On Jul. 29, 2021, BOTOX(R) Allergan, an AbbVie company, announced that the U.S. Food and Drug Administration (FDA) had approved a label expansion of BOTOX® to include eight new muscles for the treatment of upper limb spasticity in adults.

The new muscles for treatment include additional muscles of the elbow and forearm (brachialis, brachioradialis, pronator teres, and pronator quadratus), as well as intrinsic hand muscles (lumbricals and interossei) and thumb muscles (flexor pollicis brevis and opponens pollicis). The label included the use of ultrasound as a muscle localization technique in adult spasticity.

Spasticity in adults is commonly caused by stroke, multiple sclerosis, spinal cord injury, cerebral palsy, and traumatic brain injury. Individuals with spasticity experience stiffness in the muscles of their upper and/or lower limbs, and may have difficulty with voluntary control. This can result in difficulty with posture and positioning, and severely interfere with normal muscular movement and function.

BOTOX secured its first FDA approval in 1989 as a treatment for two rare eye muscle disorders, making it the first product of its kind approved in the world.