Beyond p-values: A phase II dual-criterion design with statistical significance and clinical relevance.

Background Well-designed phase II trials must have acceptable error rates relative to a pre-specified success criterion, usually a statistically significant p-value. Such standard designs may not always suffice from a clinical perspective because clinical relevance may call for more. For example, proof-of-concept in phase II often requires not only statistical significance but also a sufficiently large effect estimate. Purpose We propose dual-criterion designs to complement statistical significance with clinical relevance, discuss their methodology, and illustrate their implementation in phase II. Methods Clinical relevance requires the effect estimate to pass a clinically motivated threshold (the decision value (DV)). In contrast to standard designs, the required effect estimate is an explicit design input, whereas study power is implicit. The sample size for a dual-criterion design needs careful considerations of the study's operating characteristics (type I error, power). Results Dual-criterion designs are discussed for a randomized controlled and a single-arm phase II trial, including decision criteria, sample size calculations, decisions under various data scenarios, and operating characteristics. The designs facilitate GO/NO-GO decisions due to their complementary statistical-clinical criterion. Limitations While conceptually simple, implementing a dual-criterion design needs care. The clinical DV must be elicited carefully in collaboration with clinicians, and understanding similarities and differences to a standard design is crucial. Conclusion To improve evidence-based decision-making, a formal yet transparent quantitative framework is important. Dual-criterion designs offer an appealing statistical-clinical compromise, which may be preferable to standard designs if evidence against the null hypothesis alone does not suffice for an efficacy claim.

Modelling Spillover Effects on Informal Carers: The Carer QALY Trap.

The provision of informal (unpaid) care can impose significant 'spillover effects' on carers, and accounting for these effects is consistent with the efficiency and equity objectives of health technology assessment (HTA). Inclusion of these effects in health economic models, particularly carer health-related quality of life (QOL), can have a substantial impact on net quality-adjusted life year (QALY) gains and the relative cost effectiveness of new technologies. Typically, consideration of spillover effects improves the value of a technology, but in some circumstances, consideration of spillover effects can lead to situations whereby life-extending treatments for patients may be considered cost ineffective due to their impact on carer QOL. In this piece we revisit the classic 'QALY trap' and introduce an analogous 'carer QALY trap' which may have practical implications for economic evaluations where the inclusion of carer QOL reduces incremental QALY gains. Such results may align with a strict QALY-maximisation rule, however we consider the extent to which this principle may be at odds with the preferences of carers themselves (and possibly society more broadly), potentially leading decision makers into the carer QALY trap as a result. We subsequently reflect on potential solutions, highlighting the important (albeit limited) role that deliberation has to play in HTA.

Addressing challenges with real-world synthetic control arms to demonstrate the comparative effectiveness of Pralsetinib in non-small cell lung cancer.

As advanced non-small cell lung cancer (aNSCLC) is being increasingly divided into rare oncogene-driven subsets, conducting randomised trials becomes challenging. Using real-world data (RWD) to construct control arms for single-arm trials provides an option for comparative data. However, non-randomised treatment comparisons have the potential to be biased and cause concern for decision-makers. Using the example of pralsetinib from a RET fusion-positive aNSCLC single-arm trial (NCT03037385), we demonstrate a relative survival benefit when compared to pembrolizumab monotherapy and pembrolizumab with chemotherapy RWD cohorts. Quantitative bias analyses show that results for the RWD-trial comparisons are robust to data missingness, potential poorer outcomes in RWD and residual confounding. Overall, the study provides evidence in favour of pralsetinib as a first-line treatment for RET fusion-positive aNSCLC. The quantification of potential bias performed in this study can be used as a template for future studies of this nature.

Association Between Smoking History and Overall Survival in Patients Receiving Pembrolizumab for First-Line Treatment of Advanced Non-Small Cell Lung Cancer.

Importance: There is a need to tailor treatments to patients who are most likely to derive the greatest benefit from them to improve patient outcomes and enhance cost-effectiveness of cancer therapies. Objective: To compare overall survival (OS) between patients with a current or former history of smoking with patients who never smoked and initiated pembrolizumab monotherapy as first-line (1L) treatment for advanced non-small lung cancer (NSCLC). Design, Setting, and Participants: This retrospective cohort study compared patients diagnosed with advanced NSCLC aged 18 or higher selected from a nationwide real-world database originating from more than 280 US cancer clinics. The study inclusion period was from January 1, 2011, to October 1, 2019. Exposures: Smoking status at the time of NSCLC diagnosis. Main Outcomes and Measures: OS measured from initiation of 1L pembrolizumab monotherapy. Results: In this retrospective cohort study, a total of 1166 patients (median [IQR] age, 72.9 [15.3] years; 581 [49.8%] men and 585 [50.2%] women) were assessed in the primary analysis, including 91 patients [7.8%] with no history of smoking (ie, never-smokers) and 1075 patients [92.2%] who currently or formerly smoked (ie, ever-smokers). Compared with ever-smokers, never-smokers were older (median age [IQR] of 78.2 [12.0] vs 72.7 [15.5] years), more likely to be female (61 [67.0%] vs 524 [48.7%]) and to have been diagnosed with nonsquamous tumor histology (70 [76.9%] vs 738 [68.7%]). After adjustment for baseline covariates, ever-smokers who initiated 1L pembrolizumab had significantly prolonged OS compared to never-smokers (median OS: 12.8 [10.9-14.6] vs 6.5 [3.3-13.8] months; hazard ratio (HR): 0.69 [95% CI, 0.50-0.95]). This trend was observed across all sensitivity analyses for the 1L pembrolizumab cohort, but not for initiators of 1L platinum chemotherapy, for which ever-smokers showed significantly shorter OS compared with never-smokers (HR, 1.2 [95% CI, 1.07-1.33]). Conclusions and Relevance: In patients with advanced NSCLC who received 1L pembrolizumab monotherapy in routine clinical practices in the US, patients who reported a current or former history of smoking at the time of diagnosis had consistently longer OS than never-smokers. This finding suggests that in never-smoking advanced NSCLC, 1L pembrolizumab monotherapy may not be the optimal therapy selection, and genomic testing for potential genomically matched therapies should be prioritized over pembrolizumab in never-smokers.

Impact of Including Carer Information in Time Trade-Off Tasks: Results from a Pilot Study.

INTRODUCTION: Carer quality of life (QoL) can be included in economic evaluations and captured using EQ-5D. Traditional valuation tasks require participants to imagine living in a health state for a number of years, without being told what to consider. This pilot study sought to investigate whether participants implicitly consider the impact of the health state on others, and the extent to which this may impact health state valuations. METHODS: Composite time trade-off (TTO) interviews were conducted with a convenience sample. Each interview included a 'traditional' TTO exercise to value three health states, and a 'combined' TTO exercise, where participants valued the same health states again, having been informed that they would require a carer living in a particular health state. Qualitative feedback was collected after each exercise. Paired t-test comparisons of the utilities elicited in each exercise were made. RESULTS: Thirty-three participants enrolled in the pilot. Mean differences between exercises were not statistically significant and differed in direction, although considerable heterogeneity was observed in individual response trajectories. Overall, 36% (n = 12) of participants expressed an unprompted concern about being a burden on others in the traditional exercise, and 67% (n = 22) of participants would have responded differently had the carer been in full health in the combined exercise. CONCLUSION: Providing contextual information about carers may impact valuations. Further research is required to better understand the reasons behind the variation in individual response trajectories observed in this pilot study. The insights from this study may be useful for informing the design of related future studies.

Keeping it real: implications of real-world treatment outcomes for first-line immunotherapy in metastatic non-small-cell lung cancer.

Tweetable abstract Recent RWD studies suggest that the performance of immunotherapy in NSCLC is not as good as that seen in RCTs. However, analyses using RWD (and their interpretation) require careful appraisal and quantification of possible sources of bias.

Assessment of Alectinib vs Ceritinib in ALK-Positive Non-Small Cell Lung Cancer in Phase 2 Trials and in Real-world Data.

Importance: Quantitative assessment of bias from unmeasured confounding and missing data can help evaluate uncertainty in findings from indirect comparisons using real-world data (RWD). Objective: To compare the effectiveness of alectinib vs ceritinib in terms of overall survival (OS) in patients with ALK-positive, crizotinib-refractory, non-small cell lung cancer (NSCLC) and to assess the sensitivity of these findings to unmeasured confounding and missing data assumptions. Design, Setting, and Participants: This comparative effectiveness research study compared patients from 2 phase 2 alectinib trials and real-world patients. Patients were monitored from June 2013 to March 2020. Comparisons of interest were between alectinib trial data vs ceritinib RWD and alectinib RWD vs ceritinib RWD. RWD treatment groups were selected from nationally representative cancer data from US cancer clinics, the majority from community centers. Participants were ALK-positive patients aged 18 years or older with advanced NSCLC, prior exposure to crizotinib, and Eastern Cooperative Oncology Group Performance Status (PS) of 0 to 2. Data analysis was performed from October 2020 to March 2021. Exposures: Initiation of alectinib or ceritinib therapy. Main Outcomes and Measures: The main outcome was OS. Results: In total, there were 355 patients: 183 (85 men [46.4%]) in the alectinib trial, 91 (43 men [47.3%]) in the ceritinib RWD group, and 81 (38 men [46.9%]) in the alectinib RWD group. Patients in the alectinib trial were younger (mean [SD] age, 52.53 [11.18] vs 57.97 [11.71] years), more heavily pretreated (mean [SD] number of prior therapy lines, 1.95 [0.72] vs 1.47 [0.81]), and had more favorable baseline ECOG PS (ECOG PS of 0 or 1, 165 patients [90.2%] vs 37 patients [77.1%]) than those in the ceritinib RWD group. The alectinib RWD group (mean [SD] age, 58.69 [11.26] years) had more patients with favorable ECOG PS (ECOG PS of 0 or 1, 49 patients [92.4%] vs 37 patients [77.1%]) and more White patients (56 patients [72.7%] vs 53 patients [62.4%]) compared with the ceritinib group. Compared with ceritinib RWD, alectinib-exposed patients had significantly longer OS in alectinib trials (adjusted hazard ratio [HR], 0.59; 95% CI, 0.44-0.75; P < .001) and alectinib RWD (HR, 0.46; 95% CI, 0.29-0.63; P < .001) after adjustment for baseline confounders. For the worst-case HR estimate of 0.59, residual confounding by a hypothetical confounder associated with mortality and treatment by a risk ratio greater than 2.24 was required to reverse the findings. Conclusions were robust to plausible deviations from random missingness for missing ECOG PS and underrecorded comorbidities and central nervous system metastases in RWD. Conclusions and Relevance: Alectinib exposure was associated with longer OS compared with ceritinib in patients with ALK-positive NSCLC, and only substantial levels of bias examined reversed the findings. These findings suggest that quantitative bias analysis can be a useful tool to address uncertainty of findings for decision-makers considering RWD.

Incidence and risk for acute hepatitis C infection during imprisonment in Australia.

To determine hepatitis C incidence and the demographic and behavioural predictors in seronegative drug injecting prisoners. Prisoners in New South Wales, Australia who: were aged 18 years and over; reported IDU; had been continuously imprisoned; had a documented negative HCV antibody test result in prison in the last 12 months; provided written informed consent. Subjects were interviewed about their demographic characteristics and detailed risk factors for transmission prior to, and since, imprisonment. A blood sample was collected to screen for HCV antibodies by ELISA and RNA by PCR. Of 253 inmates recruited, 120 were continuously imprisoned and included in this analysis. Sixteen acquired HCV infection indicating an incidence of 34.2 per 100 person years (CI: 19.6-55.6). Risk factors for transmission included prior imprisonment, methadone treatment and greater than 10 years of education. Although the frequency of injecting was reduced in prison, 33.6% continued to inject drugs, most commonly methamphetamine, and 90% of these reported sharing injecting equipment. Prison inmates were at high risk of HCV infection, despite some reduction in high-risk behaviours and access to prevention services. To prevent HCV transmission in prisons, better prevention strategies are required.

Incidence of primary hepatitis C infection and risk factors for transmission in an Australian prisoner cohort.

BACKGROUND: Hepatitis C virus (HCV) infection is common in prisoner populations, particularly those with a history of injecting drug use (IDU). Previous studies of HCV incidence have been based on small case numbers and have not distinguished risk events in prison from those in the community. METHODS: HCV incidence was examined in a longitudinal cohort of 488 Australian prisoners with a history of IDU and documented to be seronegative within 12 months prior to enrollment. Inmates were tested for anti-HCV antibodies and viremia, and interviewed about demographic and behavioral risk factors for transmission. RESULTS: The cohort was predominantly male (65%) with high rates of prior imprisonment (72%) and tattooing (73%), as well as longstanding IDU (mean 8.5 years). Ninety-four incident HCV cases were identified (incidence 31.6 per 100 person years). Independent associations were observed between incident infection and prior imprisonment (p = 0.02) and tattooing (p = 0.03), and surprisingly also with methadone maintenance treatment (MMT) (p < 0.001). CONCLUSIONS: High rates of new HCV infection were found in this prisoner cohort reflecting their substantive risk behavior profile, despite having remained uninfected for many years. The association with MMT is challenging and highlights the need for better understanding of prison-specific HCV transmission risks, as well as the uptake and effectiveness of prevention programs.

Injection of medications used in opioid substitution treatment in Australia after the introduction of a mixed partial agonist-antagonist formulation.

OBJECTIVES: To examine the levels and predictors of injection of buprenorphine-naloxone (BNX)--a combination of a partial opioid agonist and an opioid antagonist for treating opioid dependence--which was specifically developed to limit injecting. Comparison was made with injecting of two other opioid substitution treatment medications, methadone and buprenorphine (BPN); severe harms have been documented after injection of the latter. DESIGN AND PARTICIPANTS: Injecting was studied in regular injecting drug users ("IDUs") and current opioid substitution treatment clients ("clients"). Regular IDUs are interviewed annually in each Australian capital city (about 900 per year) and data for 2003-2007 were used; 399 clients were interviewed in 2007. Data on injection of opioid substitution treatment medications between 2003 and 2007 were adjusted for availability of medications (from national sales data for methadone, BPN and BNX). Predictors of injecting were analysed by multiple regression analyses. SETTING: Capital cities of all Australian states and territories. MAIN OUTCOME MEASURE: Injection of opioid substitution treatment medications among individuals both in and out of treatment. RESULTS: In the year after its introduction in Australia, BNX was injected less frequently and by fewer regular IDUs and clients compared with BPN, particularly when differences in the availability of medications were taken into account. Some individuals did nonetheless regularly inject BNX. Injection of methadone, BPN and BNX was more likely to occur among those injecting other pharmaceutical opioids. CONCLUSIONS: A partial opioid agonist-antagonist combination appears to be less commonly and less frequently injected by clients in treatment and IDUs who are not. Further studies are needed to evaluate longer-term trends in use and harms.