Multimethod quantitative benefit-risk assessment of treatments for moderate-to-severe osteoarthritis.

OBJECTIVE: Demonstrate how benefit-risk profiles of systemic treatments for moderate-to-severe osteoarthritis (OA) can be compared using a quantitative approach accounting for patient preference. STUDY DESIGN AND SETTING: This study used a multimethod benefit-risk modelling approach to quantifiably compare treatments of moderate-to-severe OA. In total four treatments and placebo were compared. Comparisons were based on four attributes identified as most important to patients. Patient Global Assessment of Osteoarthritis was included as a favourable effect. Unfavourable effects, or risks, included opioid dependence, nonfatal myocardial infarction and rapidly progressive OA leading to total joint replacement. Clinical data from randomized clinical trials, a meta-analysis of opioid dependence and a long-term study of celecoxib were mapped into value functions and weighted with patient preferences from a discrete choice experiment. RESULTS: Lower-dose NGFi had the highest weighted net benefit-risk score (0.901), followed by higher-dose NGFi (0.889) and NSAIDs (0.852), and the lowest score was for opioids (0.762). Lower-dose NGFi was the highest-ranked treatment option even when assuming a low incidence (0.34% instead of 4.7%) of opioid dependence (ie, opioid benefit-risk score 808) and accounting for both the uncertainty in clinical effect estimates (first rank probability 46% vs 20% for NSAIDs) and imprecision in patient preference estimates (predicted choice probability 0.26, 95% confidence interval [CI] 0.25-0.28 vs 0.21, 95% CI 0.19-0.23 for NSAIDs). CONCLUSION: The multimethod approach to quantitative benefit-risk modelling allowed the interpretation of clinical data from the patient perspective while accounting for uncertainties in the clinical effect estimates and imprecision in patient preferences.

The Patient Voice: Exploring Treatment Preferences in Participants with Mild Cognitive Concerns to Inform Regulatory Decision Making.

OBJECTIVE: We aimed to assess the feasibility of developing a discrete-choice experiment survey to elicit preferences for a treatment to delay cognitive decline among people with a clinical syndrome consistent with early Alzheimer's disease, including the development of self-reported screening criteria to recruit the sample. METHODS: Using input from qualitative interviews, we developed a discrete-choice experiment survey containing a multifaceted beneficial treatment attribute related to slowing cognitive decline for respondents with self-reported cognitive concerns. In two rounds of in-person pretest interviews, we tested and revised the survey text and discrete-choice experiment questions, including examples, language, and levels associated with the Alzheimer's Disease Assessment Scale-Cognitive Subscale, along with a set of de novo self-reported questions for identifying respondents who had neither too mild nor too advanced cognitive decline. Self-reported memory and thinking problems were compared with symptoms from studies of patients with early Alzheimer's disease (e.g., mild cognitive impairment, mild Alzheimer's disease) to determine whether those studies' recruited patients were similar to our anticipated target population. Round 1 pretest interviews resulted in significant simplifications in the survey instrument, revisions to the inclusion and exclusion criteria, and revisions to the screening process. In round 2 of the pretest interviews, the ability of participants to provide consistent responses to the self-reported screening questions was further assessed. In addition, to evaluate participants' ability to understand and independently complete the discrete-choice experiment survey, two interviewers independently evaluated each participant's ability to make trade-offs in the discrete-choice experiment questions and to understand the content of the survey. RESULTS: Round 1 (15 pretest interviews) identified challenges with the survey instrument related to the complexity of the choice questions. The screening process did not screen out seven respondents with more advanced cognitive decline, as determined qualitatively by the interviewers and by these participants' inability to complete the survey. The survey instrument and screening criteria were revised, and an initial online screener was added to the screening process before round 2 pretests. In round 2 pretests, 12 participants reported cognitive problems similar to the target population for the survey but were judged able to understand and independently complete the discrete-choice experiment survey. CONCLUSIONS: We developed self-reported screening criteria that identified a sample of individuals with memory and thinking concerns who were similar to individuals with clinical symptoms of early Alzheimer's disease and who were able to independently complete a simplified discrete-choice experiment survey. Quantitative patient preference studies provide important information on patients' willingness to trade off treatment benefits/risks. Adapting the technique for patients with cognitive decline requires careful testing and adjustments to survey instruments. This work suggests it is the severity of cognitive impairment, rather than its presence, that determines the ability to complete a simplified discrete-choice experiment survey.

Patient Preferences in Rare Diseases: A Qualitative Study in Neuromuscular Disorders to Inform a Quantitative Preference Study.

INTRODUCTION: It has become increasingly important to include patient preference information in decision-making processes for drug development. As neuromuscular disorders represent multisystem, debilitating, and progressive rare diseases with few treatment options, this study aimed to explore unmet health care needs and patient treatment preferences for two neuromuscular disorders, myotonic dystrophy type 1 (DM1) and mitochondrial myopathies (MM) to inform early stages of drug development. METHODS: Fifteen semi-structured interviews and five focus group discussions (FGDs) were held with DM1 and MM adult patients and caregivers. Topics discussed included (1) reasons for study participation; (2) disease signs/symptoms and their impact on daily lives; (3) top desired benefits; and (4) acceptability of risks and tolerance levels for a hypothetical new treatment. Data were analyzed following a thematic 'code' approach. RESULTS: A total of 52 participants representing a wide range of disease severities participated. 'Muscle strength' and 'energy and endurance' were the disease-related unmet needs most often mentioned. Additionally, improved 'balance', 'cognition' and 'gut function' were the top desired treatment benefits, while 'damage to the liver, kidneys or eyes' was the most concerning risk. Factors influencing their tolerance to risks related to previously having experienced the risk and differentiation between permanent and temporary risks. A few differences were elicited between patients and caregivers. CONCLUSIONS: This qualitative study provided an open forum to elicit treatment-desired benefits and acceptable risks to be established by patients themselves. These findings can inform decisions for developing new treatments and the design of clinical trials for DM1 and MM.

Selective cell uptake of modified Tat peptide-fluorophore conjugates in rat retina in ex vivo and in vivo models.

PURPOSE: To determine the pattern of retinal uptake of modified Tat peptide-fluorophore conjugates in the rat after ex vivo application and intravitreal injection. METHODS: Modified Tat peptide (RKKRRORRRGC) was conjugated at the C terminus to Alexa Fluor 594 to enable visualization of uptake. In the ex vivo model, posterior segments were incubated for up to 120 minutes in peptide solution. In the in vivo model, intravitreal injections of 5 microL peptide solution were performed in anesthetized rats, which were then euthanatized from 1 hour to 7 days after injection. Retinal and optic nerve paraffin sections were examined for fluorescent labeling. Immunohistochemistry for retinal cell markers was performed to identify cell types exhibiting uptake. RESULTS: The pattern of labeling seen in retinal sections was highly similar for the ex vivo and in vivo experiments, with specific uptake by retinal ganglion cells (RGCs) and by a subset of inner nuclear layer cells. The pattern of labeling remained specific even at the later time points. In the in vivo model, fluorescence was also noted in the nerve fiber layer and anterior optic nerve, extending posteriorly along the optic nerve at later time points. CONCLUSIONS: A specific pattern of uptake for modified Tat peptides was consistently seen in the rodent retina. Given the preferential uptake of these peptides by RGCs and the potential to conjugate diverse moieties, modified Tat peptides may be useful for delivery of therapeutic agents or molecular imaging probes to RGCs.

Implementation of Structured Benefit-Risk Assessments in Marketing Authorization Applications: Lessons Learned.

BACKGROUND: A recent publication from Eli Lilly and Company provided guidance on incorporation of a structured benefit-risk assessment framework into Section 2.5.6 of the Clinical Overview of marketing authorization applications. Because a template alone cannot deliver a judicious benefit-risk evaluation, the purpose of this manuscript is to present lessons learned and practical approaches that pharmaceutical companies (sponsors) can apply in developing holistic benefit risk assessments of medicinal products for their marketing authorization applications. METHODS: Benefit-risk scientists at Eli Lilly and Company facilitated use of a structured benefit-risk assessment in Section 2.5.6 of the Clinical Overview for a number of marketing authorization applications submitted to regulators between 2013 and the 2016. Based on our experiences in implementing the approach described in the publication by Wolka et al, we have identified commonalities that contributed to successful implementation. RESULTS: The 3 key learnings from the authors' experience are to (1) use a cross-functional team approach; (2) employ a process that lends to the objectivity and efficiency of benefit-risk assessments; and (3) leverage data visualizations for clear and concise communication of benefit-risk information. CONCLUSIONS: Sponsors can apply these approaches to incorporate benefit-risk assessments into their marketing authorization applications. Further shared learnings and benchmarking among the pharmaceutical industry will be necessary to further advance the science and practice of benefit-risk assessment.

Incorporation of a Benefit-Risk Assessment Framework Into the Clinical Overview of Marketing Authorization Applications.

BACKGROUND: The main responsibility of regulators and industry is to ensure the benefit-risk balance of pharmaceutical products is positive for the intended patient populations. In recent decades, regulators and industry have taken steps to systematize benefit-risk decision making related to marketing authorization applications through the use of structured benefit-risk assessment. METHODS: This manuscript presents an outline for a structured benefit-risk assessment that can be incorporated into Section 2.5.6 of the Clinical Overview to provide the basis for approval of pharmaceutical products in these regulatory submissions. RESULTS: The structured format presents the benefits and risks of a pharmaceutical product in the context of the medical need in the disease state, the benefits and risks of available pharmacologic and nonpharmacologic therapies, and the approach for mitigating the risks of the product under review. CONCLUSIONS: Ultimately, such an approach that lends further support to quality decision making would be beneficial to patients who would be treated with new pharmaceutical products.

Synthesis and characterization of a small, membrane-permeant, caspase-activatable far-red fluorescent peptide for imaging apoptosis.

To image apoptosis in vivo with a small, membrane-permeant probe, TcapQ(647) was synthesized comprising a Tat-peptide-based permeation peptide sequence, an effector caspase recognition sequence, DEVD, and a flanking optically activatable pair comprising a far-red quencher, QSY 21, and a fluorophore, Alexa Fluor 647. Under baseline conditions, high quenching efficiencies were observed resulting in low background fluorescence. Upon exposure to executioner caspases, TcapQ(647) was specifically cleaved, thereby releasing the fluorophore from the quencher and enabling imaging of apoptosis.

An open-label safety and pharmacokinetics study of duloxetine in pediatric patients with major depression.

OBJECTIVE: This preliminary, 32-week study assessed the safety, tolerability, and pharmacokinetics of duloxetine in pediatric patients (aged 7-17 years) with major depressive disorder. METHODS: Patients received flexible duloxetine doses of 20-120 mg once daily, with dose changes made based on clinical improvement and tolerability. Pharmacokinetic samples were collected across all duloxetine doses, and data were analyzed using population modeling. Primary outcome measures included treatment-emergent adverse events (TEAEs), vital signs, and Columbia-Suicide Severity Rating Scale (C-SSRS). RESULTS: Of the 72 enrolled patients, 48 (66.7%) completed acute treatment (18 weeks) and 42 (58.3%) completed extended treatment. Most patients (55/72; 76%) required doses ≥ 60 mg once daily to optimize efficacy based on investigator judgment and Clinical Global Impressions-Severity score. Body weight and age did not significantly affect duloxetine pharmacokinetic parameters. Typical duloxetine clearance in pediatric patients was ≈ 42%-60% higher than that in adults. Four patients (5.6%) discontinued due to TEAEs. Many (36/72, 50%) patients experienced potentially clinically significant (PCS) elevations in blood pressure, with most cases (21/36, 58%) being transient. As assessed via C-SSRS, one nonfatal suicidal attempt occurred, two patients (2.8%) experienced worsening of suicidal ideation, and among the 19 patients reporting suicidal ideation at baseline, 17 (90%) reported improvement in suicidal ideation. CONCLUSION: Results suggested that pediatric patients generally tolerated duloxetine doses of 30 to 120 mg once daily, although transient PCS elevations in blood pressure were observed in many patients. Pharmacokinetic results suggested that adjustment of total daily dose based on body weight or age is not warranted for pediatric patients and different total daily doses may not be warranted for pediatric patients relative to adults.

Biochemical and in vivo characterization of a small, membrane-permeant, caspase-activatable far-red fluorescent peptide for imaging apoptosis.

Apoptosis is an important process involved in diverse developmental pathways, homeostasis, and response to therapy for a variety of diseases. Thus, noninvasive methods to study regulation and to monitor cell death in cells and whole animals are desired. To specifically detect apoptosis in vivo, a novel cell-permeable activatable caspase substrate, TcapQ647, was synthesized and Km, kcat, and Ki values were biochemically characterized. Specific cleavage of TcapQ647 by effector caspases was demonstrated using a panel of purified recombinant enzyme assays. Of note, caspase 3 was shown to cleave TcapQ647 with a kcat 7-fold greater than caspase 7 and 16-fold greater than caspase 6. No evidence of TcapQ647 cleavage by initiator caspases was observed. In KB 3-1 or Jurkat cells treated with cytotoxic agents or C6-ceramide, TcapQ647 detected apoptosis in individual- and population-based fluorescent cell assays in an effector caspase inhibitor-specific manner. Further, only background fluorescence was observed in cells incubated with dTcapQ647, a noncleavable all d-amino acid control peptide. Finally, in vivo experiments demonstrated the utility of TcapQ647 to detect parasite-induced apoptosis in human colon xenograft and liver abscess mouse models. Thus, TcapQ647 represents a sensitive, effector caspase-specific far-red "smart" probe to noninvasively monitor apoptosis in vivo.

Permeation peptide conjugates for in vivo molecular imaging applications.

Rapid and efficient delivery of imaging probes to the cell interior using permeation peptides has enabled novel applications in molecular imaging. Membrane permeant peptides based on the HIV-1 Tat basic domain sequence, GRKKRRQRRR, labeled with fluorophores and fluorescent proteins for optical imaging or with appropriate peptide-based motifs or macrocycles to chelate metals, such as technetium for nuclear scintigraphy and gadolinium for magnetic resonance imaging, have been synthesized. In addition, iron oxide complexes have been functionalized with the Tat basic domain peptides for magnetic resonance imaging applications. Herein we review current applications of permeation peptides in molecular imaging and factors influencing permeation peptide internalization. These diagnostic agents show concentrative cell accumulation and rapid kinetics and display cytosolic and focal nuclear accumulation in human cells. Combining methods, dual-labeled permeation peptides incorporating fluorescein maleimide and chelated technetium have allowed for both qualitative and quantitative analysis of cellular uptake. Imaging studies in mice following intravenous administration of prototypic diagnostic permeation peptides show rapid whole-body distribution allowing for various molecular imaging applications. Strategies to develop permeation peptides into molecular imaging probes have included incorporation of targeting motifs such as molecular beacons or protease cleavable domains that enable selective retention, activatable fluorescence, or targeted transduction. These novel permeation peptide conjugates maintain rapid translocation across cell membranes into intracellular compartments and have the potential for targeted in vivo applications in molecular imaging and combination therapy.

TAT-BH4 and TAT-Bcl-xL peptides protect against sepsis-induced lymphocyte apoptosis in vivo.

Apoptosis is a key pathogenic mechanism in sepsis that induces extensive death of lymphocytes and dendritic cells, thereby contributing to the immunosuppression that characterizes the septic disorder. Numerous animal studies indicate that prevention of apoptosis in sepsis improves survival and may represent a potential therapy for this highly lethal disorder. Recently, novel cell-penetrating peptide constructs such as HIV-1 TAT basic domain and related peptides have been developed to deliver bioactive cargoes and peptides into cells. In the present study, we investigated the effects of sepsis-induced apoptosis in Bcl-x(L) transgenic mice and in wild-type mice treated with an antiapoptotic TAT-Bcl-x(L) fusion protein and TAT-BH4 peptide. Lymphocytes from Bcl-x(L) transgenic mice were resistant to sepsis-induced apoptosis, and these mice had a approximately 3-fold improvement in survival. TAT-Bcl-x(L) and TAT-BH4 prevented Escherichia coli-induced human lymphocyte apoptosis ex vivo and markedly decreased lymphocyte apoptosis in an in vivo mouse model of sepsis. In conclusion, TAT-conjugated antiapoptotic Bcl-2-like peptides may offer a novel therapy to prevent apoptosis in sepsis and improve survival.

Characterization of novel histidine-tagged Tat-peptide complexes dual-labeled with (99m)Tc-tricarbonyl and fluorescein for scintigraphy and fluorescence microscopy.

To enable concurrent whole body scintigraphy and direct imaging of subcellular localization of permeation peptides, dual-labeled Tat-peptides useful for both radiometric analysis and fluorescence microscopy are desired for molecular imaging applications. Thus, novel dual-labeled D-Tat-peptides comprising Tat-basic domain (hgrkkrrqrrrgc), C-terminus conjugated with fluorescein-5-maleimide (FM) and N-terminus chelated with [(99m)Tc(CO)(3)] via histidine coordination, were synthesized and characterized. In human Jurkat cells, radiotracer uptake and washout studies revealed concentration-dependent accumulation of the dual-labeled Tat-peptide within cells. Subcellular localization of Tat-peptide was confirmed by fluorescence microscopy using an analogous [Re(CO)(3)] dual-labeled Tat-peptide. As seen with C-terminus single-labeled Tat-peptides, localization to the nucleoli was observed with the dual-labeled Tat-peptide, suggesting that the mechanism of Tat-peptide uptake and localization was not dependent on free peptide termini at either end. In Balb/c mice, biodistribution studies performed with the dual-labeled Tat-peptide showed fluorescence intensity by microscopic analysis that visually confirmed and correlated directly with scintigraphic and radiometric data. Of note, following intravenous administration, little brain penetration of these permeation sequences was observed in vivo. His[(99m)Tc(CO)(3)]-, DTPA[(99m)Tc(CO)(3)]-, and epsilon-lys-gly-cys[(99m)Tc(O)]-labeled Tat-peptides showed significant pharmacokinetic differences in liver and kidney depending on labeling strategy, indicating that Tat-peptide biodistribution can be impacted by the chelation moiety coordinated with (99m)Tc. Thus, we have shown that dual-labeled (99m)Tc-tricarbonyl Tat-peptide-FM conjugates can be conveniently synthesized and enable direct comparison of quantitative radiometric and qualitative fluorescence data both in vitro as well as in vivo.