Adams Respiratory Therapeutics Inc posted a quarterly loss, forecast its outlook for the year below Wall Street expectation and indicated that its key drug may face competition from a generic version.

Adams Respiratory shares fell more than 12 percent to $35.64 in midday trade on the Nasdaq.

The company said it was informed that Perrigo R&D Co, a unit of generic drugmaker Perrigo Co, had sought U.S. health regulators' approval for a copycat of Adams Respiratory's expectorant, Mucinex SE. The Chester, New Jersey-based company said it plans to vigorously defend its market position for the extended-release drug as well as the company's patent portfolio.

Mucinex is its biggest revenue generator for the company, contributing about 90 percent to its revenue. Besides Mucinex SE, it also sells the drug with different dosages of the main ingredient, guaifenesin.

Adams Respiratory has two patents, which expire in 2020, protecting its suite of extended-release guaifenesin products. The company said Perrigo's certification letter claimed the patents were invalid.

We do not believe we infringe any valid or enforceable claims of their patents, Perrigo spokesman Arthur Shannon said in an e-mail reply to Reuters.

Shannon also said Adams Respiratory, in its post-earnings investor call, did not commit whether it is going to file a suit to defend the patents.

Adams Respiratory did not immediately return calls and e-mails seeking comment.

In March, Adams successfully sued Mutual Pharmaceuticals Co and United Research Laboratories Inc after they sought regulatory approval for a generic version of Mucinex SE.

SWINGS TO LOSS

The company reported a loss of 3 cents a share for the fourth quarter, its third straight quarter of losses. Analysts on average were expecting its loss to be 4 cents a share. Revenue for the quarter was $46.9 million, exceeding expectations by $3 million.

For 2008, Adams expects earnings of $1.55 to $1.75 a share, reflecting higher revenue and expenses related to the launch and promotion of its new over the counter products and pre-launch spending for Mucinex with Codeine.

Analysts are expecting it to earn $1.90 a share.

New Jersey Medicine