[NEW YORK] US stocks opened higher on Wednesday as news of a large biopharmaceutical merger offset lacklustre data on private-sector hiring.
Five minutes into trade, the Dow Jones Industrial Average was at 18,010.74, up 82.54 points (0.46 per cent).
The broad-based S&P 500 gained 7.35 (0.35 per cent) at 2,096.81, while the tech-rich Nasdaq Composite Index advanced 17.36 (0.35 per cent) to 4,956.69.
Alexion Pharmaceuticals announced it would buy Synageva BioPharma for US$8.4 billion, creating a bigger player in treatments for rare diseases.
Payrolls firm ADP estimated the US added just 169,000 private-sector jobs in April, the second month in a row under 200,000, as the petroleum sector downturn continued to pinch the labour market.
Investors are looking ahead to Friday's US Labour Department jobs report for April.
US stocks fell sharply on Tuesday on worries about higher oil prices and the ongoing Greek debt crisis.