Telotristat (telotristat etiprate) is an ethyl ester prodrug which is hydrolyzed to its active moiety LP-778902 both in vivo and in vitro. Telotristat etiprate is an orally bioavailable, small-molecule, tryptophan hydroxylase (TPH) inhibitor. It is the first investigational drug in clinical studies to target TPH, an enzyme that triggers the excess serotonin production within metastatic neuroendocrine tumor (mNET) cells leading to carcinoid syndrome. Unlike existing treatments of carcinoid syndrome which reduce the release of serotonin outside tumor cells, telotristat etiprate reduces serotonin production within the tumor cells. By specifically inhibiting serotonin production telotristat may provide patients with more control over their disease. Telotristat etiprate has received Fast Track and Orphan Drug designation from the U.S. Food and Drug Administration and has been granted priority review by the FDA with a Prescription Drug User Fee Act (PDUFA) target action date of February 28, 2017.

Carafiban is orally active heterocyclic peptide mimetics fibrinogen IIb/IIIa receptor antagonist with antithrombotic activity. Carafiban is a prodrug, that underwent metabolic transformation to active metabolite des-ethyl- Carafiban, that inhibited dose-dependently and reversibly human platelet aggregation. In conscious dogs, Carafiban showed a high plasma availability of the active moiety of 42±8% and a plasma half-life of 9.9 h after oral administration as measured by bioassay. Carafiban may potentially be used for chronic treatment and prophylaxis of thrombotic diseases in humans.

Ethyl cartrizoate has been used in diagnostics as a bronchographic agent.

Ethyl dibunate is a non-narcotic antitussive agent.

SN38 (7-ethyl-10-hydroxy camptothecin) is a prominent and efficacious anticancer agent. It is poorly soluble in both water and pharmaceutically approved solvents; therefore, the direct formulation of SN38 in solution form is limited. SN38 is formed via hydrolysis of irinotecan by carboxylesterases and metabolized via glucuronidation by UGT1A1. Currently, the water soluble prodrug of SN38, irinotecan (CPT-11), is formulated as a low pH solution and is approved for chemotherapy. SN38 causes the strongest inhibition of DNA topoisomerase I, followed by CPT and then CPT-11. CPT-11 dose dependently shifts the position of relaxed DNA in the direction of nicked DNA, but SN38 and CPT shows no effect on the position of relaxed DNA. SN38 dose-dependently and time-dependently inhibit DNA synthesis. Respective IC50 values of SN38, in DNA synthesis is 0.077 uM.