Model-Based Population Pharmacokinetic Analysis of Nivolumab in Patients With Solid Tumors

A Systematic Evaluation of the Dosing Regimens for Approved Targeted Therapies and Immune Checkpoint Inhibitors in Metastatic Renal Cell Carcinoma From a Project OPTIMUS Perspective

Targeted therapies and immune checkpoint inhibitors (ICIs) have significantly improved survival outcomes in metastatic renal cell carcinoma (mRCC) but are often associated with high rates of adverse events, leading to dose reductions or treatment discontinuation. The FDA's recent initiative, Project OPTIMUS, emphasizes the importance of optimizing dosing regimens in oncology clinical development, and moves beyond the conventional maximum tolerated dose approach. In this study, we aimed to review and redefine the approved dosing strategies for targeted therapies and ICIs in mRCC from the Project OPTIMUS perspective, including pazopanib, axitinib, cabozantinib, sunitinib, everolimus, and nivolumab. A comprehensive summary of FDA clinical pharmacology reviews and clinical studies performed in routine clinical practice was conducted, alongside model-informed simulations of pharmacokinetic profiles with approved and alternative regimens. Results demonstrated that actual tolerated doses in clinical practice were 46.1% to 86% lower than the approved dosages, with up to 75% of patients requiring dose adjustments. Model-informed simulations suggested that for most targeted therapies, a 14%-50% dose reduction maintained comparable efficacy while improving tolerability. For nivolumab, simulations confirmed adequate drug exposure with the approved flat dose regimens, without an increase of adverse effects. In conclusion, we identified optimized dosing regimens that could improve drug tolerability while maintaining efficacy for approved targeted therapies and ICIs in mRCC. We suggest that these optimized dosing regimens should be considered for use in clinical practice and that the optimal exposure range be included in drug labels to support pharmacokinetically guided dose individualization in clinical practice.

Model-Informed Immunogenicity Assessment of Nivolumab as Monotherapy and in Combination with Ipilimumab

Immunogenicity to biotherapeutics can lead to antidrug antibodies (ADAs) that have potential to alter pharmacokinetics (PK), efficacy, and safety. Here we provide an extensive model-informed immunogenicity assessments of nivolumab monotherapy and in combination with ipilimumab across multiple clinical trials. ADA was evaluated as both a binary and semiquantitative covariate, incorporating ADA titers to account for intensity over time. Data from 28 clinical trials, including 7,820 subjects with 2,770 ADA titer measurements, were analyzed using population pharmacokinetic (popPK) modeling. Nivolumab ADA incidence rate was higher for combination therapy (~ 32%) compared to monotherapy (~ 16%). ADA increased nivolumab clearance (CL) by 20-80% depending on titer. Nivolumab ADA impact on efficacy and safety was evaluated in melanoma and non-small cell lung cancer (NSCLC) patients. Despite the occurrence of nivolumab ADA being associated with lower nivolumab exposures, objective response rates (ORR) were similar in ADA-positive and negative patients, and ADA titer was not a significant predictor of response. An overall survival (OS) landmark analysis at 3 months suggested similar OS for NSCLC but lower OS for melanoma for ADA-positive vs negative patients mainly due to the imbalanced patient baseline characteristics. Propensity score matching and multivariable Cox Proportional-Hazards analysis indicated no ADA impact on OS. Additionally, there were no associations between ADA and acute hypersensitivities or immune mediated safety events. This model-based approach underscores the importance of accounting for ADA dynamics in clinical development and supports no significant association between ADA presence and clinical efficacy or safety, even with higher ADA incidence in combination therapy.

Remote presentation of nivolumab-induced bullous pemphigoid in hepatocellular carcinoma

A man in his 70s with a history of unresectable hepatocellular carcinoma (HCC) treated with nivolumab presented with a blistering rash 14 months after nivolumab initiation. Biopsies and direct immunofluorescence confirmed the diagnosis of bullous pemphigoid (BP). BP is an autoimmune skin disorder in which autoantibodies bind to the dermal-epidermal junction. It is a rare sequela of programmed cell death protein-1 (PD-1) inhibitors that can develop after treatment initiation and typically resolve soon after discontinuation. Most cases are reported in melanoma and non-small cell lung cancers, and rarely in HCC irrespective of the timing of onset. We describe a rare presentation of remote BP with PD-1 inhibitor use in HCC. PD-1 inhibitor-induced BP is a rare cutaneous immune-related adverse event, and this case highlights the variability in onset and chronicity.

Integrating International Consensus Guidelines for Anticancer Drug Dosing in Kidney Dysfunction (ADDIKD) into everyday practice

Part 2 of the International Consensus Guideline on Anticancer Drug Dosing in Kidney Dysfunction (ADDIKD) offers drug-specific consensus recommendations based on both evidence and practical experience. These recommendations build upon the kidney function assessment and classification guidelines established in Part 1 of ADDIKD. Here we illustrate how dosing recommendations differ between ADDIKD and existing guidance for four commonly used drugs: methotrexate, cisplatin, carboplatin and nivolumab. We then describe how the recommendations can be distilled into practice points for methotrexate and cisplatin. While ADDIKD is a significant improvement from previous guidelines, adoption of this new guideline requires further endorsement from key external stakeholders, 'change championing' by clinicians locally and encouraging its integration into existing reference sources, clinical trial protocols and electronic prescribing systems.

Funding

Development of the ADDIKD guideline is funded by the NSW Government as part of the Cancer Institute NSW and received no funding from external commercial sources.

From Prospective Evaluation to Practice: Model-Informed Dose Optimization in Oncology

One dose does not fit all, especially in oncolytic drugs, where side effects and therapy failures highlight the need for personalized dosing approaches. In recent years, the quest to apply model-informed precision dosing to oncology drugs has gained significant momentum, reflecting its potential to revolutionize patient care by tailoring treatments to individual pharmacokinetic profiles. Despite this progress, model-informed precision dosing has not (yet) become widely integrated into routine clinical care. We aimed to explain model-informed precision dosing from a clinical viewpoint while addressing all prospective model-informed precision dosing implementation and validation studies in the field of oncology. We identified 16 different drugs for which prospective model-informed precision dosing validation/implementation has been performed. Although these studies are mostly focused on attaining adequate drug exposures and reducing inter-individual variability, improved clinical outcomes after performing model-informed precision dosing were shown for busulfan, and high-dose methotrexate. Toxicities were significantly reduced for busulfan and cyclophosphamide treatment. In contrast, for carboplatin, for which model-informed precision dosing has been used in the Calvert formula, no prospective validation on outcomes was deemed necessary as the therapeutic window had been extensively validated. Model-informed precision dosing has shown to be of added value in oncology and is expected to significantly change dosing regimens in the future.

Safety and Efficacy of Copanlisib in Combination with Nivolumab: A Phase Ib Study in Patients with Advanced Solid Tumors

PURPOSE

Copanlisib in combination with immune checkpoint inhibitors demonstrated synergy and favorable antitumor immune responses in preclinical models. This study evaluated copanlisib plus nivolumab in adults with advanced solid tumors.

PATIENTS AND METHODS

In this phase Ib, nonrandomized, open-label, dose-escalation study, patients received intravenous nivolumab 240 mg (day 15 of cycle 1 and days 1 and 15 of subsequent cycles) plus intravenous copanlisib (45 or 60 mg on days 1, 8, and 15 of each cycle) in 28-day cycles. The primary objective was to determine the MTD and/or recommended phase II dose of copanlisib plus nivolumab. Secondary objectives were safety, tolerability, and efficacy. Exploratory objectives included evaluation of potentially predictive biomarkers.

RESULTS

Overall, 16 patients were treated [copanlisib: 45 mg (n = 5); 60 mg (n = 11)]. The most common cancer types at baseline were bladder (25.0%) and oropharyngeal (18.8%) cancers. No dose-limiting toxicities were observed; copanlisib 60 mg was deemed the recommended phase II dose in combination with nivolumab 240 mg. Grade 3 and 4 treatment-emergent adverse events were reported in 56.3% and 12.5% of patients, respectively; one grade 5 event was reported (unrelated to treatment). Overall, 18.8% of patients achieved a partial response. Evaluations of potential biomarkers did not correlate with response, but copanlisib-modulated biomarker changes were observed before nivolumab administration and were consistent and dose-dependent.

CONCLUSIONS

No new safety concerns were identified with this combination, and preliminary efficacy indicated an antitumor effect. Data supported an immunomodulatory effect of copanlisib, suggesting that this combination may enhance the efficacy of immune checkpoint inhibitors.

SIGNIFICANCE

The combination of copanlisib and nivolumab was well tolerated and showed antitumor effects in patients with advanced solid tumors. The number of circulating myeloid-derived suppressive cells decreased 24 to 48 hours after treatment with copanlisib. Further investigation of copanlisib and nivolumab is warranted as a novel strategy to enhance the efficacy of checkpoint inhibitors.

Liver Transplantation for Hepatocellular Carcinoma: An Expanding Cornerstone of Care in the Era of Immunotherapy

Liver transplantation (LT) has been accepted as a cornerstone of care in hepatocellular carcinoma (HCC) for almost three decades. In recent years, its role has been evolving to include patients with disease burden beyond the widely used Milan criteria. The integration of dynamic biomarkers such as alpha-fetoprotein together with downstaging approaches and tumor evolution after enlistment has allowed the selection of patients most likely to benefit, resulting in 5-year survival rates greater that 70%. With the increasing use of immune checkpoint inhibitors (ICIs) across all stages of disease, alone or in combination with locoregional therapies, there is now the potential to further expand the patient population with HCC who may benefit from LT. This brings challenges, given the global shortage of organs and the need to better understand the optimal use of ICIs before transplantation. Furthermore, the field of transplant oncology awaits additional biomarkers that can predict those likely to benefit from ICIs. More than ever, a multidisciplinary approach for liver cancer management is critical to ensure all patients are considered for LT where appropriate, and do not miss the opportunity for long-term survival.

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.

Nivolumab plasma concentration and clearance associated with overall survival in patients with renal cell carcinoma

BACKGROUND

Nivolumab is an immune checkpoint inhibitor (ICI) that selectively inhibits programmed cell death protein 1 activation, restoring antitumor immunity. ICIs are indicated for various types of advanced solid tumors; however, not all patients benefit from them, and tools that could be used in the clinic to predict response to treatment represent an unmet need. Here we describe the development of a new population pharmacokinetic (PPK) model in patients treated with nivolumab in clinical trials. Applying the model to a patient population with renal cell carcinoma identified nivolumab clearance and plasma concentration as predictors of overall survival (OS).

METHODS

A custom liquid chromatography with tandem mass spectrometry method for quantifying nivolumab plasma concentration was developed and validated following the European Medicines Agency guidelines for bioanalytical method validation. The PPK model was developed using data from patients treated in the NIVIPIT (n=38) and NIVOREN (n=137) trials of nivolumab in metastatic melanoma and renal cell carcinoma, respectively. The PPK model was used to determine pharmacokinetic (PK) parameters such as baseline clearance and simulate individual clearance changes over time. The relationship between PK characteristics (including clearance at Cycle 1 (CLC1), plasma concentration at Cycle 3 and clinical outcomes was assessed in 137 patients treated in NIVOREN. Kaplan-Meier methodology was used in time-to-event analyses.

RESULTS

In 137 patients, the median nivolumab CLC1 was 6 mL/hour and the median plasma concentration at Cycle 3 was 48 µg/mL. Median follow-up was 21.0 months (95% CI 20.2 to 22.5 months) with a survival rate at 6 months of 91.2% and 77.9% at 12 months. In univariate analysis, OS was significantly higher in patients with CLC1<6 mL/hour versus ≥6 mL/hour (HR 2.2 (95% CI 1.2 to 4.1), p=0.0146). Shorter OS was observed in patients with plasma concentration at Cycle 3 below the median (48 µg/mL) versus those above the median (HR 0.4 (95% CI 0.2 to 0.8), p=0.0069). Multivariate analysis showed a trend towards lower clearance, but this did not reach statistical significance (p=0.0694).

CONCLUSIONS

Results of the study may potentially be used to predict outcomes of nivolumab therapy in patients with renal cell carcinoma. Additional applications may include guiding dose adjustments of nivolumab in those who are less likely to respond to the initial dose.

Efficacy and Safety of Low-Dose Nivolumab in Treatment of Advanced Solid Tumors: A Retrospective Audit from Resource-Constrained Settings

Background

Immunotherapy has improved outcomes in many advanced solid tumors. In resource-constrained settings, less than 2% of patients can afford standard dose immunotherapy. A recent phase II study showed the efficacy of low-dose immunotherapy in this setting. We used low-dose immunotherapy on a compassionate basis in patients who had progressed on available standard treatment options and standard dose immunotherapy was not feasible.

Patients and Methods

We retrospectively collected data from the medical oncology department for consecutive patients who had initially received standard lines of therapy followed by low-dose immunotherapy (nivolumab 40 mg) on a compassionate basis. The demographic details, histology, prior treatment, clinical and radiological response, date of disease progression, date of death, and toxicity data were collected.

Results

A total of 54 consecutive patients, who received low-dose immunotherapy with nivolumab from January 1, 2018 to February 14, 2020, were included in this analysis; 4 patients were not radiologically evaluable. The median age was 50.4 years (range 35-74 years), male:female ratio was 6:1. The most common comorbidities were hypertension and diabetes seen in 12 (22.2%) and 6 (11.1%) patients, respectively. The majority of the patients (70.4%) were of head and neck cancer. The median follow-up was 4.5 months (range 0.5-11.7). Clinical benefit was observed in 18 (33.3%) patients. Partial response and stable disease were achieved in 9 (16.7%) and 5 (9.3%) patients, respectively. Median survival was not reached for these patients. Six months progression-free survival and overall survival were 100 versus 8.7% (hazard ratio [HR] 0.05, 95% confidence interval [CI]: 0.01-0.36; p  = 0.003) and 100 versus 29.7% (HR 0.03, 95% CI: 0.00-0.95; p  = 0.047), respectively, for responders and nonresponders. The side effects were manageable.

Conclusion

In resource-constrained settings, low-dose immunotherapy with nivolumab seems to be an effective treatment option. Further studies are warranted to evaluate this approach.

Subcutaneous versus intravenous nivolumab for renal cell carcinoma

BACKGROUND

The evolving oncology treatment paradigm has created an unmet need for administration options that improve patient experiences and health care efficiencies.

PATIENTS AND METHODS

CheckMate 67T (NCT04810078) was a phase III, open-label, multicenter, noninferiority trial in which patients with advanced/metastatic clear cell renal cell carcinoma were randomized to subcutaneous nivolumab (1200 mg every 4 weeks; coformulated with recombinant human hyaluronidase PH20 20 000 units) or intravenous nivolumab (3 mg/kg every 2 weeks). The primary objective was to assess the noninferiority of subcutaneous versus intravenous nivolumab by coprimary endpoints determined from a population pharmacokinetics analysis [time-averaged serum concentration over the first 28 days (Cavgd28), and minimum steady-state serum concentration (Cminss); noninferiority threshold: lower boundary of 90% confidence interval (CI) of the geometric mean ratios (GMR) ≥0.8]. Objective response rate (ORR) was a key secondary endpoint powered for noninferiority [noninferiority threshold: lower boundary of 95% CI of relative risk of ORR (subcutaneous versus intravenous nivolumab) ≥0.60].

RESULTS

Overall, 495 patients were randomized. Relative exposure in the subcutaneous versus intravenous arm reported by the GMR of Cavgd28 and Cminss was 2.098 (90% CI 2.001-2.200) and 1.774 (90% CI 1.633-1.927), respectively. After 8 months of minimum follow-up, ORR was 24.2% with subcutaneous nivolumab (95% CI 19.0%-30.0%) versus 18.2% with intravenous nivolumab [95% CI 13.6%-23.6%; relative risk: 1.33 (95% CI 0.94-1.87)]. Coprimary endpoints and ORR met noninferiority thresholds. Additional efficacy and safety measures were similar.

CONCLUSIONS

Subcutaneous nivolumab was noninferior to intravenous nivolumab based on pharmacokinetics and ORR. No new safety signals were observed.

Sex differences in the pharmacokinetics of anticancer drugs: a systematic review

BACKGROUND

In addition to the effect of body weight, a patient's sex can influence the pharmacokinetics (PK) of anticancer agents, and thereby their activity and safety. The magnitude and relevance of sex differences, however, are currently unclear.

METHODS

We carried out a systematic review of published studies (clinical, n ≥ 10) on Food and Drug Administration (FDA)-approved (on 31 January 2022) anticancer drugs (excluding hormonal agents), aiming to identify significant PK differences between male and female patients. A difference of ≥20% on PK parameters (clearance or trough concentration) was considered significant. The methodological quality was assessed using the National Institutes of Health study quality assessment tool. This systematic review was conducted according to the PRISMA2020 guidelines and a previously published protocol, which was registered in the PROSPERO database (number 291008).

RESULTS

Data on 99 anticancer agents (for a total of 1643 abstracts and European Medicines Agency/FDA documents) were screened. The final dataset included 112 articles and 8 European Medicines Agency/FDA documents. The median size of a study cohort was 445 patients (range: 12-6468 patients). Significant PK differences (>+20% in clearance or apparent clearance in women) were identified for 14 drugs, and potentially significant PK differences (due to conflicting reports) for another 8 drugs. None of the studies included sex-based summaries to assess whether the observed differences in PK may impact the efficacy or safety profile.

CONCLUSIONS

Significant sex differences in PK have been identified including commonly used drugs of different classes, such as 5-fluorouracil, doxorubicin, paclitaxel, regorafenib, atezolizumab, and temozolomide. The risk-benefit ratio for such anticancer drugs is likely to be improved by the development of sex-specific dosing strategies. Additional sex-based PK-pharmacodynamic analyses are recommended during dose optimisation and are to be conducted in line with the FDA Project Optimus guidance. They should be reported even if no association between the patients' sex and the activity and/or toxicity of an anticancer drug has been identified.

Model-based population pharmacokinetic and exposure response analyses for safety and efficacy of nivolumab as adjuvant treatment in subjects with resected oesophageal or gastroesophageal junction cancer

AIMS

Nivolumab is approved as adjuvant treatment in subjects with resected oesophageal or gastroesophageal junction cancer (EC/GEJC) based on results from the pivotal CheckMate 577 trial. We present a model-based clinical pharmacology profiling and benefit-risk assessment of nivolumab as adjuvant treatment in subjects with resected EC/GEJC supporting a less frequent dosing regimen.

METHODS

Population pharmacokinetic (popPK) analysis was conducted to characterize nivolumab pharmacokinetics (PK) using clinical data from 1493 subjects from seven monotherapy clinical studies across multiple solid tumours. The exposure-response (E-R) analyses included data from 756 patients from CheckMate 577. E-R relationships for efficacy and safety were characterized by evaluating the relationship between nivolumab exposure and disease-free survival (DFS) for efficacy; and time to first occurrence of Grade ≥2 immune-mediated adverse events (Gr2 + IMAEs) for safety.

RESULTS

Nivolumab exposure was found to be associated with both DFS and risk of Gr2 + IMAEs. However, the hazard ratios (HRs) (95% confidence interval [CI]) at the 5th and 95th percentiles of nivolumab exposure were similar for DFS and Gr2 + IMAEs, indicating flat E-R relationships within the exposure range produced by the studied regimen. Model-predicted probability of DFS and Gr2 + IMAEs were similar between the two regimens of 240 mg every 2 weeks or 480 mg every 4 weeks for 16 weeks followed by 480 mg Q4W up to 1 year.

CONCLUSIONS

The analyses demonstrated a flat E-R relationship over the range of exposures produced by the studied regimen and supported the approval of an alternative dosing regimen with less frequent dosing in patients with adjuvant EC/GEJC.

Pharmacokinetics, Safety, and Immunogenicity of a Biosimilar of Nivolumab (LY01015): A Randomized, Double-Blind, Parallel-Controlled Phase I Clinical Trial in Healthy Chinese Male Subjects

BACKGROUND

Nivolumab (Opdivo®) is the first anti-PD-1 antibody approved in the world. LY01015 is a potential biosimilar of nivolumab.

OBJECTIVES

This phase I study aimed to establish the pharmacokinetic equivalence between LY01015 and the original investigational nivolumab (Opdivo®) in healthy Chinese male subjects. Additionally, safety and immunogenicity were assessed.

PATIENTS AND METHODS

A randomized, double-blind, parallel-controlled, phase I trial was conducted with 176 healthy male adults receiving a single intravenous infusion of LY01015 or nivolumab at 0.3 mg/kg. Pharmacokinetics, safety, and immunogenicity were evaluated over a 99-day period. The primary pharmacokinetics endpoint was AUC0-∞, and the secondary pharmacokinetic endpoints included AUC0-t and Cmax. Pharmacokinetic bioequivalence was confirmed using standard equivalence margins of 80.00-125.00%.

RESULTS

This study is the first to report on the pharmacokinetics, safety, and immunogenicity of Opdivo® in healthy individuals. The pharmacokinetics profiles of LY01015 and Opdivo® were found to be comparable. The geometric mean ratios (90% confidence intervals) for the AUC0-∞, AUC0-t, and Cmax of LY01015 to Opdivo® were 94.49% (90.29-98.88%), 94.92% (88.73-101.54%), and 96.55% (93.32-99.90%), respectively, falling within the conventional bioequivalence criteria of 80.00-125.00%. The safety and immunogenicity were also comparable between the two groups.

CONCLUSIONS

LY01015 demonstrated highly similar pharmacokinetics to nivolumab in healthy Chinese male subjects. Both drugs exhibited comparable safety and immunogenicity profiles.

TRIAL REGISTRATION

This trial is registered at the Chinese Clinical Trial Registry website ( https://www.chictr.org.cn/ #ChiCTR2200064771).

Pharmacokinetics and clinical outcomes of low-dose nivolumab relative to conventional dose in patients with advanced cancer

PURPOSE

Nivolumab is approved at various doses, including 3 mg/kg, 240 mg and 480 mg flat doses at various dosing intervals. The concept of low-dose immunotherapy is gaining traction in recent years. However, there is a need to better understand the pharmacokinetics and clinical outcomes at lower doses.

METHODS

Patients were either administered 40 mg flat dose or 3 mg/kg Q2W/Q3W, depending on affordability as per prevailing hospital practice. All patients were hospitalized on day 1 and pharmacokinetic samples were collected at 0, 0.5, 1.0, 6.0, 24.0, 72.0 h and day 14 following administration of the first dose of nivolumab. Plasma nivolumab levels were measured by ELISA. Patients were followed up for response and toxicity.

RESULTS

Twenty five patients were included in the study. Fourteen received nivolumab at conventional dose (3 mg/kg), while 11 patients received low-dose (40 mg flat). The geometric means of dose normalized Cmax and AUC0-t were comparable between those who received conventional dose and low-dose of nivolumab (0.28 versus 0.23 µg/mL/mg and 0.0014 versus 0.0011 d/mL respectively). Nineteen patients were evaluable for response. ORR among patients who received conventional dose was 5/11 (45.5%) whereas it was 4/9 (44.4%) in the low-dose cohort. All 14 (100%) patients in conventional dosing group and 7/11 patients (63.64%) in low-dose group had treatment emergent adverse events. Grade ≥ 3 toxicities were observed in 4/14 patients in conventional dose group and none in low-dose group.

CONCLUSION

Low-dose nivolumab leads to lower exposure in patients as compared with conventional dose, but low-dose was better tolerated, while response rates were comparable to conventional dose.

Low serum concentrations of bevacizumab and nivolumab owing to excessive urinary loss in patients with proteinuria: a case series

PURPOSE

Proteinuria can cause interindividual variability in the pharmacokinetics of therapeutic antibodies and may affect therapeutic efficacy. Here, we measured the serum and urinary concentrations of bevacizumab (BV) and nivolumab (NIVO) in patients with proteinuria and reported a case series of these patients.

METHODS

Thirty-two cancer patients who received BV every 3 weeks or NIVO every 2 weeks between November 2020 and September 2021 at Kyoto University Hospital were enrolled in this study. The serum and urinary concentrations of BV and NIVO were measured using liquid chromatography-tandem mass spectrometry.

RESULTS

We divided the BV-treated patients and the NIVO-treated patients into two groups based on the urine protein-creatinine ratio (UPCR): UPCR 1 g/g or higher (BV, n = 9; NIVO, n = 3) and UPCR less than 1 g/g (BV, n = 14; NIVO, n = 6). Serum concentrations of the therapeutic antibodies adjusted by their doses were significantly lower in both BV- and NIVO-treated patients with UPCR 1 g/g or higher compared to those with less than 1 g/g. In patients with UPCR 1 g/g or higher, urinary concentrations of the therapeutic antibodies adjusted by their serum concentrations and urinary creatinine concentrations tended to increase.

CONCLUSION

This case-series study suggests a possibility of reduction in serum concentrations of BV and NIVO in patients with proteinuria by urinary excretion of these drugs.

Formulation and Validation of an Extended Sigmoid Emax Model in Pharmacodynamics

PURPOSE OR OBJECTIVE

Drug concentration-response curves (DRCs) are crucial in pharmacology for assessing the drug effects on biological systems. The widely used sigmoid Emax model, which accounts for response saturation, relies heavily on the effective drug concentration ( E D 50 ). This reliance can lead to validation errors and inaccuracies in model fitting. The Emax model cannot generate multiple DRCs, raising concerns about whether the dataset is fully utilized.

METHODS

This study formulates an extended Emax (eEmax) model designed to overcome these limitations. The eEmax model generates multiple DRCs from a single dataset by using various estimatedα ' s ∈ 0,100 , while keeping E D α fixed, rather than estimating an E D 50 value as in the Emax model.

RESULTS

This model effectively captures a broader range of concentration-response behavior, including non-sigmoidal patterns, thus providing greater flexibility and accuracy compared to the Emax model. Validation using various drug-response data and PKPD frameworks demonstrates the eEmax model's improved accuracy and versatility in handling concentration-response data.

CONCLUSIONS

The eEmax model provides a robust and flexible method for drug concentration-response analysis, facilitating the generation of multiple DRCs from a single dataset and reducing the possibility of validation errors. This model is particularly valuable for its ease of use and its capability to fully utilize datasets, providing its potential in PKPD modeling and drug discovery.

Informing the Recommended Phase III Dose of Alnuctamab, a CD3 × BCMA T-Cell Engager, Using Population Pharmacokinetics and Exposure-Response Analysis

Alnuctamab, a B-cell maturation antigen (BCMA)-targeting T-cell engager, has demonstrated encouraging antitumor activity in the phase I study CC-93269-MM-001 treating patients with relapsed or refractory multiple myeloma. Identification of a recommended Phase III dose (RP3D) was a key objective, as such population pharmacokinetic (PopPK) and exposure-response analysis was critical. Intravenous (IV) alnuctamab was administered in fixed doses (0.15-10 mg) or in step-up doses to a maximum 10-mg target dose. Subcutaneous (SC) step-up doses of 3 and 6 mg were followed by a target dose range of 10-60 mg. Concentration data from IV and SC alnuctamab administration was pooled and was well described by a two-compartment PopPK model with first-order absorption and elimination. Covariate analysis determined that the inclusion of baseline soluble BCMA (sBCMA) on clearance significantly improved model fitting. Individual exposure parameters were estimated from the final model to characterize exposure-response relationships. Switching from IV to SC administration improved the safety profile of alnuctamab by limiting the frequency of grade ≥2 CRS events. A significant exposure-CRS relationship was observed after the first SC dose, but not subsequent dose administrations. Exposure-safety analysis did not find a statistically significant relationship between increasing exposure and the probability of key safety events of interest. Logistic regression analysis for patients administered SC alnuctamab identified that increased exposure significantly increased the probability of response, although the additional benefit was minimal at exposures above 30 mg target dose. Considering the totality of exposure-response data, the clinical pharmacology assessment supported a SC RP3D of 3/6/30 mg.

Population Pharmacokinetics and Exposure-Response Relationship of Zimberelimab in Chinese Patients with Advanced Tumors

This study aimed to establish a population pharmacokinetic (PopPK) model using data from 2 clinical trials of zimberelimab, evaluate the pharmacokinetics (PKs) of zimberelimab, explore the feasibility of 360 mg once every 3 weeks (Q3W) and 480 mg once every 4 weeks (Q4W) as alternative dosage regimens, and analyze the exposure-response relationship of the efficacy and safety of zimberelimab for advanced tumors. The PKs of zimberelimab were described using the 2-compartment model with time-dependent nonlinear elimination. The prediction-corrected visual predictive check was used to evaluate the model's predictive value on blood drug concentrations. In total, 2165 PK observations from 321 participants were included. The PopPK model demonstrated a high level of concordance between the observed data and the predicted values, indicative of a robust fit to the PK data of zimberelimab. The PK variables were similar for the 240 mg once every 2 weeks, 360 mg Q3W, and 480 mg Q4W regimens. No covariates significantly affecting the PK variables in the final model were found. The exposure variables of zimberelimab have no obvious correlations with efficacy and safety, and 360 mg Q3W and 480 mg Q4W are worthy of further study. This study establishes a PopPK model and analyzes the exposure-response relationship of zimberelimab, which helps to explore the potential for alternative dosing regimens and offers a foundation for optimizing therapeutic strategies for advanced cancer patients through simulation-based methods.

Evaluation of safety outcomes between nivolumab regimens with differing dosing patterns

BACKGROUND

Real-world safety outcomes between the two flat-dose nivolumab regimens demonstrated to be similar in a study of adjuvant nivolumab recipients for melanoma. However, this study was limited by a single oncology patient population, a small sample size, and insufficient study power. The primary objective of this study was to evaluate the incidence of immunotherapy-related adverse effects (irAEs) between nivolumab regimens with differing dosing patterns in various solid tumor patient populations.

METHODS

Single-center retrospective cohort study of adult patients with solid tumor malignancies who received nivolumab 240 mg Q2W or 480 mg Q4W, or who were transitioned from 240 mg Q2W to 480 mg Q4W from March 1, 2018 to March 31, 2022 were selected for analysis from an electronic health record generated report. The primary endpoint evaluated was the incidence of irAEs. Secondary endpoints included the incidence of significant irAEs and reasons for treatment discontinuation. These endpoints were compared by univariate analysis between all three cohorts. A multivariate analysis was then conducted for the primary endpoint.

RESULTS

Nivolumab 240 mg Q2W was associated with a statistically significant increase in the incidence of colitis whereas the 480 mg Q4W regimen was associated with a statistically significant increase in the incidence of pruritis. The incidence of irAEs was not different between the three cohorts, while the incidence of significant irAEs was higher in the 240 mg Q2W and 240 mg Q2W to 480 mg Q4W cohorts.

CONCLUSION

Clinicians ought to be aware of differences in the irAE profiles between nivolumab regimens with differing dosing patterns.

Model-Informed Clinical Pharmacology Profile of a Novel Fixed-Dose Combination of Nivolumab and Relatlimab in Adult and Adolescent Patients with Solid Tumors

PURPOSE

Progression-free survival (PFS) was significantly improved with nivolumab 480 mg plus relatlimab 160 mg fixed-dose combination (FDC) every 4 weeks (Q4W) versus nivolumab alone in patients with previously untreated advanced melanoma in RELATIVITY-047. In addition, RELATIVITY-020 (Part D) demonstrated a manageable safety profile and potential for durable response with nivolumab plus relatlimab in previously treated patients. Here, we evaluate the clinical pharmacology profile (CPP) of nivolumab plus relatlimab to support the approved regimen for adult and adolescent patients with advanced melanoma and its continued clinical development in solid tumors.

EXPERIMENTAL DESIGN

The pharmacokinetics (PK) and immunogenicity of relatlimab and nivolumab were assessed using data from RELATIVITY-047 and RELATIVITY-020. Patients with advanced solid tumors received relatlimab alone or nivolumab plus relatlimab as single-agent vials (SAV) or FDC. PK was characterized using a population PK (popPK) model.

RESULTS

Relatlimab demonstrated nonlinear and time-varying PK. Nonlinearity in relatlimab PK represented approximately 31% of total CL of relatlimab 160 mg Q4W. Relatlimab PK was dose proportional at doses ≥160 mg Q4W. Geometric mean exposures were similar for SAV and FDC cohorts receiving equivalent dosing regimens. No dose adjustment was required for covariates. Incidence of relatlimab antidrug antibodies was <6% for nivolumab plus relatlimab and had no clinically meaningful impact. There was no PK-related drug interaction of nivolumab plus relatlimab.

CONCLUSIONS

The CPP of relatlimab alone or in combination with nivolumab supports the approved dosing in advanced melanoma and the continued evaluation of nivolumab and relatlimab across other solid tumors. See related commentary by Gopalakrishnan and Amaria, p. 2862.

Extending the dosing intervals of nivolumab: model-based simulations in unselected cancer patients

BACKGROUND

Reducing nivolumab dose intensity could increase patients' life quality and decrease the financial burden while maintaining efficacy. The aims of this study were to develop a population PK model of nivolumab based on data from unselected metastatic cancer patients and to simulate extended-interval regimens allowing to maintain minimal effective plasma concentrations (MEPC).

METHODS

Concentration-time data (992 plasma nivolumab concentrations, 364 patients) were modeled using a two-compartment model with linear elimination clearance in Monolix software. Extended-interval regimens allowing to maintain steady-state trough concentrations (Cmin,ss) above the MEPC of 2.5 mg/L or 1.5 mg/L in >90% of patients were simulated.

RESULTS

Increasing 3-times the dosing interval from 240 mg every two weeks (Q2W) to Q6W and 2-times from 480 mg Q4W to Q8W resulted in Cmin,ss above 2.5 mg/L in 95.8% and 95.4% of patients, respectively. 240 mg Q8W and 480 mg Q10W resulted in Cmin,ss above 1.5 mg/L in 91.0% and 91.8% of patients, respectively. Selection of a 240 mg Q6W regimen would decrease by 3-fold the annual treatment costs compared to standard regimen of 240 mg Q2W (from 78,744€ to 26,248€ in France).

CONCLUSIONS

Clinical trials are warranted to confirm the non-inferiority of extended-interval compared to standard regimen.

Safety and efficacy of nivolumab therapy in patients with metastatic renal cell carcinoma and impaired kidney function

INTRODUCTION

Patients with renal insufficiency, usually defined as those with creatinine clearance < 40 mL/min, were excluded from pivotal clinical trials, especially in studies involving nivolumab therapy in patients with renal cell carcinoma (RCC). The aim of the study is to evaluate the efficacy and safety of nivolumab in patients with metastatic RCC (mRCC) stratified according to creatinine clearance.

MATERIAL AND METHODS

Data from mRCC patients treated with nivolumab were retrospectively analyzed. Patients were classified into two categories according to their estimated glomerular filtration rate (eGFR); the first category (C1) included patients with eGFR < 40 mL/min/1.73 m2 and the second category (C2) included those with eGFR ≥ 40 mL/min/1.73 m2.

RESULTS

Of the 95 patients enrolled, 1. group included 26 patients (27.4%) and 2. group included 69 patients (72.6%). None of the pts in category 1 were on hemodialysis. Overall incidence of adverse events was not statistically different between the two groups (P = .469). The overall response rate ORR was 50% in the first group and 42.0% in the second group (P = .486). Median overall survival (OS) was longer with 23.3 months in the 2. group versus 11 months in the 1. group (P = .415).

CONCLUSION

Renal insufficiency is a common problem in patients with advanced renal cancer since they often undergo nephrectomy and their renal function may also worsen while receiving tyrosine kinase inhibitor therapy. We found that there is no significant difference in the safety and efficacy of nivolumab treatment between two groups. Nivolumab appears to be a safe and effective agent in patients with renal impairment.

Utility and impact of quantitative pharmacology on dose selection and clinical development of immuno-oncology therapy

Immuno-oncology (IO) therapies have changed the cancer treatment landscape. Immune checkpoint inhibitors (ICIs) have improved overall survival in 20-40% of patients with malignancies that were previously refractory. Due to the uniqueness in biology, modalities and patient responses, drug development strategies for IO differed from that traditionally used for cytotoxic and target therapies in oncology, and quantitative pharmacology utilizing modeling approach can be applied in all phases of the development process. In this review, we used case studies to showcase how various modeling methodologies were applied from translational science and dose selection through to label change, using examples that included anti-programmed-death-1 (anti-PD-1), anti-programmed-death ligand-1 (anti-PD-L1), anti-cytotoxic T-lymphocyte-associated protein 4 (anti-CTLA-4), and anti-glucocorticoid-induced tumor necrosis factor receptor-related protein (anti-GITR) antibodies. How these approaches were utilized to support phase I-III dose selection, the design of phase III trials, and regulatory decisions on label change are discussed to illustrate development strategies. Model-based quantitative approaches have positively impacted IO drug development, and a better understanding of the biology and exposure-response relationship may benefit the development and optimization of new IO therapies.

Association Between Kidney Function and Outcomes Following Immune Checkpoint Inhibitor-Based Combination Therapy in Patients With Advanced Renal Cell Carcinoma

BACKGROUND

It remains unclear whether kidney function affects outcomes following immune checkpoint inhibitor (ICI)-based combination therapy for advanced renal cell carcinoma (RCC).

METHODS

We retrospectively evaluated data of 167 patients with advanced RCC, including 98 who received ICI dual combination therapy (ie, immunotherapy [IO]-IO) and 69 who received ICI combined with tyrosine kinase inhibitor (TKI) (ie, IO-TKI). In each regimen, treatment profiles were assessed according to the grade of chronic kidney disease (CKD) as defined by the KDIGO 2012 criteria.

RESULTS

Of the 98 patients who received IO-IO, 31 (32%), 30 (31%), 15 (15%), and 22 (22%) had CKD G1/2, G3a, G3b, and G4/5, respectively. Of the 69 patients who received IO-TKI, 18 (26%), 25 (36%), and 26 (38%) had G1/2, G3a, and G3b/4/5, respectively. Regarding efficacy, progression-free survival, overall survival, or objective response rate was not different according to the CKD grade in both treatment groups (P > .05). Regarding safety, the rate of adverse events, treatment interruption, or corticosteroid administration was not different according to the CKD grade in the IO-IO group (P > .05), whereas in the IO-TKI group, the incidence of grade ≥ 3 adverse events were significantly higher (P = .0292), and the rates of ICI interruption (P = .0353) and corticosteroid administration (P = .0685) increased, according to the CKD grade.

CONCLUSION

There is a differential safety but comparable efficacy profile between the IO-IO and IO-TKI regimens in patients with CKD. Further prospective studies are required to confirm these findings.

PD-1/PD-L1 inhibitors associated hypophysitis: An analysis from the FAERS database and case reports

To get a thorough understanding of PD-1/L1 inhibitor-related hypophysitis (PD-1/L1-irH), we utilized a combination of disproportionality analysis and case analysis to comprehensively characterize the clinical features of PD-1/L1-irH. Significant signals of hypophysitis were detected for all PD-1/PD-L1 inhibitors in the FAERS (FDA Adverse Event Reporting System). As revealed by both FAERS and the case analysis, PD-1/L1-irH occurred more commonly in males, PD-1 inhibitors users and patients older than 65 years. The median onset time was 101 days in FAERS and 8 cycles in the case analysis. In the case analysis, eight late-onset PD-1/L1-irHs occurred even after a discontinuation of several months (4-15 months). As revealed in FAERS, the outcome of PD-1/L1-irH tended to be poor, generally resulting in 64.66% hospitalization and 12.59% death. Fatigue was the most prominent symptom of PD-1/L1-irH, followed by anorexia, hyponatremia, and hypotension, as revealed by the analysis of 84 cases. Meanwhile isolated adrenocorticotropic (ACTH) deficiency was particularly prevalent for PD-1/L1-irH (85.71%), while gonadal hormones or posterior pituitary hormones deficiencies were rare. Glucocorticoids were administered to almost all cases (81/84), with a physiologic or stress dosage in 61.9% of cases, and a high-dose in 26.2% of cases. Most cases (58.3%) showed a favorable tumor response before diagnosis of PD-1/L1-irH. PD-1/L1-irH may occur throughout the whole therapy period even after discontinuation. Clinicians should pay more attention to PD-1 inhibitor users, males and older patients. Early diagnosis and prompt managements are crucial for PD-1/L1-irH as its potentially life-threatening nature.

Metastatic Melanoma Treatment in Special Populations

ABSTRACT

This review outlines the most up-to-date metastatic melanoma treatment recommendations and relevant risks for patients with solid organ transplants, patients with renal dysfunction, and patients with preexisting autoimmune conditions. These specific treatment populations were excluded from the original clinical trials, which studied immune checkpoint inhibitors and BRAF/MEK inhibitors in the advanced melanoma setting. We have synthesized the current body of literature, mainly case series and retrospective analyses, to reflect the evidence for the treatment of these special patient populations at present.

Antibody Drug Clearance: An Underexplored Marker of Outcomes with Checkpoint Inhibitors

Immune-checkpoint inhibitor (ICI) therapy has dramatically changed the clinical landscape for several cancers, and ICI use continues to expand across many cancer types. Low baseline clearance (CL) and/or a large reduction of CL during treatment correlates with better clinical response and longer survival. Similar phenomena have also been reported with other monoclonal antibodies (mAb) in cancer and other diseases, highlighting a characteristic of mAb clinical pharmacology that is potentially shared among various mAbs and diseases. Though tempting to attribute poor outcomes to low drug exposure and arguably low target engagement due to high CL, such speculation is not supported by the relatively flat exposure-response relationship of most ICIs, where a higher dose or exposure is not likely to provide additional benefit. Instead, an elevated and/or increasing CL could be a surrogate marker of the inherent resistant phenotype that cannot be reversed by maximizing drug exposure. The mechanisms connecting ICI clearance, therapeutic efficacy, and resistance are unclear and likely to be multifactorial. Therefore, to explore the potential of ICI CL as an early marker for efficacy, this review highlights the similarities and differences of CL characteristics and CL-response relationships for all FDA-approved ICIs, and we compare and contrast these to selected non-ICI mAbs. We also discuss underlying mechanisms that potentially link mAb CL with efficacy and highlight existing knowledge gaps and future directions where more clinical and preclinical investigations are warranted to clearly understand the value of baseline and/or time-varying CL in predicting response to ICI-based therapeutics.

Model-Based Dose Selection of Subcutaneous Nivolumab in Patients with Advanced Solid Tumors

The pharmacokinetics (PK) of intravenous (i.v.) nivolumab is well characterized. A subcutaneous (s.c.) nivolumab formulation with and without recombinant human hyaluronidase PH20 enzyme is being evaluated in CheckMate 8KX (NCT03656718). A model-based analysis was conducted to characterize the PK of nivolumab s.c. and predict systemic exposures after i.v. and s.c. administration to guide dosing regimen selection for nivolumab s.c. A prior i.v. model was modified to incorporate an s.c. extravascular compartment and estimate the absorption rate constant and bioavailability of nivolumab s.c. Serum concentration-time data from 82 patients treated with nivolumab s.c. 720, 960, or 1,200 mg were pooled with existing i.v. data from multiple studies for model development. Prediction-corrected visual predictive check (pcVPC) plots assessed the model's performance. Stochastic simulations were conducted to predict exposures for i.v. and s.c. administration. The data were described by a two-compartment model with time-varying clearance, zero-order infusion into the central compartment after i.v. dosing, and first-order absorption from the extravascular compartment after s.c. dosing. The pcVPC suggested that the model adequately described the observed nivolumab s.c. data. Predicted nivolumab exposures at 1,200 mg s.c. every 4 weeks (q4w) were higher than those at the approved dose of 3 mg/kg i.v. q2w and lower than those at the highest tested safe dose of 10 mg/kg i.v. q2w. Nivolumab PK is well-characterized using the combined s.c./i.v. population PK model. The model-based analysis facilitated a comprehensive benefit-risk assessment of nivolumab s.c. and informed selection of 1,200 mg s.c. q4w for phase III evaluation.

Immune checkpoint inhibitors and risk of immune-mediated adverse events: a cohort study comparing extended versus standard interval administration

The COVID-19 pandemic precipitated the implementation of extended interval immune checkpoint inhibitors (ICIs) in an effort to limit hospital visits, but few studies have examined their safety. This study aimed to compare in oncology outpatients, immune-mediated adverse events (IMAEs) in terms of total number, incidence, severity, and time to occurrence, based on exposure to standard or extended interval ICIs. A retrospective cohort study was conducted in patients who received at least one dose of an ICI between 2015 and 2021. Data were collected from patient records and pharmacy software. Adjusted logistic, Poisson, and Cox regression models were estimated. A total of 310 patients with a mean age of 67.1 years were included, 130 of whom had the extended interval. No statistically significant differences were observed between the groups. With the standard and extended intervals, the mean total number of IMAE per participant was 1.02 and 1.18, respectively; the incidence of an IMAE was 62% and 64%. Of the 147 IMAE episodes in the standard interval group, 14 (9.5%) were grade 3 or higher, while there were 15 (12.4%) among the 121 IMAE episodes in the extended interval group. Compared with standard interval, the use of extended interval did not increase the risk of having a first IMAE (adjusted hazard ratio 0.92 (95% CI 0.67-1.26)). This study suggests that the administration of an ICI according to extended interval is as safe as the administration according to standard interval in oncology outpatients.

Characterization of anti-drug antibody dynamics using a bivariate mixed hidden-markov model by nonlinear-mixed effects approach

Biological therapies may act as immunogenic triggers leading to the formation of anti-drug antibodies (ADAs). Population pharmacokinetic (PK) models can be used to characterize the relationship between ADA and drug disposition but often rely on the ADA bioassay results, which may not be sufficiently sensitive to inform on this characterization.In this work, a methodology that could help to further elucidate the underlying ADA production and impact on the drug disposition was explored. A mixed hidden-Markov model (MHMM) was developed to characterize the underlying (hidden) formation of ADA against the biologic, using certolizumab pegol (CZP), as a test drug. CZP is a PEGylated Fc free TNF-inhibitor used in the treatment of rheumatoid arthritis and other chronic inflammatory diseases.The bivariate MHMM used information from plasma drug concentrations and ADA measurements, from six clinical studies (n = 845), that were correlated through a bivariate Gaussian function to infer about two hidden states; production and no-production of ADA influencing PK. Estimation of inter-individual variability was not supported in this case. Parameters associated with the observed part of the model were reasonably well estimated while parameters associated with the hidden part were less precise. Individual state sequences obtained using a Viterbi algorithm suggested that the model was able to determine the start of ADA production for each individual, being a more assay-independent methodology than traditional population PK. The model serves as a basis for identification of covariates influencing the ADA formation, and thus has the potential to identify aspects that minimize its impact on PK and/or efficacy.

Time-dependent clearance can confound exposure-response analysis of therapeutic antibodies: A comprehensive review of the current literature

Exposure-response (ER) analysis is used to optimize dose and dose regimens during clinical development. Characterization of relationships between drug exposure and efficacy or safety outcomes can be utilized to make dose adjustments that improve patient response. Therapeutic antibodies typically show predictable pharmacokinetics (PK) but can exhibit clearance that decreases over time due to treatment. Moreover, time-dependent changes in clearance are frequently associated with drug response, with larger decreases in clearance and increased exposure seen in patients who respond to treatment. This often confounds traditional ER analysis, as drug response influences exposure rather than the reverse. In this review, we survey published population PK analyses for reported time-dependent drug clearance effects across 158 therapeutic antibodies approved or in regulatory review. We describe the mechanisms by which time-dependent clearance can arise, and evaluate trends in frequency, magnitude, and time scale of changes in clearance with respect to indication, mechanistic interpretation of time-dependence, and PK modeling techniques employed. We discuss the modeling and simulation strategies commonly used to characterize time-dependent clearance, and examples where time-dependent clearance has impeded ER analysis. A case study using population model simulation was explored to interrogate the impact of time-dependent clearance on ER analysis and how it can lead to spurious conclusions. Overall, time-dependent clearance arises frequently among therapeutic antibodies and has spurred erroneous conclusions in ER analysis. Appropriate PK modeling techniques aid in identifying and characterizing temporal shifts in exposure that may impede accurate ER assessment and successful dose optimization.

Pediatric model-based dose optimization using a pooled exposure-response safety analysis for nivolumab and nivolumab plus ipilimumab combination in melanoma

An exposure-response (E-R) safety analysis was conducted across adult and pediatric (<18 years) studies to evaluate the potential impact of higher nivolumab and/or ipilimumab exposures in adolescents (≥12 to <18 years) versus adults with melanoma using the approved adult dosing regimens for nivolumab alone or in combination with ipilimumab. Data from 3507 patients across 15 studies were used to examine the relationship between nivolumab-ipilimumab daily average exposure and time to grade 2+ immune-mediated adverse events (gr2+ IMAEs). Results from the E-R safety model showed ipilimumab, but not nivolumab, exposure to be a statistically significant predictor of gr2+ IMAEs. Significant covariates included sex (41% higher risk for women than men), line of therapy (19% higher for first-line than later-line), and treatment setting (26% lower for adjuvant than advanced melanoma). Younger age and lower body weight (BW) were each associated with a lower risk of gr2+ IMAEs (hazard ratio [HR]: 0.830 for 15-year-olds versus 60-year-olds and 0.84 for BW 52 kg versus 75 kg). For adolescents with melanoma treated with nivolumab in the advanced or adjuvant settings, these results are supportive of nivolumab flat dosing regimens for adolescents greater than or equal to 40 kg and BW-based dosing for adolescents less than 40 kg. These results also support adult weight-based dosing regimens for nivolumab plus ipilimumab in adolescents with advanced melanoma. This analysis suggests that although higher exposures are predicted in adolescents with lower weight compared with adults, there is no predicted immune-mediated safety risk when treated with the approved adult dosing of nivolumab with/without ipilimumab.

Exploring Differences in Pharmacometrics of Rabeprazole between Genders via Population Pharmacokinetic-Pharmacodynamic Modeling

Rabeprazole is a proton pump inhibitor that inhibits gastric acid production and increases gastric pH; it is widely used clinically as a treatment option for gastritis and gastric ulcers. However, information on the inter-individual variability of rabeprazole pharmacometrics, which is a key element in establishing its scientific clinical use, is still lacking. Particularly, the differences in pharmacokinetics between genders and the degree of variation in pharmacodynamics have not been clearly identified. Thus, the main purpose of this study was to explore any differences in rabeprazole pharmacokinetics between genders and to quantitatively predict and compare the effects of any differences in pharmacokinetics between genders on known pharmacodynamics using population pharmacokinetic-pharmacodynamic modeling. To compare pharmacokinetics and modeling data between genders, bioequivalence results were used simultaneously on healthy Korean men and women using the physiological and biochemical parameters derived from each individual. Pharmacodynamic modeling was performed based on the data of previously reported gastric pH changes in response to rabeprazole plasma concentrations, which was co-linked to the central compartmental bioavailable concentration in the population pharmacokinetic model. There was no significant difference in the level of rabeprazole exposure and elimination of plasma between genders following oral administration of 10 mg enteric-coated rabeprazole tablets; however, there was a clear delay in absorption in women compared to men. Additionally, a comparison of pharmacokinetic parameters normalized to body weight between genders showed that the maximum plasma concentrations were significantly higher in women than in men, again suggesting gender differences in rabeprazole absorption. The population pharmacokinetic profiles for rabeprazole were described using a three-sequential multi-absorption with lag time (Tlag) two-compartment model, whereas body surface area and gender were explored as effective covariates for absorption rate constant and Tlag, respectively. The effect of increased gastric pH due to plasma exposure to rabeprazole was explained using the Sigmoid Emax model, with the baseline as a direct response. The significantly longer rabeprazole Tlag in females delayed the onset of an effect by an average of 1.58 times (2.02-3.20 h), yet the overall and maximum effects did not cause a significant difference within 15%. In the relative comparison of the overall efficacy of rabeprazole enteric-coated tablet administration between genders, it was predicted based on the model that males would have higher efficacy. This study will be very useful in broadening the perspective of interpreting drug diversity between individuals and narrowing the gap in knowledge related to scientific precision medicine by presenting new information on gender differences in rabeprazole pharmacometrics that had not been previously identified.

A Minimal PBPK Model for Plasma and Cerebrospinal Fluid Pharmacokinetics of Trastuzumab after Intracerebroventricular Administration in Patients with HER2-Positive Brain Metastatic Localizations

BACKGROUND

Dosing regimens of trastuzumab administered by intracerebroventricular (icv) route to patients with HER2-positive brain localizations remain empirical. The objectives of this study were to describe pharmacokinetics (PK) of trastuzumab in human plasma and cerebrospinal fluid (CSF) after simultaneous icv and intravenous (iv) administration using a minimal physiologically-based pharmacokinetic model (mPBPK) and to perform simulations of alternative dosing regimens to achieve therapeutic concentrations in CSF.

METHODS

Plasma and CSF PK data were collected in two patients with HER2-positive brain localizations. A mPBPK model for mAbs consisting of four compartments (tight and leaky tissues, plasma and lymph) was enriched by an additional compartment for ventricular CSF. The comparison between observed and model-predicted concentrations was evaluated using prediction error (PE).

RESULTS

The developed mPBPK model described plasma and CSF trastuzumab concentrations reasonably well with mean PE for plasma and CSF data of 41.8% [interquartile range, IQR = -9.48; 40.6] and 18.3% [-36.7; 60.6], respectively, for patient 1 and 11.4% [-10.8; 28.7] and 22.5% [-27.7; 77.9], respectively, for patient 2. Trastuzumab showed fast clearance from CSF to plasma with Cmin,ss of 0.56 and 0.85 mg/L for 100 and 150 mg q1wk, respectively. Repeated dosing of 100 and 150 mg q3day resulted in Cmin,ss of 10.3 and 15.4 mg/L, respectively. Trastuzumab CSF target concentrations are achieved rapidly and maintained above 60 mg/L from 7 days after a continuous perfusion at 1.0 mg/h.

CONCLUSION

Continuous icv infusion of trastuzumab at 1.0 mg/h could be an alternative dosing regimen to rapidly achieve intraventricular CSF therapeutic concentrations.

Population Pharmacokinetics and Exposure-Response with Teclistamab in Patients With Relapsed/Refractory Multiple Myeloma: Results From MajesTEC-1

BACKGROUND

Teclistamab, a B-cell maturation antigen × CD3 bispecific antibody, is approved in patients with relapsed/refractory multiple myeloma (RRMM) who have previously received an immunomodulatory agent, a proteasome inhibitor, and an anti-CD38 antibody.

OBJECTIVE

We report the population pharmacokinetics of teclistamab administered intravenously and subcutaneously (SC) and exposure-response relationships from the phase I/II, first-in-human, open-label, multicenter MajesTEC-1 study.

METHODS

Phase I of MajesTEC-1 consisted of dose escalation and expansion at the recommended phase II dose (RP2D; 1.5 mg/kg SC weekly, preceded by step-up doses of 0.06 and 0.3 mg/kg); phase II investigated the efficacy of teclistamab RP2D in patients with RRMM. Population pharmacokinetics and the impact of covariates on teclistamab systemic exposure were assessed using a 2-compartment model with first-order absorption for SC and parallel time-independent and time-dependent elimination pathways. Exposure-response analyses were conducted, including overall response rate (ORR), duration of response (DoR), progression-free survival (PFS), overall survival (OS), and the incidence of grade ≥ 3 anemia, neutropenia, lymphopenia, leukopenia, thrombocytopenia, and infection.

RESULTS

In total, 4840 measurable serum concentration samples from 338 pharmacokinetics-evaluable patients who received teclistamab were analyzed. The typical population value of time-independent and time-dependent clearance were 0.449 L/day and 0.547 L/day, respectively. The time-dependent clearance decreased rapidly to < 10% after 8 weeks of teclistamab treatment. Patients who discontinue teclistamab after the 13th dose are expected to have a 50% reduction from Cmax in teclistamab concentration at a median (5th to 95th percentile) time of 15 days (7-33 days) after Tmax and a 97% reduction from Cmax in teclistamab concentration at a median time of 69 days (32-163 days) after Tmax. Body weight, multiple myeloma type (immunoglobulin G vs non-immunoglobulin G), and International Staging System (ISS) stage (II vs I and III vs I) were statistically significant covariates on teclistamab pharmacokinetics; however, these covariates had no clinically relevant effect on the efficacy of teclistamab at the RP2D. Across all doses, ORR approached a plateau at the concentration range associated with RP2D, and in patients who received the RP2D, a flat exposure-response curve was observed. No apparent relationship was observed between DoR, PFS, OS, and the incidence of grade ≥3 adverse events across the predicted exposure quartiles.

CONCLUSION

Body weight, myeloma type, and ISS stage impacted systemic teclistamab exposure without any clinically relevant effect on efficacy. The exposure-response analyses for ORR showed a positive trend with increasing teclistamab systemic exposure, with a plateau at the RP2D, and there was no apparent exposure-response trend for safety or other efficacy endpoints. These analyses support the RP2D of teclistamab in patients with RRMM.

CLINICAL TRIAL REGISTRATION

NCT03145181 (phase I, 09 May 2017); NCT04557098 (phase II, 21 September 2020).

Pembrolizumab plus chemotherapy for advanced non-small-cell lung cancer without tumor PD-L1 expression in Asia

Aim: We pooled patient-level data from three randomized controlled studies to evaluate the combination of pembrolizumab plus chemotherapy in patients with untreated advanced/metastatic non-small-cell lung cancer (NSCLC) and programmed cell death ligand 1 (PD-L1) tumor proportion score <1% in East Asia. Methods: The analysis included 107 patients from China, Japan, Korea, Thailand and Taiwan (pembrolizumab plus chemotherapy, n = 56; chemotherapy alone, n = 51). Results: For pembrolizumab plus chemotherapy versus chemotherapy alone, median overall survival was 21.3 versus 12.6 months (HR, 0.55 [95% CI: 0.35-0.87]) and median progression-free survival was 8.4 versus 6.0 months (HR, 0.64 [95% CI: 0.43-0.96]). Conclusion: The analysis supports the use of pembrolizumab in combination with platinum-based chemotherapy for East Asian patients with PD-L1-negative, advanced NSCLC.

Translation of Monoclonal Antibodies Pharmacokinetics from Animal to Human Using Physiologically Based Modeling in Open Systems Pharmacology (OSP) Suite: A Retrospective Analysis of Bevacizumab

Interspecies translation of monoclonal antibodies (mAbs) pharmacokinetics (PK) in presence of target-mediated drug disposition (TMDD) is particularly challenging. Incorporation of TMDD in physiologically based PK (PBPK) modeling is recent and needs to be consolidated and generalized to provide better prediction of TMDD regarding inter-species translation during preclinical and clinical development steps of mAbs. The objective of this study was to develop a generic PBPK translational approach for mAbs using the open-source software (PK-Sim® and Mobi®). The translation of bevacizumab based on data in non-human primates (NHP), healthy volunteers (HV), and cancer patients was used as a case example for model demonstration purpose. A PBPK model for bevacizumab concentration-time data was developed using data from literature and the Open Systems Pharmacology (OSP) Suite version 10. PK-sim® was used to build the linear part of bevacizumab PK (mainly FcRn-mediated), whereas MoBi® was used to develop the target-mediated part. The model was first developed for NHP and used for a priori PK prediction in HV. Then, the refined model obtained in HV was used for a priori prediction in cancer patients. A priori predictions were within 2-fold prediction error (predicted/observed) for both area under the concentration-time curve (AUC) and maximum concentration (Cmax) and all the predicted concentrations were within 2-fold average fold error (AFE) and average absolute fold error (AAFE). Sensitivity analysis showed that FcRn-mediated distribution and elimination processes must be accounted for at all mAb concentration levels, whereas the lower the mAb concentration, the more significant the target-mediated elimination. This project is the first step to generalize the full PBPK translational approach in Model-Informed Drug Development (MIDD) of mAbs using OSP Suite.

Exposure-response analysis for nivolumab plus ipilimumab combination therapy in patients with advanced hepatocellular carcinoma (CheckMate 040)

This analysis was conducted to inform dose selection of a combination of nivolumab plus ipilimumab for the treatment of sorafenib-experienced patients with hepatocellular carcinoma (HCC). CheckMate 040 is an open-label, multicohort, phase I/II trial in adults with advanced HCC that evaluated nivolumab monotherapy (0.1-10 mg/kg once every 2 weeks [q2w]) and the following three combinations of nivolumab plus ipilimumab: (1) nivolumab 1 mg/kg plus ipilimumab 3 mg/kg every 3 weeks (q3w) for four doses, followed by nivolumab monotherapy 240 mg q2w (arm A); (2) nivolumab 3 mg/kg plus ipilimumab 1 mg/kg q3w for four doses, followed by nivolumab monotherapy 240 mg q2w (arm B); and (3) nivolumab 3 mg/kg q2w plus ipilimumab 1 mg/kg every 6 weeks continuously (arm C). Exposure-response relationships (efficacy and safety) were characterized using nivolumab and ipilimumab concentrations after the first dose (Cavg1) as the exposure measure. Objective tumor response (OTR) and overall survival (OS) improvements were associated with increased ipilimumab exposure (OTR: odds ratio 1.45, 95% confidence interval [CI], 1.13-1.86; OS: hazard ratio 0.86, 95% CI 0.75-0.98), but not nivolumab exposure (OTR: odds ratio 0.99, 95% CI 0.97-1.02; OS: hazard ratio 1.08, 95% CI 0.89-1.32). Hepatic treatment-related and immune-mediated adverse events were more common in arm A than in arms B or C. Nivolumab 1 mg/kg plus ipilimumab 3 mg/kg q3w for four doses, followed by nivolumab monotherapy 240 mg q2w had the most favorable benefit:risk profile in patients with advanced HCC.

Evolving Landscape in Liver Transplantation for Hepatocellular Carcinoma: From Stage Migration to Immunotherapy Revolution

Liver transplantation (LT) represents the primary curative option for HCC. Despite the extension of transplantation criteria and conversion with down-staging loco-regional treatments, transplantation is not always possible. The introduction of new standards of care in advanced HCC including a combination of immune checkpoint inhibitor-based therapies led to an improvement in response rates and could represent a promising strategy for down-staging the tumor burden. In this review, we identify reports and series, comprising a total of 43 patients who received immune checkpoint inhibitors as bridging or down-staging therapies prior to LT. Overall, treated patients registered an objective response rate of 21%, and 14 patients were reduced within the Milan criteria. Graft rejection was reported in seven patients, resulting in the death of four patients; in the remaining cases, LT was performed safely after immunotherapy. Further investigations are required to define the duration of immune checkpoint inhibitors, their minimum washout period and the LT long-term safety of this strategy. Some randomized clinical trials including immunotherapy combinations, loco-regional treatment and/or tyrosine kinase inhibitors are ongoing and will likely determine the appropriateness of immune checkpoint inhibitors' administration before LT.

Therapeutic drug monitoring of immune checkpoint inhibitors: based on their pharmacokinetic properties and biomarkers

As a new means of oncology treatment, immune checkpoint inhibitors (ICIs) can improve survival rates in patients with resistant or refractory tumors. However, there are obvious inter-individual differences in the unsatisfactory response rate, drug resistance rate and the occurrence of immune-related adverse events (irAE). These questions have sparked interest in researchers looking for a way to screen sensitive populations and predict efficacy and safety. Therapeutic drug monitoring (TDM) is a way to ensure the safety and effectiveness of medication by measuring the concentration of drugs in body fluids and adjusting the medication regimen. It has the potential to be an adjunctive means of predicting the safety and efficacy of ICIs treatment. In this review, the author outlined the pharmacokinetic (PK) characteristics of ICIs in patients. The feasibility and limitations of TDM of ICIs were discussed by summarizing the relationships between the pharmacokinetic parameters and the efficacy, toxicity and biomarkers.

Nivolumab combination therapy as first-line treatments for unresectable, advanced or metastatic esophageal squamous cell carcinoma

INTRODUCTION

Esophageal cancers continue to confer a dismal prognosis. Targeted and immune therapies have skyrocketed in the world of cancer management. Unlike other solid tumors, esophageal squamous cell carcinoma (ESCC) has lacked effective targeted therapy. Promising outcomes with immune checkpoint inhibitors (ICIs) have recently changed ESCC management.

AREAS COVERED

Nivolumab has been granted several approvals to treat ESCC patients. Nivolumab is recommended as adjuvant therapy for localized ESCC patients following trimodality therapy who have residual cancer in the surgical specimen (lymph node(s) and or the primary). CheckMate-648 led to dual ICI therapy approval with nivolumab plus ipilimumab or nivolumab plus platinum with fluoropyrimidine as first line treatment for unresectable ESCC patients. ATTRACTION-3 resulted in nivolumab approval for second line therapy of unresectable ESCC patients who have not been exposed to ICI. Here we provide a review of nivolumab and how this relates to ESCC management.

EXPERT OPINION

Some ESCC patients will not experience a response to ICIs. Determining intrinsic and acquired resistance patterns are needed to further capitalize on ICI therapy for ESCC patients. PD-L1 expression has been explored as a potential biomarker. Data shows, however, PD-L1 positive tumor patients benefit but this assessment is not always needed.

Clearance as an Early Indicator of Efficacy for Therapeutic Monoclonal Antibodies: Circumventing Dose Selection Challenges in Oncology

BACKGROUND AND OBJECTIVE

The designs of first-in-human (FIH) studies in oncology (e.g., 3 + 3 dose escalation design) usually do not provide a sufficient sample size to determine the dose-response relationship for efficacy. This study aimed to assess the feasibility of using monoclonal antibody (mAb) clearance as a biomarker for efficacy to facilitate the identification of potentially efficacious doses across cancer types and drug targets.

METHODS

We performed electronic searches of the Drugs@FDA website, the European Medicines Agency website, and PubMed to identify reports of FIH trials of approved mAbs in oncology. The clearance, half-life, and overall response rate (ORR) data for the mAbs at different dose levels were extracted.

RESULTS

Twenty-five approved mAbs were included in this study. As expected, due to the small sample sizes in FIH studies, there was no clear dose-response for ORR. However, we found a clear negative association between mAb clearance and ORR across tumors/drug targets, and a clear negative dose-clearance relationship, with clearance decreasing and saturated at high dose levels. The approved mAb doses (1-25 mg/kg) are approximately 2-fold the saturation doses (1-10 mg/kg). The associated clearance values at the approved doses vary across different cancers and drug targets (0.17-1.56 L/day), while tend to be similar within a disease/drug target. Anti-CD20 mAbs for B-cell lymphomas show a higher clearance (~ 1 L/day) than other cancers and targets (e.g., ~ 0.3 L/day for anti-PD-1).

CONCLUSIONS

Clearance of mAbs can be a tumor/drug target-agnostic biomarker for potential anti-tumor activity as clearance decreases with increasing ORR. Our findings shed important insights into target clearance values that may lead to desired efficacy for different cancers and drug targets, which can be used to guide dose selection for the future development of mAbs during FIH oncology studies.

Overcoming barriers to timely recognition and treatment of cancer cachexia: Sharing Progress in Cancer Care Task Force Position Paper and Call to Action

Cachexia is a life-threatening disorder affecting an estimated 50-80% of cancer patients. The loss of skeletal muscle mass in patients with cachexia is associated with an increased risk of anticancer treatment toxicity, surgical complications and reduced response. Despite international guidelines, the identification and management of cancer cachexia remains a significant unmet need owing in part to the lack of routine screening for malnutrition and suboptimal integration of nutrition and metabolic care into clinical oncology practice. In June 2020, Sharing Progress in Cancer Care (SPCC) convened a multidisciplinary task force of medical experts and patient advocates to examine the barriers preventing the timely recognition of cancer cachexia, and provide practical recommendations to improve clinical care. This position paper summarises the key points and highlights available resources to support the integration of structured nutrition care pathways.

Advances in pharmacokinetics and pharmacodynamics of PD-1/PD-L1 inhibitors

Immune checkpoint inhibitors (ICIs) are a group of drugs designed to improve the therapeutic effects on various types of malignant tumors. Irrespective of monotherapy or combinational therapies as first-line and later-line therapy, ICIs have achieved benefits for various tumors. Programmed cell death protein-1 (PD-1) / ligand 1 (PD-L1) is an immune checkpoint that suppresses antitumor immunity, especially in the tumor microenvironment (TME). PD-1/PD-L1 immune checkpoint inhibitors block tumor-related downregulation of the immune system, thereby enhancing antitumor immunity. In comparison with traditional small-molecule drugs, ICIs exhibit pharmacokinetic characteristics owing to their high molecular weight. Furthermore, different types of ICIs exhibit different pharmacodynamic characteristics. Hence, ICIs have been approved for different indications by the Food and Drug Administration (FDA) and National Medical Products Administration (NMPA). This review summarizes pharmacokinetic and pharmacodynamic studies of PD-1/ PD-L1 inhibitors to provide a reference for rational clinical application.

Population Pharmacokinetics of Nivolumab in Japanese Patients with Nonsmall Cell Lung Cancer

BACKGROUND

Nivolumab is an antiprogrammed death-1 (PD-1) antibody used for immuno-oncological therapy of various cancers, including nonsmall cell lung cancer (NSCLC). This study aimed to characterize the real-world population pharmacokinetics (PK) of nivolumab in patients with NSCLC.

METHODS

PK samples were collected by opportunistic sampling of Japanese patients with NSCLC treated with nivolumab monotherapy. Population PK analysis was performed using a two-compartment model in Nonlinear Mixed Effect Model. Patient-specific factors such as body weight, age, sex, serum albumin, estimated glomerular filtration rate, performance status, programmed cell death receptor ligand 1 expression in tumors, and treatment periods were evaluated as potential covariates for clearance.

RESULTS

A total of 223 serum samples collected from 34 patients were available for analysis. The median (min-max) age and weight were 69 years (38-83 years) and 62.7 kg (36.8-80.5 kg), respectively. The mean (95% confidence interval) clearance estimate was 0.0064 L/h (0.0058-0.0070 L/h). The inclusion of the ALB level, estimated glomerular filtration rate, and treatment period significantly improved the model fit.

CONCLUSIONS

A real-world nivolumab population PK model was developed using an opportunistic sampling strategy in Japanese patients with NSCLC. Further studies are warranted to characterize the exposure-response relationship and determine the optimal dosing regimens for these patients.

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.

Receptor occupancy assessment and interpretation in terms of quantitative systems pharmacology: nivolumab case study

Receptor occupancy assays applied in clinical studies provide insights into pharmacokinetic-pharmacodynamic relationships for therapeutic antibodies. When measured by different assays, however, receptor occupancy results can be controversial, as was observed for nivolumab, a monoclonal antibody targeting programmed cell death 1 (PD-1) receptor. We suggested an explanation of results obtained and a mechanistic approach based on specific features of the receptor occupancy assays: measurement of the free or bound receptor, normalized to the baseline or at each time point. The approach was evaluated against controversial clinical data on PD-1 receptor occupancy by nivolumab. It was shown that receptor occupancy measured by different assays might vary substantially if the internalization rate of the bound receptor is higher than the rate of degradation of the free receptor. Equations proposed in this work can be applied in quantitative systems pharmacology models to describe target receptor occupancy by different therapeutic antibodies.