Baxter International Inc. (BAX) posted a 12% rise in third-quarter profit as margins rose despite flat revenue.

Earnings beat expectations, and the medical-products maker boosted its full-year outlook while also giving an upbeat fourth-quarter sales forecast.

Baxter now expects 2009 non-GAAP earnings of $3.79 to $3.81 a share, up from July's raised view of $3.76 to $3.80. It also expects sales growth of up to 1%, up from an earlier expectation for flat results.

Meanwhile, the company projected fourth-quarter non-GAAP earnings of $1.02 to $1.04 a share on sales growth of 8% to 10%. The mean estimates of analysts surveyed by Thomson Reuters was earnings of $1.04 and sales rising 6% to $3.33 billion.

Baxter's therapies target serious conditions that can't be ignored - such as cancer, immune disorders and trauma - insulating the company from the economy's woes. The company also has been developing a vaccine for the H1N1, or swine-flu, virus, amid a plan to increase research-and-development spending.

Baxter reported a third-quarter profit of $530 million, or 87 cents a share, up from $472 million, or 74 cents a share, a year earlier. Excluding costs from product discontinuation and other items, earnings rose to 98 cents from 88 cents. Baxter's July forecast was 95 cents to 97 cents.

Net sales inched up 0.2% to $3.15 billion, but rose 6% excluding currency changes. Analysts expected $3.19 billion.

Revenue rose 5% in the U.S. and 7% internationally, excluding currency fluctuations.

Gross margin rose to 51.9% from 48.3% amid the sales gains.

Baxter's bioscience business posted a 2% sales rise, or 8% minus foreign exchange, helped by strong results for recombinant and antibody therapies and other specialty plasma therapeutics. In September, the company said it expected to increase sales in the segment - which includes products for treating hemophilia and immune-system disorders - by 7% to 9% annually.

Shares closed Wednesday at $57 and didn't trade premarket. The stock is up 6.4% this year, trailing the broader market.

-By Mike Barris, Dow Jones Newswires; 212-416-2330; mike.barris@dowjones.com