[mtwalsh01]

Recently on this forum, we have been following the intense on-going research efforts among pharmaceutical companies to address the problem of interferon-based treatments for hepatitis C patients. Problems encountered with interferon-containing medications include contraindications such as psychiatric problems and also a high burden of adverse events. Johnson and Johnson’s drug simeprevir, a second-generation protease inhibitor, is one example of a drug developed to address this issue. Recently winning FDA approval to be marketed under the name of Olysio (http://www.biotechnologyforums.com/thread-2661.html), it reduces the amounts of PEGylated interferon and ribavirin that have to be co-administered. Another drug, Enanta’s lead protease inhibitor ABT-450, has recently delivered promising Phase III data in difficult-to-treat Hepatitis C patients in a pegylated interferon-free regimen (http://www.biotechnologyforums.com/thread-2637.html).

Now entering into the arena is a different type of drug, the pyrimidine nucleotide analog inhibitor of the hepatitis C virus NS5B polymerase, sofosbuvir. This drug, developed by the company Gilead, recently won the backing of FDA agency experts and is expected to be approved by the FDA on December 8th. The drug has shown high efficacy and good tolerability in various treatment combinations in clinical trials and offers the potential to either reduce or remove interferon from the treatment regime. However, it may not all be uncomplicated in bringing this drug to the market as Gilead are facing a legal challenge alleging patent infringements from Idenix Pharmaceuticals, as well as being embroiled in legal issues with Merck, who also claim patent infringements and Roche, who are claiming the licence on sofosbuvir based on a partnership Roche had with Pharmasset, the company which was bought outright by Gilead in order to gain the rights to sofosbuvir. With projected annual sales of approximately $5 billion a year, Gilead will be vigorously defending its exclusive rights to sofosbuvir. As we have previously surmised, the growing ranks of Hepatitis C drugs which reduce or dispense with the need for interferon can only be of benefit for patients, whatever the internal wrangling between pharmaceutical companies.

Sources

http://www.fiercebiotech.com/story/ideni...2013-12-02 [Accessed 3 December]

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RODRIGUEZ-TORRES, M., LAWITZ, E., KOWDLEY, K.V., NELSON, D.R., DEJESUS, E., MCHUTCHISON, J.G., CORNPROPST, M.T., MADER, M., ALBANIS, E., JIANG, D., HEBNER, C.M., SYMONDS, W.T., BERREY, M.M. and LALEZARI, J., 2013. Sofosbuvir (GS-7977) plus peginterferon/ribavirin in treatment-naïve patients with HCV genotype 1: a randomized, 28-day, dose-ranging trial. Journal of Hepatology, 58(4), pp. 663-668.