Preferences and perceptions of patients with metastatic castration-resistant prostate cancer for treatments and biomarker testing: An international qualitative study

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Background: Metastatic castration-resistant prostate cancer (mCRPC) is a lethal disease with significant morbidity. Poly adenosine diphosphate-ribose polymerase inhibitors (PARPi) are targeted therapeutics approved to treat mCRPC patients with genetic mutations in homologous recombination repair (HRR). However, to benefit from PARPi as a single agent, patients usually need to undergo biomarker testing to determine their mutation status. As an initial step to understand patient preferences for mCRPC treatments, this study investigated the treatment features important to mCRPC patients and their preferences for and perceptions of biomarker testing. Methods: This preliminary qualitative study included 25 men in the US, UK, Germany, Spain, and Japan with self-reported mCRPC diagnosed at least 6 months previously. Participants completed a 60-minute one-on-one interview about mCRPC treatments and disease impact. Results: Participants had a mean age of 62 years and were diagnosed with prostate cancer an average of 68 months prior. About half (52%) had metastasized > 1 year prior and more than half (56%) reported no HRR genetic mutation . The most frequently reported symptoms were pain (60%), urinary problems (56%), and fatigue (32%). Participants stated that pain impacted their sleep, daily activities, and social lives. 60% reported they shared treatment decision-making with their physician, some (24%) shared it with partners or caregivers, and others (32%) left treatment decisions up to their physician due to their lack of knowledge. Quality of life (QoL) was the most important treatment benefit reported (56%), followed by progression-free survival (PFS) (52%), overall survival (OS) (48%), and reduced pain (44%). Some participants reported their desire for prolonged survival needed to be balanced with adequate QoL. Few participants reported reduced fatigue (24%) or urinary problems (12%) as desired treatment benefits. 64% had previously undergone biomarker testing to determine mutation status. 56% of tested participants reported that their physician discussed the purpose and benefits of testing. Based on conversations with their physicians, both tested and untested participants felt that biomarker testing would inform them about heritable risk of mutation and help find new targeted treatments. Untested participants with a negative view of biomarker testing (22%) reported concerns about the need for further invasive biopsies. Conclusions: QoL followed by PFS, OS, and reduced pain were the most important benefits of treatment to participants. More than half of participants had a positive view of biomarker testing, especially if testing could lead to targeted therapies and inform about heritable risk. These results will inform the design of an international discrete choice study of biomarker testing among men with mCRPC.

R and Shiny for Cost-Effectiveness Analyses: Why and When? A Hypothetical Case Study

INTRODUCTION

Health economics models are typically built in Microsoft Excel^® owing to its wide familiarity, accessibility and perceived transparency. However, given the increasingly rapid and analytically complex decision-making needs of both the pharmaceutical industry and the field of health economics and outcomes research (HEOR), the demands of cost-effectiveness analyses may be better met by the programming language R.

OBJECTIVE

This case study provides an explicit comparison between Excel and R for contemporary cost-effectiveness analysis.

METHODS

We constructed duplicate cost-effectiveness models using Excel and R (with a user interface built using the Shiny package) to address a hypothetical case study typical of contemporary health technology assessment.

RESULTS

We compared R and Excel versions of the same model design to determine the advantages and limitations of the modelling platforms in terms of (i) analytical capability, (ii) data safety, (iii) building considerations, (iv) usability for technical and non-technical users and (v) model adaptability.

CONCLUSIONS

The findings of this explicit comparison are used to produce recommendations for when R might be more suitable than Excel in contemporary cost-effectiveness analyses. We conclude that selection of appropriate modelling software needs to consider case-by-case modelling requirements, particularly (i) intended audience, (ii) complexity of analysis, (iii) nature and frequency of updates and (iv) anticipated model run time.

The Effect of the Modified Endoscopic Lothrop Procedure on the Mucociliary Clearance of the Frontal Sinus in an Animal Model

Background

The surgical management of recalcitrant frontal sinus disease has been a dilemma for otolaryngologists for many years. Although the osteoplastic flap with obliteration has been the gold standard of treatment for years, the modified endoscopic Lothrop (MEL) procedure recently has been advocated as an alternative. However, little is known about the effect of this procedure on the mucociliary drainage of the frontal sinuses postoperatively and this animal study addresses this issue.

Methods

Fourteen sheep underwent the MEL procedure. The sheep were randomized regarding the use of postoperative irrigation via minitrephines. Each sheep had a nuclear medicine γ-scintigraphy frontal sinus clearance study via minitrephines performed on each frontal sinus preoperatively and then 3 months postoperatively. Then, the results of these studies were compared.

Results

The scans revealed a trend toward faster clearance times postoperatively. However, this decrease was not statistically significant. Importantly, there was no trend or significant increase in clearance times postoperatively. Also, the use of postoperative irrigation was associated with a nonsignificant trend toward faster clearance times postoperatively.

Conclusion

The MEL procedure has no adverse effects on the mucociliary clearance of the frontal sinus at 3 months postoperatively. Irrigation of the frontal sinus in the immediate postoperative period showed a trend toward improved postoperative mucociliary function at 3 months.

Application of Physiologically Based Pharmacokinetic (PBPK) Modeling Within a Bayesian Framework to Identify Poor Metabolizers of Efavirenz (PM), Using a Test Dose of Efavirenz

Poor metabolisers of CYP2B6 (PM) require a lower dose of efavirenz because of serious adverse reactions resulting from the higher plasma concentrations associated with a standard dose. Treatment discontinuation is a common consequence in patients experiencing these adverse reactions. Such patients benefit from appropriate dose reduction, where efficacy can be achieved without the serious adverse reactions. PMs are usually identified by genotyping. However, in countries with limited resources genotyping is unaffordable. Alternative cost-effective methods of identifying a PM will be highly beneficial. This study was designed to determine whether a plasma concentration corresponding to a 600 mg test dose of efavirenz can be used to identify a PM. A physiologically based pharmacokinetic (PBPK) model was used to simulate the concentration-time profiles of a 600 mg dose of efavirenz in extensive metabolizers (EM), intermediate metabolizers (IM), and PM of CYP2B6. Simulated concentration-time data were used in a Bayesian framework to determine the probability of identifying a PM, based on plasma concentrations of efavirenz at a specific collection time. Results indicated that there was a high likelihood of differentiating a PM from other phenotypes by using a 24 h plasma concentration. The probability of correctly identifying a PM phenotype was 0.82 (true positive), while the probability of not identifying any other phenotype as a PM (false positive) was 0.87. A plasma concentration >1,000 ng/mL at 24 h post-dose is likely to be from a PM. Further verification of these findings using clinical studies is recommended.

Applications of linking PBPK and PD models to predict the impact of genotypic variability, formulation differences, differences in target binding capacity and target site drug concentrations on drug responses and variability

This study aimed to demonstrate the added value of integrating prior in vitro data and knowledge-rich physiologically based pharmacokinetic (PBPK) models with pharmacodynamics (PDs) models. Four distinct applications that were developed and tested are presented here. PBPK models were developed for metoprolol using different CYP2D6 genotypes based on in vitro data. Application of the models for prediction of phenotypic differences in the pharmacokinetics (PKs) and PD compared favorably with clinical data, demonstrating that these differences can be predicted prior to the availability of such data from clinical trials. In the second case, PK and PD data for an immediate release formulation of nifedipine together with in vitro dissolution data for a controlled release (CR) formulation were used to predict the PK and PD of the CR. This approach can be useful to pharmaceutical scientists during formulation development. The operational model of agonism was used in the third application to describe the hypnotic effects of triazolam, and this was successfully extrapolated to zolpidem by changing only the drug related parameters from in vitro experiments. This PBPK modeling approach can be useful to developmental scientists who which to compare several drug candidates in the same therapeutic class. Finally, differences in QTc prolongation due to quinidine in Caucasian and Korean females were successfully predicted by the model using free heart concentrations as an input to the PD models. This PBPK linked PD model was used to demonstrate a higher sensitivity to free heart concentrations of quinidine in Caucasian females, thereby providing a mechanistic understanding of a clinical observation. In general, permutations of certain conditions which potentially change PK and hence PD may not be amenable to the conduct of clinical studies but linking PBPK with PD provides an alternative method of investigating the potential impact of PK changes on PD.

The effect of the modified endoscopic Lothrop procedure on the mucociliary clearance of the frontal sinus in an animal model

BACKGROUND

The surgical management of recalcitrant frontal sinus disease has been a dilemma for otolaryngologists for many years. Although the osteoplastic flap with obliteration has been the gold standard of treatment for years, the modified endoscopic Lothrop (MEL) procedure recently has been advocated as an alternative. However, little is known about the effect of this procedure on the mucociliary drainage of the frontal sinuses postoperatively and this animal study addresses this issue.

METHODS

Fourteen sheep underwent the MEL procedure. The sheep were randomized regarding the use of postoperative irrigation via minitrephines. Each sheep had a nuclear medicine gamma-scintigraphy frontal sinus clearance study via minitrephines performed on each frontal sinus preoperatively and then 3 months postoperatively. Then, the results of these studies were compared.

RESULTS

The scans revealed a trend toward faster clearance times postoperatively. However, this decrease was not statistically significant. Importantly, there was no trend or significant increase in clearance times postoperatively. Also, the use of postoperative irrigation was associated with a nonsignificant trend toward faster clearance times postoperatively.

CONCLUSION

The MEL procedure has no adverse effects on the mucociliary clearance of the frontal sinus at 3 months postoperatively. Irrigation of the frontal sinus in the immediate postoperative period showed a trend toward improved postoperative mucociliary function at 3 months.

Nurses' perceptions of people who are homeless

There are few data-based reports about the perceptions of nurses toward marginalized groups and even fewer about the transformation of perceptions. The purpose of this study was to explore nurses' perceptions of people who are homeless and to describe transforming experiences. Rich, detailed experiences of the care provided to people who were homeless were elicited through in-depth interviews with 15 nurses and nursing students. Without exception, each participant in this study indicated that listening, connecting, and understanding were important to them in changing previously held negative beliefs. However, when clients did not express appreciation or behave in expected ways, nurses became frustrated and voiced negative feelings about people who are homeless. Study findings emphasize the importance of listening and connecting with people who are different from ourselves so that our shared humanity is acknowledged and appreciated.

Exogenous myeloperoxidase enhances bacterial phagocytosis and intracellular killing by macrophages

It is well documented that myeloperoxidase (MyPo) contributes to the bacterial activities of neutrophils and monocytes. Since mature macrophages (M phi) are devoid of this enzyme, its participation in M phi-mediated phagocytes and bacterial killing has not been completely defined. The present study demonstrates the exogenously added MyPo, at physiological levels, enhances both phagocytosis and killing of Escherichia coli. Murine peritoneal M phi were exposed to various concentrations of MyPo for different time intervals. Viable opsonized E. coli was added either prior to or after addition of MyPo. Thioglycolate-induced but not resident M pho exhibited an increase in the number of phagocytizing cells. Both resident and thioglycolate-induced M phi demonstrated increased bactericidal activity. Physiological levels of soluble MyPo also induced a significant increase in chemiluminescence. Since luminol-dependent chemiluminescence measures reactive oxygen intermediate production, studies were done to determine whether superoxide anion or H2O2 was involved in MyPo-induced M pho killing. Both superoxide dismutase and catalase ablated MyPo-induced bactericidal activity. The above data suggest that soluble MyPo, released from neutrophils at a site of infection or inflammation, can enhance both phagocytosis and killing of microorganisms.

Knee motion following multiple soft-tissue releases in ambulatory patients with cerebral palsy

Multiple soft-tissue releases (MSTRs) in cerebral palsy have been advocated to improve knee motion during gait. Forty-five extremities underwent MSTRs as recommended by preoperative gait analysis. Pre- and postoperative analyses were evaluated in relation to knee motion and foot progression angle. Maximum knee flexion during swing and the foot progression angle showed no significant change postoperatively. The total knee ROM and minimum knee flexion in stance improved significantly towards normal. The timing of maximum knee flexion and slope of the knee flexion curve at toe off improved with respect to age and number of previous surgeries. MSTRs increased knee ROM and improved the sequential timing and event progression during gait.

Faecal incontinence: manometric and radiological changes following postanal repair

Ten patients with idiopathic faecal incontinence underwent postanal repair based on clinical assessment of their symptoms. Their manometric and radiological values before surgery were compared with values from 10 normal volunteers and then the changes following surgery were examined and correlated with the clinical results. Anal manometry was performed using a multilumen, low compliance, perfused catheter system. Anorectal angles and perineal descent were established radiologically. Pre-operative manometry demonstrated significant reduction in maximum and squeeze pressure (median 77 mmHg versus 200 mmHg), the volume required to inhibit the rectoanal reflex (median 40 mL versus 70 mL), and the volume retained in the saline continence test (median 400 mL versus 1500 mL). The majority of patients had obtuse anorectal angles (six of 10 at rest), and abnormal perineal descent (eight of 10 on straining). Nine patients have been improved clinically following surgery. Postoperative manometry and radiology have been performed in seven patients and have shown no significant changes. Anal manometry and radiology are objective means of documenting faecal incontinence although their role in selecting patients for surgery is not yet determined. Postanal repair is effective in restoring continence, although the parameters measured have not explained the mechanism of this effect.

Shortening of the first metatarsal as a complication of metatarsal osteotomies

There have been few reports of shortening of the first ray of the foot because of damage to the physis of the first metatarsal during the performance of metatarsal osteotomy for residual metatarsus adductus. In a retrospective study of twenty-seven feet in twenty patients who underwent this procedure, eight feet in seven patients were noted to have some degree of residual shortening of the first ray. This is an incidence of 30 per cent. The follow-up period after osteotomy ranged from two years to seven years and four months (average, four years). We could find no clear correlation between the occurrence of shortening and the patient's age at osteotomy, sex, or race, or the etiology of the adduction for which the osteotomy had been done. A clear correlation was found, however, with the surgical technique that had been employed. In two of the eight feet with a short first ray, the osteotomy had been done within the physis of the first metatarsal. In the other feet the procedure had employed an osteotomy site close to the physis or extensive periosteal dissection, or both. The results in our patients implicate subperiosteal dissection of the first metatarsal as an important, previously unreported cause of damage to the physis and of the resultant shortening. We recommend radiographic determination of the relationship of the osteotomy site to the physis before dissection is performed.

Operation for discrete subvalvular aortic stenosis

Over the past 20 years, 37 patients (31 children and six adults) have undergone operations for discrete subvalvular aortic stenosis. Prior to 1975, resection of the subvalvular membrane alone was the procedure of choice. However, the recurrence rate was high (36%). Since 1975, resection of the membrane plus left ventricular myectomy has been routine. The recurrence rate in this group has been lower (20%) but is still high. Overall, 11 patients (30%) have had significant recurrence (average gradient 63 mm Hg). Eight of these 11 have undergone a second operation with re-resection of a membrane and left ventricular myectomy. One patient died and in three others (42%) significant symptoms and gradients remained. One of these three has undergone a successful aortoventriculoplasty, and two patients are awaiting a similar operation. Lessons learned from this experience include the following: (1) Regardless of the type of initial operation, a significant rate of recurrence can be anticipated. (2) Progressive aortic insufficiency and fibromuscular tunnel stenosis occur commonly unless adequate relief of the obstruction is achieved by the first operation. (3) Because repeat resection with left ventricular myectomy is unlikely to be effective when aortic insufficiency and/or tunnel stenosis are present, aortoventriculoplasty should be employed as the definitive reoperative procedure.