Chelsea Therapeutics International Ltd. CHTP +1.28% 's lead product candidate Northera received strong support from a U.S. Food and Drug Administration advisory panel, raising prospects the blood-pressure drug will receive approval from regulators.

The FDA had rejected Northera in March 2012 and asked Chelsea for more efficacy data on the medication. It accepted the resubmitted application in September, after more than a year of delays in the company's effort to bring its first treatment to market.

The resubmission included additional information to resolve certain technical deficiencies identified by the FDA, mostly related to the formatting of certain submitted electronic data sets and statistical programs.

Wedbush analysts on Wednesday said in a research note that the advisory panel's vote of 16 to 1 came despite the negative FDA tone in briefing documents. The firm said its impression was that "the panel came to appreciate the vagaries of clinical trials for neurological disorders especially in orphan diseases like symptomatic neurogenic orthostatic hypotension and the lack of good alternative treatments."

While the FDA doesn't have to follow the panel's recommendations, Wedbush said it thinks the "overwhelmingly positive vote this time may pressure the FDA to approve Northera."

An advisory panel had also recommended approval in February 2012—before the agency's previous rejection—but by a much smaller margin.

Wedbush said it estimates about a 65% chance of approval by Feb. 14 as a result of the overwhelming panel support, but added some concerns may linger that the FDA might require another trial to provide additional safety and durability data.

Northera was previously granted orphan-drug designation and received fast-track status from the FDA.