Sam Shepard, the Pulitzer Prize-winning playwright and Oscar-nominated actor, died on Thursday. He was 73.

Chris Boneau, a spokesperson for Shepard's family, tells CNN he died of complications of ALS, more commonly known as Lou Gehrig's disease.

Shepard authored more than 40 plays, winning the Pulitzer Prize for drama in 1979 for his play "Buried Child," which explored the breakdown of the traditional American family. The Broadway production of the drama was nominated for five Tony Awards in 1996.

Shepard received an Oscar nomination for best supporting actor in 1993 for his portrayal of pilot Chuck Yeager in the astronaut drama "The Right Stuff."

Shepard is survived by two children and his sisters.

"The family requests privacy at this difficult time," Boneau said in a statement to CNN.