Nanoscope Therapeutics Inc. announced topline data from its phase 2b clinical trial assessing its lead product MCO-010 for vision restoration in patients diagnosed with advanced retinitis pigmentosa (RP).
Tell me about MCO-010.
MCO-010 is an ambient-light activatable multi-characteristic opsin (MCO) optogenetic received as a single intravitreal injection to potentially restore vision with enhanced contrast and definition in real-world environments.
In essence, the gene therapy reprograms healthy retina cells to make them photosensitive by using proprietary adeno-associated virus (AAV2) vector and promoter technology to deliver the MCO genes into retina bipolar cells, enabling vision in different color environments.
What else should I know?
The therapy is currently the only broadband, fast, and most-light sensitive opsin in clinical trials; it has also already received both Orphan Drug and Fast Track designations from the FDA in 2022.
Now talk about this trial.
The randomized, double-masked, sham-controlled, multicenter phase 2b RESTORE trial (NCT04945772) enrolled 27 patients (ages 18+) with severe vision impairment due to RP; 18 participants received one injection of MCO-010 (1.2E11gc/eye or 0.9E11gc/eye), while 9 participants received one sham injection.
Primary outcome measures included mean change in multi-luminance y-mobility test (MLYMT, vision-guided mobility) score vs sham; other key efficacy assessments were multi-luminance shape discrimination test (MLSDT, near-object recognition) and best-corrected visual acuity (BCVA).
Note: A 0.3 LogMAR change for BCVA would be considered clinically meaningful (negative change means improved visual acuity [VA]).
What did they find?
Twelve-month data found improvements in vision function following MCO-010 treatment to have a favorable safety profile, similar with previous clinical findings.
Other key outcomes included:
- 18% of MCO-010-treated patients demonstrated a 2 or more luminance level improvement in MLYMT or MLSDT compared to 44.4% in placebo patients.
- 12 out 18 MCO-010-treated patients improved by 2 or more luminance levels in MLYMT vs 3 out of 9 placebo patients.
- 10 out of 18 MCO-010-treated patients improved by 2 or more luminance levels in the MLSDT vs just 2 out of 9 in placebo patients.
- 7 out of 18 MCO-010-treat patients improved by -0.3 LogMAR or more in BCVA compared to 1 of 9 in placebo patients.
Anything else?
The primary outcome difference compared to placebo was +1.0 (95% confidence interval; 0.0, 3.0).
Overall, the results were consistent with that of a previous phase 1/2 trial (NCT04919473) on MCO-010.
Any adverse events?
MCO-010 was found to be well-tolerated; there were no reports of serious or severe ocular or systemic adverse events (SAEs); just one SAE was reported in a placebo patient.
Across both groups, treatment emergent adverse events (TAEs) were comparable, with the most common ocular TAEs including anterior chamber cells, ocular hypertension, and conjunctival hemorrhage.
Significance?
Pending continued positive data on MC0-010, the therapy has the potential to become the first treatment approved for patients with vision loss due to RP.