Advanced Telaprevir Trial Cures 75 Percent of HCV
One of the most promising drugs in development continues to prove itself as the leading contender for improving Hepatitis C antiviral treatment. Currently in Phase III clinical trials, Vertex’s telaprevir is in the last stage before obtaining FDA approval. The likelihood of telaprevir becoming widely available soon has just grown since Vertex’s recent announcement that telaprevir plus the current standard of treatment substantially increases Hepatitis C treatment’s success rate.
Consisting of pegylated interferon and ribavirin, the currently approved Hepatitis C antiviral treatment is only about 50 percent effective for those with the most common genotype in America – Hepatitis C genotype 1. With an estimated four to five million Americans at risk of advanced liver disease because of chronic infection with the Hepatitis C virus, a 50 percent success rate is far too low. Also referred to as combination therapy, experts have been predicting for a while that pegylated interferon and ribavirin need a third medication to increase the chance for curing Hepatitis C.
Telaprevir’s readiness for the Hepatitis C market is currently being evaluated by three Phase III trials, one of which is known as the ADVANCE study. The specifics of the three studies differ slightly from one another. The three Phase III trials designed to test telaprevir, include:
- ADVANCE – In October 2008, Vertex completed enrollment in ADVANCE, the first Phase III clinical trial of telaprevir. ADVANCE is evaluating 24-week telaprevir-based treatment regimens in those with Hepatitis C genotype 1 who have never attempted treatment before. These individuals are known as treatment naïve.
- ILLUMINATE – In January 2009, Vertex completed enrollment in ILLUMINATE. This trial is evaluating 24-week and 48-week telaprevir-based regimens in those with Hepatitis C genotype 1 who are treatment naïve.
- REALIZE – In February 2009, Vertex and its collaborator, Tibotec, completed enrollment in REALIZE. This trial is evaluating telaprevir-based treatment regimens for those with Hepatitis C genotype 1 who were previously unsuccessful with pegylated-interferon and ribavirin. These individuals are also known as previous non-responders.
For the purpose of defining what successful Hepatitis C treatment entails, investigators and clinicians use a sustained viral response (SVR) as their determination of success. SVR is considered to be attained if zero Hepatitis C genetic material is detectable immediately following the end of treatment and 24 weeks after the end of treatment.
During the last week of May 2010, Vertex announced results from ADVANCE. The announcement included:
- After 12 weeks of dosing with telaprevir, pegylated interferon and ribavirin was followed by another 12 weeks of just pegylated interferon and ribavirin, 75 percent of treatment naïve patients with Hepatitis C genotype 1 achieved SVR.
- After just 8 weeks of dosing with telaprevir, pegylated interferon and ribavirin was followed by another 16 weeks of just pegylated interferon and ribavirin, 69 percent of treatment naïve patients with Hepatitis C genotype 1 achieved SVR.
- After 48 weeks of treatment with the currently approved regimen of pegylated-interferon and ribavirin, 44 percent of treatment naïve patients with Hepatitis C genotype 1 achieved SVR. As this is the currently recommended medication combination and time frame used to treat Hepatitis C, this was the control group.
Since the addition of telaprevir to the current standard Hepatitis C treatment yields far better results in about half the time, many currently infected people are eagerly anticipating this treatment being available to the public. According to Ira Jacobson, MD, Chief of the Division of Gastroenterology and Hepatology, Weill Cornell Medical College and an Investigator for the ADVANCE trial, “The ADVANCE results confirm findings seen in earlier trials of telaprevir and highlight that telaprevir-based combination regimens may increase viral eradication rates and shorten treatment time for many patients.”
With such good news coming from the ADVANCE trial, Vertex has indicated that it expects to request FDA approval for telaprevir in the second half of 2010. That means that the long wait for an improved Hepatitis C treatment could finally be right around the corner.
References:
http://www.vrtx.com/
current-projects/drug-candidates/telaprevir-VX-950.html, Telaprevir (TX-950), Retrieved June 19, 2010, Vertex Pharmaceuticals, 2010.
http://www.bioworld.com/servlet/com.accumedia.web.Dispatcher?next=bioWorldHeadlines_article&forceid=54657, First Phase III Data on Vertex’s Telaprevir: 75% HCV Viral Cure, Trista Morrison, Retrieved June 18, 2010, BioWorld, 2010.
http://www.hivandhepatitis.com/hep_c/news/2010/0608_2010_a.html, 75% of Treatment-naive Genotype 1 Hepatitis C Patients Achieve Sustained Response with Telaprevir Combination, Most with 24 Weeks of Therapy, Retrieved June 18, 2010, hivandhepatitis.com, June 2010.
http://www.webmd.com/hepatitis/news/20100526/hepatitis-c-drug-telaprevir-ups-cure-rate?ecd=wnl_hep_061710, Hepatitis C Drug Telaprevir Raises Cure Rate, Daniel J. DeNoon, Retrieved June 18, 2010, WebMD, LLC, 2010.