Medication may be able to sharply alter the course of cerebral palsy, scientists said Wednesday, after finding that animals with the developmental condition responded remarkably to a new treatment.

Within five days of being given an anti-inflammatory drug, researchers found that newborn rabbits with cerebral palsy made dramatic progress. The animals were able to walk and hop, tasks they’d had great difficulty with prior to the treatment.

The findings, reported in the journal Science Translational Medicine, offer tremendous promise for people with the developmental disability, researchers said.

“This suggests that there is a window of opportunity to prevent cerebral palsy,” said Roberto Romero, chief of the Perinatology Research Branch of the National Institutes of Health and an author of the study.

For the study, researchers replicated in rabbits the brain inflammation often seen in people with cerebral palsy. They then used tiny molecules known as dendrimers to deliver an anti-inflammatory drug called N-acetyl-L-cysteine, or NAC, directly to the affected part of the brain.

The rabbits that received this treatment showed marked progress as compared to those who received saline or NAC alone without the targeted drug delivery, though benefits were seen in both groups that received medication.

“This is an exciting breakthrough and it certainly points toward new hope for those affected by cerebral palsy,” said Rangaramanujam Kannan, a chemical engineer at Wayne State University who worked on the study. “More questions need to be answered, but the potential is immense.”

Rabbits in the study were treated on their first day of life, so further research is needed to assess whether or not the benefits of the drug therapy may be seen in humans and how effective it might be when used beyond infancy, the researchers said.

In addition to cerebral palsy, researchers are also exploring the benefits of NAC for people with autism and Alzheimer’s disease.