When is a drug a risk?

In my last blog I discussed the origins of a class of drugs known as angiotensin receptor blockers.  I have had an opportunity to work with all of these compounds at one time or another.  It started with the very first in class losartan developed by Merck when it was still a “number” and not yet given a chemical name.

One of the most interesting things about these compounds is that they were the first drug with “no side effects.”  What I mean by that: when drugs are tested, the side effect profile is the number of side effects in the drug class minus the side effects in the placebo class.  These were generally equal.  These drugs are very well-tolerated–much more so than their sister compounds, the angiotensin converting enzyme inhibitors.

These drugs were widely tested in many disease states and we participated in many of those trials.  That is how this Meta analysis came to be.  Remember a Meta analysis is a study that combines many different patients across a wide array of studies but uses the same compound.

As reported in The Lancet Oncology, this report found a 25% increase in lung cancer occurrence with this drug class compared with placebo.  There was no increase in prostate or breast cancer. There was no significant increase in cancer deaths in the two groups.  The number of patients need to treat to developed one cancer was 105 patients treated for four years.

This observation has been seen before in the CHARM study which used the compound candesartan.  We contributed to this study.  An excess of cancer deaths was seen but felt to be due to “chance”.  This Meta analysis study combined the date for 61,950 patients from five trials.  87.5% received the compound telmisartan and the rest losartan or candesartan.

Here is the “kicker”.  The 25% number is the RELATIVE RISK.  The actual numbers were 7.2% vs. 6.0%.  Only lung cancer was more prevalent 0.9% vs. 0.7%.

What does this all mean?  What is the perspective here?   Next blog…

Tags: angiotensin receptor blockers

This entry was posted on Tuesday, June 22nd, 2010 at 6:09 pm and is filed under Clinical trials. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.