Geron (NASDAQ:GERN) ticked 7% higher Monday after announcing the first patient enrollment in its clinical trial of a stem cell-based drug being studied as a treatment for spinal cord injury.

The drug maker has the first US Food and Drug Administration license to use the cells to treat people, and the study is the first publicly known use of the controversial cells in humans.

The drug, GRNOPC1, contains human embryonic stem cell-derived oligodendrocyte progenitor cells that have demonstrated nerve growth stimulating properties that led to the restoration of function in animals with acute spinal cord injury.

Geron's stem cells, the master cells of the body, are taken from human embryos left over from fertility treatments.

“Initiating the GRNOPC1 clinical trial is a milestone for the field of human embryonic stem cell-based therapies,” said Geron CEO Dr. Thomas B. Okarma. “When we started working with hESCs in 1999, many predicted that it would be a number of decades before a cell therapy would be approved for human clinical trials.”

In preclinical trials, the drug showed “significantly improved locomotor activity” in animals with spinal cord injuries when injected seven days after injury, Geron said in a statement.

The objective of the phase I study is to asses the safety and tolerability of GRNOPC1 in patients with American Spinal Injury Association-approved spinal cord injuries.

Patients in the study must be newly injured and receive GRNOPC1 within 14 days.

The first patient was enrolled at Shepherd Center, a 132-bed spinal cord and brain injury rehabilitation hospital in Atlanta, Georgia, the company said.

The site is one of potentially seven in the US that may enroll patients in the trial. Currently, Northwestern Medicine in Chicago is also open for patient enrollment.