Biopharmaceutical company StemCells Inc (NASDAQ STEM) said Wednesday it transplanted a human neural stem cell as part of an early stage clinical trial to combat a rare neurodegenerative disorder.

The disorder, called Batten Disease, affects infants and young children and is brought on by inherited genetic mutations. That mutation causes the lack of a lysosomal enzyme, which leads to loss of motor skills, seizures and other symptoms. Eventually, the patient becomes blind, bedridden and unable to communicate, the company said.

The disease is fatal.

The company's human neural stem cell is transplanted into the brain of the patient, with the goal of producing the missing enzyme. The intention is for the enzyme to increase and continuing increasing over time, providing long-term delivery.

The Phase I clinical trial is designed to primarily study the safety of the treatment, but will also look at effectiveness. In all, six patients are expected to undergo the treatment over the next 12 months.

The beginning of human studies for the treatment gave biotech company StemCells a boost in premarket trading, raising shares 36 cents, or 11.3 percent, to $3.53 on the INET electronic exchange.