Targanta Aims to “Simplifi” Treatment of Deadly Bugs With Single-Shot Antibiotic

Xconomy Boston — 

Plenty of investors have been skeptical about Targanta Therapeutics’ claim that it has an antibiotic that can kill drug-resistant pathogens like MRSA with a single shot. That’s what the Cambridge, MA-based company (NASDAQ: TARG) claimed in a press release on Sept. 2, when the stock closed at $7.46. Since then, it’s dropped to $6.83 at the close Friday.

Still, the idea is intriguing, so I called CEO Mark Leuchtenberger to learn more about this drug, oritavancin, and where’s it’s headed. He talked about results from a mid-stage clinical trial called “Simplifi” which showed that a single dose, or a single dose followed by one follow-up five days later, was comparable to a three-to-seven -day course of therapy with the drug.

The company is saving the detailed results for an upcoming medical meeting, Leuchtenberger says. He won’t say when or where the data will be presented, but “it will be one of the big ones,” he says. If the data are persuasive to physicians and scientists at the meeting, the implications are big. A single infusion of the Targanta antibiotic would save a lot of time and hassle at hospitals, which treat the toughest bacterial infections with generic vancomycin in twice-daily infusions for 10 to 14 days, Leuchtenberger says. Another option, Lexington, MA-based Cubist Pharmaceuticals’ Cubicin, needs to be given in a regime lasting seven to 14 days, he says.

Even though Wall Street isn’t buying into Targanta’s results yet, the news is positive and “has to be viewed as modestly worrisome for Cubist investors,” said Thomas Shrader, an analyst with Rodman & Renshaw, in a note to clients. He added that Cubist has said almost half of its sales come from outpatient use of its drug, and that “single or infrequent dosing of oritavancin might someday trump this advantage and threaten the Cubicin franchise.”

“We think there’s potential here for a paradigm shift in the market,” Leuchtenberger says.

Oritavancin was originally developed at Eli Lilly (NYSE: LLY) in the 1990s, before the Indianapolis-based drugmaker decided to get out of the antibiotics business, Leuchtenberger says. The drug was passed on to Brisbane, CA-based Intermune (NASDAQ: ITMN), which ran out of money to develop it in 2003, which allowed Targanta to get hold of it, Leuchtenberger says.

The drug is attractive because it is extremely potent, meaning it can do the job of killing bacteria in a relatively low dose, and it has the ability to last in the body for about two weeks, Leuchtenberger says. It doesn’t get metabolized, and it is excreted through the bile ducts, not the kidneys like other antibiotics, he says, which means it’s unlikely to cause kidney toxicity.

The drug has hit its goals of treating infections in two pivotal trials, with the three-to-seven-day course of therapy, and Targanta has applied for FDA clearance to sell the drug in that form. The FDA’s deadline to complete its review is Dec. 8. Still, even if it presents positive data on the Simplifi trial, Targanta will need to do another pivotal trial in the single-shot form before it can market the drug for that purpose, Leuchtenberger says.

As long as the high-dose single shot doesn’t cause unusual side effects, then it should have an advantage because “the more drug you have in the body, the more chance you have to eradicate the bacteria in it,” Leuchtenberger says. In animal studies, the single-shot formulation was even better than the smaller doses spread over several days, the Targanta CEO says, and he notes that the data so far from humans “is consistent” with the findings in animals.

That sounds like a teaser of things to come.