MeiraGTx Announces Data at EURETINA 2021 Demonstrating Reversal of Disease Progression Following Treatment With AAV5-RPGR in XLRP

MeiraGTx Holdings announced new data from subjects treated in the phase 1/2 dose escalation phase of Study MGT009 indicating AAV5-RPGR, an investigational gene therapy in development for the treatment of X-linked retinitis pigmentosa (XLRP), reverses course of disease progression when retinal function assessed 12 months following treatment with AAV5-RPGR is compared with retinal function in these same subjects up to 48 months prior to treatment. These data were presented today in an oral session at the EURETINA 2021 Virtual Meeting.

Details of the presentation are listed below.

Title: AAV5-RPGR Gene Therapy for RPGR-Associated X-Linked Retinitis Pigmentosa Reverses Natural Disease Progression

Abstract: 8412

Presenter: Michel Michaelides, BSc MB BS MD(Res) FRCOphth FACS

Date and Time: Thursday, September 9, 8:00am CEST (2:00am ET)

Session: Retinal Dystrophies FP Narration

MeiraGTx and Janssen Pharmaceuticals are jointly developing AAV5-RPGR as part of a broader collaboration to develop and commercialize gene therapies for the treatment of inherited retinal diseases.

EURETINA 2021 Data Summary:

• Ten adult males aged 18-30 years with RPGR-associated XLRP from the natural history study MGT011 were identified as suitable for gene therapy intervention and were subsequently enrolled in the dose escalation phase of MGT009, the phase 1/2 Trial of AAV5-RPGR Gene Therapy
  • Retinal function was assessed through 12 months post-treatment in MGT009
  • Changes in mean retinal sensitivity (MS) and the volumetric analysis of the central 30 degrees of the retinal field (V30), were examined up to 48 months pre-intervention (MGT011) and 12 months post-intervention (MGT009)
• For the intermediate dose escalation cohort (N=4), intervention with AAV5-RPGR therapy in the poorer-seeing eye altered the course of natural disease progression
• At 12 months post-intervention, MS and V30 in the treated eye were similar to levels observed 24 months pre-intervention, while the untreated eye showed a continued downward trajectory

In November 2020, MeiraGTx announced 12-month data from the ongoing phase 1/2 MGT009 clinical trial of AAV5-RPGR, which demonstrated that statistically significant vision improvement was sustained 1 year after treatment in the dose escalation phase of the trial. MeiraGTx and Janssen are preparing to initiate the pivotal phase 3 Lumeos clinical trial of AAV5-RPGR for the treatment of patients with XLRP.