GREENWOOD VILLAGE, Colo., July 9, 2012 /PRNewswire/ -- Ampio Pharmaceuticals, Inc. (Nasdaq: AMPE), a biopharmaceutical company developing innovative proprietary drugs for inflammation, eye disease, kidney disease, CNS disease, metabolic disease and male sexual dysfunction and conducting clinical trials on its three lead drugs (Ampion™ , Optina™ & Zertane™), announced the significant results from their further analysis of its Optina™ trial on DME .
The Optina™ trial, conducted at St Michael Hospital in Canada, was a phase II, placebo-controlled, double-masked study to evaluate the efficacy and safety of a 12-week treatment with oral Optina™ in adult patients with Diabetic Macular Edema (DME). Three Optina™ doses were studied and administered orally twice daily. Patients were randomized into one of the three Optina™ arms, or placebo. The primary endpoint was change from baseline to week twelve of treatment in retinal thickness as measured by Optical Coherence Tomography (OCT). Secondary endpoints were 1) change from baseline to week twelve in retinal volume and 2) change from baseline to week twelve in Early Treatment Diabetic Retinopathy Study (ETDRS) Best Corrected Visual Acuity (BCVA).
Statistical methodology:An alpha of 0.20 was selected a priori for all analyses and any p value of less than 0.2 is considered statistically significant. The study was powered to find differences at this type I error rate. Change in retinal thickness was analyzed using a repeated measures analysis of covariance. A backwards stepwise model was built, using an exit value of p > 0.05. Dunnett's method was used to adjust for multiple comparisons and Satterthwaite's degree of freedom estimation method was used. Data analysis:
- In addition to the clear interaction of dose of Optina™ with BMI (reported previously i.e. for the higher BMI the higher of the low doses was more effective (p=0.01) and for the lower BMI the lower of the low doses was more effective (p=0.12)), analysis of the data revealed that for the optimal dose, 6 out of 7 patients had significant reductions in center subfield retinal thickness (ranging from 42um to 383um or 13-60% reductions). There was a correlation between the reduction in the subfield central retinal thickness and improvement in visual acuity. By way of example: in a patient with a reduction of 383um (baseline was 641um) visual acuity improved by four lines after 12 weeks of treatment (+20 BCVA). This trend was observed in all 6 patients who had a reduction in subfield central retinal thickness.
- The effect of treatment on retinal volume depended on baseline hemoglobin A1c (HA1c) levels (p=0.03). For high and moderate baseline values of HA1c, the optimal low dose of Optina™ showed significantly higher reductions in retinal volume compared to placebo (p=0.005). The very low Optina™ dose significantly lowered retinal volume at the lowest values of HA1c, compared to placebo (p=0.17).
- The effects observed at week 4 were not different than those at week 12, which is in agreement with the in vitro results demonstrating a rapid effect of Optina™ on vascular permeability.
- Both low doses of Optina™ saw decreases in retinal volume. The optimal low dose saw a statistically significant decrease in retinal volume compared to placebo, p=0.05.
- Defined a priori, and supported in the literature, a decrease in retinal thickness exceeding 11% was considered clinically significant.(1,2) In the subgroup of patients whose retinal thickness decreased by more than 11%, the inverse linear relationship between change from baseline BCVA and percent change in baseline retinal thickness was statistically significant, (r2=0.52, p=0.01).
- Nearly all subjects [86% (6/7)] receiving the optimal low dose of Optina™ saw a clinically relevant change in retinal thickness after twelve weeks, compared to 29% (2/7) subjects in the placebo group (almost 3 fold improvement over placebo).
- Using the ICD-9-CM Categories for visual acuity defined as: severe vision loss (BCVA score: 35-54); moderate vision loss (BCVA score: 55-74); and mild vision loss (BCVA score: 75-94), eight (36%) subjects improved at least one category. The placebo group had the lowest proportion of subjects with improvement at 14%, whereas 47% (7/15) of subjects treated with Optina™ improved at least one category (3.3 fold over placebo).
- The Diabetic Retinopathy Clinical Research Network. A Phase 2 randomized clinical trial or intravitreal bevacizumab for diabetic macular edema. Ophthalmology 2007;114:1860-67.
- The Diabetic Retinopathy Clinical Research Network. Reproducibility of Macular Thickness and Volume Using Zeiss Optical Coherence Tomography in Patients with Diabetic Macular Edema. Ophthalmology. 2007 August; 114(8): 1520–1525.
- The Mayo Clinic. Type 2 Diabetes, Complications. http://www.mayoclinic.com/health/type-2-diabetes/DS00585/DSECTION=complications.