Abstract Treatment with immune checkpoint inhibitors (ICPIs) extends survival in a proportion of patients across multiple cancers. Tumor mutational burden (TMB)—the number of somatic mutations per DNA megabase (Mb)—has emerged as a proxy for neoantigen burden that is an independent biomarker associated with ICPI outcomes. Based on findings from recent studies, TMB can be reliably estimated using validated algorithms from next-generation sequencing assays that interrogate a sufficiently large subset of the exome as an alternative to whole-exome sequencing. Biological processes contributing to elevated TMB can result from exposure to cigarette smoke and ultraviolet radiation, from deleterious mutations in mismatch repair leading to microsatellite instability, or from mutations in the DNA repair machinery. A variety of clinical studies have shown that patients with higher TMB experience longer survival and greater response rates following treatment with ICPIs compared with those who have lower TMB levels; this includes a prospective randomized clinical trial that found a TMB threshold of ≥10 mutations per Mb to be predictive of longer progression-free survival in patients with non-small cell lung cancer. Multiple trials are underway to validate the predictive values of TMB across cancer types and in patients treated with other immunotherapies. Here we review the rationale, algorithm development methodology, and existing clinical data supporting the use of TMB as a predictive biomarker for treatment with ICPIs. We discuss emerging roles for TMB and its potential future value for stratifying patients according to their likelihood of ICPI treatment response.
While literature has suggested that the duration of a major depressive episode (MDE) may affect both symptomatic and functional outcomes in major depressive disorder (MDD), study designs are limited in their ability to isolate a causal relationship.A targeted literature review was conducted using the MEDLINE database to assess whether there was an association between (1) shorter duration of an MDE, or (2) increased rapidity of symptom improvement, and MDD outcomes in adult patients. Given findings from the literature, we hypothesized that rapid symptom improvement could be associated with other longer-term clinical outcomes and used a previously-developed microsimulation model to test this hypothesis. The base case of the model replicated step-therapy treatment patterns, for 10,000 simulated patients, based on lines of therapy related to standard of care, observed remission rates, and observed time to relapse from the STAR*D study. In alternative scenario analyses, the step 1 remission rate was varied by +25 % and +50 % from the base case value to simulate the potential impact of improved earlier remission on disease trajectory and patient-level clinical outcomes.The literature review (N = 35 studies) suggests a statistically significant relationship between the duration of MDE or early symptom improvement and MDD outcomes. The microsimulation model corroborated these findings and demonstrated that increasing the rate of remission in step 1 results in patients experiencing decreased number of treatment steps, faster time to remission, decreased rate of reaching treatment-resistant depression, and delayed time to relapse.Rates of relapse in STAR*D were deemed unreliable due to the high-loss of follow-up; rates of relapse for the MDD DTM were instead derived using parametric extrapolation methods (i.e., exponential, Weibull, log-logistic, Gaussian, log-normal, logistic). Adherence to treatment was assumed to be 100 %; however, non-adherence is expected to result in lower cumulative remission rates.Findings from the literature, coupled with quantification through a novel microsimulation model, demonstrate the potential impact of increased remission on disease trajectory and patient outcomes in MDD. While additional analyses with the model may be warranted to explore the impact of novel interventions on population health, including long-term outcomes (i.e., 5-year follow-up, lifetime follow-up), efforts by clinicians to increase remission early in the disease trajectory may improve long-term outcomes.
Postpartum depression (PPD) is the most common medical complication of childbirth. PPD can be disabling, with potential negative effects on maternal health-related quality-of-life (HRQoL) as well as on children and partners. The objective of this study was to systematically review and summarize recently published literature describing the humanistic burden of PPD on affected women, their children, and partners.Databases including Embase, MEDLINE, and PsycINFO, as well as conference proceedings were searched for keywords related to PPD. Searches were initially conducted in February 2017 and restricted to the prior 5 years for databases and the prior 2 years for conference proceedings. Searches were updated in February 2018. Two researchers independently reviewed 1154 unique records according to pre-defined inclusion and exclusion screening criteria.Forty-eight studies were identified; over 40 studies assessed the effects of PPD on children of affected mothers, with many demonstrating a negative association with elements of parenting and childhood development. Furthermore, five studies that evaluated the effects of PPD symptoms on partners suggested that certain aspects of their relationships were negatively affected. Partners of affected women also experienced greater levels of their own stress, anxiety, and depression compared with partners of women without PPD symptoms. Despite limited data on HRQoL among women with PPD symptoms (four studies), a negative impact on physical and mental sub-scales was observed.Findings suggest that PPD symptoms have a substantial humanistic burden on affected mothers as well as on their children and partners.
Abuse of prescription opioids [opioid use disorder (OUD), poisoning, and fatal and non-fatal overdose] is a public health and economic challenge that is associated with considerable morbidity and mortality in the USA and globally. To systematically review and summarize the health economics literature published over the last 5 years that describes the economic burden of abuse of prescription opioids. Findings from searches of databases including MEDLINE, Embase, and Cochrane CENTRAL as well as hand searches of multiple conference abstracts were screened against predefined inclusion criteria to identify studies reporting cost and healthcare resource utilization (HRU) data associated with abuse of prescription opioids. A total of 49 unique studies were identified. Most of the studies examined direct costs and HRU, which were substantially higher for abusers of prescription opioids than non-abuser controls in several matched cohort analyses (US$20,343–US$28,718 vs US$9716–US$14,079 for mean direct combined annual healthcare costs reported in 6 studies). Although only a small number of studies reported indirect costs, these findings suggest a high societal burden related to productivity losses, absenteeism, morbidity, and mortality among those who abuse opioids. Studies of medication-assisted treatment demonstrated that factors such as adherence, dose, formulation (film or tablet), and relapse during treatment, were associated with direct costs and HRU among treated patients. This systematic literature review shows that abuse of prescription opioids is characterized by substantial direct healthcare costs, medical utilization, and related societal costs. Future research should further investigate the indirect costs of opioid abuse.
Prostate cancer is a highly prevalent form of cancer in older men and is one of the leading causes of death from cancer in men across the globe. Many therapeutic agents have been approved for patients with metastatic castration-resistant prostate cancer (mCRPC), particularly as a post-docetaxel treatment strategy. The objective of this systematic literature review was to assess published efficacy and safety data for select mCRPC therapies - such as abiraterone, cabazitaxel, and enzalutamide - in the post-docetaxel setting.Database searches of MEDLINE, Embase, and Cochrane CENTRAL, in conjunction with hand searches of multiple congress abstracts, yielded 13 randomized studies and 107 non-randomized studies that met the inclusion criteria.Randomized studies demonstrated significant improvements in median overall survival (OS) outcomes over placebo for abiraterone (15.8 vs. 11.2 months) and enzalutamide (18.4 vs. 13.6 months), and similar significant improvements were noted for cabazitaxel over mitoxantrone (15.1 vs. 12.7 months). Differences in progression-free survival (PFS) were similarly significant, although variance in the criteria for measuring PFS may limit the extent to which these outcomes can be compared between studies. Non-randomized evidence included multiple publications from several early access and compassionate use programs with a primary objective to report safety outcomes. Results from these studies largely reflected the findings in randomized trials.Overall, there is a growing body of evidence for post-docetaxel treatment options available in patients with mCRPC. Further head-to-head trials or indirect treatment comparisons may be a valuable method to assess the comparative efficacy of these therapies.
