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ActivityDiff: A diffusion model with Positive and Negative Activity Guidance for De Novo Drug Design
Huimin Zhu1, Renyi Zhou1, Jing Tang2
1School of Computer Science and Engineering, Central South University, Changsha 410083, China.
ActivityDiff uses positive and negative guidance to design molecules with desired activity and reduced off-target effects. This approach enhances drug safety and selectivity by explicitly considering both beneficial and harmful interactions.
Area of Science:
- Computational chemistry
- Drug discovery
- Artificial intelligence in medicine
Background:
- De novo drug design aims to optimize target activity while minimizing off-target interactions for safety and selectivity.
- Current generative models often neglect negative activity data, hindering the suppression of undesired effects.
- Off-target interactions are a major cause of drug attrition and adverse events.
Purpose of the Study:
- To introduce ActivityDiff, a novel framework for activity-controlled molecular generation.
- To integrate both positive and negative guidance for improved drug design.
- To enhance the safety and efficacy of generated drug candidates.
Main Methods:
- Developed a classifier-guided diffusion framework named ActivityDiff.
- Incorporated separately trained drug-target classifiers for positive and negative guidance.
- Utilized explicit negative guidance to suppress harmful off-target interactions during generation.
Main Results:
- ActivityDiff successfully generated molecules for single- and dual-target design tasks.
- The framework supported fragment-constrained dual-target generation and selective generation for specificity.
- Demonstrated significant reduction in off-target effects, improving overall drug safety.
- Showcased the effectiveness of negative guidance in jointly optimizing efficacy and safety.
Conclusions:
- Classifier-guided diffusion with explicit negative guidance is an effective strategy for molecular design.
- ActivityDiff enables simultaneous optimization of desired activity and minimization of off-target effects.
- This approach represents a significant advancement in developing safer and more selective drug candidates.
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