Pazopanib (thyroïde)

Compte tenu des effets secondaires potentiels, les patients avec cancer de la thyroïde à croissance lente ne devraient pas utiliser le pazopanib
Le médicament peut aider à pazopanib révolutionner le traitement des patients atteints métastatique, à progression rapide des cancers différenciés de la thyroïde, affirment des chercheurs de la Mayo Clinic qui publient les résultats d'un essai clinique de phase II dans The Lancet Oncology.

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THURSDAY, April 7 (HealthDay News) -- Vandetanib has been approved by the U.S. Food and Drug Administration as the first drug to treat a rare form of thyroid cancer in its latter stages.


Le médicament Vandetanib a été approuvé par la FDA comme le premier médicament à traiter une forme rare de cancer de la thyroîde dans les stages avancés.

Medullary thyroid cancer accounts for 3% to 5% of the estimated 44,600 cases of thyroid cancer diagnosed each year in the United States, the FDA said in a news release. Typical symptoms include coughing, difficultly swallowing, thyroid enlargement, neck swelling, a lump on the thyroid and voice changes. Medullary thyroid cancer may occur spontaneously or be related to a genetic syndrome.

Le cancer de la thyroîde médullaire compte pour 3 à 5 % des 44,600 cas de cancer de la thyroîde diagnostiqués aux U.S.A chaque année

Vandetanib was evaluated in a study of 331 people with late-stage medullary thyroid cancer. Average progression-free survival among those who took the drug was 22.6 months, compared to 16.4 months among those who took an inactive placebo, the agency said.

(Sep. 17, 2010) — The drug pazopanib may help revolutionize the care of patients with metastatic, rapidly progressive differentiated thyroid cancers, say researchers at Mayo Clinic who are publishing findings of a phase II clinical trial in The Lancet Oncology.

Le médicament pazopanib pourrait aider à révolutionner les soins des patients aux prises avec un cancer métastasé à croissance rapide de la glande thyroîde.


The researchers studied 37 patients with the most aggressive form of this cancer -- developing in less than 5 percent of patients with differentiated thyroid cancer -- and found that about half (18) patients had a long-lasting response to pazopanib. Of that group, 12 are still alive without disease progression. The median progression-free survival time was 11.7 months, with an overall survival rate of 81 percent at one year.

Les chercheurs ont étudié 37 patients avec une forme agressive de ce cancer (moins de 5% des cancers de la glande thyroîde) et trouvé que 18 patients ont eu une répinse proongée au pazopanib. De ce groupe 12 sont encore vivants sans progression de la maladie. Le temps moyen de la survie sans progression a été de 11.7 mois avec une survie de 81% sur 1 an.

The researchers say that, to their knowledge, these findings represent by far the highest response rate yet reported in such aggressive cases of differentiated thyroid cancer. They caution however, that this drug is not meant to be used in slow-growing differentiated thyroid cancers and that they cannot assess the survival advantage pazopanib offers to the patients studied.

Les chercheurs disent que c'est de loin le plus haut taux de réponse à un médicament de la glande thyroîde.


Determining survival benefit would require a randomized clinical trial testing the agent, which inhibits all three vascular endothelial growth factor (VEGF) receptors, compared to other treatments or a placebo.

"In this group of patients, we would have expected the cancer to have progressed in everyone within six months, but instead the median time to progression was almost a year in response to pazopanib therapy," says Keith Bible, M.D., Ph.D., a medical oncologist and researcher who led the multicenter clinical trial, funded by the National Cancer Institute. Most of the patients treated were enrolled at Mayo Clinic campuses in Minnesota and Florida.

But as encouraging as this response is, it does not come without the potential for significant side effects, Dr. Bible says. The drug dose used in 16 patients had to be lowered because side effects were judged by oncologists to become potentially threatening or debilitating, and two patients experienced significant bleeding. Further, although two patients died in association with pre-existing disease while enrolled in the study, the agent could have contributed in some way, he says.

"Further studies of pazopanib in advanced thyroid cancer remain ongoing at Mayo Clinic and associated cancer centers to continue to learn more about how best to use the drug in these cancers," Dr. Bible says. "Such clinical trials also may provide patients access to this drug, which otherwise may be unobtainable due to cost, given that it is not yet approved for use in thyroid cancers."

De plus amples études sur le pazopanib pour la glande thyroIde restent en cours à la clinique Mayo.


Plans are underway for a larger phase III clinical trial with aggressive differentiated thyroid cancer patients that will be centered in Europe, with some sites to be opened in the U.S.

The authors declare no conflicts of interest. The manufacturer of pazopanib (GlaxoSmithKline) did not provide funding or other material support to the researchers and did not have access to the data.

(May 16, 2009) — A medication that helps stop the growth of new blood vessels has produced dramatic benefits for some patients with aggressive thyroid cancer, research from Mayo Clinic indicates.

Un médicament qui aide à arrêter la croissance de nouveaux vaisseaux sanguins a eu des effets remarquablement bénéfiques pour quelques patients avec un cancer de la glande thyroîde agressif.

At the annual meeting of the American Society of Clinical Oncology (ASCO), Mayo investigators report that cancer in about two-thirds of 37 patients with aggressive differentiated thyroid cancer treated with the drug pazopanib either stopped growing, or quickly shrank.

À peu près les 2 tiers des 37 patients traités avec le pazopanib ont vu leur tumeur soit arrêter de croître soit rétrécir.