Clinical Pharmacology of Glucagon.

Glucagon was discovered about a hundred years ago and its role in health and disease is under continuous investigation. Glucagon is a counter regulatory hormone secreted by alpha cells of the pancreas in response to multiple stimuli. Although some of glucagon's actions and its clinical application have been described, clinical experience with glucagon has been historically overshadowed by that of insulin. To date, the role of glucagon's actions in pharmacotherapy has been under explored. Glucagon plays a considerable role as a hormonal regulator via its known actions on the liver. The rise in obesity and diabetes mellitus prevalence is bringing focus to glucagon's known physiological roles and possible clinical applications. Six glucagon products and a glucagon analog are approved for use in the United States. Clinical pharmacology studies provide crucial support of glucagon's actions as evident from comprehensive pharmacokinetics and pharmacodynamics evaluations in humans. Here, we briefly describe the established physiological role of glucagon in humans and its known relationship with disease. We later summarize the clinical pharmacology of available glucagon products with different routes of administration.

Attitudes on participation in clinical drug trials: A nationally representative survey of older adults with multimorbidity.

BACKGROUND: Older adults with multimorbidity are under-represented in clinical drug trials. Their inclusion will not increase unless they are willing and able to participate. Data on motivators and barriers to participation in trials of new medications of older adults with multimorbidity are needed. METHODS: Cross-sectional internet and telephone survey of a nationally representative sample of adults ≥65 years with ≥3 chronic conditions (NORC University of Chicago Amerispeak Panel) conducted from March-April, 2023 to determine motivators and barriers to drug trial participation, described graphically and using statistics. RESULTS: Surveyed 1318 (1142 Internet, 176 phone) with mean age 72.3 ± 6.3 (SD), 52% women; race: 83% White, 10% Black or African American, 5% Hispanic or Latino, 1.1% Asian; 4.4 ± 1.9 chronic conditions (of 16 queried), taking 7.5 ± 3.3 medications. Barriers included fear of side effects (48%), taking too many medications (44%), placebo (44%), mobility (33%), bathroom needs (25%), hearing (19%), eyesight (15%), video visits (33%; higher in women, Black or African-American respondents, and those ≥80 years). Sixty-five percent would join all in-person trials, 49% would join all-video trials. Travel >1 h was difficult for 66%, most difficult for women. Trust was a concern in 25% of Black respondents. Caregiving responsibilities or lack of time were not obstacles. Participants were most likely to consider a drug trial for a problem they have (63%) versus prevention (44%) and if invited by a physician (80%) or University healthcare system (58%). Getting better care was ranked very important (79%) followed by helping others (57%). CONCLUSIONS: Major concerns of older patients with multimorbidity about participation in drug trials are potential side effects, taking too many medicines, and video visits. Physicians have the greatest influence on decisions and in-person visits are preferred. Proposed changes in trial design to increase enrollment of under-represented older adults may not align with patient-reported preferences.

Participation of Older Adults in Clinical Trials for New Drug Applications and Biologics License Applications From 2010 Through 2019.

Importance: Older age may be accompanied by changes in the pharmacokinetics or pharmacodynamics or both of medications that can result in altered safety and efficacy profiles. Objective: To assess representation of older adults in clinical trials of new drug applications (NDAs) and biologics license applications (BLAs). Design, Setting, and Participants: This cross-sectional study analyzed US Food and Drug Administration (FDA) data for NDAs and BLAs approved from 2010 through 2019. Age distribution of clinical trial participants was compared with age distribution of the US population with the disease or disorder (prevalent population). Data were from adults enrolled in registration trials for depression, heart failure, insomnia, non-small cell lung cancer (NSCLC), nonvalvular atrial fibrillation (NVAF) stroke prevention, osteoporosis, and type 2 diabetes or adults sampled from US prevalent population in community-dwelling health data. Data were analyzed from November 2020 to February 2021. Exposures: Trial enrollment. Main Outcomes and Measures: Representativeness of trial populations was assessed by the participation to prevalence ratio (PPR) defined as the percentage of patients by age group among clinical trial participants to the percentage of patients by age group among US prevalent population. Results: Data from 166 clinical trials (229 558 participants) for 44 NDAs and BLAs were analyzed. The most consistent finding was the limited enrollment of the oldest age groups, namely those 75 years and above for type 2 diabetes and NSCLC, and 80 years and above for NVAF stroke prevention, insomnia, heart failure, and osteoporosis. Adults aged 60 to 74 years were enrolled in equal or greater proportion than the US prevalent population. Conclusions and Relevance: In this cross-sectional study, underrepresentation of the oldest adults existed during evaluation of new drugs and biologics, yet the older adults may represent significant proportions of the treatment population. Closing the representation gap between clinical trial enrollment and potential treatment populations is essential for safe and effective use of new drugs and biologics.

Roadmap to 2030 for Drug Evaluation in Older Adults.

Changes that accompany older age can alter the pharmacokinetics (PK), pharmacodynamics (PD), and likelihood of adverse effects (AEs) of a drug. However, older adults, especially the oldest or those with multiple chronic health conditions, polypharmacy, or frailty, are often under-represented in clinical trials of new drugs. Deficits in the current conduct of clinical evaluation of drugs for older adults and potential steps to fill those knowledge gaps are presented in this communication. The most important step is to increase clinical trial enrollment of older adults who are representative of the target treatment population. Unnecessary eligibility criteria should be eliminated. Physical and financial barriers to participation should be removed. Incentives could be created for inclusion of older adults. Enrollment goals should be established based on intended treatment indications, prevalence of the condition, and feasibility. Relevant clinical pharmacology data need to be obtained early enough to guide dosing and reduce risk for participation of older adults. Relevant PK and PD data as well as patient-centered outcomes should be measured during trials. Trial data should be analyzed for differences in PK, PD, effectiveness, and safety arising from differences in age or from the presence of conditions common in older adults. Postmarket evaluations with real-world evidence and drug labeling updates throughout the product lifecycle reflecting new knowledge are also needed. A comprehensive plan is needed to ensure adequate evaluation of the safety and effectiveness of drugs in older adults.

Implications of obesity for drug therapy: limitations and challenges.

Obesity has become a worldwide challenge with significant health and socioeconomic implications. One of the major implications is its impact on drug therapy. In order to gain a better understanding of this impact, we surveyed the regulatory guidances, the newly approved molecular entity drug products, and drug product labels in the Physician's Desk Reference. This review summarizes the findings of the survey along with the existing knowledge on pharmacokinetic and pharmacodynamic changes associated with obesity.

Geriatric drug evaluation: where are we now and where should we be in the future?

The older population is currently the fastest growing age group in the United States, and this trend is expected to continue for several decades. Older individuals, in general, have a higher disease burden compared with younger adults and are the major users of medications, yet premarketing drug clinical trials have often excluded them even for the drugs that have high utility in this age group. Extrapolation of clinical results from younger to older individuals does not provide adequate benefit-risk estimation, and the frequent need for dose adjustment in older patients from initially approved doses exemplifies the current lack of adequate clinical data in the elderly. Herein, we discuss the information gap for older individuals and the need for a better understanding of the effect of aging on drug responses. We also present cases for future directions, urging the implementation of improved clinical trial designs using new and emerging pharmacokinetic and pharmacodynamic methods to allow the provision of evidence-based individualized treatment to this high drug use group.

Simultaneous determination of physostigmine and tetrahydroaminoacridine in a transdermal permeation study by high-performance liquid chromatography.

A selective and stability-indicating high-performance liquid chromatographic assay with diazepam as the internal standard was developed for simultaneously analyzing physostigmine and tetrahydroaminoacridine in skin samples, permeation diffusates and dosage form. Baseline resolution was achieved with an octadecyl column for physostigmine, its two degradation products and tetrahydroaminoacridine. Peak homogeneity of physostigmine and tetrahydroaminoacridine was confirmed. The calibration curves for both drugs in skin samples were established at 1-50 micrograms per 200 mg skin. Those for diffusate samples were at 10-50 ng per 50 microliters for physostigmine and 30-150 ng per 50 microliters for tetrahydroaminoacridine. The assay was reproducible with within-day and between-day variations of 5-6 and 4-10%, respectively. Application of the assay for in vitro transdermal permeation study was demonstrated.