Following up on a no confidence vote by an advisory panel, the FDA has formally requested more information from Cornerstone Therapeutics about a drug developed to treat low salt levels in blood.
Cornerstone (Nasdaq: CRTX) said Thursday it had received a formal Complete Response Letter from the FDA about its new drug application for lixivaptan.
“We are reviewing the Complete Response Letter and will determine the most appropriate next steps for the lixivaptan program,” said Craig Collard, Cornerstone’s chief executive officer. “We believe we have strong clinical data supporting lixivaptan for the treatment of hyponatremia and that a significant unmet need remains for an alternative vaptan in the hospital and community setting.”
The Cardiovascular and Renal Drugs Advisory Committee voted 5-3 on September to recommend rejection of lixivaptan as a treatment of hyponatremia, an electrolyte disorder characterized by low salt levels in the blood.
The independent panel also voted unanimously against approval of lixivaptan to treat low sodium in heart failure patients.
The FDA’s own staff review recommended lixivaptan approval to treat hyponatremia but not for hyponatremia associated with congestive heart failure.
An advisory committee’s recommendations are not binding to the FDA but are taken into account for approval decisions.
At that time, Collard said that the company respects the views of the advisory committee, which Cornerstone sees as another step in the process to bringing lixivaptan to patients.
“Cornerstone is committed to continuing to work with the FDA throughout the approval process building upon meeting our primary endpoint in each pivotal phase 3 trial,” he said.
Lixivaptan has been studied in three phase 3 trials. If the FDA decides lixivaptan needs more clinical studies, Cornerstone must decide whether to do lengthy and expensive clinical trials on the compound – something that runs counter to Cornerstone’s strategy. Rather than developing drugs in house, Cornerstone typically acquires drugs that are already commercialized or at least approved.
Cornerstone’s top-selling drug, Curosurf, was not developed by the company. Cornerstone acquired Curosurf’s rights in 2009.
Lixivaptan was the centerpiece to Cornerstone’s acquisition last year of Philadelphia company Cardiokine BioPharma, which had already taken lixivaptan through phase 3 clinical trials. While lixivaptan was not an approved drug, the compound was ready to be filed for review by the FDA. Hyponatremia affects up to six million people in the U.S. with direct medical costs estimated to range between $1.6 and $3.6 billion annually, according to Cornerstone.
Cornerstone, which started as a company focusing on respiratory therapeutics, has broadened its scope to include hospital-based drugs such as Curosurf. Lixivaptan was expected to give the company’s existing sales team yet another drug that could be sold to hospitals. Rather than adding sales staff for each new drug, Cornerstone’s strategy is to build a drug portfolio that it can sell to hospitals through its existing sales staff.
While Cornerstone has high hopes for the drug candidate, its success is also still important to Cardiokine shareholders. Cornerstone paid relatively little to acquire Cardiokine — $1 million at closing and the assumption of $2 million in Cardiokine’s debt, according to securities filings. The deal is heavily laden with milestones and Cardiokine shareholders will see more money only if the drug is commercialized and hits sales targets.
