By Ben Butkus
Catalyst Pharmaceutical Partners said yesterday that it has exclusively licensed from Northwestern University the commercial rights to GABA aminotransferase inhibitors and derivatives of the anti-epileptic drug vigabatrin.
Catalyst, based in Coral Gables, Fla., said the compounds may have applications for a broad range of neurological diseases, including addiction and epilepsy, and has identified and begun to develop an undisclosed, lead oral compound.
In addition, the new compounds may be more potent and induce fewer side effects than a current vigabatrin derivative that Catalyst licensed exclusively from Brookhaven National Laboratory and is currently shepherding through clinical trials, Catalyst CEO Patrick McEnany told BTW this week.
Under the terms of its agreement with Northwestern, Catalyst has obtained an exclusive, worldwide license to a pair of composition-of-matter patents and one patent application related to the new class of inhibitors.
Catalyst will be responsible for continuing research and development of any resulting product candidates. Meantime, Northwestern will receive an undisclosed upfront payment, clinical development milestone payments, and royalties on resulting products. Additional terms were not disclosed.
Richard Silverman, a professor of chemistry at Northwestern, led the group of scientists that discovered the new vigabatrin derivatives. Silverman holds 41 patents and is best known as the inventor of pregabalin, a blockbuster fibromyalgia drug sold by Pfizer under the brand name Lyrica.
In late 2007, Northwestern sold an undisclosed portion of its worldwide Lyrica royalty rights to Royalty Pharma $700 million, considered to be one of the largest royalty monetization deals in history for a university-developed technology (see BTW, 1/9/2008).
McEnany told BTW that Catalyst identified Silverman's lab as a potential partner because of his expertise in GABA-related pathways and specifically his work in the area of GABA aminotransferase inhibitors.
In 2002, Catalyst exclusively licensed from Upton, NY-based Brookhaven National Laboratory the rights to vigabatrin to develop treatments for all forms of drug addiction, such as cocaine or methamphetamine addiction, as well as obsessive compulsive disorders.
That drug candidate, which Catalyst calls CPP-109, has just finished a phase II clinical trial, McEnany said, although the company has yet to compile and analyze data from the study. Catalyst first submitted an investigational new drug application to the US Food and Drug Administration to evaluate CPP-109 to treat cocaine addiction in 2004, and the compound has been stuck in clinical trials ever since.
"In digging deeper and looking to find other GABA aminotransferase inhibitors, one of our [scientists] came across some work [Silverman] was doing at Northwestern," McEnany said. "We determined that this was pretty much the only other GABA aminotransferase inhibitor available, and … decided to pursue it further."
Catalyst said that the new class of GABA aminotransferase inhibitors was demonstrated to be at least 200 times more potent than CPP-109 in in vitro enzyme inhibition kinetics studies. This increased potency could enable the development of superior or alternative dosage forms compared with CPP-109, the company said.
In addition, the new compounds may also have superior specificity to GABA aminotransferase and, possibly — "though we haven't proven this yet," McEnany said — a better side effect profile compared to CPP-109.
Lastly, the composition of matter patents for the new compounds will ensure the company exclusivity well beyond the expected exclusivity for CPP-109, and allow Catalyst to explore broader CNS applications such as the treatment of epilepsy, the company said.
Despite these potential benefits, Catalyst's licensing deal with Northwestern is not expected to diminish the value of its previous deal with BNL, primarily because even the first-generation compound "will take a fair amount of time to develop," McEnany said.
McEnany added that the company's licensing agreement with Northwestern was also "a strategic acquisition," financially speaking. To wit, he pointed to the fact that the FDA just last month granted a pair of NDAs to Danish pharma Lundbeck for use of vigabatrin to treat infantile spasms and refractory complex partial seizures in adults.
Sanofi-Aventis has marketed vigabatrin outside the US for many years, and Ovation Pharmaceuticals had been developing it under the brand name Sabril since acquiring the US marketing rights in 2004. Earlier this year, Lundbeck acquired Ovation for $900 million, about $300 million of which was contingent upon the Sabril regulatory milestones announced last month.
"These are different indications, so there are no violations of our patents, and we don't violate what they're doing," McEnany said. Still, he said the Lundbeck-Ovation sale demonstrated the huge potential payoff for next-generation vigabatrin derivatives.
Catalyst plans to continue working with Silverman's lab at Northwestern to develop the new treatment, "probably" under some form of sponsored research, McEnany said.
"I can't say definitively," he said, "but it would make a lot of sense. We expect to be involved further with Dr. Silverman on the development of this compound."