Ensaio Clínico de Não Inferioridade e o Viés de Delineamento.

Um tema urgente a ser discutido na ANVISA, CONEP, CEPs, Universidades: o uso cada vez maior dos estudos de "não inferioridade". A motivação desses estudos é nobre, de início, porque seria realizado naquelas situações onde avaliar um novo medicamento contra o placebo seria anti-ético e, o tratamento corriqueiro traz muitos efeitos colaterais. Assim, admite-se que até o novo medicamento seja "discretamente" inferior ao tratamento usual. No entanto, essa prática está se disseminando abrindo brechas no famoso "good clinical practice". O tema merece muito mais. Uma revisão recente pode ser vista em www.annals.org/cgi/content/abstract/145/1/62 , publicada no Annals of Internal Medicine. Quem quiser o texto original pode requisitar a esse blogue.

Leiam abaixo essa notícia publicada no The Wall Street Journal, onde pela primeira vez se descreve um no tipo de "conflito de interesse": viés contra o delineamento de estudo!!

The Food and Drug Administration took the unusual step of removing a member of one of its influential advisory committees after the maker of a drug under consideration complained about a potential conflict of interest.Thomas Fleming, a prominent statistician at the University of Washington, said the FDA late last week rescinded his invitation to serve on a committee that yesterday reviewed a new use for Factive, an antibiotic made by Oscient Pharmaceuticals Corp. In a Sept. 1 letter, Oscient complained to the FDA that, among other things, Dr. Fleming was biased against a type of trial design the company used.

Continua o texto: " .....he might have a conflict of interest because he has publicly questioned tnoninferiority trial." In a noninferiority trial, used in FDA approvals of antibiotics, a new drug's efficacy has to be shown to be roughly equal to an old drug. Critics argue it isn't always clear how much better the old antibiotics are than placebo pills. So if a new drug is approved because its results are slightly, but not significantly, worse than those of an old drug, there is a risk that it hasn't actually done better than a sugar pillhe type of study used to prove Factive's efficacy, known as a sugar pill".