Derek Lowe

They're basically mini proteins.

To quote the chemist Derek Lowe, for a chemist, peptide has a pretty clear definition.

They're any relatively short chain of amino acids, and when they get longer, we go ahead and call them proteins.

However, exactly where that dividing line is a matter of personal preference.

For example, the pain-relieving peptide zirconatide must be given by infusion into the spinal cord, and so it's approved for certain types of chronic intractable pain.

So unlike paracetamol or ibuprofen, which are small molecules that can be taken orally.

Now, they've been spending a lot of time trying to develop oral formulations for insulin, and they've done some very clever chemistry around nanoparticle delivery systems, which unfortunately none of which have been successful in being approved yet, but that's something we look

forward to in the future.