Acorda will receive a royalty from Watson based on product sales.
Additional terms of the agreement have not been disclosed.
Tizanidine hydrochloride capsule is a short-acting drug indicated for the management of spasticity.
Because of the short duration of effect, treatment with tizanidine hydrochloride capsules should be reserved for those daily activities and times when relief of spasticity is most important, Acorda said.