Biotech Values

[iwfal]

The decrease in plaque volume in the torcetrapib–atorvastatin group was small but represented a reduction of 50% more than that in the atorvastatin-only group. The fact that the change in plaque volume was larger than the change in percent atheroma volume (the percentage of total vessel volume occupied by plaque) could suggest that a decrease in atheroma volume was offset by an overall shrinkage of the vessel

This shrinkage of the vessel as Atheroma volume decreases should be EXPECTED for soft plaque. It is called "arterial remodelling" and is very very typical. Lots of trials showing it and its inverse in IVUS.

I'd love to see revasc numbers from the Torc trials. I'd give it 70% chance that the revasc is neutral (p>0.7) or weighted in favor of Torc (i.e. Torc prevents revasc) - especially in the US where there is a lot of revasc for Stable Angina. Keeping the plaque soft allows remodeling to continue so there will be fewer Stable Angina patients, but more MI/death.

Note that the fact that they were using %atheroma volume as the primary endpoint is an indication of poor trial design IMO. Remodeling is well known, albeit a little arcane.

Clark