Ensemble Therapeutics Builds Super-Sized Library of Mid-Sized Drugs

if certain new drugs can hit a target, and can elicit the desired biological activity.

“We’ve become very productive, we can screen millions of macrocycles against dozens of targets in a short period of time. It’s extremely efficient and fast,” Taylor says.

Taylor has his Ph.D in medicinal chemistry and prior experience as a senior vice president of R&D at Pfizer, so he knows how this is easy to say and hard to do. He’s been joined in this effort by Nick Terrett, Ensemble’s chief scientist, another Pfizer veteran, and a co-inventor of the hit erectile dysfunction drug, sildenafil (Viagra).

Taylor and Terrett know from experience that Big Pharma companies have huge libraries of small molecule compounds of their own. For Ensemble to really have something new and valuable, it has to bring new molecular structures to the table, with ability to hit new targets. And it needs to be done cheaply, because R&D costs have been rising, without extra productivity to show for it. Big Pharma, as those who follow the headlines know, has been under a lot of pressure to get more bang out of its research bucks.

“Big pharma had so many compounds in its collections, it was getting too expensive to screen,” Terrett says. Taylor adds that it could sometimes cost $3 million to $4 million to screen an entire library of small molecules against a biological target of interest, just looking for hits, before even starting the long and expensive work of animal and human testing. Ensemble’s synthetic macrocycles are now made for just 9 cents each, Terrett says.

Of course, nobody knows whether those 9 cent molecules will ever go on to become FDA approved products worth hundreds of millions, or even billions. Ensemble did, in the last year, change its name from Ensemble Discovery to Ensemble Therapeutics, so that’s a pretty clear indicator of what it wants to grow up and become. Ensemble currently has 15 protein targets at various stages of test development, screening, and validation of “hits.” It will soon take the next steps by picking one or two lead drug candidates, Taylor says.

“Over the next year or so, that’s where the progress of the company will be most dramatic,” Taylor says.

Ensemble is still playing a lot of its cards quite close to the vest, partly because of agreements it has made with partners. On my recent visit to Ensemble’s offices, Taylor did say that the company received a milestone payment from its partner Bristol-Myers for developing a macrocycle molecule that was able to bind with two targets at the nexus of a protein-protein interaction. Another program is seeking to hit an interaction between a protein known as a cytokine and a cytokine receptor, Taylor says.

He didn’t name the targets, and the company hasn’t published any description to peers of what it has done with macrocycles against these specific targets. That could change over time, Taylor says. “We plan to publish and disclose our work on those targets so that people can understand the power of what we can accomplish,” Taylor says.

Ensemble isn’t the only company with its eye on macrocycles. Research Triangle Park, NC-based Tranzyme Pharma (NASDAQ: [[ticker:TZYM]]) has built its own library of macrocycle compounds, which it described in its recent IPO filings to investors. Ensemble believes that it has a much bigger library of macrocycles with more diversity of structures, Taylor says. None of the Big Pharma companies, and no other biotech company, has a library like Ensemble’s in their toolkit, he says.

Pharma has already shown a fair bit of interest in breaking out of the rut of small vs. large molecules, by ponying up for partnerships to develop RNA interference drugs, or peptide therapies as alternatives to the standard fare. That same kind of desire—to find new compounds that can hit currently inaccessible biological targets—is working in Ensemble’s favor. “There’s a lot of interest in Big Pharma in what we’re doing,” Taylor says.

Author: Luke Timmerman

Luke is an award-winning journalist specializing in life sciences. He has served as national biotechnology editor for Xconomy and national biotechnology reporter for Bloomberg News. Luke got started covering life sciences at The Seattle Times, where he was the lead reporter on an investigation of doctors who leaked confidential information about clinical trials to investors. The story won the Scripps Howard National Journalism Award and several other national prizes. Luke holds a bachelor’s degree in journalism from the University of Wisconsin-Madison, and during the 2005-2006 academic year, he was a Knight Science Journalism Fellow at MIT.