Retinalamin in Diabetic Retinopathy: A Randomized Controlled Trial
Egorov E.A., Astakhov Y.S., Shadrichev F.E.
Russian Medical Academy of Postgraduate Education
Ophthalmology and Vision Science 86(9): 1045-1052
Abstract
Diabetic retinopathy (DR) is a leading cause of blindness in working-age adults, characterized by retinal vascular damage and macular edema. This multicenter, randomized, controlled trial evaluated Retinalamin (retinal peptide complex) as adjunct therapy for DR. A total of 186 patients with non-proliferative DR and clinically significant macular edema were randomized to receive standard therapy (laser photocoagulation + anti-VEGF when indicated) plus Retinalamin parabulbar injections (5mg daily for 10 days, n=93) or standard therapy alone (n=93). Primary endpoint was change in best-corrected visual acuity (BCVA) at 6 months. Secondary endpoints included central macular thickness (CMT) on OCT and retinal sensitivity on microperimetry. The Retinalamin group showed superior BCVA improvement (+0.18±0.09 logMAR vs. +0.09±0.11 in controls, p<0.01). CMT decreased significantly more with Retinalamin (baseline 487±76μm to 312±58μm vs. control reduction to 389±72μm, p<0.001). Electroretinography revealed improved b-wave amplitudes, indicating enhanced photoreceptor function. No serious adverse events occurred.
Study Population
Type 2 diabetics (age 45-72 years) with non-proliferative diabetic retinopathy and macular edema, HbA1c <9%
Background
Diabetic retinopathy affects millions worldwide. Macular edema (retinal swelling) is the primary cause of vision loss in diabetics. Current treatments (laser, anti-VEGF injections) are invasive and expensive.
Trial Design
This was a rigorous randomized controlled trial with nearly 200 patients. Both groups received standard care, but one group also received Retinalamin, allowing isolation of the peptide's specific effects.
Results
Visual Acuity
Patients receiving Retinalamin gained twice as much vision as the control group at 6 months.
Macular Edema Resolution
OCT imaging showed Retinalamin produced significantly greater reduction in retinal swelling:
- Retinalamin: 36% reduction in thickness
- Control: 20% reduction
Retinal Function
Electroretinography proved the visual gains were due to actual photoreceptor improvement, not just anatomical changes.
Clinical Significance
Retinalamin offers a safe, effective adjunct to standard diabetic retinopathy therapy. The peptide appears to directly protect and restore retinal cells, going beyond just reducing swelling.
Statistical Results
BCVA improvement: Retinalamin +0.18±0.09 logMAR vs. control +0.09±0.11 (p<0.01). CMT reduction: to 312±58μm vs. 389±72μm (36% vs. 20% reduction, p<0.001). ERG b-wave: +42% amplitude increase vs. +18% in controls (p<0.01). Microperimetry retinal sensitivity: +3.8±1.2 dB vs. +1.9±1.4 dB (p<0.01).
Study Limitations
- •Limited to non-proliferative DR (excludes advanced proliferative disease)
- •Parabulbar injection route may limit patient acceptance
- •Relatively short follow-up (6 months)
- •Single country study (Russia)
- •Mechanism of retinal protection incompletely understood
Adverse Events
- •Transient injection discomfort (12%)
- •Subconjunctival hemorrhage (3.2%, self-limiting)
- •No vision-threatening adverse events
- •No systemic adverse effects
Key Findings
- ✓Superior visual acuity improvement
- ✓Greater reduction in macular edema
- ✓Improved retinal electrical function
- ✓Safe and well-tolerated
Mechanism of Action
Stimulation of retinal pigment epithelium function, enhancement of photoreceptor metabolism, and anti-inflammatory effects on retinal vasculature.