Oxaliplatin is used for treatment of colorectal cancer, typically along with folinic acid and 5-fluorouracil in a combination known as FOLFOX. Oxaliplatin has been compared with other platinum compounds used for advanced cancers, such as cisplatin and carboplatin.
Advanced colorectal cancer
Oxaliplatin by itself has modest activity against advanced colorectal cancer. When compared with just 5-fluorouracil and folinic acid administered according to the de Gramont regimen, a FOLFOX4 regime produced no significant increase in overall survival, but did produce an improvement in progression-free survival, the primary end-point of the phase III randomized trial.
After and/or before the curative resection of colorectal cancer, chemotherapy based on 5-fluorouracil and folinic acid reduces the risk of relapse. The benefit is clinically relevant when cancer has spread to locoregional lymph nodes or penetrated through the wall of the rectum or colon. The addition of oxaliplatin improves relapse-free survival, but data on overall survival have not yet been published in extenso.
Adverse effects
Side-effects of oxaliplatin treatment can potentially include:
Neurotoxicity leading to chemotherapy-induced peripheral neuropathy, a progressive, enduring and often irreversible tingling numbness, intense pain and hypersensitivity to cold, beginning in the hands and feet and sometimes involving the arms and legs, often with deficits in proprioception. This chronic neuropathy may also be preceded by a transient acute neuropathy occurring at the time of infusion and associated with excitation of voltage-gated Na+ channels.
In addition, some patients may experience an allergic reaction to platinum-containing drugs. This is more common in women. Oxaliplatin has less ototoxicity and nephrotoxicity than cisplatin and carboplatin.
Structure and mechanism
The compound features a square planar platinum center. In contrast to cisplatin and carboplatin, oxaliplatin features the bidentate ligand1,2-diaminocyclohexane in place of the two monodentate ammine ligands. It also features a bidentateoxalate group. The three-dimensional structure of the molecule has been elucidated by X-ray crystallography, although the presence of pseudosymmetry in the crystal structure has caused confusion in its interpretation. According to in vivo studies, oxaliplatin fights carcinoma of the colon through non-targeted cytotoxic effects. Like other platinum compounds, its cytotoxicity is thought to result from inhibition of DNA synthesis in cells. In particular, oxaliplatin forms both inter- and intra-strand cross links in DNA, which prevent DNA replication and transcription, causing cell death.
History
Oxaliplatin was discovered in 1976 at Nagoya City University by Professor Yoshinori Kidani, who was granted U.S. Patent 4,169,846 in 1979. Oxaliplatin was subsequently in-licensed by Debiopharm and developed as an advanced colorectal cancer treatment. Debiopharm licensed the drug to Sanofi-Aventis in 1994. It gained European approval in 1996 and approval by the U.S. Food and Drug Administration in 2002. Generic oxaliplatin was first approved in the United States in August 2009. Patent disputes caused generic production to stop in 2010, but it restarted in 2012.
Patent information
Eloxatin is covered by patent numbers 5338874, 5420319, 5716988 and 5290961 . Exclusivity code I-441, which expired on Nov 04, 2007, is for use combination with infusional 5-FU/LV for adjuvant treatment stage III colon cancer patients who have undergone complete resection primary tumor-based on improvement in disease free survival with no demonstrated benefit overall survival after 4 years. Exclusivity code NCE, New Chemical Entity, expired on Aug 09, 2007.
