Preferences for risks and benefits of treatment outcomes for chronic low back pain: Choice-based conjoint measure development and discrete choice experiment.

INTRODUCTION: Understanding individual patient preferences for chronic low back pain (cLBP) outcomes is essential for targeting available therapeutic options; yet tools to elicit patient outcome preferences are limited. OBJECTIVE: To develop and test a choice-based conjoint (CBC) measure, commonly used in behavioral economics research, to elicit what outcomes patients with cLBP want to achieve and avoid. DESIGN: We developed a survey-based CBC measure to allow patients to make risk/benefit trade-off choices between possible treatment outcomes. After extensive literature, clinician, and patient input, our measure included seven attributes: fatigue, anxiety/depression, difficulty thinking/making decisions, pain intensity, physical abilities, change in pain, and ability to enjoy life despite pain. Random-parameters logit models were used to estimate strength of preferences, and latent class analysis was used to identify patient characteristics associated with distinct preference. SETTING: Online study using the Sawtooth web-based platform. PARTICIPANTS: Two hundred eleven individuals with cLBP recruited from online advertising as well as at clinical sites across multiple academic and private institutions. INTERVENTIONS: Not applicable. RESULTS: The most valued outcome was the highest level of physical activity (ß = 1.6-1.98; p < .001), followed by avoiding cognitive difficulties (ß = -1.48; p < .001). Avoidance of severe pain was comparable to avoiding constant fatigue and near-constant depression/anxiety (ß = -0.99, -1.02); p < .001). There was an association between preferences and current pain/disability status; patients with higher pain had a stronger preference to avoid severe pain, whereas those with higher disability have stronger preferences for achieving physical activity. The latent class analysis identified two distinct groups: (1) more risk-seeking and willing to accept worse outcomes (56%); and (2) more risk-averse with a stronger preference for achieving maximum benefits (44%). CONCLUSIONS: Our study illuminated cLBP patient preferences for treatment outcomes and heterogeneity in these preferences. Patients stressed the importance of reaching high physical activity and avoiding cognitive declines, even over a desire to avoid pain. More work is needed to understand patient preferences to aid informed, shared decisions.

CAPER: patient preferences to inform nonsurgical treatment of chronic low back pain: a discrete-choice experiment.

OBJECTIVE: We developed and used a discrete-choice measure to study patient preferences with regard to the risks and benefits of nonsurgical treatments when they are making treatment selections for chronic low back pain. METHODS: "CAPER TREATMENT" (Leslie Wilson) was developed with standard choice-based conjoint procedures (discrete-choice methodology that mimics an individual's decision-making process). After expert input and pilot testing, our final measure had 7 attributes (chance of pain relief, duration of relief, physical activity changes, treatment method, treatment type, treatment time burden, and risks of treatment) with 3-4 levels each. Using Sawtooth software (Sawtooth Software, Inc., Provo, UT, USA), we created a random, full-profile, balanced-overlap experimental design. Respondents (n = 211) were recruited via an emailed online link and completed 14 choice-based conjoint choice pairs; 2 fixed questions; and demographic, clinical, and quality-of-life questions. Analysis was performed with random-parameters multinomial logit with 1000 Halton draws. RESULTS: Patients cared most about the chance of pain relief, followed closely by improving physical activity, even more than duration of pain relief. There was comparatively less concern about time commitment and risks. Gender and socioeconomic status influenced preferences, especially with relation to strength of expectations for outcomes. Patients experiencing a low level of pain (Pain, Enjoyment, and General Activity Scale [PEG], question 1, numeric rating scale score<4) had a stronger desire for maximally improved physical activity, whereas those in a high level of pain (PEG, question 1, numeric rating scale score>6) preferred both maximum and more limited activity. Highly disabled patients (Oswestry Disability Index score>40) demonstrated distinctly different preferences, placing more weight on achieving pain control and less on improving physical activity. CONCLUSIONS: Individuals with chronic low back pain were willing to trade risks and inconveniences for better pain control and physical activity. Additionally, different preference phenotypes exist, which suggests a need for clinicians to target treatments to particular patients.

Preferences for Risks and Benefits of Islet Cell Transplantation for Persons With Type 1 Diabetes With History of Episodes of Severe Hypoglycemia: A Discrete-Choice Experiment to Inform Regulatory Decisions.

BACKGROUND: The advisory panel for US Food and Drug Administration (FDA) recently endorsed pancreatic islet cell transplantation (ICT) therapy for suboptimally controlled type 1 diabetes (T1D), and FDA approval is under consideration. An important part of regulatory approval includes the patient perspective, through discrete choice. We developed a discrete-choice instrument and used it to determine how 90 people with T1D weigh the risks and benefits of ICT to inform regulatory decisions. METHODS: Sawtooth software created a random, full-profile, balanced-overlap experimental design for a measure with 8 attributes of ICT risks/benefits, each with 3 to 5 levels. We asked 18 random task pairs, sociodemographics, diabetes management, and hypoglycemia questions. Analysis was performed using random parameters logistic regression technique. RESULTS: The strongest preference was for avoiding the highest chance (15%) of serious procedure-related complications (ß = -2.03, P < 0.001). The strongest positive preference was for gaining 5-y insulin independence (ß = 1.75, P < 0.001). The desire for 5-y HbA1C-defined clinical treatment success was also strong (ß = 1.39, P < 0.001). Subgroup analysis suggested strong gender differences with women showing much higher preferences for all benefits (68% higher for 5-y insulin independence), and men were generally more risk averse than women. Those with high versus low diabetes distress showed 3 times stronger preference for 5-y insulin independence but also twice preference to avoid risks of serious complications. CONCLUSIONS: Despite showing the most preference for avoiding serious ICT complications, people with T1D had a strong preference for achieving ICT benefits, especially insulin independence. We identified important attributes of ICT and demonstrated that patients are willing to make these trade-offs, showing support for the introduction of ICT.

Analyzing excipient-related adverse events in antiseizure drug formulations.

There have been several reports that switching formulations of antiseizure medications (ASMs) has been associated with a deterioration of seizure control, seizure relapse or increased adverse effects. Considering recent findings that excipients, namely purported inactive ingredients, may nevertheless exert biological effects, it is possible that the variation in adverse event profile of antiseizure drugs may be related to differences in excipients. To test our hypothesis, we constructed a new research tool to connect FDA-compiled adverse event reports to the excipient in the medicine. Analysis of adverse events to formulations of five different second-generation antiseizure drugs - gabapentin, lamotrigine, levetiracetam, oxcarbazepine, and topiramate - showed several significant associations between specific excipient in the formulations and an adverse event when compared to the same medicine formulated with other excipients. Epilepsy and seizure adverse events were associated with multiple excipients across gabapentin, lamotrigine, and levetiracetam formulations. A different group of excipients were associated with reports of hypersensitivity reactions including urticaria, rash, erythema, and Stevens-Johnson syndrome. Our study provides a novel approach to analyzing post-market surveillance reports by including excipients. It may be useful to clinicians when evaluating select patient groups that may be refractory to pharmacological treatment or experience worsening adverse events when switching formulations of the same antiseizure medicine.

Cost-Effectiveness Analysis of Atezolizumab Versus Durvalumab as First-Line Treatment of Extensive-Stage Small-Cell Lung Cancer in the USA.

BACKGROUND AND OBJECTIVES: Durvalumab and atezolizumab are approved as first-line therapy in extensive-stage small-cell lung cancer. Although cost-effectiveness analyses compared these immunotherapy drugs with standard chemotherapy-alone regimens, no head-to-head cost-effectiveness comparisons for these treatments exist. The aim of the present analysis is to determine the cost-effectiveness of durvalumab and atezolizumab as first-line therapy for extensive-stage small-cell lung cancer from the US payers' perspective. METHODS: This study is based on two placebo-controlled, phase 3 clinical trials: CASPIAN and IMpower133. A Markov model was developed to simulate the three health states: progression-free survival, progressed disease, and death in patients with extensive-stage small-cell lung cancer. Transition probabilities were estimated from the clinical trial survival curves and extended with life-time modelling. Health utilities and direct costs of adverse event treatment were included. Main outcome was the incremental cost-effectiveness ratio (ICER) using quality-adjusted life-years saved (QALYS). Sensitivity analysis was performed to assess the impact of variables on the ICER. RESULTS: Durvalumab group has a cost of $187,503 with an effectiveness of 1.08 while atezolizumab has a cost of $160,219 and an effectiveness of 0.932. Durvalumab is not cost-effective compared to atezolizumab with an ICER of $165,182 QALYS, which is over the willingness-to-pay threshold of $150,000. The model was most sensitive to durvalumab cost and the cost of treating durvalumab adverse effects. CONCLUSIONS: With the ICER of durvalumab treatment group being very close to $150,000, setting a higher willingness-to-pay threshold or decreasing the drug cost through contract pricing can increase the cost-effectiveness of durvalumab compared to atezolizumab.

CYP2C19 Allele Frequencies in Over 2.2 Million Direct-to-Consumer Genetics Research Participants and the Potential Implication for Prescriptions in a Large Health System.

Understanding the prevalence of clinically relevant pharmacogenetic variants using large unselected populations is critical for gauging the potential clinical impact of widespread preemptive pharmacogenetic testing. To this end, we assessed the frequencies and ethnic distribution of the three most common CYP2C19 alleles (*2, *3, and *17) in 2.29 million direct-to-consumer genetics research participants (23andMe, Sunnyvale, CA). The overall frequencies of *2, *3, and *17 were 15.2%, 0.3%, and 20.4%, respectively, but varied by ethnicity. The most common variant diplotypes were *1/*17 at 26% and *1/*2 at 19.4%. The less common *2/*17, *17/*17, and *2/*2 genotypes occurred at 6.0%, 4.4%, and 2.5%, respectively. Overall, 58.3% of participants had at least one increased-function or no-function CYP2C19 allele. To better understand how this high frequency might impact a real patient population, we examined the prescription rates (Rx) of high-pharmacogenetic-risk medications metabolized by CYP2C19 using the University of California at San Francisco (UCSF) health system's anonymized database of over 1.25 million patients. Between 2012 and 2019, a total of 151,068 UCSF patients (15.8%) representing 5 self-reported ethnicities were prescribed one or more high-pharmacogenetic-risk CYP2C19 medications: proton pump inhibitors (145,243 Rx), three selective serotonin reuptake inhibitor antidepressants (54,463 Rx), clopidogrel (14,376 Rx), and voriconazole (2,303 Rx).

Biologic excipients: Importance of clinical awareness of inactive ingredients.

Due to the complexity and fragility of biological drug products, several challenges exist in their formulation development. Excipients are added to increase product stability, maintain tonicity, and facilitate drug delivery. The potential implications of these additive substances merit clinical consideration. We assessed the safety risk of excipients on the basis of their type and variability through an assessment framework, which quantifies excipient complexity in 230 biological formulations, and identifies excipient-related adverse events through published case reports. A biologic on average contained 4.45 excipients, half of that found in oral medications. The frequency distribution was heavily skewed towards the most commonly occurring excipients: water (40.4%), sodium chloride (38.3%), polysorbate 80 (28.7%), sucrose (24.4%), and mannitol (20.9%), with 44.4% of formulations not listing the concentration of the most commonly occurring inactive ingredients. A literature search revealed only 17 case reports of excipient-related adverse events, suggesting the need for more clarity for clinicians on the safety of chemical additives. These cases included injection site reactions, anaphylaxis, hyperglycemia, and acute renal failure. With the expansion of the biopharmaceutical market, it is important to consider the safety data of biologic excipients, so that therapy can be tailored appropriately for a specific patient.