By MATTHEW PERRONE AP Business Writer WASHINGTON (AP) — A marketing campaign for a GlaxoSmithKline prostate drug has drawn complaints from federal regulators, who said the space-themed advertisement is misleading. The British drugmaker's Avodart capsules treat symptoms of enlarged prostate, including frequent urination. In the company's advertisement, a man working on a model of the solar system is forced to stop painting to make frequent trips to the bathroom. A colleague then recommends he take Avodart, adding that "other medicines, they don't treat the cause, because they don't shrink the prostate." But FDA regulators say that claim is false. In a letter to the company's U.S. management, the FDA said Merck & Co. Inc.'s Proscar also reduces the size of the prostate, and has a similar indication. "Nothing in the labeling for Avodart suggests any specific advantage," states the FDA letter, which was posted online Friday. Regulators also take issue with the visuals used to promote the drug. At one point the ad shows a man holding a model of a planet which is quickly replaced with a much smaller planet, to demonstrate Avodart's prostate-shrinking power. The FDA says the visual exaggerates the drug's effect, which has been shown to reduce the prostates size about 25 percent after two years. "The planet shrinking in size represents a reduction in prostate volume that is much greater than the reduction actually achieved with Avodart," states the agency. The FDA's letter, dated last week, calls on the company to respond to the agency's concerns by March 4. Company spokeswoman Sarah Alspach said in a statement Friday the ad has not aired since last fall, and that the company "is committed to responsible marketing." The company's U.S. operations are based in Research Triangle Park, N.C. The FDA regularly issues warning letters to companies that do not follow regulations for manufacturing and marketing. The letters are not legally binding, but the agency can take companies to court if they are ignored. Avodart won approval in the U.S. in 2001 has become a strong revenue driver for Glaxo, the world's second-largest drugmaker. The company is also testing the drug as a preventive treatment against prostate cancer. Enlarged prostate affects half of men over 50 and 90 percent of men over 80.