Syncona portfolio company Spur provides update on FLT201 and planned Phase III clinical trial

Syncona Ltd, a leading life science investor focused on creating, building and scaling global leaders in life science, notes that its portfolio company Spur Therapeutics (“Spur”) has completed enrolment in the Phase I/II GALILEO-1 clinical trial of FLT201, its adeno-associated virus (AAV) gene therapy candidate for Gaucher disease. Based on the encouraging data from this Phase I/II trial, Spur has selected a single infusion of FLT201 at a low dose of 4.5e11 vg/kg for its Phase III trial expected to start in CY2025.

Six patients have been dosed in the GALILEO-1 trial and were treated with a single infusion of FLT201 at a dose of 4.5e11 vg/kg. Two of the six patients have completed the full nine months of follow-up. The others have been followed for between 16 and 38 weeks after dosing. One patient was identified to have pre-existing neutralising antibodies to the AAV3 capsid used to deliver FLT201, below the protocol cut-off. This patient has been excluded from the efficacy analysis. All six patients are included in the safety analysis, with FLT201 continuing to demonstrate a favourable safety and tolerability profile.

Efficacy data as of 30 June 2024 data cut-off:

• Lyso-Gb1, an established biomarker of clinical response in Gaucher disease, was substantially reduced in the four patients with persistently high lyso-Gb1 levels, despite years of treatment with currently approved therapies.
• One patient entered the trial with well-controlled lyso-Gb1, and these levels have been maintained.
• Maintenance of normal levels, or improvement to normal levels, of haemoglobin and platelets seen in five patients, which are well-accepted regulatory endpoints for Gaucher disease.
• Improvement seen in bone marrow burden in five patients, which shows FLT201 is reaching deeper tissues that are poorly addressed by currently approved therapies.
• Clinically relevant improvement in patient-reported pain and fatigue, leading to improved function, in the one patient who entered the trial with debilitating chronic pain and fatigue.
• Two patients developed antibodies to GCase, the enzyme that is deficient in people with Gaucher disease, but still experienced benefits from treatment with FLT201.
• Improvements seen in lyso-Gb1 and bone marrow burden from baseline, as well as maintenance of haemoglobin and platelets in normal ranges.
• In the patient with longest exposure (greater than three months beyond detection of antibodies), the antibodies appear to have been transient and improvements in clinical parameters continue to be observed.

Spur expects to report additional data from the Phase I/II GALILEO-1 trial in the second half of 2024.

Chris Hollowood, CEO of Syncona Investment Management Limited and Chair of Spur, said: “We continue to be highly encouraged by the data coming from the FLT201 programme in Gaucher disease. The safety and tolerability of the treatment, alongside these compelling efficacy signals, suggest FLT201 has the potential to play an important role in the treatment of patients with Gaucher disease. Spur is expecting to report further data on FLT201 in the second half of the year, and we look forward to working with the team as they move towards initiating a Phase III trial in CY2025.”

Spur’s announcement is copied below and can be accessed on the company’s website at https://spurtherapeutics.com/.