sexta-feira, 19 de janeiro de 2007

A volta dos não foram embora: Cox-2 ou The Empire strikes back.

Confesso o meu cansaço em discutir "reposição hormonal" e, também "cox-2". Gostaria de falar sobre antihipertensivos, mas a Big Pharma não permite. Abaixo, texto do The Wall Street Journal sobre a volta dos que não foram. Destaco o seguinte parágrafo:
Novartis began quietly selling Prexige in 2005 while the other Cox-2s battled controversy. It launched the drug first in Brazil and later in the United Kingdom and Australia. Last year, Novartis received regulatory approval to begin selling Prexige across Europe. The drug's global sales last year climbed to $47 million from $8 million in 2005, Novartis said in its year-end financial results.
Drug Makers TryTo Bring BackCox-2 Inhibitors
By JEANNE WHALENJanuary 19, 2007; Page B1
Two years after
Merck & Co. was forced to pull the painkiller Vioxx from the global market because of cardiovascular side effects, pain pills in the same class -- known as Cox-2 inhibitors -- are quietly attempting a comeback.
Drug giant
Novartis AG yesterday said that it will start selling its Cox-2 inhibitor Prexige across Europe in coming months, and that it has completed the clinical trials necessary to resubmit the drug for U.S. Food and Drug Administration review this year. Thomas Ebeling, chief executive of Novartis pharmaceuticals, said the company hopes to begin selling Prexige in the U.S. by the first half of 2008, adding it believes Prexige can eventually attain global sales of $500 million to $1 billion a year.
That followed Merck's statement in November that it plans to seek FDA approval for Arcoxia, a Cox-2 inhibitor that the company already sells in Europe and other countries outside the U.S. Last August, Merck released preliminary data that suggested Arcoxia doesn't carry more cardiovascular risks than diclofenac, an older pain drug. However, some doctors said the study's data was limited and questioned the comparison of Arcoxia to diclofenac, which they say acts like a Cox-2 inhibitor in the first place -- rather than comparing it to a less-similar painkiller such as naproxen, sold under the brandname Aleve.
Cox-2 inhibitors were designed to be easier on the stomach than older pain pills such as ibuprofen and naproxen, which are associated with gastric bleeding in some patients. But several of the Cox-2 drugs became mired in safety scandals. Merck withdrew Vioxx from the global market in the fall of 2004 after a study showed it elevated patients' risk of heart attacks and strokes. In April 2005,
Pfizer Inc. pulled its Bextra pain reliever from most markets world-wide amid FDA concerns about the drug's safety. Merck and Pfizer are still fighting big lawsuits from patients who took the pills. In the U.S., Pfizer's Celebrex is the only Cox-2 remaining on the market.
Some experts think the new Cox-2 drugs face a high regulatory hurdle in the U.S., given the legacy of their predecessors. "Things have changed dramatically in terms of FDA oversight, in part because of Vioxx and Bextra," says James Kirkpatrick, assistant professor of medicine in the University of Pennsylvania's cardiovascular division. "It's certainly a risky move to invest a lot of effort into it."
If the drugs don't get approval to be sold in the U.S., they will face an uncertain fate. Cox-2 drugs have sold in only small amounts in Europe, where governments have steered patients to cheaper, older drugs such as diclofenac and naproxen.
But some big drug makers believe there is still a market for Cox-2s that can prove themselves safe and effective -- particularly for pain sufferers with gastrointestinal problems.
"If you believe in one of your products, you have to be resilient," Novartis chief executive Daniel Vasella said in an interview.
Novartis spoke about its plans for Prexige as it reported that fourth-quarter net profit rose 23% to $1.66 billion from $1.35 billion in the year-earlier quarter, driven by strong sales of blood-pressure pill Diovan and cancer drug Gleevec. Sales increased 16% to $10.05 billion from $8.66 billion.
Novartis began quietly selling Prexige in 2005 while the other Cox-2s battled controversy. It launched the drug first in Brazil and later in the United Kingdom and Australia. Last year, Novartis received regulatory approval to begin selling Prexige across Europe. The drug's global sales last year climbed to $47 million from $8 million in 2005, Novartis said in its year-end financial results.
Novartis submitted Prexige for U.S. approval in 2002, but the FDA asked for additional safety and efficacy studies. In particular, the FDA was concerned that some patients taking a 400-milligram dose of Prexige showed signs of liver toxicity. The agency asked Novartis, based in Basel, Switzerland, to study the drug at a lower, 100-milligram dose. It was also concerned that Novartis hadn't studied the drug in enough overweight people and asked for an additional clinical trial in overweight Americans with osteoarthritis of the hip.
Novartis has now completed those studies and plans to submit them in the coming months to the FDA, which is likely to give the drug a tough review. To simplify its application, Novartis will for now ask the agency to approve Prexige for osteoarthritis only and not for acute pain, a second indication that it originally hoped to gain, said James Shannon, head of pharmaceutical development at Novartis.
Pfizer has made a major effort to reintroduce Celebrex to doctors and to revive direct-to-consumer advertising for the drug, causing sales to rebound after a steep fall in 2005. In the third quarter of last year, global sales reached $537 million, up 20% from the year-earlier quarter. Pfizer said at the time it expects 2006 sales to hit $2 billion, up from $1.7 billion the year before. Nonetheless, those numbers are significantly down from Celebrex's $3.3 billion in 2004 sales.
Merck said it will also seek a narrower FDA approval for Arcoxia than it had previously sought. Merck plans to ask for permission to sell Arcoxia to treat symptoms of osteoarthritis. Previously, it had sought approval for a range of uses, including treatment of rheumatoid arthritis.

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