Designing Better Therapeutics, Atom by Atom

Psivant Therapeutics is advancing a paradigm shift in biotechnology by pioneering a physics-driven approach to drug design that is tightly coupled to chemistry and biology research and development. Our QUAISAR platform is purpose-built to discover novel small molecule therapeutics to address biologically and genetically validated, but previously intractable, protein targets.

Hypothesis & Ideation

Simulations identify binding hotspots, induced pockets, and optimizable regions. All hypotheses are tracked for measuring progress toward TPP and continual improvements.


Reaction-based enumeration, molecular breeding, and generative modeling explore chemical space based on  a specified hypothesis.  Our curated chemical building block database ensures that the chemical constituents can be purchased to synthesize the enumerated molecules.

Fingerprint Filters

Enumerated chemical space is reduced based on drug-likeness and chemical similarity.  These fast calculations eliminate the most unsuitable molecules.

Property Filters

In-house QSAR models using proprietary curated datasets predict ADME properties such as solubility, permeability, hERG, and clearance. Only the most suitable molecules progress past this stage.

Structure-Based Filters

Docking, shape overlap, and contact maps account for general fit to the protein pocket and desirable interactions based on design hypotheses.

Quick Simulations

Short MD simulations and MM-GBSA account for light protein flexibility, protein-ligand interactions, and desolvation. This step eliminates enough molecules for us to move into rigorous free energy simulations.

Rigorous Simulations

Rigorous binding free energy simulations account fully for the thermodynamic contributions to binding (enthalpy and entropy). Additionally, advanced MD techniques are applied when long-timescale motions are involved, such as allosteric modulation and signaling.

Synthesis and Assays

Molecules are prioritized based on a multi-parameter analysis guided by the TPP. Synthetic accessibility, time to results, and costs are also accounted for. Synthesized compounds are progressed through the assay cascade.


Data is collected, analyzed, and discussed to determine the focus of the next iteration. All data is tracked in our Project Dashboard, with real-time monitoring and reporting of project data. Progression toward TPP is visible through our organization to ensure transparent data-driven decisions.