Last Monday , the US regulator granted marketing approval for Austedo – previously known as SD-809 – based on its ability to reduce the characteristic jerky motions – chorea – associated with Huntington’s.
Austedo’s active pharmaceutical ingredient (API) tetrabenazine has been used to treat movement disorders for decades. However, Teva’s product differs in that six of the molecule’s hydrogen atoms have been replaced with deuterium – known as heavy hydrogen.
Teva spokeswoman Doris Saltkill told us switching an API’s hydrogen atoms for deuterium increases the length of time it circulates in the body.
“Teva has a proprietary deuterium technology that is used in Austedo and is being investigated for other products as well” she said, explaining “a key benefit of deuterated product is to improve the pharmacokinetic profile with the intent of improving tolerability and potentially reducing dosing.”
Deuterated drug wave?
Austedo was developed by a firm called Auspex Pharmaceutical Inc, which Teva acquired in 2015 .
Other generic drug firms have developed deuterated products. However, intellectual property issues and business decisions have slowed progress according to Dr Graham Timmins from the University of New Mexico’s College of Pharmacy.
He told us “In some cases the major pharma player that owns the IP for non-deuterated versions buys the deuterated IP assets from smaller deuterium-switch company,” citing Cellgene’s takeover of Deuteria in 2015 or Vertex’s acquisition of patents from Concert Pharma.
Timmins explained that: “Depending upon the major buyer’s needs and the likely clinical benefit, they may just stop development of the deuterated asset, or slow it down.”
However, Timmins predicted more deuterated drugs will be approved in the wake of Austedo.
He suggested: “Vertex could switch from Kalydeco to a deuterated version close to patent expiry,” adding that clinical data indicate the deuterated version of the cystic fibriosis (CF) drug has an improved pharmacokinetic profile.