Marizomib is a natural beta-lactone produced by the marine bacterium Salinispora tropica. Marizomib has a broad inhibition profile for the 20S proteasome and has been shown to inhibit the CT-L (beta5) CT-T-laspase-like (C-L, beta1) and trypsin-like (T-L, beta2) activities of the 20S proteasome. The drug is being tested in phase II clinical trials for the treatment of Multiple Myeloma and Malignant Glioma and in phase I in patients with Non-small Cell Lung Cancer, Pancreatic Cancer, Melanoma or Lymphoma

The monoterpene perillyl alcohol (POH) is a naturally occurring compound derived from citrus fruits, mint, and herbs. It exhibited chemotherapeutic potential against various malignant tumors in preclinical models and was being tested in clinical trials in patients with refractory advanced cancers. POH was formulated in soft gelatine capsules and orally administered to cancer patients several times a day on a continuous basis. However, such clinical trials in humans yielded disappointing results, also because of the large number of capsules that had to be swallowed caused hard-to-tolerate intestinal side effects, causing many patients to withdraw from treatment due to unrelenting nausea, fatigue, and vomiting. The clinical trials in Brazil have explored intranasal POH delivery as an alternative to circumvent the toxic limitations of oral administration. In these trials, patients with recurrent malignant gliomas were given comparatively small doses of POH via simple inhalation through the nose. Results from these studies showed, that this type of long-term, daily chemotherapy was well tolerated and effective. The precise mechanism of action is still undetermined, but it is known, that perillyl alcohol plays an important role in the process of hepatoma cell invasion and migration via decreasing the activity of Notch signaling pathway and increasing E-cadherin expression regulated by Snail. Another possible mechanism is included inhibition of Na/K-ATPase (NKA). The NKA α1 subunit is known to be superexpresses in glioblastoma cells (GBM) and POH acts in signaling cascades associated with NKA can control cell proliferation and/or cellular death.

Axamozide is a neuroleptic agent.

Azabyperone was developed as tranquilizer and neuroleptic and has never been marketed.

Rabusertib is a Chk1 kinase inhibitor which was developed by ICOS for the treatment of cancer. The drug was tested in phase II of clinical trials for pancreatic cancer and non small cell lung carcinoma, but its development was discontinued. Now the drug is undergoing phase I trial in Japanese patients with solid tumors.

Intiquinatine is a quinolone derivative patented by Wayne State University as antineoplastic agent. Intiquinatine exhibited efficacy against early stage mammary cancer (Mam-17/Adr) and showed none of the neuromuscular toxicity.

XL-228 is a third generation inhibitor of Abl that shows efficacy in a variety of cell lines, including those exhibiting T315I mutations. XL-228, a tyrosine kinase inhibitor, is involved in binding to and inhibiting the activities of multiple tyrosine kinases, such as the insulin-like growth factor 1 receptor (IGF1R), Src tyrosine kinase, and Bcr-Abl tyrosine kinase. Blockade of these kinases may result in the inhibition of tumor angiogenesis, cell proliferation, and metastasis. XL-228 is a multitargeted protein kinase inhibitor targeting IGF1R, the aurora kinases, IGF-1R, cSrc, BCR/Abl and SRC kinases. XL-228 displays anticancer chemotherapeutic activity and it was in clinical trials as a potential treatment for chronic myelogenous leukemia (CML). On 22 Feb 2011 phase I clinical studies for chronic myeloid leukaemia and cancer in USA were discontinued.

Icoduline (previously known as CBS-113 A) is a dual inhibitor of 5-lipoxygenase and cyclo-oxygenase with anti-inflammatory properties. This drug was potentially useful in ophthalmology and as an alternative to glucocorticoids. In addition, icoduline was useful to treat skin disorders. The drug participated in the clinical trial for eye disorders in France; however, this study was discontinued.

Icospiramide was developed as an antiemetic agent that has never been marketed.

Anhydrovinblastine (AVLB) is a semisynthetic vinca alkaloid, which can safely be administered every 3 weeks at a dose of 21 mg/m2. Anhydrovinblastine is a cell cycle-specific anti-mitotic agent whose anti-tumour activity is directly related to its ability to bind tightly to tubulin and inhibit its polymerization into microtubules. Anhydrovinblastine has been used in trials studying the treatment of adult solid rumor, but this research has been discontinued.