PURPOSE: The workshop will demonstrate how concepts from traditional pharmacoeconomic (PE) models can be brought together to predict future market outlooks and to estimate the size of key patient segments/categories within the evolving market given the anticipated changes in treatments and populations. The workshop will introduce the framework of the modeling approach that utilizes key features of traditional PE models, and hands-on experience in developing a simple model for a hypothetical case example. DESCRIPTION: Understanding how a therapeutic area may evolve under anticipated market disruptions -such as availability of new therapies, treatment guideline changes, shifts in populations and therapy preferences etc.- and its implications on sizes of addressable patient segments/categories has been a key strategic question for decision makers. Due to rapid evolution of healthcare market, such assessments are becoming more important, and more complex. Forecasting models that look at patient populations at an aggregate level and simplify market dynamics due to their structural limitations typically fail to capture important market nuances, hence lack meaningful insights that can be used to improve decision making. For most therapeutic areas, an alternative approach that leverages core features of traditional PE models (e.g., cost-effectiveness and budget impact analyses) can enable analysts to incorporate future market developments and explore their longer term implications in a transparent way, in addition to providing the flexibility to incorporate existing management paradigms. The workshop will start with a high-level description of the decision problem and the inputs and outputs of typical forecasting models used today. Then, methodological requirements for a model that can capture complexities of the evolving market will be presented and discussed. A few specific examples will be shared. Finally, attendees will be asked to participate in designing a forecasting model to explore potential market evolution scenarios for a hypothetical disease area under pre-specified market developments.