Potential therapeutic targets identified
in discovery research are confirmed to
play a causative role in a given disease.
Target to hit.
Large numbers of chemical or
biological agents are screened to
identify molecules that “hit” the target.
Hit to lead.
Positive hits are further tested to
determine which bind the target
with the most specificity.
The properties of the lead compound
are refined to enhance potency and drug
availability and to reduce side effects.
Cellular and animal models are used to test for
effectiveness of the optimized lead, identify
any potential toxicity issues, and determine an
optimal starting dose for clinical or “
first-in-human” testing. The final compound is called
the clinical candidate.
Investigational new drug (IND).
Prior to clinical testing, one or more clinical
candidates are submitted to the FDA for
approval to be used in clinical trials.
Adapted from ( 1)