WASHINGTON -- Drug companies Affymax Inc. ( AFFY) and Takeda Pharmaceutical Co. ( TKPYY) have issued a recall of their anemia drug Omontys after reports of severe allergic reactions in some kidney dialysis patients, including some deaths. The companies said that more than 25,000 patients have received Omontys, which is used against anemia in patients undergoing kidney dialysis. The companies said that 0.2% of the patients who have received the drug, or about 50, have reported severe allergic reactions and around 0.02% of patients, or about five, have died following their first dose of the drug. The serious hypersensitivity reactions occur within 30 minutes of the drug being administered for the first time. The companies said that no such reactions have been reported subsequent times that the drug is administered to a patient. The companies said that dialysis centers should stop using Omontys and that customers will be provided with instructions on how to return the product to the manufacturer for a refund. Customers with questions can call 1-855-466-6689 from 9:00 a.m. to 5:00 p.m. EST Monday through Friday. The two companies said they were working with the U.S. Food and Drug Administration on the details of the recall.