Tonix Pharmaceuticals has announced its intention to develop the investigational candidate TNX-102 for the potential treatment of long COVID syndrome – also known as Post-Acute Sequelae of COVID-19 (PASC).
Currently, TNX-102 SL (cyclobenzaprine HCl sublingual tablets) is in mid-phase 3 development as a daily bedtime treatment for fibromyalgia.
In a statement, Tonix said that long COVID syndrome symptoms – including pain, sleep disturbance, fatigue and brain fog – overlap with fibromyalgia, another long-term condition characterised by widespread musculoskeletal pain.
Individuals who develop long COVID syndrome typically experience symptoms long after recovery from acute COVID-19 infection, with most patients who have been studied appearing to have cleared the SARS-CoV-2 virus from their systems.
The syndrome can last for months and ranges in severity – from mild to severe or ‘incapacitating’. Although long COVID syndrome is typically associated with moderate or severe COVID-19, it can occur after mild COVID-19 or after asymptomatic SARS-CoV-2 infection.
“We are excited to begin development of TNX-102 SL for the treatment of Long COVID because the programme leverages what we have learned about the pharmacodynamic activity of TNX-102 SL from more than one thousand participants who have been or are enrolled in our fibromyalgia trials to date,” said Seth Lederman, president and chief executive officer of Tonix.
“Long COVID has been compared to fibromyalgia because of the common symptoms of sleep disturbance, persistent pain, fatigue, and brain fog,” he added.
Tonix is expecting interim data from the phase 3 RALLY study of TNX-102 in fibromyalgia in the third quarter of 2021 and topline data in the first quarter of 2022.
The drug candidate is also being evaluated as a treatment for post-traumatic stress disorder (PTSD), alcohol use disorder and agitation in Alzheimer’s disease.
According to Tonix’s chief medical officer Gregory Sullivan, TNX-102 has already “showed activity in addressing pain, sleep disturbance and fatigue in [the] fibromyalgia phase 3 study”.
“In our double-blind clinical studies for both fibromyalgia and post-traumatic stress disorder (PTSD), TNX-102 SL showed robust activity in improving sleep quality starting within the first two weeks of treatment,” he added.