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)