Treosulfan (l-threitol-1,4-bis-methanesulfonate; dihydroxybusulfan) is a prodrug of a bifunctional alkylating cytotoxic agent that is approved for the treatment of ovarian carcinomas in a number of European countries. The antitumor activity of treosulfan has been shown in a variety of solid tumors. It is used for the treatment of all types of ovarian cancer, either supplementary to surgery or palliatively. Treosulfan is a prodrug that is converted nonenzymatically first to a mono-epoxide – (2S,3S)- 1,2-epoxy-3,4-butanediol-4-methanesulfonate – and then to a diepoxide – l-diepoxybutane, which is also a metabolite of butadiene – under physiological conditions. Such conversions are assumed to account for the alkylating and therapeutic activities of treosulfan.

OTL-38 (OTL-0038, Pafolacianine), a fluorescent-labelled folate receptor-α (FRα) targeted imaging agent that accumulates in vivo in tumor cells expressing FR. In 2014, the OTL-38 molecule was granted orphan drug status which can be given to the maker of a drug that treats rare conditions or diseases and offers protection from competition for a period of time. OTL-38 under the brand name Cytalux was approved by the U.S. Food and Drug Administration (FDA) on 29 November 2021, as an additional approach that can be used to identify malignant lesions and to ensure the total resection of the tumors in ovarian cancer patients. Cytalux is a fluorescent drug that targets folate receptor which may be overexpressed in ovarian cancer. Pafolacianine binds to FR-expressing cancer cells with ~1 nM affinity, internalizes via receptor mediated endocytosis, and concentrates in FR-positive cancer tissues. Pafolacianine absorbs light in the near-infrared region within a range of 760 nm to 785 nm with peak absorption of 776 nm and emits fluorescence within a range of 790 nm to 815 nm with a peak emission of 796 nm.

Lurbinectedin (PM-01183) - is a synthetic tetrahydropyrrolo [4, 3, 2-de]quinolin-8(1H)-one alkaloid analogue with potential antineoplastic activity. Lurbinectedin covalently binds to residues lying in the minor groove of DNA, which may result in delayed progression through S phase, cell cycle arrest in the G2/M phase and cell death. Lurbinectedin is a novel anticancer agent currently undergoing late-stage (Phase II /III) clinical evaluation in platinum-resistant ovarian, BRCA1/2-mutated breast and small-cell lung cancer. Lurbinectedin is structurally related to trabectedin and it inhibits active transcription and the DNA repair machinery in tumour cells.

Selinexor (KPT-330) is a first in class XPO1 antagonist being evaluated in multiple later stage clinical trials in patients with relapsed and/or refractory hematological and solid tumor malignancies.

BMN-673 (8R,9S) is the (8R,9S) enantiomer of BMN-673, known as talazoparib. BMN 673 is a novel inhibitor of nuclear enzyme poly (ADP-ribose) polymerase (PARP) with potential antineoplastic activity.

Fostamatinib is a pro-drug of a Syk inhibitor R406 initially developed by Rigel Pharmaceuticals, but then in-licensed by AstraZeneca. It reached phase III of clinical trials for such diseases as Rheumatoid Arthritis and Immune Thrombocytopenic Purpura, however, AstraZeneca decided not to proceed with regulatory filings and return the rights to the compound to Rigel Pharmaceuticals. In 2018 the drug was approved by the FDA for treatment of chronic immune thrombocytopenia. Fostamatinib is being developed for Autoimmune Hemolytic Anemia (phase II), graft versus host disease (phase I) and ovarian cancer (phase I).

Niraparib (MK-4827) displays excellent PARP 1 and 2 inhibition. Inhibition of PARP in the context of defects in other DNA repair mechanisms provide a tumor specific way to kill cancer cells. Niraparib is in development with TESARO, under licence from Merck & Co, for the treatment of cancers (ovarian, fallopian tube and peritoneal cancer, breast cancer, prostate cancer and Ewing's sarcoma). Niraparib was characterized in a number of preclinical models before moving to phase I clinical trials, where it showed excellent human pharmacokinetics suitable for once a day oral dosing, achieved its pharmacodynamic target for PARP inhibition, and had promising activity in cancer patients. It is currently being tested in phase 3 clinical trials as maintenance therapy in ovarian cancer and as a treatment for breast cancer.

Rucaparib is a poly (ADP-ribose) polymerase (PARP) inhibitor indicated for the treatment of advanced mutant BRCA ovarian cancer. Rucaparib is being investigated in clinical trials against prostate cancer, breast cancer and other neoplasms.

Trabectedin (ET-743) is a marine alkaloid isolated from the Caribbean tunicate Ecteinascidia turbinata. Trabectedin was approved for the treatment of liposarcoma or leiomyosarcoma (USA and Europe) and ovarian cancer (only in Europe). Trabectedin exerts its anti-cancer action by binding guanine residues in the minor groove of DNA. The binding prevents DNA from interacting with transcription factors and the reparation system and results in perturbation of the cell cycle and eventual cell death.

Olaparib is an oral inhibitor of poly (ADP-ribose) polymerase enzymes, including PARP1, PARP2, and PARP3 which are involved in normal cellular homeostasis, such as DNA transcription, cell cycle regulation, and DNA repair. Olaparib has shown activity in ovarian and breast tumors with known BRCA mutations and was the first FDA approved drug in this class. Lynparza (olaparib) is indicated for treatment of gBRCA-mutated advanced ovarian cancer. Its use together with other chemotherapy medicines can lead to increased effects on the blood resulting in reduction in the numbers of white blood cells and platelets, and anaemia.