Shares of Auxilium Pharmaceuticals Inc. slipped Monday after the company reported data from a new study of its drug Xiaflex.

Xiaflex is approved as a treatment for Dupuytren’s contracture, a condition that causes the tendons of the hand to thicken and shorten, making the fingers curve inward. The drug is approved for patients who have one “cord” of thickened tissue in their hands, and Auxilium is now testing the drug in patients who have more than one cord.

There were 60 patients in the study. Auxilium said about 60 percent of the patients’ joints experienced significant improvement after one injection of Xiaflex into each contracted joint. Auxilium said those rates were “numerically higher” than the results of patients who were treated with a placebo in other studies. The results couldn’t be evaluated for statistical significance because they came from separate clinical trials.

Shares of Auxilium lost 79 cents, or 3 percent, to $25.91 in afternoon trading.

The Malvern, Pa., company plans to start a larger trial in the third quarter. The Food and Drug Administration originally approved Xiaflex in early 2010. Auxilium is also planning to ask the FDA to approve the drug as a treatment for Peyronie’s disease, a condition in which scar tissue causes severe curvature of the penis, making sex difficult. It says it will file for that approval before the end of 2012.

In the trial, the most common side effects were bruising, pain and swelling at the injection site. Auxilium reported two other serious side effects. It said one patient was hospitalized for 24 hours for pain after two injections into the patient’s little finger. Another patient suffered a middle finger ligament injury. Auxilium said both of those side effects have been observed in other studies.