Ending the Suspense, Celladon’s Gene Therapy Helps Heart Failure Patients in Small Study

for the health of heart failure patients—how far they could walk in a six-minute period, how well their hearts pumped blood, how much time they spent in the hospital, and whether biomarkers could confirm these clinical readings at the molecular level.

Specifically, over the six-month study period, patients on the high dose of Celladon’s treatment spent an average of 0.2 days in the hospital, compared with 2.1 days for those on placebo. Patients who completed the six-minute walk test were able to walk one extra meter after six months of taking the Celladon treatment, compared with an 87-meter decline in walking distance for those on placebo, researchers said. Patients on the Celladon treatment had an improved score after six months on a common blood biomarker of heart failure, while they got worse on that reading if they took a placebo. The same pattern was true when researchers look at quality of life questionnaires—patients on the Celladon treatment said they felt better, and the placebo said they felt worse.

Any single one of those data points in isolation could be dismissed as a fluke, Greenberg says. But the fact that all of these readings reinforced each other in a positive way ought to be an encouraging sign that these results can be duplicated in an even more rigorous Phase III clinical trial, he says.

The main objection to this study will be its small size, Greenberg says. There were low, medium, and high-dose groups on Celladon’s Mydicar, plus a placebo group—meaning that in a study of 39 patients, only about 10 people were in each cohort. Such small numbers mean it couldn’t be proven to be statistically significant, but it did appear that people who got the higher dose of Celladon’s drug did better than those who got a lower dose—always an important sign. And when asked about side effects, he had nothing to report.

“We saw nothing in patients treated with meds that seems unusual. The drug didn’t appear to be doing anything untoward,” Greenberg says.

For Celladon as a business, this translates into a whole set of new options. CEO Krisztina Zsebo knows she needs 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. That will take money. It could come via a partnership, more venture capital, or an acquisition, Zsebo has said. It will be interesting to see which door Celladon and its backers—Venrock Associates, Enterprise Partners Venture Capital, and Johnson & Johnson Development Corporation—choose to open.

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.