Emily Y. Chew
NEW ORLEANS — An implant with ciliary neurotrophic factor has a beneficial effect and reduces the progressive loss of photoreceptors compared with untreated eyes, Emily Y. Chew, MD, said at Retina Subspecialty Day preceding the American Academy of Ophthalmology meeting, where she discussed results of the phase 2 trial of ciliary neurotrophic factor for macular telangiectasia.
Macular telangiectasia is a neurodegenerative problem, Chew said, and neurotrophic factors have been shown in animal models to slow the loss of photoreceptor cell death.
“We’ve had an animal model that is ‘MacTel-like’ that looks like it has responded very well to CNTF, so for these reasons we study CNTF for macular telangiectasia,” she said.
In the prospective, multicenter, single-masked, sham-controlled study, 99 eyes of 67 participants were randomly assigned to either device or sham arms, with the device group being surgically implanted with genetically modified retinal pigment epithelium cells transfected with human ciliary neurotrophic factor (CNTF).
Primary outcome was change from baseline in the ellipsoid zone as measured by en face spectral domain OCT at 24 months. Secondary outcomes included changes in retinal sensitivity, visual acuity and reading speed.
“We wanted the functional changes to support the changes we might see,” Chew said.
The sham group had 31% greater progression of neurodegeneration as measured by area of ellipsoid zone loss than the treated eyes. There was no difference in mean best corrected visual acuity from baseline between the two groups, and no participant lost more than 15 letters.
In patients given CNTF, reading speed stabilized, whereas reading speed continued to deteriorate in those in the sham group.
“There was good correlation between the structural and functional changes,” Chew said. – by Patricia Nale, ELS
Chew EY. Phase 2 trial of ciliary neurotrophic factor for macular telangiectasia. Presented at AAO Subspecialty Days; Nov. 10-11, 2017; New Orleans.
Disclosure: Chew reports no relevant financial disclosures.