NEW YORK (CNN/Money) - The Food and Drug Administration rejected Johnson & Johnson's application to expand Risperdal, one of its top-selling drugs, into treatment for autism, but an analyst said the ruling should have little or no impact on the company.

The rejection is "not a major indication" of what will happen to the company's sales growth, said David Zimbalist, analyst for Natexis Bleichroder Inc.

The FDA said it sent a "not approvable" letter to Johnson & Johnson (down $0.04 to $67.37, Research), which had applied to expand the use of Risperdal. The drug is currently approved for treatment of a mental chemical balance known as bipolar disorder and brought in $3.1 billion in sales last year, up about 21 percent from a year earlier.

Doug Arbesfeld, spokesman for Janssen Pharmaceutica, the Johnson & Johnson subsidiary that markets Risperdal, said the company would evaluate the FDA's decision, and has not decided on any possible further action.

Johnson & Johnson stock was little changed in morning New York Stock Exchange trading.