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.
Keywords: health technology assessment; immunotherapy; innovation; life expectancy; oncology; option value.