Prolarix™ for selected tumours including primary liver cancer
Product information: Primary liver cancer (hepatocellular carcinomas, HCC) is the sixth most common cause of cancer in the world* and is commonly linked to chronic hepatitis B & C infection, alcoholism and exposure to aflatoxins, toxins that are produced by many species of Aspergillus fungus. Chemotherapy and radiotherapy are relatively ineffective in this cancer and surgery or transplantation is only possible in a small number of cases. Despite the recent approval of sorafenib (Nexavar®, Onyx/Bayer), life expectancy for HCC patients remains poor with less than 20% surviving beyond 1 year, and less than 5% surviving beyond 5 years. Despite the considerable unmet clinical need, there are currently few new therapies under development for the treatment of HCC.
Prolarix is a scientifically acclaimed, targeted chemotherapy being developed for the treatment of HCC and other selected tumours. Prolarix is a combination therapy involving the co-administration of a prodrug called tretazicar and an enzyme cosubstrate called caricotamide. In the presence of caricotamide, tretazicar is activated by an enzyme found in the body called NQQ2, to a highly potent cytotoxic agent which has a very short half life. The NQO2 enzyme activity has been found to be elevated in certain tumour types, most notably primary liver cancer, and is found to have much lower activity levels in non-target tissues such as the bone marrow and epithelial cells. As a result of the elevated levels of the enzyme in the target tumour and the short half life of the activated tretazicar, a selective effect on the tumour is expected while minimising harm to healthy, non-cancerous cells. Other potential indications for Prolarix may include ovarian and colorectal cancers.
Technology: Coadministration of prodrug tretazicar and cosubstrate caricotamide, by separate intravenous infusion
Mechanisms of action: The novel action of Prolarix exploits the finding that an endogenous enzyme, NAD(P)H quinine oxidoreductase 2 (NQO2), converts tretazicar to a potent cancer killing agent in the presence of caricotamide
Incidence: Sixth most common cancer in the world*
Market opportunity: >US$500 million worldwide**
* Parkin DM et al, Global Cancer Statistics, 2002
**Protherics estimates
We intend to develop Prolarix in the US and EU in the lead indication of HCC, and to sign a licensing partner for Asia. Please contact our
Business Development team for more information on the Prolarix licensing opportunity.
For further information see the
Prolarix fact sheet