Emitbio Inc., a life science company developing light-based therapies, is seeking emergency use authorization (EUA) from the U.S. FDA for its investigational device to treat mild to moderate COVID-19 infection at home.

The portable, hand-held device is designed to be used by patients with mild to moderate symptoms of COVID-19, and works by directing precise wavelengths of visible light to the back of the throat and surrounding tissues. The device is not yet available for sale in the U.S.

The application to the FDA is based on promising results from an early-phase randomized clinical trial of the device in 31 adults who tested positive for SARS-CoV-2 and had mild to moderate symptoms, as well as a phase I safety study in healthy volunteers. In the randomized trial, the device reduced the SARS-CoV-2 viral load and sped up the time to symptom resolution.

“We think that this trial definitively shows that you can reduce viral load and accelerate symptom resolution in mild to moderate patients. That’s where we’ve focused our EUA,” Emitbio’s chief science officer Nate Stasko, told BioWorld.

If the EUA is granted by the FDA, it would be a potentially large market opportunity for Emitbio. The company estimates that about half of U.S. adults who are diagnosed with COVID-19 are not high risk and are not hospitalized.

Clinical trial results

The phase I/II clinical trial results are slated to be submitted for peer review and have not yet been published in the scientific literature, Stasko explained. However, the company released top-line results showing promising efficacy for the investigational device.

The placebo-controlled, randomized, double-blind study was aimed at determining product safety and a treatment difference between the treatment device and a placebo device. The study protocol called for a four-day, twice-daily dosing regimen with either the investigational device, which emits electromagnetic energy, or a placebo device that is inactive but produces the same user experience. Patients place the device in the mouth and each treatment duration is about five minutes.

To be included, patients had to be 18-65 years of age, have a positive test for SARS-CoV-2 by nasal swab, and be no more than three days from the onset of signs and symptoms of COVID-19. Patients were excluded if they had a body mass index of 36 or higher, and if they had severe symptoms indicating acute respiratory distress or more serious outcomes, such as difficulty breathing or persistent pain or pressure in the chest.

Among the 20 adults who used the treatment device, they experienced a 99.9% mean reduction in SARS-CoV-2 viral load in saliva between the baseline visit on day 1 and day 8. There was virtually no change from baseline for the 11 adults using the placebo device, based on comparison of arithmetic means, according to results released by Emitbio.

The trial also showed an improvement in the median time to patient-reported signs and symptoms among patients who used the treatment device. The median time to sustained clearance of COVID-19-related symptoms was 104 hours in the treated patients vs. 161 hours in the patients who received placebo. This translates to a median acceleration of symptom resolution of 57 hours, or just over two days (P < 0.05).

“If you could be symptom-free two days sooner and viral load-free two days sooner, that’s two days more of work, that’s two days more of school, that’s two days more of back-to-normal living and being COVID free. So, we think two days is definitely clinically meaningful,” Stasko said.

Even as the world moves forward with vaccination against COVID-19, Stasko said there is a key role for treatment of patients who develop mild to moderate COVID-19. “For those people who have yet to be vaccinated, for those who choose not to be vaccinated, or those in whom it proves ineffective, because that is a risk as well, we want to be the therapeutic backstop,” he said.

The Durham, N.C.-based company is planning additional studies to investigate the efficacy of the device in other patient populations, such as higher-risk hospitalized patients with COVID-19.

“There are a number of other patient populations still with COVID who are in need of therapy, and so we’re looking at people at higher risk who are hospitalized who may benefit from adding this to their course of therapy as well,” he said.

Emitbio, which is an operating subsidiary of Know Bio LLC, also recently announced evidence from laboratory testing showing that the company’s light technology is active against the Middle East Respiratory Syndrome coronavirus (MERS-CoV). In laboratory experiments, precise wavelengths of light achieved a greater than 99.9% reduction in the MERS-CoV viral load. These laboratory results suggest that the company’s light technology could also be effective against emerging SARS-CoV-2 variants, according to Emitbio.