Written by William Llewellyn
17 October 2017

16NN306-oral

Drugs In Sport Breakthrough - Oral GH May Be Coming!

 

 

Human growth hormone (somatropin) is among the more common non-steroid drugs used in bodybuilding and sport. It is a powerful growth mediator, essentially identical to the growth hormone circulating in our bodies at especially high levels when we are young. Pharmaceutical human growth hormone (hGH) is expensive, though, and not the most comfortable drug to use on top of it. It traditionally requires daily subcutaneous injections. Though some progress has been made with reducing injection frequency, we haven’t seen any major breakthroughs with novel delivery methods as of yet. That may soon change, however. According to a recent study in the Journal of Biomaterials Applications, researchers have succeeded in creating the first orally viable form of hGH.1 Oral hGH would, of course, be a game-changing technology.

 

For a long time, many scientists were skeptical that such a route of administration would ever be possible. The reason is simple. Human growth hormone is a complex and fragile peptide (protein) made of 191 amino acids. These amino acids are present in a very particular sequence and arrangement (fold). The digestive process can be harsh, and very destructive to fragile proteins like this. Normally, you cannot expect to receive an appreciable amount of hGH in the blood by giving it to someone orally. The body will destroy it first. Overcoming this barrier is an exceedingly difficult challenge. If this research holds true, it would represent the single greatest achievement in this field since the development of recombinant technology, which is used to reproduce the hGH protein.

 

How It Works

The method the researchers used to produce an orally effective hGH, in this case, is twofold. First, they applied enteric coating on their hGH capsules. This is a fairly common technology these days, where the capsule will not open in the high-acid environment of the stomach. They only break open after they pass through to the small intestines (the ileum, specifically), where there is a significant increase in pH (reduced acidity). This alone would likely not yield an effective product, however. They also tried that for comparison, in fact. The digesting process continues to be destructive. In this case, the researchers also placed the fragile proteins into tiny nanoparticles. These nanoparticles were made of monomethoxyl poly(ethylene glycol)-b-poly(L-lactide-co-glycolide), also know as PEG-PLA. This is a nontoxic polymer increasingly used to aid drug delivery. These particles serve to further protect the protein from degradation, carrying it into circulation and onward to tissues.

  roidtest650

How Well It Works

These experiments were conducted on animals, so we don’t have human data to draw from. Still, the results were quite encouraging. Subcutaneous hGH was administered to some animals to produce a baseline of comparison. When given by injection, of course, the entire digestive process is bypassed, and bioavailability nears 100 percent. The animals given the oral growth hormone capsules noticed about 11 percent bioavailability in comparison. While not necessarily close, these numbers are remarkable, given the challenge at hand. If they hold true in humans, the raw numbers at least suggest the concept could work. Further, the distribution pattern of the oral hGH might even be considered improved. Though the peak was lower, hormone levels remained elevated for a longer time. In this case, the subcutaneous injection lasted roughly five hours, with most of the hormone lost by hour four. The oral medication produced a slower rising and lowering pattern in serum hGH, but the total distribution lasted for nearly 12 hours.  

 

What’s Next?

These experiments are very exciting. But we mustn’t get too far ahead of ourselves. They first need to be replicated in human subjects, of course. The approval to even test this in humans would require several more stages of investigation, and significant financial support (I am not sure if that is there right now). Further, the high cost of somatropin may still preclude the use of this technology in pharmaceuticals. It could still require as much as nine times more hormone for an equivalent (total) delivery to the patient. That is, if the 11 percent bioavailability numbers even hold up. While hGH processing costs have plummeted in recent years, we’re not quite at a place where nine times greater raw materials costs don’t seem daunting. Still, we’re on the right track. For certain, this is a subject I’m going to keep an eye on. I am starting to believe we could see an oral hGH in the not too distant future.

 

Reference:

1. Yanan Shi, Keke Li, et al. Oral delivery of human growth hormone: Preparation, characterization, and pharmacokinetics. J Biomater Appl 2016;Oct 14.

          

William Llewellyn is the author of the anabolic steroid reference guide, ANABOLICS 10th Edition. He is also a longtime team member at Muscular Development, having been a regular monthly columnist since 2002. William adapted this steroid profile from his work at anabolic.org. He is also credited with helping to develop ROIDTEST™, an at-home steroid testing kit used to identify real and fake steroid products.

 

DISCUSS THIS ARTICLE ON THE MD FORUM

READ MORE ARTICLES LIKE THIS IN THE CHEM SECTION

 

FOLLOW MUSCULAR DEVELOPMENT ON:

FACEBOOK: MuscularDevelopment Magazine

TWITTER: @MuscularDevelop

INSTAGRAM: @MuscularDevelopment

YOUTUBE: http://bit.ly/2fvHgnZ