incidence of specific cancer types, but none have systematically examined obesity prevalence at the time of cancer diagnosis, or among clinical trial participants, all of which may affect clinical outcomes.

OBJECTIVE

To examine the prevalence of obesity and, separately, overweight and obesity over 30 years among patients with cancer enrolled in clinical treatment trials for obesity-related cancers; and to compare trends with corresponding trends in the US.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study examined clinical treatment trials for obesity-related cancers conducted by the SWOG Cancer Research Network at community and academic sites. Participants included adult patients enrolled in phase 2 or phase 3 clinical treatment trials in obesity-related cancers between 1986 and 2016. Statistical analysis was performed from June 2020 to July 2022.

EXPOSURES

Year of enrollment to a clinical trial.

MAIN OUTCOMES AND MEASURES

Prevalence of obesity (body mass index [BMI] ≥ 30) and overweight or obesity (BMI > 25) at the time of clinical trial enrollment. Multivariable logistic regression analysis, adjusted for demographic and clinical factors, was used to analyze patient height and weight collected at clinical trial enrollment.

RESULTS

Among 23 926 patients (median [IQR] age, 58 [51-66] years; 17 594 [73.5%] female; 969 [4.0%] Hispanic, 2173 [9.1%] non-Hispanic Black, 19 890 [83.1%] non-Hispanic White) enrolled between 1986 and 2016, unadjusted obesity rates increased from 23.5% (in 1986 to 1990 [n = 657]) to 42.3% (in 2011 to 2016 [n = 836]). There was an increasing linear trend in obesity (odds ratio [OR], 1.23 for each 5-year increase; 95% CI, 1.21-1.26; P < .001), which persisted after covariate adjustment for demographic and clinical characteristics. Findings were consistent for the combined prevalence of overweight and obesity. The observed overall increasing trend in obesity prevalence from 1999-2000 to 2015-2016 was greater in trial patients (21.3% [SE = 0.7] to 49.1% [SE = 1.6]) than in US adults (30.5% [SE = 1.5] to 39.6% [SE = 1.6]) (P for trend = .03), but was similar to US cancer survivors (18.9% [SE = 1.9] to 42.2% [SE = 2.1]; P for trend = .31).

CONCLUSIONS AND RELEVANCE

This cohort study found that patients with cancer and obesity are currently well-represented in cancer clinical trials, increasing confidence that trial findings are generalizable to patients with obesity in clinical practice. Availability of data on height and weight at diagnosis through cancer registries will enable a more rigorous analysis of obesity prevalence among patients with cancer.

Dose modification rules and availability of growth factor support: A cross-sectional study of head-to-head cancer trials used for US FDA approval from 2009 to 2021

AIM OF THE STUDY

Different drug modification rules or growth factor support guidance may affect the results in oncology randomised controlled trials. We aimed to estimate the prevalence of unequal rules for dose modification rules or the use of myeloid growth factors in head-to-head registration Food and Drug Administration trials.

METHODS

This cross-sectional analysis included all head-to-head registration randomised controlled trials leading to a US Food and Drug Administration approval between 2009 and 2021. Trials examined anti-cancer drugs in the advanced or metastatic setting where a comparison could be made between arms regarding either dose modification rules or myeloid growth factors recommendations. Sixty-two registration trials met inclusion criteria. Information abstracted for each trial included tumour type, setting, phase, and type of sponsor. We assessed, according to pre-specified rules, imbalance in drug modification rules, myeloid growth factors recommendations or both.

RESULTS

We find 40 of 62 (65%) selected trials have unequal rules for dose medication, granulocyte colony-stimulating factor (G-CSF) use or both. Six trials (10%) had rules favouring the control arm, while 55% of selected trials (34/62) favoured the experimental arm. Among these, 50% (17/34) had unequal drug modification rules, 41% (14/34) had unequal G-CSF rules and 9% contained both (3/34).

CONCLUSION

We find that 55% of trials testing anti-cancer drugs against each other used protocol rules that favoured the experimental arm. This leaves open the question of whether new molecules are truly superior to older molecules or if instead different outcomes are due to more aggressive dosing or growth factor support. Trials should utilise equal rules for dose medication and G-CSF support.

Active immunization with a Her-2/neu-targeting Multi-peptide B cell vaccine prevents lung metastases formation from Her-2/neu breast cancer in a mouse model

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Trastuzumab and Pertuzumab extend the overall survival of breast cancer patients.

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Unlike monoclonal antibodies B cell peptides induce immunological memory.

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A multi-peptide B cell-based vaccination prevents Her-2/neu lung metastasis in mice.

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The vaccination results in Her-2/neu-negative tumors, with increased PD-L1 expression.

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A combination/alternating therapy for a total remission of metastases is suggested.

In pre-clinical and clinical settings, active immunization with a Her-2/neu vaccine (HerVaxx), comprising B-cell peptide from Trastuzumab binding site, has been shown to reduce primary tumor growth via induction of polyclonal anti-tumor immune responses and immunological memory. Here, we tested the combination of HerVaxx and the recently identified B-cell epitope/mimotope of Pertuzumab, i.e. a multi-peptide B-cell vaccine, for preventing Her-2/neu lung metastases formation in a mouse model. Active immunization with the multi-peptide vaccine was associated with decreased lung weights, and histological evaluation of the lungs showed that the significant reduction of lung metastases was associated with increased CD4⁺ and CD8⁺ T cell infiltration. Notably, along with the overall reduction of lungs weights and Her-2 positive metastases, a formation of Her-2/neu-negative tumors but with increased PD-L1 expression was observed. Our results might pave the way to a multi-peptide B-cell Her-2/neu vaccine serving as a secondary intervention in adjuvant settings to prevent tumor recurrence and spread. Moreover, combination therapy targeting PD-L1 may result in total remission of metastases. Such a therapy may be used clinically to alternately target Her-2/neu and PD-L1 in metastatic breast cancer.

The Coming of Age of Biosimilars: A Personal Perspective

Biosimilars have come of age over the past 17 years, with 84 approvals in the EU and 35 in the US, representing almost 90% of the world market. While the acceptance of biosimilars in the US is catching up with that in the EU, the cost benefits remain elusive due to the high development barrier and complex distribution system involved, mainly in the US. In the EU, the cost of biosimilars has already dropped 70% or more, and interchangeability is a routine in some European jurisdictions, unlike in the US, where a separate regulatory approval is required. This paper projects significant changes coming in the US and EU’s biosimilars approval requirements that will impact the approval procedures in the rest of the world, leading to dramatic changes in the cost of biosimilars to patients. This perspective is based on the author’s first-hand experience to secure FDA approvals of biosimilars and an extensive analysis of the rationality of testing to demonstrate biosimilarity. Multiple citizen petitions by the author and meetings with the FDA may have prompted the recent announcement by the FDA to award a $5 million research grant to scientists to develop novel testing models to establish biosimilarity, including modifying the interchangeability protocols. Soon, demonstration of biosimilarity will not require animal testing and, in most cases, clinical efficacy testing; over time, the clinical pharmacology testing will be reduced as the regulatory agencies develop more confidence in the safety and efficacy of biosimilars. Biosimilars have come of age; now it is the turn of the developers to grow up, and one way to show this is to challenge the current regulatory guidelines but only on scientific grounds to seek more concessions, for which both FDA and EMA are ready.