Oral Insulin – Microneedle patch drug delivery in the gut
A novel oral capsule can deploy microneedle patches that release drugs into the intestinal wall for uptake into the bloodstream as shown in animal studies, thereby avoiding injections.
Patients dislike shots and often cannot self-administer them. Therefore, doctors are frequently hesitant to prescribe injectable medication if there is an alternative drug in pill form, even if it is less effective. It has therefore been a goal of drug-delivery research for decades to deliver drugs currently requiring injection, such as biologics, orally instead.
In this issue, Abramson and colleagues present a novel pill that ejects microneedle patches within the intestine, which then deliver drugs across the intestinal epithelium and into the bloodstream without the need for hypodermic injection4. Oral delivery is limited to drugs that can survive the acidic environment in the stomach, mucus and epithelial barriers in the intestine and enzymatic degradation in the intestine and liver.
According to Lipinski’s famous Rule of Five, oral drugs generally have molecular weight <500 Da and are lipophilic, without too many hydrogen bond donors or acceptors6. These constraints rule out oral delivery of proteins, genetic material or other macromolecules so that almost all biologics are administered by injection. Read more about oral insulin delivery
Mark R. Prausnitz, Yasmine Gomaa & Wei Li
Nature Medicine volume 25, pages1471–1472 (2019)