Simulated physician personas can tell you what an individual HCP believes. What they cannot tell you is what happens when thousands of physicians, patients, payers, and competitors interact with each other over time — and that is the question commercial teams actually need answered. Market Simulator, the simulation module inside Sagan Agents, is built around this distinction: moving beyond individual persona outputs to simulated market outcomes, where the result is not a synthetic survey response but a projected prescribing share, an uptake curve, or a forecast of how a competitive launch reshapes your market over eight quarters.
The traditional approach to commercial scenario planning involves primary research and forecasting as two separate disciplines with a handoff between them. Market research captures physician perceptions and intent. A separate forecasting team then converts those research outputs into a market model — a process that adds another four to six weeks after fielding closes. A competitor data readout lands on a Friday; the insights team spends two weeks designing a study; the study takes six to eight weeks to field; the forecasting team takes another month to translate the findings into a projection; by the time a number reaches the brand team, the market has already responded. The organization made its decisions without the data.
Market Simulator is designed to collapse that gap. It is a system-level simulation engine where the question shifts from "what do physicians say they intend to do?" to "what happens in the market if we do X?" — and the answer arrives in hours, not months.
Market Simulator is structured in four layers that work together to produce dynamic, explainable simulations. The first layer, Market Physics, establishes the structural backbone: patient flows across lines of therapy grounded in claims data, formulary friction from payer databases, competitive positioning, and rep reach from CRM activity. These are the rules every agent operates within. The second layer, the Belief State Engine, maintains the explicit cognitive state of each HCP and patient agent: perceived efficacy, safety concerns, switching inertia, cost sensitivity, and evidence confidence — each stored as an updateable variable rather than a static attribute.
The third layer, Signal Interpretation, is where large language models operate narrowly and specifically: when a new clinical message or competitive data readout arrives, the LLM classifies it into structured signal features — novelty, credibility, valence, resistance — then hands those features to the Belief State Engine, which applies calibrated response curves to convert them into numeric belief changes. Standard recurring events bypass this layer entirely and update beliefs through deterministic promotional response models. The fourth layer, the Decision and Learning Layer, is where agents act and adapt: choice probabilities emerge from current belief states and market constraints, agents act, outcomes are observed, and reinforcement feeds back into beliefs — so the simulated market evolves organically over the simulation horizon.
The most immediate use case is competitive scenario planning. When a competitor event occurs — a new data readout, a label expansion, a payer win — Market Simulator models how that event propagates through physician networks and affects brand preference across segments and geographies. War-gaming scenarios that previously required weeks of study design and fielding run in hours, with outputs grounded in actual claims-based prescribing patterns rather than general-purpose market analogs.
For launch planning, Market Simulator produces pre-launch uptake curves across physician segments and lines of therapy, incorporating access friction, peer influence dynamics, and evidence adoption patterns calibrated to analogous historical launches. Field force reallocation analysis shows how changes to rep targeting rules or call plan parameters shift prescribing behavior across regions before resources are committed. Market trend modeling simulates how structural shifts — guideline updates, payer policy changes, treatment paradigm evolution — create divergent futures under different strategic assumptions.
What separates Market Simulator from generic pharmaceutical digital twin tools is the calibration layer. Simulated agent parameters are not generated from pattern-matching on third-party survey archives or public behavioral data. They are initialized against the client's own internal data — claims extracts, regional sales performance, CRM and field force activity, and the full primary research corpus — then continuously updated as the market evolves. ZoomRx's ongoing primary research through a 60,000-plus HCP panel provides the attitudinal calibration layer: the behavioral and perceptual data that makes agent belief states reflect actual physician cognition rather than assumed cognition.
The projected outcome, based on the platform's architecture and deployment design, is 10x faster scenario testing. Commercial teams can run comprehensive multi-variable analyses in the time traditionally required to design, field, and analyze a single primary research study — with outputs grounded in data the organization has already paid for.
For a closer look at how Market Simulator fits into the Sagan Agents platform or to discuss a specific use case for your commercial team, connect with Us.