MIT and Recursion Release Boltz-2: Next Generation AI Model to Predict Binding Affinity at Unprecedented Speed, Scale, and Accuracy
- Boltz-2 is the first biomolecular co-folding model to combine structure and binding affinity prediction, approaching the accuracy of physics-based free energy perturbation (FEP) calculations but at speeds up to 1000x faster in standard benchmarks
- The development of this open source model for academic and commercial use was a collaborative effort, combining MIT’s deep academic expertise with Recursion's AI research and NVIDIA-accelerated supercomputer, BioHive-2
“Accurately predicting how strongly molecules bind has been a long-standing challenge in drug discovery—one that required novel machine learning and computer science techniques to address,” said
Specifically, Boltz-2 marks a new era for in silico screening, in standard benchmarks approaching the accuracy of physics-based free energy perturbation (FEP), an industry-standard computational method used to predict the binding affinity of molecules, at speeds up to 1000x faster. The decrease in cost and increase in speed and scale makes large-scale and accurate virtual screening more practical than previously possible, directly addressing a critical bottleneck in small molecule discovery.
"Selecting the right molecules early is one of the most fundamental challenges in drug discovery, with implications for whether R&D programs succeed or fail," said
Below are key components and differentiators of Boltz-2 vs other methods of predicting biomolecular structures and affinities:
- Improved Affinity Prediction: Near-FEP accuracy on the widely adopted FEP+ benchmark while being over 1,000 times faster and less computationally expensive
- Leading Benchmark Performance: Superior predictive power, demonstrating outperformance over all CASP16 affinity challenge participants
- Advanced Joint Modeling: Uniquely models 3D complex structures while jointly predicting binding affinity and protein dynamics (e.g., B-factors)
- Controllable & Physically Realistic: Achieves significantly improved physical plausibility using Boltz-steering and offers enhanced user control via template, method, and contact conditioning
- Novel & Expanded Training Data: Trained on molecular dynamics simulations, expanded distillation data, and approximately 5 million binding affinity assay measurements
In line with
Boltz-2’s development was led by the Boltz team at
About Recursion
Recursion (NASDAQ: RXRX) is a clinical stage TechBio company leading the space by decoding biology to radically improve lives. Enabling its mission is the Recursion OS, a platform built across diverse technologies that continuously generate one of the world’s largest proprietary biological and chemical datasets. Recursion leverages sophisticated machine-learning algorithms to distill from its dataset a collection of trillions of searchable relationships across biology and chemistry unconstrained by human bias. By commanding massive experimental scale — up to millions of wet lab experiments weekly — and massive computational scale — owning and operating one of the most powerful supercomputers in the world, Recursion is uniting technology, biology and chemistry to advance the future of medicine.
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