The Option Value of Innovative Treatments for Metastatic Melanoma

Background Treatment options in oncology have increased in recent years due to the quick pace of innovation. In the cancer care landscape, therapies that enable patients to live to the next innovation have additional value, “option value,” from the benefit of surviving to the next innovation. In such disease areas, providers and payers should consider this value when gauging the value of new therapies. The purpose of this study is to develop a model to estimate the additional survival patients attain from a therapy that allows them to live to benefit from further advances in care, and to apply the model to immunotherapy for metastatic melanoma. Methods The benefit of a therapy extends beyond immediate tumor control; it can also allow patients to live to benefit from further advances in care. This is a therapy’s option value. Using data from the SEER cancer registry and clinical trial publications, we developed a model to estimate option value and applied it to ipilimumab, the first immune checkpoint modulator used to treat metastatic melanoma. Because ipilimumab extends survival, select patients benefited from survival extension to live to benefit from the introduction of PD-1 inhibitors (i.e. pembrolizumab and nivolumab). We calculated the option value of ipilimumab in terms of additional life-months patients gained by living to become potential candidates for PD-1 inhibitors, discounting at 3% per year. Results Patients taking ipilimumab as a second-line therapy for metastatic melanoma gained 10.5 months compared to patients taking the prior standard of care. Patients diagnosed in 2011, 2012, and 2013 gained an additional 1.6, 2.8, and 5.1 months of life expectancy, respectively, by living to see the introduction of PD-1 inhibitors. This equates to an option value of 15%, 27%, and 49%, respectively, of the conventionally calculated survival gain from ipilimumab. Ipilimumab had greater option value for patients diagnosed in later years who were more likely to live to the introduction of PD-1 inhibitors. Conclusions Therapies that enable patients to see further advances in care have option value. Option value is particularly important to patients with disease areas undergoing rapid innovation.

Cancer survival extension from drug treatments

Cancer causes one in four of all deaths in the UK. Advances in biologic and pharmaceutical therapies over recent years have increased achievable survival gain in most life-limiting cancers, ranging from modest incremental improvements to step changes in life expectancy. The realised and anticipated impact of treatment advances on survival is of wide-ranging interest, from informing decisions about healthcare to understanding influences on mortality trends. This paper presents an overview of evidence for survival extension from a range of therapies that have become available in recent years for the treatment of lung, colorectal and breast cancer. The evidence considered includes short-term empirical evidence from clinical trials as well as longer-term estimates from models extrapolating over a lifetime horizon. The core data source is the evidence base supporting guidance published by the National Institute for Health and Care Excellence (NICE), UK. This evidence has already been subject to appraisal by NICE; the aim of this paper is to collate the existing estimates submitted to NICE in order to appreciate the wide range in survival extension resulting from systematically identified cancer treatments.

E. coli hypoxia-inducible factor ArcA mediates lifespan extension in a lipoic acid synthase mutant by suppressing acetyl-CoA synthetase

We have previously shown that both the hypoxia-inducible transcription factor ArcA and the PoxB/Acs bypass of the pyruvate dehydrogenase complex contribute to extended lifespan in Escherichia coli. In agreement with studies in higher eukaryotes, we also demonstrated that long-lived E. coli mutants, including LipA-deficient cells, are stress resistant. Here, we show that ArcA contributes to the enhanced lifespan and heat shock resistance of the lipA mutant by suppressing expression of the acetyl-CoA synthetase (acs) gene. The deletion of acs reversed the reduced lifespan of the lipA arcA mutant and promoted the accumulation of extracellular acetate, indicating that inhibition of carbon source uptake contributes to survival extension. However, Acs also sensitized cells lacking ArcA to heat shock, in the absence of extracellular acetate. These results provide evidence for the role of Acs in regulating lifespan and/or stress resistance by both carbon source uptake-dependent and -independent mechanisms.

SOD2 Functions Downstream of Sch9 to Extend Longevity in Yeast

Signal transduction pathways inactivated during periods of starvation are implicated in the regulation of longevity in organisms ranging from yeast to mammals, but the mechanisms responsible for life-span extension are poorly understood. Chronological life-span extension in S. cerevisiae cyr1 and sch9 mutants is mediated by the stress-resistance proteins Msn2/Msn4 and Rim15. Here we show that mitochondrial superoxide dismutase (Sod2) is required for survival extension in yeast. Deletion of SOD2 abolishes life-span extension in sch9Δ mutants and decreases survival in cyr1:mTn mutants. The overexpression of Sods—mitochondrial Sod2 and cytosolic CuZnSod (Sod1)—delays the age-dependent reversible inactivation of mitochondrial aconitase, a superoxide-sensitive enzyme, and extends survival by 30%. Deletion of the RAS2 gene, which functions upstream of CYR1, also doubles the mean life span by a mechanism that requires Msn2/4 and Sod2. These findings link mutations that extend chronological life span in S. cerevisiae to superoxide dismutases and suggest that the induction of other stress-resistance genes regulated by Msn2/4 and Rim15 is required for maximum longevity extension.