Prediction markets — platforms where users buy and sell shares on future event outcomes — have officially entered the pharmaceutical space, and healthcare experts are sounding the alarm. Platforms like Kalshi and Polymarket now offer contracts on clinical trial endpoints, including whether specific drugs will meet their primary outcomes. Brown University health policy professor Matthew Vogel and colleagues flagged the trend in a New England Journal of Medicine perspective, calling it "unknown territory."

The core concern? Clinical trial integrity. Unlike betting on sports scores, wagering on drug trials creates financial incentives that could influence the behavior of both participants and researchers. High or low market odds could sway patients' decisions to enroll — or drop out — of trials, undermining the equipoise that valid research requires. Inaccurate market predictions could also mislead patients about their personal likelihood of benefiting from a treatment.

By the Numbers:

• $50 billion in prediction market trading volume in 2025
• Kalshi is already offering contracts on large, late-stage trial endpoints and considering expanding to earlier-phase trials and adverse event counts

Why it matters: Vogel and colleagues are calling on the FDA and the U.S. Commodity Futures Trading Commission to establish transparent regulations — including pre-trade review of clinical trial contracts and restrictions on betting tied to easily manipulated metrics like adverse event reports. Without guardrails, the booming prediction market industry could quietly reshape how clinical trials are conducted and perceived.