Cyclopregnol (neurosterone) is a synthetic pregnane steroid, developed in the 1950s by the British Drug Houses, Ltd, for the treatment of psychiatric disorders, such as anxiety, depression and obsessive behavior. In a clinical study, cyclopregnol was not superior to placebo and was inferior to chlorpromazine.

Pregnanediol is a chief steroid metabolite of progesterone that is biologically inactive and occurs as pregnanediol glucuronate in the urine. Pregnanediol has two hydroxyl groups, at 3-alpha and 20-alpha. A test can be done to measure the amount of pregnanediol in urine. The urine test offers an indirect way to measure progesterone levels in the body. It is a standard in the colorimetric determination of urinary pregnanediol in clinical laboratories.

Aglepristone (RU 46534) is a competitive progesterone antagonist; it binds to progesterone receptors (PRs) without inducing the molecular cascade associated with progesterone. Its affinity to PRs is higher than progesterone (3.12, 3.8, and 9.26 times greater in the bitch, doe rabbit,and queen, respectively). Aglepristone can therefore beused in various progesterone-dependent physiological orpathologic conditions, with the aim of blocking the action of progesterone. Aglepristone has proven to be an effective and safe means of inducing pregnancy termination or parturition in a large number of domestic species. In domestic species, aglepristone is routinely used for the treatment of pyometra and feline mammary fibroadenomatous hyperplasia, both of which are progesterone dependent. Aglepristone is marketed under the brand name Alizin used as the treatment option for unwanted mating and pregnancy in dogs

Menarini was developing oral nepadutant (MEN 11420), a potent and selective tachykinin neurokinin-2 receptor antagonist, for the treatment of infant colic. Nepadutant has been used in trials studying the treatment of colic, infantile colic, and infantile functional gastrointestinal disorders. MEN 11420 is a glycosylated derivative of the potent, selective, conformationally-constrained tachykinin NK2 receptor antagonist MEN 10627. MEN 11420 competitively bound with high affinity to the human NK2 receptor stably transfected in CHO cells, displacing radiolabelled [125I]-neurokinin A and [3H]-SR 48968 with Ki values of 2.5+/-0.7 nM (n = 6) and 2.6+/-0.4 nM (n = 3), respectively.

Benorterone (or SKF 7690), a steroidal antiandrogen that was studied in the treatment of acne, seborrhea, and hirsutism in women but was never marketed.

THIOINOSINE (Methylmercaptopurine riboside, NSC- 40774) is a purine derivative with antineoplastic and anti-angiogenic properties. THIOINOSINE is readily converted in cells to its active form, 6-methylmercaptopurine ribonucleoside 5'- monophosphate (MMPR-P), by the enzyme adenosine kinase. THIOINOSINE inhibits amidophosphoribosyltransferase, the first committed step in de novo purine synthesis, and inhibits fibroblast growth factor-2 (FGF2)-induced cell proliferation. It has been used similarly to Mercaptopurine in the treatment of Leukemia. It has being tested in clinical trials for advanced pancreatic cancer.

Apadenoson (BMS-068645) is a selective adenosine 2A agonist that contains a methyl ester group which undergoes esterase hydrolysis to its acid metabolite. Apadenoson had been in phase III clinical trials by Forest (now a part of Allergan) for the treatment of coronary artery disease. However, this study has been terminated.

Lexacalcitol (KH1060) is over 100 times more active than 1alpha,25-dihydroxyvitamin D3 and is of potential interest in the treatment of psoriasis and other diseases characterized by accelerated cell growth and T lymphocyte activation, which was studied in the clinical trial. KH1060 also prevents type I diabetes in the preclinical investigation without significant effects on calcium or bone metabolism. In addition also was shown that neuroblastoma (NB) cell lines were more susceptible to growth inhibition by KH1060, suggesting its possible use in NB to potentiate the action of retinoids, which are in clinical use for this disease. The underlying biochemical reasons for the increased biological activity of KH1060 are unknown, but it can include 1) metabolic considerations in addition to explanations based upon 2) enhanced stability of KH1060-liganded transcriptional complexes.

Afeletecan (Bay 38-3441) is a camptothecin glycoconjugate which stabilizes the active lactone form of camptothecin and allows selective uptake into tumor cells. Afeletecan is a topoisomerase inhibitor. Afeletecan was in phase I clinical trials with Bayer for the treatment of cancer; however, development appears to have been discontinued.

Ciladopa, is a troponylpiperazine derivative and dopamine agonist that has been shown to influence dopaminergic mechanisms in animals. Preclinical pharmacological studies have suggested that it has antiparkinsonian activity similar to that of bromocriptine but without many of the troublesome side effects. Unfortunately in some clinical trials no significant differences was found among the treatment groups and placebo.