The news sent the stock plunging, with shares down 65.5% to US$1.10 shortly after midday.
Pfizer Inc’s (NYSE:PFE) Viagra and Eli Lilly and Co’s (NYSE:LLY) Cialis are two of the best-selling ED drugs but they are associated with mild side-effects such as blurred vision and headaches, while other forms of treatment include injections and suppositories that must be inserted into the urethra.
Vitaros - which has been sold in Canada, Mexico, parts of the Middle East and much of Europe for several years by Apricus’ partner, Ferring International - is applied to the skin with a disposable applicator.
But the US Food and Drug Administration flagged safety concerns related to an ingredient in Vitaros - DDAIP.HCI - while it also identified deficiencies in its chemistry and manufacturing, the company said.
DDAIP.HCI helps absorb products into the skin and is a key part of Apricus’ drug delivery technology.
It’s not the first time the FDA has rejected Vitaros. Back in 2008 it refused to give the thumbs-up, with analysts noting that there were fears the treatment could cause cancer in patients or their sexual partners.
Had it have been accepted for sale in the US this time around, analysts reckon it could have raked in up to US$200mln a year within a few years of its launch.
Chief executive Richard Pascoe said the California-based firm will update investors in early March on its future plans for the drug.