Updated from 1:56 p.m. ESTShares of Keryx Biopharmaceuticals ( KERX) were among the best-performing health and pharmaceutical stocks Wednesday, rising 26.3% after the company said it plans to initiate a phase III trial for its diabetic nephropathy drug. The company said that no safety concerns were raised with either the 200-milligram or 400-milligram dosage of the drug during the company's most recent phase II trial. As a result, Keryx expects to begin studies of KRX-101 during a phase III trial within the next three months. Diabetic nephropathy is a life-threatening kidney disease that affects millions of diabetics. Shares traded up $2.95 to $14.18. Immunomedics ( IMMU) rose 6.8% after the company said its therapy to treat severe systemic lupus erythematosus received fast-track status from the Food and Drug Administration. Immunomedics plans to initiate a phase III trial during the first half of 2005. Shares traded up 21 cents to $3.28. Shares of Affymetrix ( AFFX) rose 5.9% after the company said its sales would exceed $100 million during the fourth quarter. Analysts polled by Thomson First Call expect the company, which makes chips used in genetic research, to post sales of $103.8 million. Affymetrix also said that sales for its next-generation products grew to over $10 million at the end of the fourth quarter. These products -- which the company expects to release and ship during the first half of fiscal 2005 -- include new genotyping arrays and automated instrument systems. Shares of Affymetrix traded up $2.01 to $35.95. Water Pik Technologies ( PIK) rose 3.3% after the maker of personal health care products said it is exploring various strategic alternatives to enhance shareholder value. These alternatives include selling a portion or all of the company. J.P. Morgan Securities is acting as financial adviser to the company. Shares traded up 59 cents to $18.57.