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The purpose of this overview was to perform an exploratory analysis of in‐house drug‐drug interaction (DDI) studies conducted with investigational drugs and oral midazolam to assess the value of measuring 1‐OH‐midazolam (1‐OHM) in such studies. The perpetrator effect of the investigational drugs on cytochrome P450 3A (CYP3A) was assessed by analyzing both midazolam and 1‐OHM in plasma and evaluating their pharmacokinetic parameters. Given the almost exclusive metabolism of the parent drug by CYP3A to the main metabolite 1‐OHM, an increase in midazolam and a decrease in 1‐OHM exposure in the case of CYP3A inhibition caused by a perpetrator drug would be expected. The opposite would be anticipated in the case of CYP3A induction. For this analysis, the perpetrator potential of eight different investigational drugs was incorporated. Among the 10 studies included, the identified CYP3A inhibitors (n = 4) and inducers (n = 1) were classified based on the data generated with midazolam per se, with 1‐OHM levels not contributing to the interpretation of the data as they did not corroborate the findings of the parent compound. Therefore, it was concluded that continued analysis of 1‐OHM in plasma may be questionable as it does not add value to the interpretation of the results when performing CYP3A DDI studies with an investigational drug as a perpetrator. [ABSTRACT FROM AUTHOR]

Patients with psoriasis often take multiple medications due to comorbidities, raising concerns about drug–drug interactions (DDIs) during the development of new medicines. DDI risk assessments of a new small molecule showed risks of CYP3A4 autoinduction and being a sensitive CYP3A4 substrate. We conducted a real‐world evidence (RWE) claims analysis to assess the frequency of prescription claims for up to 12 months from the date of the initial psoriasis diagnosis for drugs that may interact with CYP3A4 substrates. We used 2013 to 2018 patient data from the US Merative MarketScan Research Database. Among patients diagnosed with psoriasis, less than 1% had a claim for a moderate/strong inducer, but up to 15% had a claim for moderate/strong inhibitor. Most prescriptions for CYP3A4 inhibitors or inducers included antibiotics and anticonvulsants. While CYP3A4 inducers were rarely used, those treated received more than >90 days treatment. Then, these RWE data were used to inform the early translational medicine strategy for the new investigational drug by strategically integrating DDI evaluations into a first‐in‐human healthy volunteer trial prior to studies in patients with psoriasis. The resulting DDI substudy showed that the investigational small molecule did not induce midazolam clearance but was sensitive to CYP3A inhibition, leading to the decision to exclude concomitant use of strong CYP3A4 inducers or inhibitors from clinical trials. [ABSTRACT FROM AUTHOR]

Firsocostat is an oral, liver‐targeted inhibitor of acetyl‐coenzyme A carboxylase in development for the treatment of metabolic dysfunction‐associated steatohepatitis. Hepatic organic anion transporting polypeptides play a significant role in the disposition of firsocostat with minimal contributions from uridine diphospho‐glucuronosyltransferase and cytochrome P450 3A enzymes. This phase 1 study evaluated the pharmacokinetics and safety of firsocostat in participants with mild, moderate, or severe hepatic impairment. Participants with stable mild, moderate, or severe hepatic impairment (Child–Pugh A, B, or C, respectively [n = 10 per cohort]) and healthy matched controls with normal hepatic function (n = 10 per cohort) received a single oral dose of firsocostat (20 mg for mild and moderate hepatic impairment; 5 mg for severe hepatic impairment) with intensive pharmacokinetic sampling over 96 h. Safety was monitored throughout the study. Firsocostat plasma exposure (AUCinf) was 83%, 8.7‐fold, and 30‐fold higher in participants with mild, moderate, and severe hepatic impairment, respectively, relative to matched controls. Firsocostat was generally well tolerated, and all reported adverse events were mild in nature. Dose adjustment is not necessary for the administration of firsocostat in patients with mild hepatic impairment. However, based on the observed increases in firsocostat exposure, dose adjustment should be considered for patients with moderate or severe hepatic impairment, and additional safety and efficacy data from future clinical trials will further inform dose adjustment. [ABSTRACT FROM AUTHOR]

The current regulatory path for new drug registration in East Asian countries has led to significant delay of the new medicines in these countries. A unified regulatory path and allowance of mutual usage of clinical data in East Asian countries would lead to cost saving in drug development and expedite the new drug registration in these countries. The objectives of the present analysis are to compare the approval dates of a selection of products developed by Pfizer in the United States and East Asian countries (China, Japan, Korea) and compare the pharmacokinetics and recommended doses of these products in East Asian countries. Eighteen products (20 drugs, 2 products with 2 combination drugs) with exposure data available in at least 2 of the 3 East Asian countries across different therapeutic areas were included in the analyses. The results showed that most products had delayed approval in East Asian countries (up to 8 years) after US or EU approval. No distinct differences were observed in the drug exposure and recommended doses for the selected products in East Asian countries. These results together with literature data of genetic similarity of the East Asian populations support the mutual usage of the clinical data in the East Asian countries for expedited regulatory submission and approval. [ABSTRACT FROM AUTHOR]

The prevalence of obesity has grown tremendously in recent years and this population has an increased risk of disease comorbidities. The presence of disease comorbidities requires treatment interventions and proper dosing guidelines. However, drug development programs often do not have adequate representation of individuals who are obese in clinical trials, leaving gaps in the understanding of treatment response leading to a lack of adequate individualization options. Based on a recent survey of approved drug product package inserts, very few approved products included specific dosing based on obesity, in both adults and pediatrics. Reasons for the limited information on patients who are obese may include the under‐reporting of information regarding such patients and a lack of clinical trial diversity in enrolling patient groups in whom obesity or obesity‐related comorbidities are more prevalent. An inadvertent impact of the practice of exclusion of subsets of patients with some comorbidities in clinical trials may play a role in the reduced enrollment of individuals who are obese. Recently, regulatory authorities have taken specific initiatives to promote clinical trial diversity, including engaging with stakeholders and publishing regulatory guidance. These guidance documents highlight the need to enroll diverse clinical trial populations and provide recommendations on concepts related to drug development for obese populations. Such efforts will help to address the gap in information regarding drug response and dosing in patients who are obese. [ABSTRACT FROM AUTHOR]

Since 2015, concentration–QTc (C–QTc) analysis has been used to exclude the possibility that a drug has a concerning effect on the QTc interval. This has enabled the replacement of the designated thorough QT (TQT) study with serial electrocardiograms (ECGs) in routine clinical pharmacology studies, such as the first‐in‐human (FIH) study. The E14 revision has led to an increased proportion of FIH studies with the added objective of QT evaluation, with the intention of replacing the TQT study. With the more recent revision of the S7B/E14 Q&A document in February 2022, nonclinical assays/studies can be brought into the process of regulatory decisions at the time of marketing application. If the hERG (human ether‐a‐go‐go‐related gene) and the non‐rodent in vivo study are conducted according to the described best practices and are negative, the previous requirement that a QTc effect of >10 milliseconds must be excluded in healthy subjects at plasma concentrations 2‐fold above what can be seen in patients can be reduced to covering the concentrations seen in patients. For drugs that cannot be safely given in high doses to healthy subjects, ECG evaluation is often performed at the therapeutic dose in patients. If a QTc effect of >10 milliseconds can be excluded, an argument can be made that the drug should be considered as having a low likelihood of proarrhythmic effects due to delayedrepolarization, if supported by negative best practices hERG and in vivo studies. In this article, we describe what clinicians involved in early clinical development need to understand in terms of the hERG and in vivo studies to determine whether these meet best practices and therefore can be used in an integrated clinical/nonclinical QT/QTc risk assessment. [ABSTRACT FROM AUTHOR]

Pregnant people have traditionally been excluded from therapeutic research by restrictions intended for fetal protection. Despite a movement toward inclusion, concerns for the feasibility and safety of including pregnant people in studies continue to limit this research. This article reviews the history of research guidelines in pregnancy and illustrates ongoing challenges, as seen in the development of vaccines and therapies during the coronavirus disease 2019 pandemic and investigation of statins for preeclampsia prevention. It explores new approaches that may be used to improve therapeutic research in pregnancy. A major cultural shift is needed to balance potential maternal and/or fetal risks with potential benefits from participation in research, as well as harm from withholding treatment or providing one that is not evidence‐based. Finally, it is important to honor maternal autonomy in decision‐making regarding participation in clinical trials. [ABSTRACT FROM AUTHOR]

Many of the conditions for the safe and effective use of new molecular entities (NMEs) are understood at the time of initial drug approval. However, some remaining knowledge gaps can be addressed after drug approval through postmarketing requirements (PMRs) or commitments (PMCs) established by the US Food and Drug Administration (FDA). Our objective was to conduct an assessment of clinical pharmacology–related PMRs and PMCs established at the time of approval and evaluate the impact of fulfilled PMRs and PMCs on prescription information (PI). This analysis included clinical pharmacology–related PMRs and PMCs established for NMEs approved between 2009 and 2020. Of the 1171 PMRs and PMCs, over one‐third were clinical pharmacology–related. Of these, 46% were to evaluate drug interactions, 16% were to evaluate drug dosing in patients with hepatic impairment, and 10% were related to dose. The majority (57%) of PMRs and PMCs were fulfilled at the time of analysis, with a median time to fulfillment of approximately 2.3 years. The majority (94%) of the fulfilled PMRs and PMCs, either with or without a PI revision, resulted in new or modified instructions for use or supported existing instructions for use. This is the first time that clinical pharmacology–related PMRs and PMCs have been catalogued and analyzed to understand their impact on PI. An understanding of the knowledge gaps that exist at the time of drug approval could inform the most effective and efficient methods for evidence generation prior to and after new drug approval. [ABSTRACT FROM AUTHOR]

Rare diseases are frequently caused by inherited 'monogenic' defects. Treatment interventions that target a specific genetic location or that replaces a specific protein provide rational therapeutic approaches. The current review discusses innovative targeted therapies that act or modulate at the level of DNA, RNA, or protein. They include DNA gene editing, small interference RNA (siRNA), antisense oligonucleotide (ASO), small molecule RNA splicing modifier, and bispecific antibody. With limited numbers of patients, testing multiple dose levels and regimens prior to making an informed dose decision remains one of the major challenges in rare disease drug development. Clinical pharmacology strategically bridges the gap to support drug development and regulatory approvals. Pharmacokinetic drug exposures are driven by absorption, distribution, metabolism, elimination, and in some cases immunogenicity. Drug responses are measured by pharmacodynamic biomarkers that are linked to either short‐ or long‐term clinical outcomes. Understanding the drug exposure–response relationship lies at the heart of bridging the gap that enables a dose decision by balancing effectiveness and safety. Furthermore, and importantly, understanding the influence of intrinsic and extrinsic factors on drug pharmacokinetics enables dose adjustment decisions based on drug exposures. Case examples include the identification of doses and regimens without a formal dose‐finding study, the support of new doses and regimens without conducting additional studies, and the extrapolation of adult drug–drug interaction (DDI) studies to pediatrics without performing a pediatric DDI study. With increasing discoveries of innovative treatment modalities, the responsibility of clinical pharmacologists is expected to grow and enhance the development of novel treatments for rare diseases. [ABSTRACT FROM AUTHOR]

The article provides information on the use of medications during pregnancy and the lack of clinical data on their safety and efficacy in pregnant populations. It discusses the historical events that shaped drug regulation and research involving pregnant women. There is a call for earlier inclusion of pregnant patients in clinical trials and the need for curated information to ensure their access to safe and effective therapeutics.

The article presents the discussion on considerable progress in the development of the COVID-19 vaccines. Topics include primary immunization led to considerably improving the protection against the omicron variant; and no significant difference in clinical data between bebtelovimab alone comparing with the combination of bebtelovimab with other monoclonal antibodies.

Felcisetrag (formerly known as TAK‐954) is a selective serotonin receptor agonist under investigation for use in patients with postoperative gastrointestinal dysfunction. The safety, tolerability, and pharmacokinetics (PK) of intravenous (i.v.) felcisetrag have been studied, but little is known about the effect of hepatic impairment on the PK of the drug. This phase 1, non‐randomized, open‐label study compared the PK of a single 60‐minute i.v. infusion of felcisetrag between healthy individuals (n = 8) and patients with moderate (n = 10) or severe (n = 7) hepatic impairment. The primary study end points were the total and free maximum observed plasma concentration of felcisetrag at the end of infusion (Cmax), area under the concentration–time curve (AUC) from time 0 to the time of the last quantifiable concentration (AUClast), and AUC from time 0 to infinity (AUCinf). Concentration–time profiles of felcisetrag were similarly shaped between groups but revealed lower concentrations of total plasma felcisetrag with increasing severity of hepatic impairment, whereas concentrations of free felcisetrag increased. The ratios of AUClast and AUCinf for patients with severe hepatic impairment were up to 29.3% lower for total felcisetrag and up to 29.2% higher for free felcisetrag than found in healthy individuals (P <.05). Infusions were well tolerated with no discontinuations, severe adverse events, or deaths during the study. Overall, the effect of hepatic impairment on exposure to felcisetrag was minimal, suggesting that dose adjustment may be unnecessary in patients with hepatic impairment. [ABSTRACT FROM AUTHOR]

The use of placebo concurrent control (placebo‐controlled) is the most rigorous method of evaluating the safety and efficacy of investigational treatments. However, the use of a placebo group in pediatric product development can be challenging due to ethical considerations and potential differences in placebo response rates between adults and children. This study reports the US Food and Drug Administration's experience with placebo response rates in the pediatric population. Products studied under the Best Pharmaceuticals for Children Act and the Pediatric Research Equity Act between 2012 and 2020 were screened. Study characteristics including study type, primary efficacy endpoint(s), placebo response rates for the primary efficacy endpoint(s) and studied age range were collected. A total of 71 drug products used a placebo‐controlled trial. Of these, thirteen products had an identical study design and trial characteristics including the primary efficacy endpoints between pediatric and adult studies. Fifteen products were studied in trials with identical study design but only different primary efficacy endpoints in pediatric and adult populations. Ten products had combined adolescent and adult trials with separate pediatric trials in younger age groups. In each of these cases, the pediatric placebo response was greater, for some trials, and less, for other trials, than the adult placebo response. The pediatric placebo response can vary within an age group for a drug product. Future studies should examine the factors leading to a similarity or dissimilarity in placebo response between pediatric patients and adults. [ABSTRACT FROM AUTHOR]

The "drug lag" (ie, the approval lag for new drugs) hinders patients' access to innovative new medicines. The drug lag was heavily debated in Japan from the late 2000s to the early 2010s. It consists of "development lag" (ie, the submission date lag for new drug applications) and "review lag" (ie, the difference in review periods). As the 2 lags have different causes and display significantly different recent trends in Japan, we focus on the development lag—in contrast with most previous literature—between Japan and the United States, based on a database we created for all new drugs from 2008 to 2018 using publicly available data sources. First, we found that Japan's development lag relative to the United States did not shrink in terms of the overall distribution rather than the median, which was the focus of most prior studies. Second, we examined the factors (product characteristics) that significantly affected the development lag and found that products that underwent multiregional clinical trials and those that were certified as "breakthrough therapies" in the United States had significantly shorter development lags with high robustness, whereas products receiving price premiums did not. Finally, we discussed the policy implications of these results. For instance, innovative new drugs that are presumed to receive price premiums require enhanced policy support for early application from the initial stages of clinical trials. It is also essential to promote information sharing regarding evaluations by foreign reviewing authorities for efficient use in the home country. [ABSTRACT FROM AUTHOR]

Tropifexor, a non–bile acid farnesoid X receptor (FXR) agonist, has dose‐proportional pharmacokinetics and no obvious major enterohepatic circulation. This open‐label study investigated the effect of hepatic impairment (HI), as determined by Child‐Pugh grade, on tropifexor's pharmacokinetics, safety, and tolerability following a 200‐μg dose in the fasted state. Blood samples were collected through 168 hours after dosing for quantification and plasma protein‐binding determination. Total tropifexor exposure was comparable across participants with HI vs those with normal hepatic function. Tropifexor was highly protein bound (>99%) in human plasma across participants of all groups. The average unbound fractions (percentage free) were 0.14% in participants with normal hepatic function and mild HI, which increased to 0.17% and 0.24% in participants with moderate and severe HI, respectively. Similar unbound drug exposure was noted in participants with mild HI and normal hepatic function. Participants with moderate HI (N = 8) had a 1.6‐fold increase in unbound exposure (area under the plasma concentration–time curve from time 0 to infinity [AUCinf,u]) and a 1.3‐fold increase in maximal exposure (Cmax,u) vs those with normal hepatic function (geometric mean ratio: AUCinf,u, 1.64 [90%CI, 1.25‐2.16]; Cmax,u, 1.30 [90%CI, 0.96‐1.76]). Participants with severe HI (N = 8) had a 1.6‐fold increase in AUCinf,u (1.61 [90%CI, 1.04‐2.49]) and comparable Cmax,u (1.02 [90%CI, 0.60‐1.72]) compared to participants with normal hepatic function. Tropifexor was well tolerated. The relative insensitivity of tropifexor to HI offers the potential to treat patients with severe liver disease without dose adjustment. [ABSTRACT FROM AUTHOR]

The article informs that companies seeking Food and Drug Administration (FDA) approval for their medical products are dramatically shifting human research overseas. It mentions FDA must use the funds solely for mutually agreed upon functions, predominantly speeding the pace of product approvals; and also mentions clinical trials offer the assessment of the efficacy and safety of new medical products.

MK‐8507 is an investigational HIV‐1 nonnucleoside reverse transcriptase inhibitor being developed for the treatment of HIV‐1 infection. MK‐8507 contains 2 trifluoromethyl groups that may result in fluoride release through metabolism, but the extent of MK‐8507–related fluoride release in humans has yet to be determined. This double‐blind, placebo‐controlled, 2‐period, parallel‐group, multiple‐dose trial in healthy participants without HIV‐1 who were administered a fluoride‐restricted diet and once‐weekly doses of MK‐8507 aimed to estimate the relationship between MK‐8507 dose and fluoride exposure. A total of 15 adult male and 3 adult female (of non‐childbearing potential) participants were randomized to receive MK‐8507 200 mg (n = 6), MK‐8507 800 mg (n = 6), or placebo (n = 6). Change from baseline in mean daily fluoride excretion averaged over 7 days following the administration of MK‐8507 200 mg resulted in a net mean increase of 19.8 μmol (90% confidence interval, 12.2‐27.4) relative to placebo and did not exceed 57 μmol, a threshold related to the mean difference between the daily reference dose set by the US Environmental Protection Agency and the average dietary fluoride intake in the United States. However, daily urinary fluoride excretion exceeded the threshold following administration of 800 mg MK‐8507 (75.1 μmol [90% confidence interval, 67.5‐82.7]). Assuming a linear relationship between MK‐8507 dose and estimated mean daily fluoride released at steady‐state, data interpolation suggests that the US Environmental Protection Agency reference dose for fluoride would not be exceeded in most patients when administering MK‐8507 at doses currently under clinical investigation (≤400 mg once weekly). [ABSTRACT FROM AUTHOR]

Ipatasertib is a selective AKT kinase inhibitor currently in development for the treatment of several solid tumors, including breast and prostate cancers. This study was undertaken to characterize pharmacokinetic profiles of ipatasertib and its metabolite M1 (G‐037720) and to understand the sources of variability. Population pharmacokinetic models of ipatasertib and M1 were developed separately using data from 342 individuals with cancer from 5 phase 1 and 2 studies. The final population pharmacokinetic models for ipatasertib and M1 were 3‐compartmental, with first‐order elimination and sequential zero‐ and first‐order absorption. Ipatasertib bioavailability and M1 formation increased after multiple dosing, resulting in an increase in exposure beyond that expected from accumulation alone. Covariate effects of ipatasertib include decreased oral clearance with increasing age and with coadministration of abiraterone, as well as decreased bioavailability with increasing weight. For ages 37 and 80 years, steady‐state area under the curve (AUCss) was predicted to be 81% and 109%, respectively, of the typical population value (64 years). For body weight of 49 and 111 kg, AUCss was predicted to be 132% and 78%, respectively, of the typical population value (75 kg). The small magnitude of change in ipatasertib exposure is not likely to be clinically relevant. For M1, the peripheral distribution volume and intercompartmental clearance increased with increasing weight. Coadministration of abiraterone was estimated to increase M1 exposure by 61% at steady state. Mild and moderate renal impairment, mild hepatic impairment, and race were not identified as significant covariates in the final models for ipatasertib and M1. [ABSTRACT FROM AUTHOR]

This analysis compared the results from noncompartmental analysis and population pharmacokinetic (PopPK) predictions of exposure changes in patients with renal impairment (RI) for 27 new molecular entities (NMEs) approved between 2000 and 2015. Renal function was identified as a covariate in the final PopPK model for 17 NMEs. The final PopPK model was used to simulate (n = 1000 replicates/individual) the results of a dedicated PK study in subjects with renal impairment. For the majority of NMEs, concordance between observed, and predicted area under the curve (AUC) geometric mean ratio (GMR) was observed (ie, in 17, 11, and 11 NMEs for mild, moderate, and severe renal impairment groups, respectively, the observed and predicted AUC GMR were within the same fold of change). Inclusion of colinear covariates in the PopPK model appeared to be the major driver for the NMEs for which there was discordance. PopPK, when done properly, is a valuable tool for supporting labeling recommendations for subjects with renal impairment. [ABSTRACT FROM AUTHOR]

The article discusses new era of fetal clinical pharmacology including understanding drug disposition and effect in the fetus will come in several stages. Topics include the exposure of the fetus to drugs be labeled as one of the most neglected areas of drug development and clinical pharmacology; new era of fetal clinical pharmacology including understanding drug disposition and effect in the fetus will come in several stages.

Tezepelumab is a human monoclonal antibody that blocks thymic stromal lymphopoietin, an epithelial cytokine involved in asthma pathogenesis. In the phase 2b PATHWAY study (ClinicalTrials.gov identifier: NCT02054130), tezepelumab significantly reduced exacerbations in adults with severe, uncontrolled asthma. We used pharmacokinetic (PK) and pharmacodynamic (PD) modeling to guide tezepelumab dose selection for phase 3 trials in patients with severe asthma. PK data from 7 clinical studies were used to develop a population PK model. Population PK‐PD models were developed to characterize the relationship between tezepelumab PK and asthma exacerbation rate (AER) and fractional exhaled nitric oxide (FeNO) levels (using phase 2b PD data only). Tezepelumab PK were well described by a 2‐compartment model with first‐order absorption; PK parameter estimates were consistent with those of other immunoglobulin G2 antibodies. PK‐PD models predicted that subcutaneous dosing at 210 mg every 4 weeks was associated with ≈90% of the maximum drug effect of tezepelumab on AER and FeNO; further dose increases were not expected to result in additional, clinically meaningful treatment benefit. No clinically significant covariates of treatment effects on AER and FeNO were identified. Population PK simulations, exposure‐response relationships and safety profiles of tezepelumab at doses up to 280 mg every 2 weeks suggested that no dose adjustment based on body weight or for adolescents was required. These results support the selection of 210 mg every 4 weeks subcutaneously as the dose for phase 3 studies of tezepelumab in adults and adolescents with severe asthma. [ABSTRACT FROM AUTHOR]

The use of extrapolation of efficacy in pediatric drug development programs is possible when disease progression and treatment response are similar in adult and pediatric populations. Historically, the exposure‐response (E‐R) similarity was assessed by visual inspection of 2 E‐R curves to support pediatric extrapolation. The aim of this study was to develop a quantitative framework to describe the E‐R relationship and the difference in E‐R between pediatric and adult patients based on accumulated experience in pediatric drug development programs. Using clinical data for 8 drugs with either a linear or nonlinear E‐R relationship, we adapted the methodology used in noninferiority testing to assess the E‐R similarity between adult and pediatric patients at the targeted drug exposure. We implemented bootstrap‐based and Bayesian‐based methodologies to estimate the probability of concluding noninferiority of the E‐R relationship. This approach provides objective criteria that can be applied to an assessment of E‐R noninferiority in 2 populations to support extrapolation of efficacy in drug development programs from adults to pediatric populations. [ABSTRACT FROM AUTHOR]

We report the population pharmacokinetic (PK) and exposure‐response analyses of a novel subcutaneous formulation of daratumumab (DARA) using data from 3 DARA subcutaneous monotherapy studies (PAVO Part 2, MMY1008, COLUMBA) and 1 combination therapy study (PLEIADES). Results were based on 5159 PK samples from 742 patients (DARA 1800 mg subcutaneously, n = 487 [monotherapy, n = 288; combination therapy, n = 199]; DARA 16 mg/kg intravenously, n = 255 [all monotherapy, in COLUMBA]; age, 33‐92 years; weight, 28.6‐147.6 kg). Subcutaneous and intravenous DARA monotherapies were administered once every week for cycles 1‐2, once every 2 weeks for cycles 3‐6, and once every 4 weeks thereafter (1 cycle is 28 days). The subcutaneous DARA combination therapy was administered with the adaptation of corresponding standard‐of‐care regimens. PK samples were collected between cycle 1 and cycle 12. Among monotherapy studies, throughout the treatment period, subcutaneous DARA provided similar/slightly higher trough concentrations (Ctrough) versus intravenous DARA, with lower maximum concentrations and smaller peak‐to‐trough fluctuations. The PK profile was consistent between subcutaneous DARA monotherapy and combination therapies. The exposure‐response relationship between daratumumab PK and efficacy or safety end points was similar for subcutaneous and intravenous DARA. Although the ≤65‐kg subgroup reported a higher incidence of neutropenia, no relationship was found between the incidence of neutropenia and exposure, which was attributed, in part, to the preexisting imbalance in neutropenia between subcutaneous DARA (45.5%) and intravenous DARA (19%) in patients ≤50 kg. A flat relationship was observed between body weight and any grade and at least grade 3 infections. The results support the DARA 1800‐mg subcutaneous flat dose as an alternative to the approved intravenous DARA 16 mg/kg. [ABSTRACT FROM AUTHOR]

CD33 is a transmembrane protein that is found on cells of myeloid lineage. It is also intensely expressed on acute myeloid leukemia (AML) progenitor cells but not on normal stem cells. It internalizes on binding and dimerization, making it a specific and ideal target for AML therapeutics and drug delivery. Several targeted therapies have been tested and many are still currently in development. Gemtuzumab ozogamicin was the first and only CD33‐directed antibody‐drug conjugate to be US Food and Drug Administration approved for AML. Other targeted agents have not achieved such success. Promising new strategies include cellular therapy mechanisms and linker molecules. This is an exciting target that requires a considerable amount of precision to yield clinical benefit. [ABSTRACT FROM AUTHOR]

Antibody‐drug conjugates are important molecular entities in the treatment of cancer, with 8 antibody‐drug conjugates approved by the US Food and Drug Administration since 2000 and many more in early‐ and late‐stage clinical development. These conjugates combine the target specificity of monoclonal antibodies with the potent anticancer activity of small‐molecule therapeutics. The complex structure of antibody‐drug conjugates poses unique challenges to pharmacokinetic (PK) and pharmacodynamic (PD) characterization because it requires a quantitative understanding of the PK and PD properties of multiple different molecular species (eg, conjugate, total antibody, and unconjugated payload) in different tissues. Quantitative clinical pharmacology using mathematical modeling and simulation provides an excellent approach to overcome these challenges, as it can simultaneously integrate the disposition, PK, and PD of antibody‐drug conjugates and their components in a quantitative manner. In this review, we highlight diverse quantitative clinical pharmacology approaches, ranging from system models (eg, physiologically based pharmacokinetic [PBPK] modeling) to mechanistic and empirical models (eg, population PK/PD modeling for single or multiple analytes, exposure‐response modeling, platform modeling by pooling data across multiple antibody‐drug conjugates). The impact of these PBPK and PK/PD models to provide insights into clinical dosing justification and inform drug development decisions is also highlighted. [ABSTRACT FROM AUTHOR]

Currently, the world is facing the pandemic of a novel strain of beta‐coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Acute respiratory distress syndrome (ARDS) is the most devastating complication of SARS‐CoV‐2. It was indicated that cytokine‐release syndrome and dominantly interleukin (IL)‐6 play a central role in the pathophysiology of ARDS related to the novel 2019 coronavirus disease (COVID‐19). Despite the global emergency of the disease, at this time, there are no proven therapies for the management of the disease. Tocilizumab is a potential recombinant monoclonal antibody against IL‐6 and currently is under investigation for the management of ARDS in patients with COVID‐19. Given these points, we reviewed the current evidence regarding the potential therapeutic role of tocilizumab and its important clinical issues in the treatment of ARDS related to COVID‐19. [ABSTRACT FROM AUTHOR]

This open label, parallel‐group study investigated the pharmacokinetics and safety of a single oral 2‐mg dose of the novel selective progesterone receptor modulator vilaprisan in participants with impaired renal function compared with age, weight, sex, and race matched controls with normal renal function. Systemic exposure (area under the plasma concentration–time curve [AUC]) and maximum observed concentrations (Cmax) were compared among 9 participants with moderate renal impairment and matched controls by ANOVA. An additional 4 participants, each with severe renal impairment or normal renal function, contributed to a linear regression analysis exploring any monotone relationship between individual variables and the estimated glomerular filtration rate. The geometric mean AUC was increased by a factor of 1.35 in renally impaired participants compared to normal controls (not statistically significant: least squares mean, 1.346; 90% confidence interval, 0.918‐1.973). Cmax was similar in participants with moderate renal impairment and normal renal function (least squares mean, 1.026; 90% confidence interval, 0.779‐1.351). Considering the overall variability, there was no correlation between renal function (estimated glomerular filtration rate) and Cmax or AUC of vilaprisan. Single oral administration of vilaprisan 2 mg was well tolerated by all participants, both men and women and irrespective of renal function. The incidence of treatment‐emergent adverse events was similar across all groups. Results from this study do not indicate that a dose adjustment will be necessary for vilaprisan when treating patients up to moderate renal impairment. [ABSTRACT FROM AUTHOR]

The article focuses on hydroxychloroquine and azithromycin to tread patients with COVID-19. Topics inlcude the world is facing a frightening pandemic due to COVID-19 has caused, the severe acute respiratory syndrome coronavirus 2 with thousands of severe infections and fatalities, and the hydroxychloroquine being cheap and readily available decades-old drug with immunomodulatory properties used to treat autoimmune rheumatic diseases.

Despite agreement that early‐onset schizophrenia is continuous with the adult‐onset form, quantitative relationships between antipsychotic exposure and clinical response are relatively unexplored in adolescents, compared to adults. Clinical efficacy data from second‐generation antipsychotic development programs (N = 5951 adults and N = 1035 adolescents ranging from 12 to 17 years old) were collected from available new drug applications submitted to the US Food and Drug Administration from 1993 to 2017. The developed disease–drug trial models adequately predicted the longitudinal trend in total positive and negative syndrome scale scores in both adults and adolescents using a Weibull placebo response, time‐delayed drug effect, and a Weibull structural dropout model. Maximum drug effect was similar between the two populations and was estimated to be between a range of 5% to 11% in adults and 5% to 7% in adolescents. Half maximal effective concentration parameter estimates also indicated similar exposure‐response relationships in adults and adolescents across all 4 antipsychotics. Simulated adolescent data using final model parameter estimates from the adult model were in agreement with adolescent observations. This analysis confirms similarity in exposure‐response for efficacy and could expedite the development of second‐generation antipsychotics for adolescents. [ABSTRACT FROM AUTHOR]

Nemolizumab is a humanized anti-interleukin-31 receptor A monoclonal antibody for treating atopic dermatitis, and it especially improves pruritus. The objective of the simulation study was to optimize the dose regimen using a flat dose. The serum nemolizumab concentration and pruritus visual analog scale as an efficacy end point were modeled using the population analysis approach in 299 patients with atopic dermatitis who received placebo or doses between 0.1 and 3 mg/kg as a single dose once every 4 weeks or 2 mg/kg once every 8 weeks. A 1-compartment model with first-order absorption was employed as the pharmacokinetic model. An indirect turnover model with an inhibition component was employed as the main part of the pharmacokinetic-pharmacodynamic model. The models well described the observations. Therefore, simulations with several dose regimens were performed to optimize the dose regimen including a flat dose. The simulated area under the concentration-time curve at a steady state around 75 mg in the every-4-week regimen corresponds to that associated with the dose range of 0.5 to 2 mg/kg in the 4-week regimen. The simulated pruritus visual analog scale also showed a similar tendency. These simulation results support dose optimization during the clinical development program of nemolizumab. [ABSTRACT FROM AUTHOR]

Global trial (GT) strategy and bridging (BG) strategy are currently the main clinical development strategies of oncology drugs in Japan, but the relationship between development style and drug lag and how the bridging strategy has contributed to the solution of drug lag have not been clear. We investigated the potential factors that influenced submission lag (SL), and also compared the differences in SL among early-initiation BG strategy, late-initiation BG strategy, and GT strategy. A stepwise linear regression analysis identified the potential factors that shorten SL: development start lag and development style. Comparison of the differences in SL among the strategies also indicated that the SL in the GT strategy and that in the early-initiation BG strategy were significantly shorter than that in the late-initiation BG strategy. The findings in our study suggest that the late-initiation BG strategy may not contribute to shortening drug lag. Because the number of late-initiation BG studies has not decreased, we propose first that pharmaceutical companies should initiate clinical development as early as possible in Japan so that they can choose the GT strategy as a first option at the next step, and second when they cannot choose the GT strategy after investigating differences in exposure between Japanese and non-Japanese in a phase 1 study, they should select the early BG strategy to avoid future drug lag. It is also important for the regulatory authorities to provide reasonable guidance to have a positive impact on strategic decisions, even for foreign-capital companies. [ABSTRACT FROM AUTHOR]

In this review of individual patient expanded-access requests to the Center for Drug Evaluation and Research for the period Fiscal Year 2010 to Fiscal Year 2014, we evaluated the number of applications received and the number allowed to proceed. We also evaluated whether drugs and certain biologics obtained under expanded access went on to be approved by the Food and Drug Administration. Finally, we considered concerns that adverse events occurring during expanded access might place sponsors at risk for legal liability. Overall, 98% of individual patient expanded-access requests were allowed to proceed. During the study period, among drugs without a previous approval for any indication or dosage form, 24% of unique drugs (ie, multiple applications for access to the same drug were considered to relate to 1 unique drug), and 20% of expanded-access applications received marketing approval by 1 year after initial submission; 43% and 33%, respectively, were approved by 5 years after initial submission. A search of 3 legal databases and a database of news articles did not appear to identify any product liability cases arising from the use of a product in expanded access. Our analyses seek to give physicians and patients a realistic perspective on the likelihood of a drug's approval as well as certain information regarding the product liability risks for commercial sponsors when providing expanded access to investigational drugs. The US Food and Drug Administration (FDA)'s expanded-access program maintains a careful balance between authorizing patient access to potentially beneficial drugs and protecting them from drugs that may have unknown risks. At the same time, the agency wishes to maintain the integrity of the clinical trials process, ultimately the best way to get safe and effective drugs to patients. [ABSTRACT FROM AUTHOR]

Generally, licensed drug-dosing recommendations for chemotherapy are based on results from clinical trials in which subjects are usually of relatively normal body size, middle-aged, and are relatively racially homogeneous, with minimal comorbidity and specific tumor characteristics. Very few nontrial patients meet these characteristics, resulting in clinical practice having to extrapolate dosing recommendations to the specific patient. There is insufficient research on the impact of obesity-associated physiological changes prevalent in patients with common cancers on standard pharmacokinetic and pharmacodynamic parameters. Yet quantifying the influence of obesity on the pharmacology of chemotherapy is vital, as dosing inappropriate for body composition (ie, flat dosing or mg/kg based on total body weight) may increase the risk of adverse events and reduce clinical effectiveness. Unfortunately, there are few cancer guidelines to aid clinicians in selecting the optimal dose in the obese-even recent guidelines are based predominantly on clinical opinion/current practice in treating obese patients, rather than evidence. Data in many other vulnerable groups, for example, those with significant comorbidity and older patients, are also scarce. Because of the known limitations of body surface area-guided dosing, therapeutic drug monitoring or pharmacokinetic-guided dosing, which predicts an individual's exposure, has increasingly been shown to be a powerful tool in cancer therapy. Used appropriately, it can adjust for differences in pharmacokinetic parameters not considered when body size-based dosing or 'one dose fits all' is used. This review will focus predominantly on the rationale for pharmacokinetic-guided dosing of the newer oral molecularly targeted antineoplastics in people whose drug exposure is not predicted by their physiology or body composition. [ABSTRACT FROM AUTHOR]

Rivipansel is a pan-selectin inhibitor in phase 3 development for the treatment of vaso-occlusive crises in patients with sickle cell disease. This single-dose, randomized, 3-period, 3-treatment (400 mg moxifloxacin open-label, 4 g rivipansel-blinded, and placebo-blinded) crossover study evaluated the effect of rivipansel on the QT/QTc interval in 48 healthy male African American subjects (age, 21-53 years; weight, 60-115 kg). Time-matched, placebo-adjusted change from baseline QT interval using Fridericia's correction method (QTcF) was determined using a repeated-measures mixed-effects model. The highest upper bound of the 2-sided 90% confidence interval (CI) for QTcF change was 3.22 milliseconds 3 hours postdose. Moxifloxacin showed the anticipated QTcF effect, indicating that the study had adequate sensitivity to detect changes in the QTcF interval. The study concluded that no QTcF effect was demonstrated with rivipansel compared with placebo, as the upper bound of the 2-sided 90%CI was less than 10 milliseconds at all times. Exposure-response modeling for rivipansel concentrations and change from baseline in QTcF data corroborated a lack of effect with rivipansel compared with placebo. Single doses of rivipansel 4 g by intravenous infusion over 20 minutes were well tolerated in this study. [ABSTRACT FROM AUTHOR]

DS-3801b is an orally active, nonmacrolide, selective motilin receptor agonist. The aim of this 2-part first-in-human study was to assess the safety, tolerability, pharmacokinetics, and pharmacodynamic effects on proximal and distal gastrointestinal (GI) motility of single oral doses of DS-3801b in healthy subjects. The 13C-octanoate breath test was used to assess gastric emptying (GE), a measure of proximal GI motility. The time to first bowel movement (TTFBM) and the consistency of the first bowel movement according to the Bristol Stool Scale (BSS) were recorded to assess distal GI motility. In part A, 48 subjects received single oral doses of DS-3801b from 1 to 100 mg or placebo (6 DS-3801b, 2 placebo per cohort). In part B, 12 subjects received 50 mg of DS-3801b or placebo to assess GE. DS-3801b is safe and generally well tolerated after doses up to 50 mg, resulting in mild, predominantly GI adverse events. DS-3801a plasma concentrations increase with increasing doses; however, Cmax increases greater than dose-proportionally, whereas AUC increases less than dose-proportionally. The double peaks observed are consistent with multiple absorption sites. Results of the 13C-octanoate breath test indicate that DS-3801b accelerates GE. Fifty milligrams of DS-3801b resulted in a 20.8% median reduction in GE T1/2 and a 20.6% median reduction in GE Tlag compared with placebo. However, this increase in proximal GI motility was not accompanied by an effect on distal GI motility, as indicated by no significant differences in TTFBM and BSS values across DS-3801b dose levels or compared with placebo. [ABSTRACT FROM AUTHOR]

In the pivotal TEMPO 3:4 trial, the arginine vasopressin V2-receptor antagonist tolvaptan reduced the rate of kidney growth in patients with autosomal dominant polycystic kidney disease. Tolvaptan was initiated as daily morning/afternoon doses of 45/15 mg, and uptitrated weekly to 60/30 mg and 90/30 mg according to patient-reported tolerability. The current report describes 3 phase 2 trials in adult autosomal dominant polycystic kidney disease subjects that were the basis for the titrated split-dose regimen: a single ascending-dose trial (tolvaptan 15 to 120 mg; n = 11), a multiple split-dose trial (tolvaptan 15/15 mg, 30/0 mg, 30/15 mg, and 30/30 mg; n = 37), and an 8-week open-label safety and efficacy trial in 46 of the 48 subjects who participated in the prior 2 trials (tolvaptan 30/15 mg, 45/15 mg, 60/30 mg, and 90/30 mg). Urine osmolality (Uosm) was chosen as the biomarker of V2 receptor inhibition. Two tolvaptan doses per day were necessary to suppress Uosm to <300 mOsm/kg for 24 hours. The 45/15-mg regimen was well tolerated and effective in suppressing Uosm in >50% of subjects. Therefore, this regimen was selected as the starting regimen for the TEMPO 3:4 trial. The 90/30-mg regimen suppressed Uosm in 85% of subjects tested; however, only 28/46 subjects agreed to uptitrate to 90/30 mg due to tolerability. Higher concentrations of tolvaptan were less well tolerated, resulting in adverse events of pollakiuria, thirst, polyuria, nocturia, and a higher number of times out of bed to urinate. Subjects who agreed to uptitrate to 90/30 mg had lower eGFR than those who did not uptitrate. [ABSTRACT FROM AUTHOR]

The spleen tyrosine kinase (SYK) regulates immune cell activation in response to engagement of a variety of receptors, making it an intriguing target for the treatment of inflammatory and autoimmune disorders as well as certain B-cell malignancies. We have previously reported on the discovery and preclinical characterization of PRT062607, a potent and highly selective inhibitor of SYK that exhibits robust anti-inflammatory activity in a variety of animal models. Here we present data from our first human studies aimed at characterizing the pharmacokinetics (PK), pharmacodynamics (PD), and safety of PRT062607 in healthy volunteers following single and multiple oral administrations. PRT062607 demonstrated a favorable PK profile and the ability to completely inhibit SYK activity in multiple whole-blood assays. The PD half-life in the more sensitive assays was approximately 24 hours and returned to predose levels by 72 hours. Selectivity for SYK was observed at all dose levels tested. Analysis of the PK/PD relationship indicated an IC50 of 324 nM for inhibition of B-cell antigen receptor-mediated B-cell activation and 205 nM for inhibition of FcεRI-mediated basophil degranulation. PRT062607 was safe and well tolerated across the entire range of doses. Clinical PK/PD was related to in vivo anti-inflammatory activity of PRT062607 in the rat collagen-induced arthritis model, which predicts that therapeutic concentrations may be safely achieved in humans for the treatment of autoimmune disease. PRT062607 has a desirable PK profile and is capable of safely, potently, and selectively suppressing SYK kinase function in humans following once-daily oral dosing. [ABSTRACT FROM AUTHOR]

The pharmacokinetics (PK) and pharmacodynamics (PD) of omarigliptin, a novel once-weekly DPP-4 inhibitor, were assessed following single and multiple doses in healthy subjects. Absorption was rapid, and food did not influence single-dose PK. Accumulation was minimal, and steady state was reached after 2 to 3 weeks. Weekly (area under the curve) AUC and Cmax displayed dose proportionality within the dose range studied at steady state. The average renal clearance of omarigliptin was ∼2 L/h. DPP-4 inhibition ranged from ∼77% to 89% at 168 hours following the last of 3 once-weekly doses over the dose range studied. Omarigliptin resulted in ∼2-fold increases in weighted average postprandial active GLP-1. Omarigliptin acts by stabilizing active GLP-1, which is consistent with its mechanism of action as a DPP-4 inhibitor. Administration of omarigliptin was generally well tolerated in healthy subjects, and both the PK and PD profiles support once-weekly dosing. A model-based assessment of QTc interval risk from the single ascending dose study predicted a low risk of QTc prolongation within the likely clinical dose range, a finding later confirmed in a thorough QT trial. [ABSTRACT FROM AUTHOR]

During drug development, matching adult systemic exposures of drugs is a common approach for dose selection in pediatric patients when efficacy is partially or fully extrapolated. This is a systematic review of approaches used for matching adult systemic exposures as the basis for dose selection in pediatric trials submitted to the US Food and Drug Administration (FDA) between 1998 and 2012. The trial design of pediatric pharmacokinetic (PK) studies and the pediatric and adult systemic exposure data were obtained from FDA publicly available databases containing reviews of pediatric trials. Exposure-matching approaches that were used as the basis for pediatric dose selection were reviewed. The PK data from the adult and pediatric populations were used to quantify exposure agreement between the 2 patient populations. The main measures were the pediatric PK studies' trial design elements and drug systemic exposures (adult and pediatric). There were 31 products (86 trials) with full or partial extrapolation of efficacy with an available PK assessment. Pediatric exposures had a range of mean Cmax and AUC ratios (pediatric/adult) of 0.63 to 4.19 and 0.36 to 3.60, respectively. Seven of the 86 trials (8.1%) had a predefined acceptance boundary used to match adult exposures. The key PK parameter was consistently predefined for antiviral and anti-infective products. Approaches to match exposure in children and adults varied across products. A consistent approach for systemic exposure matching and evaluating pediatric PK studies is needed to guide future pediatric trials. [ABSTRACT FROM AUTHOR]

Significant and reversible reductions in testosterone levels were observed with AZD4901 in both preclinical and clinical testing. A comprehensive population pharmacokinetic/pharmacodynamic (PK/PD) modeling of AZD4901 concentration and testosterone relationship from 3 phase 1 studies was performed using NONMEM to support dose selection for phase 2a development. A 2-compartment model with first-order absorption and first-order elimination best described AZD4901 PK. Circadian rhythm of baseline testosterone concentrations was well described by a cosine function. An indirect response model with inhibition of testosterone production was used to link the AZD4901 concentration to testosterone response. The AZD4901 concentration to yield 50% maximum testosterone suppression (IC50) was estimated to be 230 ng/mL. Based on simulations, following 40 mg twice daily (BID) treatment, the AZD4901 steady-state trough concentration will be much higher compared to 80 mg once daily (QD). The AZD4901 concentration time above IC50 after 40 mg BID is 84% of the time of the dosing interval compared to only 49% after 80 mg QD. The mean predicted testosterone concentrations at steady state are lower and overall less variable over 24 hours for 40 mg BID dosing compared to 80 mg QD dosing. Population PK and PK/PD analyses demonstrated that AZD4901 40 mg BID is a better dosing strategy to more consistently suppress testosterone during the entire dosing interval. Consequently, 40 mg BID dosing was suggested in a phase 2a trial in females with polycystic ovary syndrome, and the trial resulted in a positive outcome as shown by significant testosterone decrease compared to placebo. [ABSTRACT FROM AUTHOR]

The objectives of this report are to summarize the content and status of transporter-related postmarketing requirement (PMR)/postmarketing commitment (PMC) studies in new drug applications (NDAs) approved by the U.S. Food and Drug Administration (FDA) and to discuss the reasons for requesting such studies and the impact of PMR/PMC study results on labeling to guide the optimal use of the drugs. Multiple data sources were searched to collect information on transporter-related PMR/PMC studies between January 1999 and May 2015. A total of 40 transporter-related PMR/PMC study requests were issued for 35 NDAs. Among these PMR/PMC studies, 27 requested studies related to P-glycoprotein. As of May 31, 2015, 34 transporter-related PMR/PMC studies (85%) are considered 'fulfilled' (per the FDA's PMR/PMC website), and 22 (65%) resulted in labeling updates. The majority of the PMR/PMC studies are for drugs in the therapeutic areas of anti-infectives, oncology, and neurology. The results from PMR/PMC studies are important for dosing optimization and are often included in the updated labeling. Because a significant lag time is anticipated between drug approval and PMR/PMC fulfillment, NDA applicants are encouraged to include transporter-related assessments in clinical drug development programs for drug products. [ABSTRACT FROM AUTHOR]

The author offers information on return on investments from drug-to-drug interaction in clinical studies. He mentions of contribution of science of pharmacology in drug development including understanding of pharmacokinetics (PK) and pharmacodynamics (PD), and states the importance of drug-drug interaction (DDI) studies to a drug development program.

Piragliatin is a CYP3A substrate; its inactive metabolite M4, formed through cytosolic reductase, is reversibly metabolized back to piragliatin through CYP3A. The impact of concomitant CYP3A modifiers thus cannot be predicted. Drinking alcohol under fasting conditions is associated with a recognized glucose-lowering effect, which might be synergistic with piragliatin's hypoglycemic effect. Two exploratory studies were conducted to examine these potential interactions in type 2 diabetes (T2D) patients: 16 completed an open-label, sequential 2-way crossover, 2-arm (randomized to ketoconazole and rifampicin) CYP3A study; another 18 participated in a double-blind, placebo-controlled, randomized 3-way crossover ethanol study. Administration of piragliatin (100-mg single dose) resulted in a 32% Cmax and 44% area under the curve (AUC∞) increase in piragliatin exposure without affecting glucose AUC0-6h following ketoconazole (400 mg QD × 5 days); 30% Cmax and 72% AUC∞ decrease in piragliatin exposure with a 13% increase in glucose AUC0-6h following rifampicin (600 mg QD × 5 days); and, unexpectedly, a 32% Cmax and 23% AUC0-6h decrease (no change in AUC∞) in piragliatin exposure with a 13% increase in glucose AUC0-6h following alcohol (40-g single dose). In conclusion, a strong CYP3A modifier or concomitant alcohol could lead to a change in exposure to piragliatin with a potential alteration in glucose-lowering effect. [ABSTRACT FROM AUTHOR]

In 1998, the United States Food and Drug Administration (FDA) released the first guidance for industry regarding pharmacokinetic (PK) studies in renally impaired patients. This study aimed to determine if the FDA renal PK guidance influenced the frequency and rigor of renal studies conducted for new chemical entities (NCEs). FDA-approved package inserts (APIs) and clinical pharmacology review documents were analyzed for 194 NCEs approved from 1999 to 2010. Renal studies were conducted in 71.6% of NCEs approved from 1999 to 2010, a significant increase over the 56.3% conducted from 1996 to 1997 ( P = .0242). Renal studies were more likely to be completed in highly renally excreted drugs ( fe ≥ 30%) compared with drugs with low renal excretion, fe < 30% (89.6% vs 65.8%, P = .0015). PK studies to assess the impact of dialysis were conducted for 31.7% of NCEs that had a renal study: a greater proportion of high fe NCEs were studied (44.2% vs 26.0%, P = .0335). No significant change in frequency or rigor of PK studies was detected over time. The majority of NCEs (76.3%) with a renal study provided specific dosing recommendations in the API. The adoption of the 1998 FDA guidance has resulted in improved availability of PK and drug-dosing recommendations, particularly for high fe drugs. [ABSTRACT FROM AUTHOR]

Nonlinearities are frequently encountered in pharmacokinetics, and they can occur when 1 or more processes of absorption, distribution, metabolism, and excretion are saturable. One special source of nonlinearity that has been noticed recently is the saturable binding of the drug to a high-affinity-low-capacity target, a phenomenon known as target-mediated drug disposition (TMDD). Although TMDD can occur in both small-molecule compounds and large-molecule compounds, the latter has received much more attention because of its high prevalence. With the development of more potent small-molecule drugs acting on highly specific targets and the availability of increasingly sensitive analytical techniques, small-molecule compounds exhibiting TMDD have been increasingly reported in the past several years. ABT-384 is a small-molecule drug candidate that exhibited significant nonlinear pharmacokinetics, potentially imparted by TMDD, in a first-in-human clinical trial conducted in healthy volunteers. Compared with published small-molecule compounds exhibiting TMDD, ABT-384 pharmacokinetic characteristics are more consistent with TMDD. To expand current knowledge of TMDD of small-molecule compounds and increase awareness of this interesting and clinically important phenomenon, in this review the general features of small-molecule compounds exhibiting TMDD are highlighted, with ABT-384 provided as an example. [ABSTRACT FROM AUTHOR]

Selection of the first dose for neonates in clinical trials is very challenging. The objective of this analysis was to assess if a population pharmacokinetic (PK) model developed with data from infants to adults is predictive of neonatal clearance and to evaluate what age range of prior PK data is needed for informative modeling to predict neonate exposure. Two sources of pharmacokinetic data from 8 drugs were used to develop population models: (1) data from all patients > 2 years of age, and (2) data from all nonneonatal patients aged > 28 days. The prediction error based on the models using data from subjects > 2 years of age showed bias toward overprediction, with median average fold error (AFE) for CL predicted/CLobserved greater than 1.5. The bias for predicting neonatal PK was improved when using all prior PK data including infants as opposed to an assessment without infant PK data, with the median AFE 0.91. As an increased number of pediatric trials are conducted in neonates under the Food and Drug Administration Safety and Innovation Act, dose selection should be based on the best estimates of neonatal pharmacokinetics and pharmacodynamics prior to conducting efficacy and safety studies in neonates. [ABSTRACT FROM AUTHOR]

We report population pharmacokinetic, pharmacodynamic, and pharmacokinetic-safety analyses to support phase II/III dose/regimen selection of alisertib, a selective Aurora A kinase (AAK) inhibitor. Phase I studies in adult cancer patients evaluated dosing on Days 1-7 in 21-day cycles or Days 1-21 in 35-day cycles, with corresponding maximum tolerated doses of 50 mg twice daily (BID) and 50 mg QD, respectively. Population pharmacokinetic analyses supported dose- and time-linear pharmacokinetics without identification of clinically meaningful covariates. Exposurerelated increases in skin mitotic index and decreases in chromosomal alignment/spindle bipolarity in tumor mitotic cells confirmed AAK inhibition. Exposures in the 7-day schedule at or near 50 mg BID are expected to result in tumor AAK inhibition based on pharmacodynamic assessment in patient tumors. Exposure-safety analyses of data from patients receiving doses of 5-200 mg/day in the 7-day schedule support a low (~ 7%) predicted incidence of dose-limiting toxicity at 50 mg BID. Taken together, these analyses support a pharmacologically active and acceptably tolerated dose range of alisertib for future clinical development. [ABSTRACT FROM AUTHOR]

Fasting and postprandial hyperglucagonemia in type 2 diabetes mellitus (T2DM) patients cause excessive hepatic glucose production (HGP), suggesting that attenuation of hepatic glucagon action could be a therapeutic strategy for T2DM. In this study we evaluated the safety, tolerability, PK, and pharmacodynamics in healthy human volunteers of single and multiple doses (50-400 mg) ISIS 325568, a 2′-O-MOE antisense (ASO) developed to reduce hepatic glucagon receptor (GCGR) mRNA expression. In the multiple dose cohorts, treatment consisted of eight doses of ISIS 325568 or placebo over 6-weeks. Drug effects were assessed using serial fasting glucagon measurements and the glycemic response to a glucagon challenge at baseline and at the end of 6-week treatment. ISIS 325568 was not associated with clinically relevant changes. Dose-dependent predominantly mild injection site reactions were the most common side-effect. Active treatment caused a gradual increase in fasting glucagon levels and, compared to placebo, a significantly blunted glucagon-induced increase in plasma glucose AUC (24%, P<0.0001) and HGP (13%, P = 0.007) at the 400 mg/week dose. Six weeks treatment with ISIS 325568 in healthy volunteers attenuated glucagon-stimulated HGP and glucose excursions, supporting further evaluation of the GCGR antisense approach in patients with T2DM. [ABSTRACT FROM AUTHOR]

Anacetrapib is a cholesteryl ester transfer protein inhibitor in Phase III development. This double-blind, double-dummy, randomized, placebo- and active-comparator-controlled, 4-period, balanced crossover study evaluated the effects of anacetrapib (100 mg and 800 mg) on QTcF interval in healthy subjects. QTcF measurements were made up to 24 h following administration of single doses of anacetrapib 100 or 800 mg, moxifloxacin 400 mg, or placebo in the fed state. The primary hypothesis was supported if the 90% CI for the least squares (LS) mean differences between anacetrapib 800 mg and placebo in QTcF interval change from baseline were entirely <10 msec at every post-dose time point (1, 2, 2.5, 3, 4, 5, 6, 8, 12, and 24 h). The upper bounds of the 90% CIs for LS mean differences from placebo in changes from baseline in QTcF intervals for anacetrapib 100 and 800 mg were <5 msec at every time point. In conclusion, single doses of anacetrapib 100 and 800 mg do not prolong the QTcF interval to a clinically meaningful degree relative to placebo and are generally well tolerated in healthy subjects. [ABSTRACT FROM AUTHOR]

Dacomitinib is currently in development for the treatment of non-small cell lung cancer. Formation of the major circulating metabolite (PF-05199265) is mediated by cytochrome P450 (CYP) 2D6 and CYP2C9. This phase I, single fixed-sequence, two-period study evaluated the effect of paroxetine, a CYP2D6 inactivator, on dacomitinib pharmacokinetics in healthy volunteers who were extensive CYP2D6 metabolizers. Subjects received a single 45-mg dacomitinib dose alone and in combination with paroxetine (30 mg/day for 10 consecutive days, with dacomitinib administered on day 4) at steady-state levels. Blood samples were collected through 240 hours post-dacomitinib dosing. Dacomitinib exposure (area under the concentration-time curve from 0 to infinity; AUCinf) increased 37%; however a reduction in PF-05199265 AUCinf of approximately 90% was observed during the paroxetine treatment period. The maximum concentration of dacomitinib changed minimally. Adverse events reported with single-dose dacomitinib administered alone or in the presence of steady-state levels of paroxetine were mostly mild, and no serious adverse events were reported. While paroxetine significantly inhibited CYP2D6-mediated metabolism of a single dose of dacomitinib, the modest effect on dacomitinib exposure is unlikely to be clinically relevant when dacomitinib is given daily. Dose adjustment of dacomitinib may therefore not be required upon coadministration with a CYP2D6 inhibitor. [ABSTRACT FROM AUTHOR]