Emergency deployment of direct air capture as a response to the climate crisis.

Though highly motivated to slow the climate crisis, governments may struggle to impose costly polices on entrenched interest groups, resulting in a greater need for negative emissions. Here, we model wartime-like crash deployment of direct air capture (DAC) as a policy response to the climate crisis, calculating funding, net CO2 removal, and climate impacts. An emergency DAC program, with investment of 1.2-1.9% of global GDP annually, removes 2.2-2.3 GtCO2 yr-1 in 2050, 13-20 GtCO2 yr-1 in 2075, and 570-840 GtCO2 cumulatively over 2025-2100. Compared to a future in which policy efforts to control emissions follow current trends (SSP2-4.5), DAC substantially hastens the onset of net-zero CO2 emissions (to 2085-2095) and peak warming (to 2090-2095); yet warming still reaches 2.4-2.5 °C in 2100. Such massive CO2 removals hinge on near-term investment to boost the future capacity for upscaling. DAC is most cost-effective when using electricity sources already available today: hydropower and natural gas with renewables; fully renewable systems are more expensive because their low load factors do not allow efficient amortization of capital-intensive DAC plants.

Comparing the Evolution of Risk Culture in Radiation Oncology, Aviation, and Nuclear Power.

OBJECTIVES: All organizations seek to minimize the risks that their operations pose to public safety. This task is especially significant if they deal with complex or hazardous technologies. Five decades of research in quantitative risk analysis have generated a set of risk management frameworks and practices that extend across a range of such domains. Here, we investigate the risk culture in three commercial enterprises that require exceedingly high standards of execution: radiation oncology, aviation, and nuclear power. METHODS: One of the characteristics of high reliability organizations is their willingness to learn from other such organizations. We investigate the extent to which this is true by compiling a database of the major publications on risk within each of the three fields. We conduct a bibliographic coupling analysis on the combined database to identify connections among publications. This analysis reveals the strength of engagement across disciplinary boundaries and the extent of cross-adoption of best practices. RESULTS: Our results show that radiation oncology is more insulated than the other two fields in its adoption and propagation of state-of-the-art risk management tools and frameworks that have transformed aviation and nuclear power into high reliability enterprises with actuarially low risk. CONCLUSIONS: Aviation and nuclear power have established risk cultures that cross-pollinate. In both nature and extent, we found a distinct difference in radiation oncology's engagement with the risk community, and it lags behind the other two fields in implementing best practices that might mitigate or eliminate risks to patient safety.

Cost-effectiveness of second-line atezolizumab in Canada for advanced non-small cell lung cancer (NSCLC).

Aim: To assess the cost-effectiveness in Canada of atezolizumab compared with docetaxel or nivolumab for the treatment of advanced NSCLC after first-line platinum-doublet chemotherapy. Materials and methods: A three-state partitioned-survival model was developed. Clinical inputs were obtained from the phase III OAK trial comparing atezolizumab with docetaxel in patients with advanced NSCLC who progressed after first-line platinum-doublet chemotherapy. Overall survival (OS) and progression-free survival (PFS) were extrapolated beyond the trial period using parametric models. A cure model assuming a 1% cure fraction was fitted to the OS data for atezolizumab. Outcomes for nivolumab were informed by a network meta-analysis (NMA) vs atezolizumab. Resource use and costs were informed by clinical expert opinion and published Canadian sources. Utility values were obtained from the OAK trial. The perspective of the analysis was that of the Canadian publicly-funded healthcare system. The base case time horizon was 10 years, and the discount rate was 1.5% annually for both costs and effects. Scenario analyses were performed to test the robustness of the results and all analyses were performed probabilistically. Results: Atezolizumab demonstrated a quality-adjusted life-year (QALY) gain of 0.60 compared with docetaxel at an incremental cost of $85,073, resulting in an incremental cost-effectiveness ratio (ICER) of $142,074/QALY. Atezolizumab dominated nivolumab (regardless of dosing regimen), based on modest differences in both QALYs and costs. Docetaxel was most likely to be cost effective at willingness-to-pay (WTP) thresholds below $125,000/QALY gained, while atezolizumab was most likely to be cost effective beyond this WTP threshold. In most scenario analyses, the results remained robust to changes in parameters. A reduced time horizon and alternative approaches to the NMA had the greatest impact on cost-effectiveness results. Conclusion: Atezolizumab represents a cost-effective therapeutic option in Canada for the treatment of patients with advanced NSCLC who progress after first-line platinum doublet chemotherapy.

Systematic review of health state utility values in metastatic non-small cell lung cancer with a focus on previously treated patients.

BACKGROUND: Health state utility values (HSUVs) are an important input to economic evaluations and the choice of HSUV can affect the estimate of relative cost-effectiveness between interventions. This systematic review identified utility scores for patients with metastatic non-small cell lung cancer (mNSCLC), as well as disutilities or utility decrements relevant to the experience of patients with mNSCLC, by treatment line and health state. METHODS: The MEDLINE®, Embase and Cochrane Library databases were systematically searched (September 2016) for publications describing HSUVs in mNSCLC in any treatment line. The EQ-5D website, the School of Health and Related Research Health Utilities Database (ScHARRHUD) and major pharmacoeconomic and clinical conferences in 2015-2016 were also queried. Studies in adults with previously treated mNSCLC were selected for further analysis. The information extracted included study design, description of treatment and health state, respondent details, instrument and tariff, HSUV or (dis) utility decrement estimates, quality of study, and appropriateness for use in economic evaluations. RESULTS: Of 1883 references identified, 36 publications of 34 studies were included: 19 reported EQ-5D scores; eight reported HSUVs from valuations of vignettes made by members of the public using standard gamble (SG) or time trade-off (TTO); two reported SG or TTO directly elicited from patients; two reported EQ-5D visual analogue scale scores only; one reported Assessment of Quality of Life instrument scores; one reported HSUVs for caregivers to patients with mNSCLC using the 12-item Short-Form Health Survey; and one estimated HSUVs based on expert opinion. The range of HSUVs identified for comparable health states showed how differences in study type, tariff, health state and the measures used can drive variation in HSUV estimates. CONCLUSIONS: This systematic review provides a set of published HSUVs that are relevant to the experience of adult patients previously treated for mNSCLC. Our review begins to address the challenge of identifying reliable estimates of utility values in mNSCLC that are suitable for use in economic evaluations, and also highlights how varying estimates result from differences in methodology.

Pegylated Liposomal Irinotecan Hydrochloride Trihydrate for Treating Pancreatic Cancer After Gemcitabine: An Evidence Review Group Perspective of a NICE Single Technology Appraisal.

The National Institute for Health and Care Excellence (NICE) invited the manufacturer (Shire Pharmaceuticals) of pegylated liposomal irinotecan hydrochloride trihydrate (liposomal irinotecan) to submit clinical and cost-effectiveness evidence for its use in combination with 5-fluorouracil (5-FU) and folic acid/leucovorin (LV) for treating patients with pancreatic cancer following prior treatment with gemcitabine as part of the institute's Single Technology Appraisal process. The Liverpool Reviews and Implementation Group at the University of Liverpool was commissioned to act as the Evidence Review Group (ERG). This article presents a summary of the company's evidence, the ERG review and the resulting NICE guidance (TA440), issued on 26 April 2017. Clinical evidence for liposomal irinotecan + 5-FU/LV versus 5-FU/LV was derived from 236 patients with metastatic pancreatic cancer in the multinational, open-label, randomised controlled NAPOLI-1 trial. Results from analyses of progression-free survival and overall survival showed statistically significant improvements for patients treated with liposomal irinotecan + 5-FU/LV compared with those treated with 5-FU/LV. However, 5-FU/LV alone is rarely used in National Health Service clinical practice for patients with metastatic pancreatic cancer previously treated with gemcitabine. The company, ERG and Appraisal Committee (AC) all agreed that oxaliplatin + 5-FU/LV is the most commonly used treatment. Oxaliplatin + 5-FU/LV was compared with 5-FU/LV in two trials identified by the company. However, the company and the ERG both considered attempts to compare the efficacy of liposomal irinotecan + 5-FU/LV with oxaliplatin + 5-FU/LV to be methodologically flawed; not only was there heterogeneity between trials and their populations but also the proportional hazards assumption required to conduct a robust indirect treatment comparison (ITC) was violated. Nonetheless, data derived from an ITC were used to inform the company's economic model. Using the discounted patient access scheme price for liposomal irinotecan + 5-FU/LV, the company reported an incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year (QALY) gained of £54,412 for the comparison with oxaliplatin + 5-FU/LV. The ERG considered that the company's base-case cost-effectiveness results for the comparison of liposomal irinotecan + 5-FU/LV versus oxaliplatin + 5-FU/LV were underestimates and should be interpreted with extreme caution. Following implementation of a number of model amendments, the ERG's modified exploratory ICER for the comparison of liposomal irinotecan + 5-FU/LV versus oxaliplatin + 5-FU/LV was £106,898 per QALY gained. The AC accepted the majority of the ERG's amendments to the model, and also highlighted that the total QALYs for oxaliplatin + 5-FU/LV were lower than for 5-FU/LV in the company's model, which the AC considered to be clinically implausible. The AC therefore considered results from exploratory analyses, undertaken by the ERG, which included altering the QALY difference between liposomal irinotecan + 5-FU/LV and oxaliplatin + 5-FU/LV by ± 10%. These analyses resulted in ICERs for the comparison of liposomal irinotecan + 5-FU/LV versus oxaliplatin + 5-FU/LV of between £201,019 per QALY gained to liposomal irinotecan + 5-FU/LV being dominated by oxaliplatin + 5-FU/LV. Therefore, despite uncertainty around the clinical-effectiveness evidence and cost-effectiveness results, the AC was confident that the ICER was in excess of £50,000 per QALY gained. The final guidance issued by NICE is that liposomal irinotecan + 5-FU/LV is not recommended within its marketing authorisation for treating metastatic adenocarcinoma of the pancreas in adults whose disease has progressed after gemcitabine-based therapy.

Talimogene Laherparepvec for Treating Metastatic Melanoma: An Evidence Review Group Perspective of a NICE Single Technology Appraisal.

The National Institute for Health and Care Excellence (NICE) invited the manufacturer (Amgen) of talimogene laherparepvec (T-VEC) to submit clinical and cost-effectiveness evidence for previously untreated advanced (unresectable or metastatic) melanoma as part of the Institute's Single Technology Appraisal process. The Liverpool Reviews and Implementation Group (LRiG) at the University of Liverpool was commissioned to act as the Evidence Review Group (ERG). This article presents a summary of the company's submission of T-VEC, the ERG review and the resulting NICE guidance (TA410), issued in September 2016. T-VEC is an oncolytic virus therapy granted a marketing authorisation by the European Commission for the treatment of adults with unresectable melanoma that is regionally or distantly metastatic (stage IIIB, IIIC and IVM1a) with no bone, brain, lung or other visceral disease. Clinical evidence for T-VEC versus granulocyte-macrophage colony-stimulating factor (GM-CSF) was derived from the multinational, open-label randomised controlled OPTiM trial [Oncovex (GM-CSF) Pivotal Trial in Melanoma]. In accordance with T-VEC's marketing authorisation, the company's submission focused primarily on 249 patients with stage IIIB to stage IV/M1a disease who constituted 57% of the overall trial population (T-VEC, n = 163 and GM-CSF, n = 86). Results from analyses of durable response rate, objective response rate, time to treatment failure and overall survival all showed marked and statistically significant improvements for patients treated with T-VEC compared with those treated with GM-CSF. However, GM-CSF is not used to treat melanoma in clinical practice. It was not possible to compare treatment with T-VEC with an appropriate comparator using conventionally accepted methods due to the absence of comparative head-to-head data or trials with sufficient common comparators. Therefore, the company compared T-VEC with ipilimumab using what it described as modified Korn and two-step Korn methods. Results from these analyses suggested that treatment with T-VEC was at least as effective as treatment with ipilimumab. Using the discounted patient access scheme (PAS) price for T-VEC and list price for ipilimumab, the company reported incremental cost-effectiveness ratios (ICERs) per quality-adjusted life-year (QALY) gained. For the comparison of treatment with T-VEC versus ipilimumab, the ICER per QALY gained was -£16,367 using the modified Korn method and -£60,271 using the two-step Korn method. The NICE Appraisal Committee (AC) agreed with the ERG that the company's methods for estimating clinical effectiveness of T-VEC versus ipilimumab were flawed and therefore produced unreliable results for modelling progression in stage IIIB to stage IVM1a melanoma. The AC concluded that the clinical and cost effectiveness of treatment with T-VEC compared with ipilimumab is unknown in patients with stage IIIB to stage IV/M1a disease. However, the AC considered that T-VEC may be a reasonable option for treating patients who are unsuitable for treatment with systemically administered immunotherapies (such as ipilimumab). T-VEC was therefore recommended by NICE as a treatment option for adults with unresectable, regionally or distantly metastatic (stage IIIB to stage IVM1a) melanoma that has not spread to bone, brain, lung or other internal organs, only if treatment with systemically administered immunotherapies is not suitable and the company provides T-VEC at the agreed discounted PAS price.

Evaluating the Cost, Safety, and Proliferation Risks of Small Floating Nuclear Reactors.

It is hard to see how our energy system can be decarbonized if the world abandons nuclear power, but equally hard to introduce the technology in nonnuclear energy states. This is especially true in countries with limited technical, institutional, and regulatory capabilities, where safety and proliferation concerns are acute. Given the need to achieve serious emissions mitigation by mid-century, and the multidecadal effort required to develop robust nuclear governance institutions, we must look to other models that might facilitate nuclear plant deployment while mitigating the technology's risks. One such deployment paradigm is the build-own-operate-return model. Because returning small land-based reactors containing spent fuel is infeasible, we evaluate the cost, safety, and proliferation risks of a system in which small modular reactors are manufactured in a factory, and then deployed to a customer nation on a floating platform. This floating small modular reactor would be owned and operated by a single entity and returned unopened to the developed state for refueling. We developed a decision model that allows for a comparison of floating and land-based alternatives considering key International Atomic Energy Agency plant-siting criteria. Abandoning onsite refueling is beneficial, and floating reactors built in a central facility can potentially reduce the risk of cost overruns and the consequences of accidents. However, if the floating platform must be built to military-grade specifications, then the cost would be much higher than a land-based system. The analysis tool presented is flexible, and can assist planners in determining the scope of risks and uncertainty associated with different deployment options.

Expert assessments of the cost of light water small modular reactors.

Analysts and decision makers frequently want estimates of the cost of technologies that have yet to be developed or deployed. Small modular reactors (SMRs), which could become part of a portfolio of carbon-free energy sources, are one such technology. Existing estimates of likely SMR costs rely on problematic top-down approaches or bottom-up assessments that are proprietary. When done properly, expert elicitations can complement these approaches. We developed detailed technical descriptions of two SMR designs and then conduced elicitation interviews in which we obtained probabilistic judgments from 16 experts who are involved in, or have access to, engineering-economic assessments of SMR projects. Here, we report estimates of the overnight cost and construction duration for five reactor-deployment scenarios that involve a large reactor and two light water SMRs. Consistent with the uncertainty introduced by past cost overruns and construction delays, median estimates of the cost of new large plants vary by more than a factor of 2.5. Expert judgments about likely SMR costs display an even wider range. Median estimates for a 45 megawatts-electric (MWe) SMR range from $4,000 to $16,300/kWe and from $3,200 to $7,100/kWe for a 225-MWe SMR. Sources of disagreement are highlighted, exposing the thought processes of experts involved with SMR design. There was consensus that SMRs could be built and brought online about 2 y faster than large reactors. Experts identify more affordable unit cost, factory fabrication, and shorter construction schedules as factors that may make light water SMRs economically viable.