* 3rd-qtr earnings $1.30/share vs Street view $1.28
* Sales $9.77 bln vs Street view $9.93 bln
* Sales growth of top drug Humira slows
* Shares fall 4.2 percent
By Ransdell Pierson
Oct 17 (Reuters) - Abbott Laboratories Inc posted disappointing quarterly sales on slower growth of its top drug, arthritis treatment Humira, and provided new details of its planned split into two companies in January.
The diversified healthcare company, which sells traditional drugs, medical devices and nutritional products, also reported higher third-quarter earnings on Wednesday, beating expectations, despite a slight decline in overall sales.
Sales of Humira, by far its biggest product, rose 10.1 percent to $2.33 billion, a slowdown from growth of almost 17 percent in the prior quarter.
RBC Capital Markets analyst Glenn Novarro said Humira "came in $50 million light" due to weaker overseas sales.
Humira is expected to be the cornerstone of a planned spinoff on Jan. 1 of Abbott's branded drugs business into a publicly traded company called AbbVie, which will have annual revenue estimated at more than $18 billion.
The remaining Abbott, nicknamed "new Abbott," is expected to have 2013 sales of $23 billion from diagnostics, nutritional products, heart stents and generic medicines, Abbott said.
"Our shareholders will soon benefit from two fundamentally different investment opportunities with distinct strategic profiles and business priorities," Abbott Chief Executive Miles White told investors in a conference call.
But Novarro said Abbott officials spooked investors on the call by forecasting that AbbVie would have a tax rate of about 22 percent, instead of the mid-teens rate that Wall Street expected.
"So that dilutes the earnings power of the pharmaceuticals company," Novarro said. "There will be a little less enthusiasm for AbbVie." Consequently, Abbott shares were revalued lower on Wednesday, he said.
Abbott shares were down 4.2 percent to $69.08 in afternoon trading.
AbbVie will pay investors an annual dividend of $1.60 per share, while "new Abbott" will pay a dividend of 56 cents per share. Abbott previously said the combined dividends would at least equal the company's current annual dividend of $2.04.
Abbott said it earned $1.94 billion, or $1.21 per share, in the third quarter, compared with $303 million, or 19 cents per share, in the year-earlier period, when the company took a $1.4 billion litigation-related charge.
Excluding special items, Abbott earned $1.30 per share. Analysts, on average, expected $1.28, according to Thomson Reuters I/B/E/S.
Global sales fell 0.4 percent to $9.77 billion, short of Wall Street expectations of $9.93 billion. Sales would have risen 4.1 percent if not for the strong dollar, which lowered the value of sales in overseas markets.
Jefferies & Co analyst Jeffrey Holford said sales missed Wall Street forecasts due to pressures on Abbott's vascular, diagnostics and generic drugs businesses. He said tight expense controls enabled the company to beat earnings forecasts.
Abbott narrowed its full-year 2012 profit forecast to a range of $5.06 to $5.08 per share, from an earlier outlook of $5.00 to $5.10.
Revenue from Abbott's array of patent-protected prescription drugs, which it calls proprietary pharmaceuticals, rose 2.4 percent in the third quarter to $4.42 billion, while sales of nutritional products rose 4.5 percent to $1.6 billion. Growth in both categories slowed from the second quarter.
The company took a charge of $478 million in the latest quarter for new and previously announced restructuring activities across most of its businesses.
Company spokesman Scott Stoffel on Wednesday said the steps included layoffs of 550 people worldwide from the "new Abbott" business and another "several hundred" layoffs expected in 2013.
"Proprietary pharma, which will be AbbVie, is unaffected," he said. In all, he said the layoffs represent about 1 percent of Abbott's 91,000 employees worldwide.