Single polymer pill to deliver entire drug course
Emily Hughes looks at how scientists in the US have designed a single pill made from a polymer gel that could deliver an entire treatment in a single dose
The breakthrough pill could help end problems of patients failing to finish a course of medication, which can exacerbate illnesses and has contributed to the rise of antibiotic resistance bacteria.
Robert Langer from the Massachusetts Institute of Technology (MIT), said: “Probably one of the biggest health problems in the world… [is] patient compliance – people forgetting to take their drugs.
“As a consequence, there are many deaths, enormous amounts of hospitalisations, hundreds of billions of dollars in healthcare costs.”
Langer and his colleagues’ pill had to tackle two key issues.
The device had to be able to survive the harsh environment of the stomach and slowly release its drug payload, but dissolve once it eventually passed through into the intestine.
It also needed to be flexible enough to swallow and then unfold in the stomach to prevent its expulsion into the intestines.
The team designed a supramolecular elastomer gel by combining poly(acryloyl 6-aminocaproic acid) and poly(methacrylic acid co-ethyl acrylate), a pharmaceutical-grade polymer that resists digestion.
The gel can be cut to various sizes and recovers its shape quickly after being stretched to three times its original length.
As a proof-of-concept, Langer and his colleagues embedded polycaprolactone (PCL) beads, as an example of slow drug release agent, into a ring of the elastomer gel and inserted the device into a standard 18mm gelatin capsule.
When the capsule gets into the stomach the outer part dissolves and the elastomer opens up into a particular shape.
The pill was successfully tested on a pig and in this case, the gel opened up into a 3.2cm ring within the pig’s stomach.
The ring remains intact for up to seven days, before the gel component dissolves and the PCL beads can safely travel through the animal’s intestine.
Gregor Fuhrmann from Imperial College London, UK, said: “I very much like the simple idea of creating an elastic polymer that is gastro-resistant but dissolves at intestinal pH.
“The development of this elastic polymer may open the door for future developments in drug delivery.”
Langer said: “It has the potential to change the way we take drugs. It’ll, I hope, save many, many lives.”