The health care giant still hopes to put a sudden end to premature ejaculation. Despite being rejected by the FDA four years ago, Johnson & Johnson plans to seek approval to sell dapoxetine in Europe and Canada later this year, and continues to mull over plans to gain US clearance.

With new trials completed in Europe and Asia, the total number of men tested is now about 5,000. Paul Stoffels, a J&J research executive, recently told reporters that the new studies “confirmed the safety and efficacy profile” of dapoxetine, and that the drug was well-tolerated and side effects were mild to moderate, according to The Wall Street Journal (subscription required).

Some may argue whether treating premature ejaculation constitutes a medical benefit. But with an estimated 20 percent to 30 percent of men involuntarily doing the quickie, Morgan Stanley foresees a $600 million market by 2011, assuming J&J prevails in the US, the paper writes. After all, online shoppers compare prices on erectile dysfunction meds more than any other type of drug, according to pharmacychecker.com.

So it’s hard to imagine, pardon the pun, that dapoxetine wouldn’t generate lasting interest.