DJNews Vertex and Alios BioPharma Begin Clinical Studies of Nucleotide Drug - Link
That's a great question--why not study ALS-2200 and ALS-2158 in GT1, GT2 and GT3 rather than just GT1? My best guess is Vertex expects there will be an oral regimen with a high cure rate already approved for the easier to treat GT2/3 patients long before they would be able to get the Alios "nucs" approved for GT2/3. Therefore, rather than spending perhaps twice as much money on clinical trials to cover all three genotypes, they will focus on just the more difficult to treat GT1 patients which comprise about 75% of HCV cases in north america. The fact that Vertex is focusing on finding an oral regimen (with "nucs") for GT1 patients provides more evidence that expectations are that Pharmasset's oral regimen will fail in GT1 HCV patients. GILD's $11 billion purchase would make sense if VRUS really had a pan-genotypic oral treatment for HCV. The fact is that VRUS has not provided any data to show that their oral regimen has a significant cure rate for GT1 HCV. Given Pharmasset's PR machine, you can bet that if they had positive data in GT1's, they would have released it. And if they believed they had an oral cure for GT1's, they would be doing a phase III study just for GT1's. Instead, they want to create confusion by doing a phase III without regard for genotype and requiring the patients to be "interferon intolerant," whatever that means.
VRUS has data on 7977+Riba+INF. Their data was on an easy to treat group of geno 1 patients. For example it did not have a sinple Afican decent person (hard to treat). Those results showed 93% SVR (possibly less if you count the drop outs I believe).
So common sense tells us that when they took out INF and administered only 7977+Riba their results will be less than 93% SVR. That is why VRUS is hyping Geno 2 &3 instead because they know the results for oral geno 1 will not be great.
Ultimately, the $11 billion GILD purchase of VRUS will not be indicative of a remarkable advance in the treatment of HCV, but rather it will be remembered as a remarkable feat of salesmanship. Not since Billy Mays sold Ginsu knives in infomercials has so much been promised based on so little evidence. Unfortunately, for GILD, there is no money back guarantee as there was for those who found out the Ginsu knife won't cut through everything.