Glivec. Glivec® is an innovator drug used to treat chronic myeloid leukemia. In the last two and a half years, case studies involving comparatively well-off patients from middle-income countries have demonstrated that copy drugs are ineffective in treating chronic myeloid leukemia in some patients. These copy medications are not proven generics and are not required to pass stringent bioequivalence tests prior to use in hospitals and pharmacies. Some of these medications, such as Imatib, are produced by large reputable pharmaceutical manufacturers--in this case India's Cipla, whose pharmaceuticals regularly pass FDA inspections and meet international regulatory standards (none of Cipla's antibiotics or antimalarials failed basic tests in our study discussed above).
While Glivec® has demonstrated a "high hematologic, cytogenetic, and molecular response rate and favorable long-term safety profile," five reported case studies suggest that copy versions, which contain a slightly different version of the active ingredient, are ineffective in some cases. In all five studies, the patient experienced a relapse after switching from the original to the generic medication, and then improved again when put back on the original drug. In one case, an older patient in fragile condition was unable to recover even after the reintroduction of the innovator drug, and he died after the reintroduction.