The approval is conditional solely upon a minor change to the informed consent form that has already been submitted to the FDA. Full approval of the amendment is expected in the next 30 days.

With this transition, the study will be known formally as "The INSPIRE Study: InVivo Study of Probable Benefit of the Neuro-Spinal Scaffold for Safety and Neurologic Recovery in Subjects with Complete Thoracic AIS A Spinal Cord Injury."

The INSPIRE Study is designed to enroll 20 implanted patients, inclusive of the five patients already enrolled. The primary endpoint is defined as the proportion of patients achieving an improvement of at least one ASIA Impairment Scale (AIS) grade at 6 months post-implantation.

The INSPIRE study is conditionally approved to enroll up to 12 patients, but InVivo expects that the FDA will approve the full 20 patients following the review of 6-month safety data for the first five patients. The company plans to submit these data in the second quarter of 2016.

An objective performance criterion (OPC) for the study to support probable benefit using historical benchmarks is under discussion with the FDA. In large European and US databases, the published rates of spontaneous improvement of at least one AIS grade in complete (AIS A), thoracic SCI patients at 6 months are less than 16%. An additional study protocol amendment may be required to establish the OPC.

The inclusion criteria have also been broadened to include patients with T2 injuries (new range T2-T12/L1) and ages 16-17 (new range 16-70). The FDA has also agreed to increase the total number of allowable U.S. sites to 40. In addition to the U.S. sites, the company plans to initiate the study in Canada and the United Kingdom with the intent to include patients enrolled at ex-U.S. sites as part of the 20 patient study.

"This conditional approval marks one of the most significant corporate milestones the company has achieved to date. Being able to convert our pilot study into a small pivotal probable benefit study provides us with a very efficient path to commercialization," said Mark Perrin, Chief Executive Officer and Chairman. "We anticipate completing enrollment in the pivotal probable benefit study and submitting an application for Humanitarian Device Exemption (HDE) approval in 2017."

The company will continue to announce the enrollment of each patient and any conversions of AIS classification as well as any other dramatically positive or negative events.

The company will also seek to communicate interim results at various scientific and medical meetings. The company does not consider a patient’s unchanged AIS classification or a medically insignificant adverse event to be material.