Concert Pharmaceuticals Hits $4 Million Milestone in GSK Alliance
Lexington, MA-based Concert Pharmaceuticals announced today that it has moved three novel drug candidates forward in its pipeline—one of which earned it a $4 million milestone payment from GlaxoSmithKline (NYSE: GSK). The European drug giant allied with Concert on an HIV program in 2009, and the molecule, called CTP-298, is now the lead compound in that program.
Glaxo has pledged up to $1 billion in equity and milestone payments to Concert based on the success of its program, which centers on making longer-acting versions of approved HIV treatments by swapping out certain hydrogen atoms in drugs with deuterium atoms. With this last milestone payment, Concert has reaped a total of $50 million from the deal so far.
Concert’s goal is to use its deuterium platform to modify atazanavir, one of the most widely used HIV treatments, which is in the drug class known as protease inhibitors. Currently, atazanavir is commonly given with a boosting agent called ritonavir, which prevents it from getting destroyed by enzymes in the body before it has a chance to be effective. Eliminating the need for ritonavir would simplify the HIV regimen for patients—a big selling point, says Concert CEO Roger Tung.
“Ritonavir is one more pill to remember,” Tung says. “And it’s not a totally benign agent. It causes some patients to get nauseous and it has cardiovascular risk factors. Our goal is to create a drug that can be dosed once a day, without a boosting agent.”
Originally, Concert and Glaxo were counting on a different molecule, CTP-518, to be the lead contender in the HIV program. But CTP-298 “stood out as being preferable” in early human trials, Tung says.
What’s more, Tung says, CTP-298 has the potential to be useful in combination with Glaxo’s experimental treatment called GSK-572, which is an integrase inhibitor that’s now in Phase 3 trials. “Our eventual goal is to have a fixed-dose combo,” Tung says. He adds that Concert and Glaxo have been inspired by the success of Atripla, Gilead Sciences’ (NASDAQ: GILD) once-a-day combo of HIV treatments efavirenz, emtricitabine, and tenofovir disoproxil fumarate. Gilead’s product brought in sales of $2.9 billion last year. “That drug has been successful because it’s simple for patients to take,” Tung says.
Concert’s goal is to begin extensive human testing of CTP-298 next year. Tung says Concert and Glaxo are unable to predict the development timeline on the combo because they’re still working out the logistics.
To underscore the potential of its deuterium platform in other diseases, Concert also announced today that it had selected two other clinical candidates: CTP-499 for diabetic nephropathy and C-21191 for spasticity.
Patients with diabetic nephropathy—a type of kidney damage—are at high risk of needing dialysis or transplants. “This is a huge area because of the epidemic of diabetes,” Tung says. So Concert applied its deuterium technology to an existing drug that was originally designed to improve blood flow in patients with poor circulation. Concert’s scientists hope to prove that their deuterium-modified drug will combat the inflammation and tissue hardening that nephropathy causes.
Spasticity is a type of nerve pain that’s common in patients with multiple sclerosis, stroke, and other neurological disorders. C-21191 is based on an old discovery of a molecule that hits known receptors in the brain for modulating pain, but that’s useless because it doesn’t last long enough in the body. Tung says he hopes C-21191 will further prove that deuterium is “a way of rescuing drugs” that would otherwise be hampered by their short life in the human body.
Tung, a chemist by training, knows from experience that patience can pay off when it comes to studying entirely new therapeutic pathways. He once worked as a chemist at Cambridge, MA-based Vertex Pharmaceuticals (NASDAQ: VRTX), where he helped to invent technology used to create telaprevir, Vertex’s hepatitis C drug that was recently approved to huge fanfare.
“Seeing that go forward is very rewarding,” he says. Drug development, he concludes, “is long, arduous, difficult. Being innovative is what will keep this industry alive.”