Regulators and scientists seeking to explain the cases of red cell aplasia have focused on the Puerto Rico plant, and Johnson & Johnson's competitors _ mainly Amgen, of Thousand Oaks, Calif ., and Roche, of Basel, Switzerland _ say the problem is specific to Eprex, not to their EPO drugs.
32.
As mentioned earlier, the most common of those conditions is myasthenia gravis ( MG ); 10 15 % of patients with MG have a thymoma and, conversely, 30 45 % of patients with thymomas have MG . Additional associated autoimmune conditions include pure red cell aplasia and Good syndrome ( thymoma with combined immunodeficiency and hypogammaglobulinemia ).
33.
One clue may have been in the sharp rise in reported cases of red cell aplasia in 1999 . Johnson & Johnson had changed the manufacturing process at the Puerto Rico plant in 1998, ending the use of a human blood protein as a stabilizer in Eprex at the request of European health officials concerned about the spread of mad cow disease.
34.
J & J-BLOOD-DRUG ( Undated ) _ The discovery that scores of patients who have developed pure red cell aplasia, in which the body's germ-fighting defenses go haywire, had taken a drug made by Johnson & Johnson, has raised doubts about not just the company, but about a whole class of drugs that are a cornerstone of biotechnology.
35.
Other autoimmune diseases that have been treated with rituximab include autoimmune hemolytic anemia, pure red cell aplasia, thrombotic thrombocytopenic purpura ( TTP ), idiopathic thrombocytopenic purpura ( ITP ), Evans syndrome, vasculitis ( for example granulomatosis with polyangiitis, formerly Wegener's ), bullous skin disorders ( for example pemphigus, pemphigoid with very encouraging results of approximately 85 % rapid recovery in pemphigus, according to a 2006 study ), type 1 diabetes mellitus, Sjogren's syndrome, anti-NMDA receptor encephalitis and Devic's disease, Graves'ophthalmopathy, autoimmune pancreatitis, Opsoclonus myoclonus syndrome ( OMS ), and IgG4-related disease.
