Tim,
Thanks for your posts sifting through the Viracept abstracts. There are very good data for Viracept presented here, as per the points you raise. There is also an interesting abstract about compliance with PI's among inner city patients. It's a little unclear, but it could be read to indicate that nelfinavir patients were more likely to stay on drug than patients using other PI's.
Two other points jump out at me from my first cursory scan of the abstracts.
1 - There doesn't seem to be enough data in the abstracts alone to establish an opinion of Vertex / Glaxo's Amprenavir. It appears to be a quality contender. There's one study (abstract 512) that may be the study that is giving rise to the rumors of very high levels of anti-viral potency ... but there aren't enough data to evaluate based on the abstract ... maybe there will be 16-week data on % undetectable presented this next week.
2 - Saquinavir-SGC (Roche's Fortovase) looks like a real player. From the abstracts, it looks like it has excellent anti-viral potency (on a par with indinavir (Crixivan) and nelfinavir), and is well tolerated. FWIW, it's a higher dose (1200mg TID) than nelfinavir (750mg TID) ... In addition, it's clear that saquinavir-sgc and nelfinavir are more potent together than either one alone.
What does this mean? Well, on the plus side, nelfinavir and saquinavir-sgc are a highly potent, well-tolerated dual PI combination. As AGPH has pointed out, the lions share of current dual PI use is saquinavir (hard gel formulation) + ritonavir, but as new data like the saq-sgc / nelf study come out, that should change.
However, Roche are not in this to make AGPH or anyone but Roche rich ... and saquinavir-sgc looks like it's a very strong contender as a single PI in combination therapy. Hence, a lot less incentive to push Viracept over their own product than they had when signed the original deal ... saquinavir-hgc of course being an inferior product due to poor bioavailability. As has been pointed out on this thread, AGPH's deal with Roche provides them some benefit if Roche sells their product instead Viracept (there's a royalty rate on Roche's sales of Viracept, a lower royalty rate on Roche's sales of saquinavir, and AGPH gets the greater of the two) ... but still I wonder what implication Roche having data showing their own product equivalent to Viracept in single-PI therapy will have on Roche sales of Viracept, and consequently, AGPH revenue from Roche.
BTW, there's a ton of stuff here at the conference website. Well worth the time spent ...
Peter |
