June 19 (Bloomberg) -- GlaxoSmithKline Plc is struggling to build sales of its year-old migraine medicine Treximet as doctors and insurers object to the cost, calling the pill no better than the two generic drugs it combines.

Treximet pairs Glaxo’s migraine pill Imitrex, whose U.S. patent ran out in February, with the anti-inflammatory drug naproxen, available without a prescription. The expense of those two generics together may soon fall to $5 a dose, said Tim Heady, chief of the pharmaceutical solutions unit for UnitedHealth Group Inc., which refuses to pay for Treximet on most of its plans. Treximet costs the top U.S. health insurer $18 a pill.

Glaxo and other drugmakers facing the loss of sales as a patent expires on a popular medicine may release a new version that’s longer acting, or combines two drugs in one pill, Heady said. While these companies say such reformulations are better than their predecessors that have gone generic, insurers and doctors aren’t convinced they’re worth the price.

“There is nothing in Treximet that one can’t get for significantly less dollars,” Heady said in a telephone interview. “There are instances where drugs are being brought to market that really aren’t different or offering any real benefit from a clinical or cost perspective. In those instances, it makes sense not to cover the drug at all.”

When a medicine’s patent expires, a drugmaker may lose as much as 80 percent of sales to generic copies. Getting U.S. Food and Drug Administration approval for a reformulated drug lets companies sell the new version with a fresh patent, according to U.S. guidelines.

Added Costs

Such reformulations add to costs for patients, governments and businesses, Jerry Avorn, a physician and professor at Boston-based Harvard Medical School who studies medical cost effectiveness, said a telephone interview.

“In these times, when people are trying to scrape together enough money to pay for their medicines, not to mention their mortgage and their meals, it is absurd to combine two generics and try to sell it for this price,” Avorn said.

Treximet is superior to Imitrex, said Stanley Hull, Glaxo’s senior vice president of U.S. pharmaceuticals.

“We have definitely been meeting resistance in the marketplace in this whole movement to try to use more generic medicine, and it is a disadvantage to patients who suffer from debilitating headaches,” Hull said.

Glaxo, based in London, increased 2 pence, or less than a percent, to 1,115 pence in London trading yesterday. The company rose 1.2 percent over the 12 months before today.

Refused Coverage

Treximet isn’t the first drug to be deemed too costly for coverage by UnitedHealth. The insurer, based in Minnetonka, Minnesota, also refused to pay for AstraZeneca PLC’s Nexium, for heartburn, and Schering-Plough Corp.’s allergy pill Clarinex, a replacement for Claritin, because there are cheaper alternatives, Heady said.

“There are clearly practices that don’t add value to health care, but I don’t begrudge the pharmaceutical manufacturers from looking for ways to protect the brand,” Heady said. “It is just natural. The question is, what can United do to help our customers and our members continue to have affordable access to the drugs they need?”

AstraZeneca developed Nexium, similar to its heartburn drug Prilosec, which lost patent protection. Prilosec is now priced at about 60 cents a pill while Nexium costs about eight times as much on Drugstore.com. Blair Haines, a spokesman for AstraZeneca, said the London-based company performed 12 studies showing Nexium controls gastric acid better than Prilosec.

Patient Choice

Schering-Plough Corp.’s Clarinex, sold by Drugstore.com for about $4.00 a pill, and Claritin, costing about $1 a pill and available in generic form, are both antihistamines. It’s important for patients to have many choices of allergy medicines because individual responses to medications differ, said Julie Lux, a spokeswoman for Kenilworth, New Jersey-based Schering- Plough.

Glaxo introduced Treximet in April 2008, promoting it as an improved version of the best-selling Imitrex, with $1.26 billion in sales last year.

It’s more convenient for patients to swallow a single pill, and the ingredients are absorbed faster than if they were taken separately, said John Plachetka, chairman and chief executive officer of Pozen Inc., of Chapel Hill, North Carolina, one of the developers of Imitrex. Glaxo licensed the drug from Pozen in 2003.

Francis Conidi, director of the Florida Center for Headache and Neurology, in Port Saint Lucie, Florida, said he isn’t sold on Treximet’s virtues.

Health Risks

The drug may increase a patient’s risk for heart attack, stroke and stomach ulcers, side effects associated with naproxen, which is sold in drugstores as Aleve by Bayer AG of Leverkusen, Germany, Conidi said.

“It is just no better than combining Imitrex and Aleve,” the physician said. “If I don’t have a coupon for Treximet I’ll ask what the co-pay is, and if it is high I wouldn’t have the patient try it.”

The headache specialist declined an offer by Glaxo, at a medical conference in Dallas, to pay him $750 for giving a one- hour talk on Treximet with company-provided slides and $1,000 for longer presentations, Conidi said. Glaxo said in an e-mailed statement that the speaking fees vary, and that doctors “provide legitimate and important insight and expertise into medical care that helps us meet patients’ needs.”

Glaxo, with $35.8 billion in revenue last year, needs new treatments. Cheaper generic copies eroded U.S. sales of at least four of the company’s medicines last year and safety concerns dragged down demand for the diabetes drug Avandia, said Navid Malik, an analyst at London-based Matrix Corporate Capital Ltd.

Reduced Expectations

Malik said he originally projected Treximet might generate sales of about $650 million annually by 2015. Now he’s estimating it may bring in about half as much because of price resistance.

Studies funded by Glaxo and published in the Journal of the American Medical Association in 2007 found that Treximet stopped migraine headaches after two hours in as many as 65 percent of patients, compared with 55 percent on Imitrex alone and 44 percent on naproxen.

“The whole issue of looking to shave costs has gotten in the way of providing the best medicine for people,” Pozen’s Plachetka said.

Treximet sells for about $22 a pill in a pack of nine tablets through the online pharmacy Drugstore.com. CVS Caremark Corp., based in Woonsocket, Rhode Island, charges $23 a pill.

Price Comparisons

UnitedHealth covers Treximet only on certain Medicare plans. Other insurers have tried to discourage patients from using Treximet by making it more expensive. Aetna Inc. of Hartford, Connecticut, WellPoint Inc. of Indianapolis, and Cigna Corp. of Philadelphia all say they require the highest patient contribution level for Treximet.

Efforts by drug companies to compete against generic brands may lose traction under the American Recovery and Reinvestment Act of 2009, passed in February, which allotted $1.1 billion for comparing the effectiveness of medicines, said David Certner, legislative policy director for the Washington- based AARP, the largest U.S. membership organization for people over age 50.

Drugmakers, including Merck & Co. of Whitehouse Station, New Jersey, said they support this research, called comparative effectiveness, as long as it doesn’t result in the government’s mandating which medicines doctors can prescribe.

“In some cases you may be paying a lot more for a drug that is no more effective,” Certner said. “We don’t have very good data right now on how some of these things actually work. You have all these studies to get the drug on the market, but very little post-market.”

To contact the reporter on this story: Shannon Pettypiece in New York at spettypiece@bloomberg.net

Last Updated: June 19, 2009 00:01 EDT