Sio Gene Therapies comes to the end of its rocky road

Sio Gene Therapies' litany of clinical disappointments over the last few years has finally led to the demise of the biotech, formerly known as Axovant and one of the 'vant' companies originally founded by entrepreneur Vivek Ramaswamy.

Sio's board of directors has decided it is time to call it quits and abandon the business, after efforts launched earlier this year to try to find a new change in direction for the business came to nothing.

"After evaluating the company's strategic options, the board of directors unanimously concluded that it is in the best interests of the shareholders to dissolve and liquidate the company," said chief executive David Nassif.

It will now hold a shareholder meeting in the first quarter of 2023 to get approval for the wind-down of its activities, convert assets to cash, and distribute the proceeds to its investors.

The Switzerland-based business was set up in 2014 as a neuroscience specialist, developing drugs for indications like Alzheimer's disease, Lewy Body dementia, and rapid eye movement (REM) sleep behaviour disorder.

Its flagship project was intepirdine, an experimental 5-HT6 receptor antagonist it acquired from GSK, but that failed to show efficacy in a phase 3 trial reported in 2018 and the programme was scrapped.

Axovant turned its attention to another neuroscience drug – 5-HT2A receptor inverse agonist nelotanserin, licensed from Arena Pharma – but that failed a phase 2 study in REM sleep behaviour disorder shortly thereafter.

The biotech reacted to the setbacks with a pivot towards gene therapies, buying rights to a lentiviral-based gene therapy for Parkinson's disease from Oxford BioMedica, codenamed AXO-Lenti-PD, and followed with two other licensing deals involving a pair of gene therapies for GM1 and GM2 gangliosidosis – AXO-AAV-GM1 and AXO-AAV-GM2 – from the University of Massachusetts.

It also rebranded to Sio, but the new business fared no better in its new incarnation. AXO-Lenti-PD failed a phase 2 trial and was dropped from development earlier this year, prompting the departure of former CEO Pavan Cheruvu.

Just four months later the company also discontinued the gangliosidosis programmes and announced big layoffs and the start of a its strategic review.

Nassif said the board had devoted "substantial time and effort in identifying and pursuing opportunities to enhance shareholder value," but that process "did not yield a potential transaction […] viewed as reasonably likely to provide greater realisable value to its shareholders than the complete dissolution and liquidation of the company."