PALO ALTO, Calif. (AP) _ Syntex Corp. announced plans Wednesday to reorganize its operations in a restructuring that includes an unspecified number of layoffs. The cuts are aimed at remedying weak earnings.

The Palo Alto-based pharmaceutical company said it planned to reorganize its administration and marketing departments while reexamining its research priorities. The company also plans to consolidate some production facilities.

''We are making every effort now to be sure that we will be the right-sized company, focusing on the right priorities in the more challenging years ahead,'' said Paul E. Freiman, chairman and chief executive.

Syntex has 11,500 employees, including 6,400 in the United States.

In August, the company reported disappointing fourth-quarter earnings of $92.5 million.

While Syntex has one of the highest gross profit margins in the drug industry, two of its central products will lose patent protection next year. Naprosyn and Anaprox, both anti-inflammatory drugs, will be forced to compete with generics after December 1993.

In the meantime, Syntex has introduced a new pain reliever, Toradol, that is gobbling marketing expenses but not growing as quickly as hoped.

Company spokeswoman Linda Thomas said no details of the layoffs were announced because no decision had been made about how the cutbacks will be made. She said a decision would likely in the next few months.