QLT Inc. (Nasdaq:QLTI) (TSX:QLT) ("QLT" or the "Company") today announced expansion of the Phase 1b clinical proof-of-concept study of QLT091001 in the treatment of Leber Congenital Amaurosis (LCA) to include patients with Retinitis Pigmentosa (RP), a set of hereditary retinal diseases demonstrating clinical features similar to LCA. Both diseases result from genetic mutations of either retinal pigment epithelium protein 65 (RPE65) or lecithin:retinol acyltransferase (LRAT) that are amenable to intervention with QLT091001. QLT091001 is an orally administered synthetic retinoid replacement for 11-cis-retinal, which is a key biochemical component of visual function.
LCA is a debilitating, inherited, progressive retinal degenerative disease that leads to retinal dysfunction and significant visual impairment beginning at birth. RP is characterized by degeneration of rod and cone photoreceptors, resulting in a more variable loss of vision in late childhood to adulthood. There are at least 300,000 patients with RP worldwide, of which less than 5% carry the inherited deficiencies of either RPE65 or LRAT.
"We are very excited to be expanding the potential uses for QLT091001 into another rare indication, Retinitis Pigmentosa," said Bob Butchofsky, President and Chief Executive Officer of QLT. "We continue to enroll LCA patients in the trial, with a total of 7 patients currently treated or under treatment. We expect to treat the first RP patient in the coming weeks."
The Phase 1b trial is an open-label, single-center, multinational study to evaluate the safety profile and early dosimetry effects of QLT091001 on retinal function. Up to a total of 24 patients diagnosed with LCA (6 LRAT mutations, 6 RPE65 mutations) or RP (6 LRAT mutations, 6 RPE65 mutations) will be enrolled. Subjects will receive daily oral regimens of 2 different doses of QLT091001 for 7 days at the Montreal Children's Hospital at the McGill University Health Centre, Montreal, Canada under the supervision of the trial's principal investigator, Robert K. Koenekoop, M.D., Ph.D. Patients are rigorously monitored to ensure safety and tolerability. Efficacy assessments included several indices of visual function including best-corrected ETDRS visual acuity, electroretinogram, and visual field testing.
In April, the Company announced that after 7 days of treatment with QLT091001, the first three patients treated experienced clinically relevant improvements in one or more visual function parameters. The onset of visual changes was rapid and there was progressive improvement beyond the 7 days of treatment, with some effects persisting for up to 4 months after treatment was completed.
Source QLT Inc.