* TSX down 22.77 points, or 0.18 percent, at 11,927.49 * Banks and oil companies push index lower * Valeant surges 15 pct after announcing acquisition By Alastair Sharp TORONTO, Sept 4 (Reuters) - Canada's main stock index edged lower on Tuesday morning, weighed down by heavyweight energy and financial stocks and shrugging off a surging Valeant Pharmaceuticals International Inc which said it would buy a rival. Shares in Valeant, the largest publicly traded drug maker in Canada, jumped more than 15 percent to C$58.33 after it announced a $2.6 billion deal to take over U.S. dermatology competitor Medicis Pharmaceutical Corp. Valeant has been on an acquisition spree since its 2010 takeover by Biovail Corp, preferring growth through acquisitions to heavily spending on research. But the broader market was sluggish, with mining and energy companies among the biggest decliners despite investors widely expecting U.S. and European monetary easing that would boost appetite for commodities. Financial stocks also pushed lower, with Royal Bank of Canada down 0.7 percent at C$54.78. The banks gained last week on surprising robust profit and dividend increases. At 10:52 a.m. (1452 GMT) the Toronto Stock Exchange's S&P/TSX composite index was down 22.77 points, or 0.18 percent, at 11,927.49. The president of the European Central Bank, Mario Draghi, told European lawmakers that purchases of short-term sovereign bonds would not breach European Union rules, according to a recording obtained by Reuters. "You would think that commodity stocks and the cyclical stocks would try to rally strongly on the back of that and you're not seeing that kind of participation from these sectors," said Sid Mokhtari, director of institutional equity research at CIBC World Markets. That is partly because miners and oil companies have already enjoyed a recent rally, he said. "People bought ahead of the news -- the buy the rumor, sell the news assumption," he said. The energy sector has gained 7.3 percent in the past three months, the best performance of any of the top ten groups on the index. Adding to worries, manufacturing data out of the United States showed a third straight month of contraction in August.