Simulations Plus Inc. has sold 50 additional licenses for its GastroPlus software to the Food and Drug Administration, the company announced Friday.

The Lancaster company, which makes computer programs that simulate the metabolic effects of drugs, had earlier sold 20 licenses for GastroPlus to the FDA. The licenses are used by various divisions of the agency, including the Office of Generic Drugs, Center for Veterinary Medicine, Office of Clinical Pharmacology, and the National Center for Toxicological Research.

The monetary value of the licenses was not disclosed.

“One of the reasons for an order for additional licenses of this magnitude is to meet the needs of other FDA divisions to review an increasing number of regulatory submissions referencing GastroPlus modeling,” John DiBella, vice president of marketing and sales for Simulations Plus, said in a statement. “Scientists at the FDA want to understand how they can encourage more use of the software program to address questions related to complex drug product behaviors.”

Shares closed up 18 cents or 2.3 percent to $8.12 on the Nasdaq.