Most drug discovery efforts today treat the cell as a black box and the underlying biochemical machinery as "the ghost in the machine." There are numerous examples of failures in the drug discovery process resulting from such a lack of knowledge. For cancer and other human diseases, it is often known what critical pathways are involved but not how to identify small molecules active against specific pathways. A rational solution to drug discovery requires the ability to rapidly identify small molecules that act in defined ways to restore the circuitry of the healthy cell, and do not have unintended (off-pathway) side effects.

Cancer cells have defects in regulatory circuits that govern normal cell proliferation and homeostasis. A pathway-based approach to cancer drug discovery involves identifying molecules that act in desired ways against specific regulatory circuits; in effect, re-wiring the circuitry of the cancer cell. The approach is both rational - taking advantage of the existing vast body of knowledge in order to craft a pathway-based discovery approach - and efficient. The efficiency results from several key elements of the strategy:

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 It is not necessary to rely on a priori judgments about the drugability of specific targets. Rather, small molecules can be screened against entire pathways, followed by precise identification of the target of the active molecule.
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 A limited number of screens can be constructed that represent the majority of the disease-related pathways, allowing screening to proceed quickly.
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 The results of small molecule screening can be tested in phenotypic assays for comparison with existing therapeutic agents.
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 Novel, rational approaches including combination therapies (hitting more than one disease pathway simultaneously) can be tested rapidly once the active small molecules are in hand.

At Odyssey Thera, the processes of target validation, high throughput screening, biological activity and drug specificity are combined in live cell assays, allowing drug discovery to proceed at an unprecedented rate. Importantly, the mechanism of action of known and unknown drugs can be assessed, identifying undesired, off-pathway effects early in the process (see Pharmacological Profiling).