Health care products maker Abbott Laboratories on Monday said it will acquire the drugmaker Kos Pharmaceuticals Inc. for about $3.7 billion in cash to expand it cholesterol drug holdings.

Abbott plans to buy Kos for $78 per share, a 56 percent premium on its closing price Friday at $50.09 on the Nasdaq Stock Market.

Kos, based in Cranbury, N.J., is a specialty drugmaker whose main product is Niaspan, which raises levels of "good" cholesterol. Kos booked 2005 revenue of $751.7 million.

Abbott, based in North Chicago, Ill., expects the transaction to depress earnings by 2 cents to 3 cents per share in 2007, have a neutral impact on profit in 2008 and add to earnings thereafter.

Abbott shares dipped to $46.85 in electronic premarket trading from their close Friday at $47.64 on the New York Stock Exchange.