On October 3, 2005, WLF wrote to DDMAC, calling on DDMAC to withdraw a warning letter sent to Nephrx, LLC on September 30, 2005 regarding Nephrx’s allegedly improper promotion of Calcitriol on Nephrx’s web site and in print advertisements. Calcitriol is a drug used to treat hypocalcemia in patients undergoing chronic renal dialysis. DDMAC alleged that the advertisement and web site lacked risk information about Calcitriol, and made unsubstantiated superiority claims. WLF’s response took particular issue with DDMAC’s demand that Nephrx disseminate “corrective” promotional messages; WLF noted that FDA lacks statutory authority to require “corrective” messages, and that in any event such a demand violates the First Amendment. WLF also faulted DDMAC’s finding that the advertisement lacked adequate risk information, noting that the ad included risk information virtually identical to the language approved by FDA and set forth in the package insert.