[quote]Wise Guy wrote:
Bill Roberts wrote:
I do know that in pharmaceutical science at the time, the focus in general was formulating for maximum delivery into smallest possible skin area even where skin metabolism was no issue; and I never once saw an effort towards allowing much larger area and much less transport per unit area (flux) on account of being less obtrusive after application. Maximizing flux was the Holy Grail and that was just that.
There are often weird things like that. For example, I am pretty sure you will find medicinal chemistry texts and most certainly medicinal chemistry professors and lecturers who will say that the principal thing, or I even once read, the DEFINITION of medicinal chemistry was increasing potency.
(Meaning, effect per milligram.)
Now that’s just flat stupid.
If derivative B requires three times the milligrams for same effect, but has less side effects at therapeutically-equivalent doses, a more suitable half-life, and is cheaper to manufacturer, then it’s better regardless that it is less potent.
Yet you could find literally thousands of articles in medicinal chemistry where potency is sought as the Holy Grail.
Sidetrack, but not unrelated.
Excellent points.
I have a feeling Big Pharma was simply looking out for layman, everyday user convenience - I.E. the more potent, less amount of gel/cream applied, therefor will have a higher user acceptability ratio, therefore more sales.
I don’t think they were necessarily concerned about things pharmacological speaking, just looking to get a higher user rate. [/quote]
There’s also the consideration that coming up with the Androsol method required information which came from outside of pharmaceutical science.
Simply having a solid on the skin at any ordinarily-conceived amount per unit area would give terribly poor results. It isn’t at all obvious that yet thinner application would be better. Summing the results of each area would seem to give no better outcome.
It was research in environmental toxicology that showed differently. Dr Annette Bunge of the Colorado School of Mines found that absorption of toxins from contaminated soil, due to exposure of skin to that soil, was at a rate well beyond what would ordinarily be predicted.
Her research showed that this was due to rate of lateral (across the top of the skin, rather than through) diffusion being far greater than the rate of transdermal diffusion. So much so, that a microscopic fleck on the skin, where flecks covered only a fraction of any given area, delivered compound through the skin as if it covered much more area than was in fact the case.
Fortunately I met Dr Bunge, due to her being a close colleague of my professor, and learned this.