LINDA A. JOHNSONPfizer Inc. said Tuesday that its first-quarter profit fell 19 percent, mainly because new generic competition to its blockbuster cholesterol pill Lipitor cut U.S. sales by 15 percent as the drugmaker offered big rebates and discounts to keep patients on its brand. The world's biggest drugmaker beat Wall Street's profit expectations but narrowly missed its sales forecast. It lowered its adjusted profit forecast for 2012 by 6 cents, to $2.14 to $2.24 per share. Analysts had predicted $2.26 per share. Including one-time items, it expects earnings per share of $1.23 to $1.38. New York-based Pfizer said the change was due to its recent decision to sell its infant-nutirition business to Swiss food and drink giant Nestle SA for $11.85 billion. The steep drop in Lipitor revenue was factored into its previous forecasts. The maker of Viagra said net income was $1.79 billion, or 24 cents per share, down from $2.22 billion, or 28 cents a share, a year earlier. Excluding one-time items, Pfizer would have made $4.43 billion, or 58 cents per share. Analysts were expected 56 cents a share. Revenue totaled $15.4 billion, down 7 percent from $16.5 billion a year ago. Analysts were expecting $15.46 billion. Sales in the U.S., where Pfizer's patent expired on Nov. 30 for Lipitor, the top-selling drug in history, fell to $5.95 billion, from $7.02 billion. International sales edged up 1 percent, to $9.45 billion. Lipitor sales fell 42 percent, to $1.4 billion from $2.39 billion. "I am pleased with out first-quarter 2012 financial performance, which was driven by growth in certain brands including Celebrex, Enbrel and Lyrica, growth in key geographies such as China" and cost-cutting, CEO Ian Read said in a statement. Revenue from prescription medicines fell 8 percent to $13.07 billion, as sales declined in the oncology, primary care and specialty care businesses.