FDA Sets Efficacy Threshold for Obesity Therapies Amid Market Expansion

Efficacy Threshold:
The FDA has proposed a minimum of 5% weight loss as the efficacy threshold for investigational obesity therapies, which must be statistically significant after 1 year of treatment at the maintenance dose1.

Market Dynamics:
The obesity market is expected to continue its rapid growth, with 2025 being a pivotal year for competitive dynamics, innovation, and reimbursement trends. The global spend on anti-obesity medications (AOMs) exceeded $30 billion in 2024, driven by the rollout of Novo Nordisk’s semaglutide and Lilly’s tirzepatide2.

Safety Assessments:
The FDA guidance emphasizes the need for comprehensive safety assessments, including cardiovascular evaluations, neuropsychiatric evaluations, and testing for immunogenic potential1.

Comparison to Existing Therapies:
The proposed 5% threshold is lower than the weight loss achieved by already-approved therapies like Novo’s Wegovy (10% to 15%) and Lilly’s Zepbound (10% to 18%)1.

Future Market Projections:
The global AOM market is forecasted to grow to $100 billion by 2030, driven by increasing obesity rates and the development of more effective treatments like GLP-1 receptor agonists5.

Sources:

1. https://www.biospace.com/fda/fda-proposes-setting-bar-for-weight-loss-therapies-as-obesity-space-heats-up

2. https://www.iqvia.com/locations/emea/blogs/2025/01/outlook-for-obesity-in-2025-more-than-a-transition-year

5. https://www.goldmansachs.com/insights/articles/anti-obesity-drug-market