No, I would say that one has not been proven to be superior over the other. Neither company has an interest in doing a study proving such a thing either: too much money at risk.
Copegus is ribavirin. It's also know as rebetol, and a few other choice names that I could mention but they would show up as asterisks in this post. When it comes to the pegylated inteferons there is Alpha 2a (Roche)- which is Pegasys and there is Alpha 2b, which is PegIntron (Schering). Whether it Pegasys, plus ribavirin or PegIntron plus ribavirin - that's basically the standard of care right now. The main differences would be in doses and duration of treatment.
First, the ribavirin and copegus are identical drugs - just different names. So there is no distinction to be made in that regard.
As to Pegasys vs Peg-Intron I have read different reports as to the comparative efficacy and I suspect that the results of the studies have a lot to do with which drug company is sponsoring the study. When Roche is involved Pegasys generally shows an advantage but when Shering-Plough is involved Peg-Intron usually edges out Pegasys. And there are often differences that make a true head to head comparison impossible. I got so tired just trying to sort it out that I stopped reading any studies where one of the major drug companies was a sponsor. My opinion is that they're pretty much the same in terms of effectiveness but perhaps one does better with a particular genotype. I really can't say with any degree of certainty. I took both and cleared with both but I stopped too soon with Peg-Intron and relapsed. Then I took a Pegasys for a longer time and increased my ribavirin dose and cleared and stayed clear. I will say that I had a much easier time tolerating the Pegasys - the side effects were much easier on me. When you look at the studies which purport to compared the two drugs look closely to see whether ribavirin/copegus doses were the same in each. Sometimes one study group will use fixed dosing and the other will use weight based dosing and that can make a big difference. People will say that Pegasys is a larger molecule and its distribution is not as widespread and that it doesn't need to be weight dosed. Others will say that if you are heavy Peg-Intron is a better choice because it is weight based. I used to think I knew something about this stuff but nowadays I don't think I know much except that the Pegasys was a lot easier for ME to handle and I have heard others say the same thing. Mike
Pressed 'enter' too soon. I haven't read anything that convinces me that one Peg is more effective than another. I've used both. Relapsed after Intron and 800 riba for 24 weeks. Am currently using Pegasys and 1200 mg riba, going 46 weeks. Even if I get to svr this time I won't be convinced it was the Peg, since the doses (mainly riba) and the duration (much longer) will make the results not comparable. But, I do find that Pegasys is more tolerable than the PegIntron. Some people find the same, but not all. I just knew that I needed to do something very different in order to expect different results from the first time. You might find that some docs are 'oriented' to one peg over the other, for whatever reason and there are several.
According to Dr. J they are the same meds made by different companies and there isn't really that much discernable difference. IE: Advil name brand versus Motrin name brand. Same med.
Of course some bodies can tolerate one better than the other but that is physiologican per person.
I've taken Rebetol, Ribavirin and Copegus during the course of treatment. From capsules to tablets. All the same in so much as they ARE interchangeable.
Same with the PegIntron vs. Pegasys