BackgroundThis proof-of-concept retrospective case study investigated whether patient-reported outcomes (PRO) instruments, designed to capture symptomatic adverse event data, could identity a known exposure-response (ER) relationship for safety characterized in an original FDA analysis of an approved anti-cancer agent. PRO instruments have been designed to uniquely quantify the tolerability aspects of exposure-associated symptomatic adverse events. We explored whether standard ER analyses of clinician-reported safety data for symptomatic adverse events could be complemented by ER analysis using PRO data that capture and quantify the tolerability aspects of these same symptomatic adverse events.MethodsExposure-associated adverse event data for diarrhea were analyzed in parallel in 120 patients enrolled in a clinical trial using physician reported Common Terminology Criteria for Adverse Events (CTCAE) and patient-reported symptomatic adverse event data captured by the National Cancer Institute's (NCI) PRO Common Terminology Criteria for Adverse Events (PRO-CTCAE) instrument. Comparative ER analyses of diarrhea were conducted using the same dataset. Results from the CTCAE and PRO-CTCAE ER analyses were assessed for consistency with the ER relationship for diarrhea established in the original NDA using a 750-patient dataset. The analysis was limited to the 120-patient subset with parallel CTCAE and PRO-CTCAE assessments.ResultsWithin the same 120-patient dataset, ER analysis using dense, longitudinal PRO-CTCAE-derived data was sensitive to identify the known ER relationship for diarrhea, whereas the standard CTCAE based ER analysis was not.ConclusionsER analysis using PRO assessed symptomatic adverse event data may be a sensitive tool to complement traditional ER analysis. Improved identification of relationships for safety, by including quantification of the tolerability aspect of symptomatic adverse events using PRO instruments, may be useful to improve the sensitivity of exposure response analysis to support early clinical trial dosage optimization strategies, where decision making occurs within limited small patient datasets.

In this chapter, we describe the importance of bioanalytical methods to drug development. These assays, measuring the active drug and metabolites, provide critical information on the exposure of the drug that is used to correlate with safety and efficacy data to demonstrate the appropriate selection of the dosage strength and frequency. Technologies discussed include those supporting small molecule drugs (chromatographic assays (LC-MS/MS)), biologics (immunoassays), and gene therapies (polymerase chain reaction assays (PCR)). This chapter reviews the predominant technologies and critical features in their use to provide reliable data, the characteristics of the assays that must be demonstrated during validation, and case studies highlighting many of these aspects.

The authors regret the original funding statement in this article was incorrect. The funding statement should read as follows: “This work was supported by the Mayo Clinic Breast Cancer Specialized Program of Research Excellence Grant (P50CA 116201). Dr. Goetz is the Erivan K. Haub Family Professor of Cancer Research Honoring Richard F. Emslander, M.D.” The authors would like to apologise for any inconvenience caused. Bringing safe and effective therapies to premenopausal women with breast cancer: efforts to broaden eligibility criteriaAnnals of OncologyVol. 32Issue 8PreviewIn 2020, there were more than 276 480 estimated new cases of and 42 690 deaths from breast cancer in the United States overall, with a rising incidence in younger patients.1-3 Safe and effective treatments for premenopausal women with breast cancer remain an area of unmet medical need. To encourage inclusion of premenopausal women in breast cancer clinical trials, the Food and Drug Administration (FDA) released a new draft guidance document entitled ‘Premenopausal Women with Breast Cancer: Developing Drugs for Treatment’, on 7 October 2020. Full-Text PDF Open Archive

Abstract BACKGROUND: Renal impairment (RI) is a common complication in patients with multiple myeloma (MM). Effective myeloma treatment can lead to reduction in urinary light-chain excretion and reversibility of RI. Our pooled analysis assessed the magnitude of improvement in renal function (RF) in patients with newly diagnosed (ND) or relapsed and/or refractory (RR) MM treated with novel agent induction therapies, including 3 immunomodulators, 3 proteasome inhibitors, 1 histone deacetylase inhibitor, 1 XP01 inhibitor and 2 monoclonal antibodies. METHODS: Seventeen registrational trials with 34 treatment arms that collected time profiles of RF during treatment with novel agent induction therapies in 3569 patients with NDMM and 7786 patients with RRMM at baseline were identified from various new drug applications submitted to the US FDA. Change in estimated glomerular filtration rate (eGFR, as estimated by Modification of Diet in Renal Disease formula) compared to baseline was summarized for each therapy. RESULTS: Increase in eGFR was observed in patients with MM and each category of RI (mild [eGFR 60 - <90 mL/min/1.73 m2], moderate [eGFR 30 - <60 mL/min/1.73 m2] or severe [eGFR 15 - <30 mL/min/1.73 m2]) at baseline who received induction therapies. The time to greatest improvement in eGFR was approximately 3 to 6 months post-treatment. The average improvement in eGFR between Month 3 and 6 post-treatment, as compared to baseline, is summarized in Table 1 for each therapy. Further analysis showed that patients with clinical objective responses (partial response or better) tended to have greater improvement in eGFR than non-responders, especially in patients with NDMM. Table 1:Improvement in eGFR in patients with MM and RI during the treatment of novel agent induction therapies between Month 3 and 6 as compared to baseline.PatientsTherapyMean (SD) increase in eGFR (mL/min/1.73 m2)% of patients with improvement in eGFR by at least 1 categoryRRMM (N=7786)Monotherapy A8.8 (15.3)33%Monotherapy B-1.5 (10.4)10%Monotherapy C5.9 (13.9)25%Combination D7.7 (15.4)30%Combination E8.9 (17.2)30%Combination F8.1 (14.9)33%Combination G7.6 (14.6)28%Combination H9.5 (16.1)34%Combination I6.5 (14.0)28%Combination J7.4 (14.6)27%Combination K7.6 (14.8)28%Combination L6.4 (12.0)17%Combination M3.1 (14.5)13%Combination N11.2 (17.1)38%NDMM (N-3569)Combination D7.8 (16.4)32%Combination J7.6 (16.0)29%Combination O6.0 (15.2)28%Combination P10.1 (16.7)38%Combination Q10.4 (17.5)37%Combination R11.5 (17.7)38% CONCLUSIONS: During the treatment with novel agent induction therapies for MM, frequent assessment of RF is needed in patients with RI to guide the proper dosing regimen. Citation Format: Liang Li, Shuai Hu, Hao Zhu, Yaning Wang, Lian Ma, Brian P. Booth, Nam Atiqur Rahman, Janice Schwartz, Gideon Blumenthal, Qi Liu. Improvement in renal function in patients with multiple myeloma and impaired renal function receiving novel agent induction therapies [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 587.

The microsampling workshop generated recommendations pertaining to blood sampling site (venous blood versus capillary blood), when to conduct a bridging study, statistical approaches to establish correlation/concordance and deciding on sample size, opportunities and challenges with patient-centric sampling, and how microsampling technology can enrich clinical drug development. Overall, the goal was to provide clarity and recommendations and enable the broader adoption of microsampling supporting patients’ needs, convenience, and the transformation from clinic-centric to patient-centric drug development. The need and adoption of away-from-clinic sampling techniques has become critical to maintain patient safety during the current COVID-19 pandemic.

In the near-term, the wide-spread use of hybrid assays appears to be 'the ne-t big thing' in bioanalysis as evidenced by its inclusion in recent professional publications (Table 1) and discussions at scientific meetings. Consequently, the US FDA has been prompted to issue guidance/specifications/e-pectations for hybrid assays; however, regulatory e-perience with these modalities has been e-tremely scarce to date. Much of the interest in FDA guidance has been for acceptance criteria around accuracy and precision for hybrid assays. Several authors have privately and publicly promulgated the use of the ligand-binding assay (LBA) criteria (20/25%) because of the use of LBA to enrich the samples [1]. The FDA has not stated a position on this issue yet [2], due to the lack of data in regulatory submissions, but it has indicated that those criteria would be based on the data generated over time. However, review of the recent literature (Table 1) tends to indicate overwhelmingly that chromatographic acceptance criteria are easily met. So, with data like these, chromatographic acceptance criteria would seem to be the more reasonable choice. The typical validation parameters in and of themselves are not the issues of greatest interest. This combinatorial approach of a hybrid assay, and the inclusion of a digestion step is much more comple-than the average assay for either a small-molecule drug, measured by LC-MS or therapeutic protein assayed by LBA. Consequently, the FDA has questions about these 'new' steps in the process and how they affect reliability of the assay.

Pembrolizumab is a monoclonal antibody that targets the programmed death-1 receptor to induce immune-mediated clearance (CL) of tumor cells. Originally approved by the US Food and Drug Administration in 2014 for treating patients with unresectable or metastatic melanoma, pembrolizumab is now also used to treat patients with non-small-cell lung cancer, classical Hodgkin lymphoma, head and neck cancer, and urothelial cancer. This paper describes the recently identified feature of pembrolizumab pharmacokinetics, the time-dependent or time-varying CL. Overall results indicate that CL decreases over the treatment period of a typical patient in a pattern well described by a sigmoidal function of time with three parameters: the maximum proportion change in CL from baseline (approximately Imax or exactly eImax − 1), the time to reach Imax/2 (TI50), and a Hill coefficient. Best overall response per response evaluation criteria in solid tumor category was found to be associated with the magnitude of Imax.

Exposure-response (E-R) analyses for ado-trastuzumab emtansine (T-DM1, Kadcyla) were performed using data from a randomized, active control (lapatinib plus capecitabine) trial in patients with human epidermal growth factor 2-positive metastatic breast cancer. Kaplan-Meier survival analyses stratified by T-DM1 trough concentration on day 21 of cycle 1 (Cmin,C1D21) were performed for overall survival (OS) and progression-free survival (PFS). E-R analyses indicated that after adjusting for baseline risk factors, higher T-DM1 exposure is associated with improved efficacy. T-DM1-treated patients with Cmin,C1D21 lower than the median value had values of OS and PFS comparable to those of the active control arm. The percentage of patients who received T-DM1 dose adjustments was similar across the exposure range and was lower than that of the active control arm. Our findings suggest that there may be an opportunity to optimize Kadcyla dose in the patient subgroup with low T-DM1 exposure for improved efficacy with acceptable tolerability.

In the 2012 AAPS metabolites in safety testing (MIST) symposium held in Chicago, IL, USA, on October 15, 2012, regulatory experts and industrial scientists joined together to discuss their perspectives and strategies in addressing contemporary MIST recommendations (FDA 2008, International Conference on Harmonization (ICH) M3(R2), ICH M(R2) Q&A). Overall, these regulatory guidances indicate that metabolites identified in human plasma should circulate at similar or greater concentrations in at least one of the animal species used in nonclinical safety assessment of the parent drug. However, synthetic standards for the metabolites often do not exist or they are intractable to synthesize, thus introducing multiple challenges in drug development for the quantitative comparison of metabolites between human and animals. A tiered bioanalytical strategy for metabolite analysis is a prevalent approach to demonstrate coverage in animals. Recent developments in bioanalytical methodology have yielded several time- and resource-sparing strategies to provide fit-for-purpose approaches that can enable critical decisions related to metabolite quantification and monitoring in plasma. This report summarizes the presentations and panel discussions at the symposium.

ABSTRACT Background Rivaroxaban is an oral Factor Xa inhibitor. The primary objective of this communication was to quantitatively predict changes in rivaroxaban exposure when individuals with varying degrees of renal impairment are co‐administered with another drug that is both a P‐gp and a moderate CYP3A4 inhibitor. Methods A physiologically based pharmacokinetic (PBPK) model was developed to simulate rivaroxaban pharmacokinetics in young (20–45 years) or older (55–65 years) subjects with normal renal function, mild, moderate and severe renal impairment, with or without concomitant use of the combined P‐gp and moderate CYP3A4 inhibitor, erythromycin. Results The simulations indicate that combined factors (i.e., renal impairment and the use of erythromycin) have a greater impact on rivaroxaban exposure than expected when the impact of these factors are considered individually. Compared with normal young subjects taking rivaroxaban, concurrent mild, moderate or severe renal impairment plus erythromycin resulted in 1.9‐, 2.4‐ or 2.6‐fold increase in exposure, respectively in young subjects; and 2.5‐, 2.9‐ or 3.0‐fold increase in exposure in older subjects. Conclusions These simulations suggest that a drug–drug–disease interaction is possible, which may significantly increase rivaroxaban exposure and increase bleeding risk. These simulations render more mechanistic insights as to the possible outcomes and allow one to reach a decision to add cautionary language to the approved product labeling for rivaroxaban. Copyright © 2012 John Wiley & Sons, Ltd.

This University of Wisconsin School of Pharmacy bioanalytical conference is presented each year by the Extension Services in Pharmacy, the professional development department within the School. The purpose of this 4-day conference is to provide an educational forum to discuss issues and applications associated with the analysis of xenobiotics, metabolites, biologics and biomarkers in biological matrices. The conference is designed to include and encourage an open exchange of scientific and methodological applications for bioanalysis. To increase the interactive nature of the conference, the program was a mixture of lectures, poster sessions, round table discussions and workshops. This article summarizes the presentations at the 13th Annual Conference.

In this issue of Bioanalysis we have focussed on incurred sample reanalysis, with the aim of providing some examples of incurred sample reanalysis failures and ensuing investigations, to provide a greater shared experience.

9550 Background: On October 29, 2010 the US FDA granted accelerated approval for the use of everolimus in the treatment of patients with SEGA associated with TS not amenable to curative surgical resection. Data from a single-arm trial (N=28 patients) was submitted for patients treated with a starting dose of 3 mg/m2/day of everolimus and subsequently titrated to a target steady-state blood trough concentration (Cminss) of 5-15 ng/ml. An exposure-response analysis of the results was conducted to examine whether: Everolimus demonstrates activity in SEGA, and; therapeutic window (5-15 ng/ml) is appropriate. METHODS Exposure-response analysis focused on the relationship between average Cminss within a patient during 6 months (exposure) and percent reduction from baseline SEGA tumor volume at six months (response). The distribution of Cminss along with the % of patients within the 5-15 ng/ml target range was also examined to explore appropriateness of therapeutic window. RESULTS Exposure (Cminss) data were divided into quartiles (n=7 patients per quartile). An increased response was observed with increased average Cminss with no additional increase in response for Cminss ≥ 3 ng/ml. Increase in response with increase in exposure indicates that the drug elicited a pharmacological effect. The exposure-response relationship results support the lower limit of everolimus target trough concentration of 5 ng/ml, as clinical response was observed at 3 ng/ml. However, the upper limit of 15 ng/ml was not supported by these results. Only 21-44% of the patients were within the target range with most of the patients having Cminss <5 ng/ml. Only 6 patients demonstrated concentrations that exceeded 10 ng/ml. Consequently, the safety profile at higher exposures remains unknown. Furthermore, since no additional reduction in tumor volume was observed at Cminss ≥3 ng/ml, therapeutic window was revised to 5-10 ng/ml in the everolimus labeling. CONCLUSIONS The observed exposure-response relationship provided supportive evidence for anti-tumor activity of everolimus in the treatment of SEGA and a rationale for 5-10 ng/ml therapeutic window.

2597 Background: FDA drug approval requires demonstrated efficacy in adequate, well-controlled trials. In oncology, two key questions should be asked prior to initiation of “pivotal” efficacy trials: 1) which patient subsets should be enrolled into efficacy trials; and 2) what dose(s) should be tested? Improved phase 1 (P1) trials may help answer these questions and maximize likelihood for success in later development. We developed a knowledge management (KM) tool to aid FDA scientists in amassing a database of P1 trial characteristics, with the intention of developing standardized regulatory advice for future oncology drug development. Methods: We evaluated medical literature and investigational new drug (IND) P1 protocols submitted to FDA to determine key elements for database development. We then convened a panel of FDA clinical oncologists, pharmacologists, and pharmacogeneticists to determine what data should be captured to 1) allow comparisons of early drug development features for successful and unsuccessful development programs; and 2) inform future regulatory policy. Results: The KM tool was devised to capture information that could signal whether enrichment strategies should be considered or differential drug responses could be expected in later trials. In addition, the searchable database captures key elements from early phase oncology trials such as: a) molecule type and mechanism of action for targeted or non-targeted agents; b) molecular alterations known to associate with disease or drug target; c) PD assessment in tumor and surrogate tissues; d) molecularly- or clinically-enriched dose escalation and expansion cohorts; e) availability of a molecular test to select patients most likely to benefit from therapy; f) dosing schedule; g) dose escalation method and protocol-defined escalation endpoint; h) dose-limiting toxicity; i) observed responses; and j) recommended vs. actual phase 2 doses. Conclusions: P1 trials are important in helping guide drug development. We developed the first regulatory database of P1 trial design features to serve as a source for comprehensive assessment of early oncology drug development programs, which may be used for future policy development.

4087 Background: In 2010, the FDA approved Herceptin (trastuzumab) as treatment for HER2-overexpressing metastatic gastric cancer. The purpose of this analysis was to further evaluate whether the a...

The 5th Workshop on Recent Issues in Bioanalysis (WRIB) was organized by the Calibration and Validation Group as a 2-day full immersion workshop for pharmaceutical companies, CROs and regulatory agencies to discuss, review, share perspectives, provide potential solutions and agree upon a consistent approach to recent issues in the bioanalysis of both small and large molecules. High quality, better compliance to regulations and scientific excellence are the foundation of this workshop. As in the previous editions of this significant event, recommendations were made and a consensus was reached among panelists and attendees, including industry leaders and regulatory experts representing the global bioanalytical community, on many 'hot' topics in bioanalysis. This 2011 White Paper is based on the conclusions from this workshop, and aims to provide a practical reference guide on those topics.

2601 Background: For many drugs, impaired renal function (RF) may alter pharmacokinetics (PK) to an extent requiring dosage adjustment. The CG is commonly utilized in approved product labeling (PI), but the MDRD is also used in clinical practice. The purpose of this study was to assess the relationship between the CG and MDRD equations to predict RF and concordance in the dose modification for oncology-related drugs. Methods: Demographic and pertinent laboratory data (presented as percentage [%] or median [25th, 75th percentile]) was pooled from renal dosing studies submitted to FDA in support 7 oncology related drugs. Four of these drugs ultimately required dose modification for renal impairment in the PI. Creatinine clearance (Clcr) and glomerular filtration rate (GFR) was estimated using the CG and MDRD equations, respectively. The relationship between these two estimates was determined by correlation analysis and a comparison of estimated RF to PK drug exposures for the 7 drugs. Additionally, the agreement between the recommended dosing was assessed for both estimates in determining dosing modifications in the PI of 4 oncology related drugs (lenalidomide [L], peginterferon alfa-2b [PG], pemetrexed [P], and zoledronic acid [Z]). Results: Individual RF estimates were calculated from 493 research subjects (serum creatinine 1.1 mg/dL (0.8, 1.7); race (82% Caucasian, 13% Black); body weight 77.7 kg (65.9, 92.1)). Correlation analysis of CG and MDRD estimates showed r2=0.69 (p<0.0001) for all observations and r2=0.8 (p<0.0001) when RF estimates > 80 mL/min were excluded. Both estimates appeared to have similar correlation with the PK exposure. The same renal dosing modification was made for L, PG, P and Z 83%, 85%, 82% and 81% of the time, respectively. Where recommendations did not agree, CG estimates resulted in a one step higher dose in 2/3 of the disagreements. Conclusions: There is an adequate relationship between CG and MDRD estimates of RF and both achieve reasonably similar renal dosing modifications in the drugs studied. No significant financial relationships to disclose.

The 3rd Calibration and Validation Group Workshop on Recent Issues in Regulated Bioanalysis was organized by the Calibration and Validation Group as a 1.5-day full immersion workshop for contract research organizations, pharmaceutical companies and regulatory agencies to discuss several ‘hot’ topics concerning bioanalytical issues and regulatory challenges. A consensus was reached among panelists and attendees on many points regarding method validation of small molecules.

The 4th Calibration and Validation Group Workshop on Recent Issues in Regulated Bioanalysis, a 2-day full immersion workshop, was organized by the Calibration and Validation Group. Contract research organizations, pharmaceutical companies and regulatory agencies came together to discuss several 'hot' topics concerning bioanalytical issues and regulatory challenges and to reach a consensus among panelists and attendees on many points regarding method validation of small and large molecules.