Celladon’s Gene Therapy Passes Heart Failure Trial; Maintains Suspense on Details

has just five employees. The company raised $2.8 million when I last wrote about the company in September, which essentially was like adding a little gas in the tank so it could drive the car to this vital destination. The company has secured a total of $61 million since it first raised money in 2004, from investors that include Enterprise Partners Venture Capital, Venrock Associates, and Johnson & Johnson Development Corporation.

It’s kind of hard to ask about the next steps for Celladon when I can’t even see the data yet, but I asked anyway. The company is considering its options for getting more cash, which it will certainly need to run a pivotal, Phase III clinical trial that the FDA will require before the gene therapy can be sold to patients in the U.S. The options include a partnership, more venture capital, or an acquisition, Zsebo says.

Celladon has a clinical trial designed and is almost ready to approach the FDA and ask for regulators to agree on whether it’s a valid approach for the next phase of trials. The budget of this trial will depend on how many patients the company needs to enroll to satisfy the FDA. Celladon is hoping the agency won’t require huge numbers of patients—which would require more time and money—because it has already cleared a difficult statistical hurdle by showing a benefit in a small group of patients.

“We believe the data we have now are strong enough that we’ll get a priority review,” Zsebo says, meaning the FDA might offer a faster-than-usual six-month review cycle for this drug’s application. The FDA sometimes does that for treatments with life-saving potential.

No matter how much buzz the company generates in the scientific community, such a treatment is still a long way from being commercially available. Celladon hopes the pivotal trial could start sometime in the second quarter of 2011, Zsebo says, and it will require one year of patient follow up. Given how long it might take to fully enroll patients, she didn’t want to guess when the company would be ready to submit an application for FDA approval.

Zsebo, a biochemist by training who previously worked at Cell Genesys and Amgen, has heard every skeptical remark in the book about gene therapy. Can you deliver it efficiently throughout tissues where it needs to go? Can the gene get into cells, and properly express the functional protein? Is it safe?

She sounds ready to make her case on the potential benefit to patients and society at large, if this treatment can make it through the FDA. She pointed out that congestive heart failure costs the U.S. health system an estimated $39 billion a year. A lot of gene therapy products have been tested for rare genetic diseases, not a mass-market problem like this.

“This is by far the largest population for a gene therapy candidate,” Zsebo says. “This could have a very big footprint.”

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.