About a decade ago, a novel technology called the Neuro-Spinal Scaffold for patients with spinal cord injury came to fruition. Today, Cambridge, Mass.-based InVivo Therapeutics' INSPIRE study is underway to prove the technology's efficacy.
A bioresorbable polymer scaffold, the Neuro-Spinal Scaffold is designed for implantation at the injury site within a spinal cord contusion, degrading over several weeks. The scaffold is composed of two biocompatible and bioresorbable polymers — Poly(lactic-co-glycolic acid) and Poly-L-Lysine. These polymers are manufactured to create a porous scaffold encouraging cellular attachment and neurite outgrowth.
"What we've learned is, fundamentally what we're doing in the spinal cord is putting in a bandage to lay down in a neuro-permissive environment, which then stimulates endogenous stimulation," explains Mark Perrin, CEO of InVivo.
InVivo quickly recognized the diversity of SCIs and categorized them into two major groups:
- Contusion or closed injuries involve an injured cord, causing the bone to press up against the cord. The cord is not lacerated and the surgeon can view the hemorrhage in the cord through various imaging modalities.
- Compound or open injuries shatter the spine, and bone fragments rip open the cord.
"We were concerned about our product working [for compound injuries] because the outer white matter has been destroyed," Mr. Perrin says. "[However,] we found the surgeons could easily fit the scaffold into the spinal cord defect just as in our experimental hemi-chordectomy model."
Mr. Perrin notes their study has not revealed any predictor variables, and they believe the scaffold could benefit patients with a wide range of injuries.
"I'm so proud of this company. I've never seen passion in employees like this before," says Mr. Perrin. "I can't wait to bring this product to market and help patients — because that's what it's all about."
Making INSPIRE a reality
Back in 2014, InVivo jumpstarted a pilot clinical trial to test this innovative approach for SCI treatment in five patients.
Initially, the FDA mandated a surgeon implant the Neuro-Spinal Scaffold into one patient and wait three months. Based on the submitted safety data, the FDA said the trial could move forward with the second patient. However, Mr. Perrin says the data proved so encouraging after the second implanted patient that the FDA allowed InVivo to run the last three patients concurrently.
In December 2015, the FDA approved the INSPIRE study to test the Neuro-Spinal Scaffold's efficacy and safety for complete thoracic AIS A spinal cord injury. The FDA allowed InVivo to roll over the five patients from the pilot study. InVivo has approval to enroll as many as 30 patients, with the intent of reaching 20 evaluable patients.
The company had enrolled an initial 12 patients, but two died from unrelated complications and two were eliminated due to screening errors. Of the eight implanted patients, the fifth just achieved AIS grade improvement, placing InVivo on track to achieve the INSPIRE study's Objective Performance Criterion. Of the patients achieving complete conversions, two suffered contusion injuries and three suffered compound injuries.
The FDA delivered a surprise in May, however, asking InVivo to consider a control group. Mr. Perrin notes they are continuing to work with the FDA on this issue.
The pathway to commercialization
InVivo had hoped to approach full enrollment for the INSPIRE study by the close of 2016, but because of a pre-specified enrollment hold at 12 patients, the study was on hold at the majority of the company's clinical sites throughout the summer. Mr. Perrin now anticipates reaching full enrollment in the first half of 2017.
"Regardless, [the FDA] is going to want a database of 20 patients for safety purposes," explains Mr. Perrin. "We need six months for all 20 patients, which puts us at the end of 2017 for filing of a humanitarian device exemption application."
Although anticipating submission of a humanitarian device exemption at the end of 2017 or in early 2018, Mr. Perrin notes that aspect of the process is the most unpredictable variable.
If approved, the company will target Level 1 trauma centers. Some SCI patients are sent to Level 2 trauma centers as well, receiving spine stabilization by orthopedic surgeons. InVivo is currently evaluating these centers as secondary commercial focuses.
Although the company plans to push its commercial interests in the United States, Mr. Perrin says they are examining commercializing the product themselves in Europe and Canada.
Headed by a new chief commercial officer, Pamela Stahl, InVivo's commercial strategy will heavily emphasize reimbursement, highlighting the impact of this product on the healthcare system's costs.
In 2015, InVivo teamed up with health economists for a burden-of-illness analysis. The study looked into hospitalization rates for thoracic SCI patients based on level of injury.
"There's such little data on SCI, because there have been no products to impact it," says Mr. Perrin, noting the study revealed "fascinating data" reflecting reduced hospital utilization rates. Mr. Perrin says the study, which will be published in the future, will provide a solid foundation for InVivo's reimbursement strategy.
"That's the basic value proposition we will put forth to payers," explains Mr. Perrin. "Neurosurgeons will be persuaded by the clinical effectiveness and cost effectiveness, and patient advocacy is extraordinary because there's been nothing. Between payers, surgeons and patients, hopefully we will put together the perfect storm."