Six-month safety follow-up of an adjuvanted SARS-CoV-2 trimeric S-protein subunit vaccine (SCB-2019) in adults: A phase 2/3, double-blind, randomized study.

BACKGROUND: We evaluated the safety of SCB-2019, a protein subunit vaccine candidate containing a recombinant SARS-CoV-2 spike (S) trimer fusion protein, combined with CpG-1018/alum adjuvants. METHODS: This ongoing phase 2/3, double-blind, placebo-controlled, randomized trial is being conducted in Belgium, Brazil, Colombia, the Philippines, and South Africa in participants ≥ 12 years of age. Participants were randomly assigned to receive 2 doses of SCB-2019 or placebo administered intramuscularly 21 days apart. Here, we present the safety results of SCB-2019 over the 6-month period following 2-dose primary vaccination series in all adult participants (≥18 years of age). RESULTS: A total of 30,137 adult participants received at least one dose of study vaccine (n = 15,070) or placebo (n = 15,067) between 24 March 2021 and 01 December 2021. Unsolicited adverse events, medically-attended adverse events, adverse events of special interest, and serious adverse events were reported in similar frequencies in both study arms over the 6-month follow-up period. Vaccine-related SAEs were reported by 4 of 15,070 SCB-2019 recipients (hypersensitivity reactions in two participants, Bell's palsy, and spontaneous abortion) and 2 of 15,067 placebo recipients (COVID-19, pneumonia, and acute respiratory distress syndrome in one participant and spontaneous abortion in the other one). No signs of vaccine-associated enhanced disease were observed. CONCLUSIONS: SCB-2019 administered as a 2-dose series has an acceptable safety profile. No safety concerns were identified during the 6-month follow-up after the primary vaccination. CLINICAL TRIALS REGISTRATION: NCT04672395; EudraCT: 2020-004272-17.

Immunogenicity of an adjuvanted SARS-CoV-2 trimeric S-protein subunit vaccine (SCB-2019) in SARS-CoV-2-naïve and exposed individuals in a phase 2/3, double-blind, randomized study.

BACKGROUND: We evaluated immunogenicity of SCB-2019, a subunit vaccine candidate containing a pre-fusion trimeric form of the SARS-CoV-2 spike (S)-protein adjuvanted with CpG-1018/alum. METHODS: The phase 2/3, double-blind, randomized SPECTRA trial was conducted in five countries in participants aged ≥ 18 years, either SARS-CoV-2-naïve or previously exposed. Participants were randomly assigned to receive two doses of SCB-2019 or placebo administered intramuscularly 21 days apart. In the phase 2 part of the study, on days 1, 22, and 36, neutralizing antibodies were measured by pseudovirus and wild-type virus neutralization assays to SARS-CoV-2 prototype and variants, and ACE2-receptor-binding antibodies and SCB-2019-binding antibodies were measured by ELISA. Cell-mediated immunity was measured by intracellular cytokine staining via flow cytometry. RESULTS: 1601 individuals were enrolled between 24 March and 13 September 2021 and received at least one vaccine dose. Immunogenicity analysis was conducted in a phase 2 subset of 691 participants, including 428 SARS-CoV-2-naïve (381 vaccine and 47 placebo recipients) and 263 SARS-CoV-2-exposed (235 vaccine and 28 placebo recipients). In SARS-CoV-2-naïve participants, GMTs of neutralizing antibodies against prototype virus increased 2 weeks post-second dose (day 36) compared to baseline (224 vs 12.7 IU/mL). Seroconversion rate was 82.5 %. In SARS-CoV-2-exposed participants, one SCB-2019 dose increased GMT of neutralizing antibodies by 48.3-fold (1276.1 IU/mL on day 22) compared to baseline. Seroconversion rate was 92.4 %. Increase was marginal post-second dose. SCB-2019 also showed cross-neutralization capability against nine variants, including Omicron, in SARS-CoV-2-exposed participants at day 36. SCB-2019 stimulated Th1-biased cell-mediated immunity to the S-protein in both naïve and exposed participants. The vaccine was well tolerated, no safety concerns were raised from the study. CONCLUSIONS: A single dose of SCB-2019 was immunogenic in SARS-CoV-2-exposed individuals, whereas two doses were required to induce immune response in SARS-CoV-2-naïve individuals. SCB-2019 elicited a cross-neutralizing response against emergent SARS-CoV-2 variants at antibody levels associated with clinical protection, underlining its potential as a booster. CLINICALTRIALS: gov: NCT04672395; EudraCT: 2020-004272-17.

Effects of Irbesartan Pretreatment on Pancreatic ß-Cell Apoptosis in STZ-Induced Acute Prediabetic Mice.

The current study was performed to investigate the effects and potential effects of irbesartan pretreatment on pancreatic ß-cell apoptosis in a streptozotocin- (STZ-) induced acute mouse model of prediabetes. Twenty-four male BALB/C mice (18-22 g) were randomly divided into three groups: normal control group (NC, n = 6), STZ group (STZ, n = 8), and irbesartan + STZ group (IRB + STZ, n = 10). In the IRB + STZ group, mice were administered irbesartan (300 mg/kg per day) by gavage for one week. The STZ group and IRB + STZ group received STZ (80 mg/kg by intraperitoneal (IP) injection once). The NC group received normal saline (80 mg/kg by IP injection once). Fasting blood glucose prior to STZ injection and presacrifice was analysed using samples withdrawn from the caudal vein to confirm the induction of prediabetes. Haematoxylin and eosin staining, immunohistochemical detection of insulin, and apoptosis analysis were performed. Reverse transcription-quantitative polymerase chain reaction was used to detect angiotensin II type 1 receptor (AT1R), caspase-3, and p38 mitogen-activated protein kinase (MAPK) mRNA expression. Blood glucose was significantly higher in the STZ group (9.01 ± 1.1089 vs 4.78 ± 0.7026) and IRB + STZ group (7.86 ± 1.1811 vs 4.78 ± 0.7026) compared with the NC group (P < 0.05). In comparison to the STZ group, the islet cell damage was marginally improved in the IRB + STZ group, and the IRB + STZ group had a significantly lower apoptotic rate than the STZ group (22.42 ± 8.3675 vs 50.86 ± 5.3395, P < 0.001). AT1R expression in the IRB + STZ group was lower than that in the STZ group (1.56 ± 1.2207 vs 3.92 ± 2.4392, P < 0.05). The mRNA expression of caspase-3 in pancreatic tissue was significantly lower in the IRB + STZ group than in the STZ group (0.90 ± 0.7272 vs 1.88 ± 1.0572, P < 0.05). Similarly, the IRB + STZ group also had lower p38MAPK levels than the STZ group (1.16 ± 1.0642 vs 2.55 ± 1.7925, P > 0.05). In conclusion, irbesartan pretreatment improved glucose levels and insulin secretion and decreased islet ß-cell apoptosis to protect islet ß cells in an STZ-induced acute prediabetic mouse model.

Persistent Macular Thickening After Ranibizumab Treatment for Diabetic Macular Edema With Vision Impairment.

IMPORTANCE: The prevalence of persistent diabetic macular edema (DME) after months of anti-vascular endothelial growth factor therapy and its effect on visual acuity are unknown. OBJECTIVE: To assess subsequent outcomes of eyes with DME persisting for 24 weeks after initiating treatment with 0.5 mg of ranibizumab. DESIGN, SETTING, AND PARTICIPANTS: We performed post hoc, exploratory analyses of a randomized clinical trial from March 20, 2007, through January 29, 2014, from 117 of 296 eyes (39.5%) randomly assigned to receive ranibizumab with persistent DME (central subfield thickness ≥250 µm on time domain optical coherence tomography) through the 24-week visit. INTERVENTIONS: Four monthly intravitreous injections of ranibizumab and then as needed per protocol. MAIN OUTCOMES AND MEASURES: Cumulative 3-year probabilities of chronic persistent DME (failure to achieve a central subfield thickness <250 µm and at least a 10% reduction from the 24-week visit on at least 2 consecutive study visits) determined by life-table analyses, and at least 10 letter (≥2 line) gain or loss of visual acuity among those eyes. RESULTS: The probability of chronic persistent DME among eyes with persistent DME at the 24-week visit decreased from 100% at the 32-week visit to 81.1% (99% CI, 69.6%-88.6%), 55.8% (99% CI, 42.9%-66.9%), and 40.1% (99% CI, 27.4%-52.4%) at the 1-, 2-, and 3-year visits, respectively. At 3 years, visual acuity improved in eyes with and without chronic persistent DME through the follow-up period, respectively, by a mean of 7 letters and 13 letters from baseline. Among 40 eyes with chronic persistent edema through 3 years, 17 (42.5%) (99% CI, 23.1%-63.7%) gained 10 letters or more from baseline, whereas 5 (12.5%) (99% CI, 2.8%-31.5%) lost 10 letters or more from baseline. CONCLUSIONS AND RELEVANCE: These data suggest less than half of eyes treated for DME with intravitreous ranibizumab have persistent central-involved DME through 24 weeks after initiating treatment. Among the 40% that then have chronic persistent central-involved DME through 3 years, longer-term visual acuity outcomes appear to be slightly worse than in the 60% in which DME does not persist. Nevertheless, when following the treatment protocol used in this trial among eyes with vision impairment from DME, long-term improvement in visual acuity from baseline is typical and substantial (≥2-line) loss of visual acuity is likely uncommon through 3 years, even when central-involved DME chronically persists.

Exploratory analysis of the effect of intravitreal ranibizumab or triamcinolone on worsening of diabetic retinopathy in a randomized clinical trial.

IMPORTANCE: The standard care for proliferative diabetic retinopathy (PDR) usually is panretinal photocoagulation, an inherently destructive treatment that can cause iatrogenic vision loss. Therefore, evaluating the effects of therapies for diabetic macular edema on development or worsening of PDR might lead to new therapies for PDR. OBJECTIVE: To evaluate the effects of intravitreal ranibizumab or triamcinolone acetonide, administered to treat diabetic macular edema, on worsening of diabetic retinopathy. DESIGN: Exploratory analysis was performed on worsening of retinopathy, defined as 1 or more of the following: (1) worsening from no PDR to PDR, (2) worsening of 2 or more severity levels on reading center assessment of fundus photographs in eyes without PDR at baseline, (3) having panretinal photocoagulation, (4) experiencing vitreous hemorrhage, or (5) undergoing vitrectomy for the treatment of PDR. SETTING: Community- and university-based ophthalmology practices. PARTICIPANTS: Individuals with central-involved diabetic macular edema causing visual acuity impairment. INTERVENTIONS: Eyes were assigned randomly to sham with prompt focal/grid laser, 0.5 mg of intravitreal ranibizumab with prompt or deferred (≥24 weeks) laser, or 4 mg of intravitreal triamcinolone acetonide with prompt laser. MAIN OUTCOMES AND MEASURES: Three-year cumulative probabilities for retinopathy worsening. RESULTS: For eyes without PDR at baseline, the 3-year cumulative probabilities for retinopathy worsening (P value comparison with sham with prompt laser) were 23% using sham with prompt laser, 18% with ranibizumab with prompt laser (P = .25), 7% with ranibizumab with deferred laser (P = .001), and 37% with triamcinolone with prompt laser (P = .10). For eyes with PDR at baseline, the 3-year cumulative probabilities for retinopathy worsening were 40%, 21% (P = .05), 18% (P = .02), and 12% (P < .001), respectively. CONCLUSIONS AND RELEVANCE Intravitreal ranibizumab appears to be associated with a reduced risk of diabetic retinopathy worsening in eyes with or without PDR. Intravitreal triamcinolone also appears to be associated with a reduced risk of PDR worsening. These findings suggest that use of these drugs to prevent worsening of diabetic retinopathy may be feasible. Given the exploratory nature of these analyses, the risk of endophthalmitis following intravitreal injections, and the fact that intravitreal triamcinolone can cause cataract or glaucoma, use of these treatments to reduce the rates of worsening of retinopathy, with or without PDR, does not seem warranted at this time.

Factors associated with changes in visual acuity and central subfield thickness at 1 year after treatment for diabetic macular edema with ranibizumab.

OBJECTIVE: To identify factors that predict the success or failure of treatment with intravitreal ranibizumab for patients with diabetic macular edema. METHODS: A total of 37 baseline demographic, systemic, ocular, optical coherence tomographic, and fundus photographic variables were assessed for association with change in visual acuity or central subfield thickness between baseline and 1 year in 361 eyes that were randomly assigned to intravitreal ranibizumab with prompt or deferred laser treatment within a trial of ranibizumab, triamcinolone acetonide, and laser treatment for center-involved diabetic macular edema. A categorical variable describing follow-up anatomic responses to therapy was added to the visual acuity outcome model. RESULTS: After adjusting for baseline visual acuity, a larger visual acuity treatment benefit was associated with younger age (P< .001), less severe diabetic retinopathy on clinical examination (P= .003), and absence of surface wrinkling retinopathy (P< .001). The reduction in central subfield thickness during the first treatment year also predicted better visual acuity outcomes (P< .001). After adjusting for baseline central subfield thickness, the presence of hard exudates was associated with more favorable improvement on optical coherence tomographic scan (P= .004). Because only 11 eyes experienced vision loss and 6 eyes experienced an increase in central subfield thickness, factors for poor outcomes could not be evaluated. CONCLUSIONS: A review of baseline factors and anatomic responses during the first year of ranibizumab therapy for association with visual acuity outcome did not identify any features that would preclude ranibizumab treatment. However, baseline central subfield thickness is the strongest predictor of anatomic outcome, and reduction in central subfield thickness during the first treatment year is associated with better visual acuity outcomes.

Intravitreal ranibizumab for diabetic macular edema with prompt versus deferred laser treatment: three-year randomized trial results.

OBJECTIVE: To report the 3-year follow-up results within a previously reported randomized trial evaluating prompt versus deferred (for ≥24 weeks) focal/grid laser treatment in eyes treated with intravitreal 0.5 mg ranibizumab for diabetic macular edema (DME). DESIGN: Multicenter, randomized clinical trial. PARTICIPANTS: Three hundred sixty-one participants with visual acuity of 20/32 to 20/320 (approximate Snellen equivalent) and DME involving the fovea. METHODS: Ranibizumab every 4 weeks until no longer improving (with resumption if worsening) and random assignment to prompt or deferred (≥24 weeks) focal/grid laser treatment. MAIN OUTCOME MEASURES: Best-corrected visual acuity and safety at the 156-week (3-year) visit. RESULTS: The estimated mean change in visual acuity letter score from baseline through the 3-year visit was 2.9 letters more (9.7 vs. 6.8 letters; mean difference, 2.9 letters; 95% confidence interval, 0.4-5.4 letters; P = 0.02) in the deferral group compared with the prompt laser treatment group. In the prompt laser treatment group and deferral group, respectively, the percentage of eyes with a ≥10-letter gain/loss was 42% and 56% (P = 0.02), whereas the respective percentage of eyes with a ≥10-letter gain/loss was 10% and 5% (P = 0.12). Up to the 3-year visit, the median numbers of injections were 12 and 15 in the prompt and deferral groups, respectively (P = 0.007), including 1 and 2 injections, respectively, from the 2-year up to the 3-year visit. At the 3-year visit, the percentages of eyes with central subfield thickness of 250 µm or more on time-domain optical coherence tomography were 36% in both groups (P = 0.90). In the deferral group, 54% did not receive laser treatment during the trial. Systemic adverse events seemed to be similar in the 2 groups. CONCLUSIONS: These 3-year results suggest that focal/grid laser treatment at the initiation of intravitreal ranibizumab is no better, and possibly worse, for vision outcomes than deferring laser treatment for 24 weeks or more in eyes with DME involving the fovea and with vision impairment. Some of the observed differences in visual acuity at 3 years may be related to fewer cumulative ranibizumab injections during follow-up in the prompt laser treatment group. Follow-up through 5 years continues.

Evaluation of visual acuity measurements after autorefraction vs manual refraction in eyes with and without diabetic macular edema.

OBJECTIVE: To compare visual acuity (VA) scores after autorefraction vs manual refraction in eyes of patients with diabetes mellitus and a wide range of VAs. METHODS: The letter score from the Electronic Visual Acuity (EVA) test from the electronic Early Treatment Diabetic Retinopathy Study was measured after autorefraction (AR-EVA score) and after manual refraction (MR-EVA score), which is the research protocol of the Diabetic Retinopathy Clinical Research Network. Testing order was randomized, study participants and VA examiners were masked to refraction source, and a second EVA test using an identical supplemental manual refraction (MR-EVAsuppl score) was performed to determine test-retest variability. RESULTS: In 878 eyes of 456 study participants, the median MR-EVA score was 74 (Snellen equivalent, approximately 20/32). The spherical equivalent was often similar for manual refraction and autorefraction (median difference, 0.00; 5th-95th percentile range, -1.75 to 1.13 diopters). However, on average, the MR-EVA scores were slightly better than the AR-EVA scores, across the entire VA range. Furthermore, the variability between the AR-EVA scores and the MR-EVA scores was substantially greater than the test-retest variability of the MR-EVA scores (P < .001). The variability of differences was highly dependent on the autorefractor model. CONCLUSIONS: Across a wide range of VAs at multiple sites using a variety of autorefractors, VA measurements tend to be worse with autorefraction than manual refraction. Differences between individual autorefractor models were identified. However, even among autorefractor models that compare most favorably with manual refraction, VA variability between autorefraction and manual refraction is higher than the test-retest variability of manual refraction. The results suggest that, with current instruments, autorefraction is not an acceptable substitute for manual refraction for most clinical trials with primary outcomes dependent on best-corrected VA.

Expanded 2-year follow-up of ranibizumab plus prompt or deferred laser or triamcinolone plus prompt laser for diabetic macular edema.

OBJECTIVE: To report expanded 2-year follow-up of a previously reported randomized trial evaluating intravitreal 0.5 mg ranibizumab or 4 mg triamcinolone combined with focal/grid laser compared with focal/grid laser alone for treatment of diabetic macular edema (DME). DESIGN: Multicenter, randomized clinical trial. PARTICIPANTS: A total of 854 study eyes of 691 participants with visual acuity of 20/32 to 20/320 (approximate Snellen equivalent) and DME involving the fovea. METHODS: Continuation of procedures previously reported for the randomized trial. MAIN OUTCOME MEASURES: Best-corrected visual acuity and safety at the 2-year visit. RESULTS: At the 2-year visit, compared with the sham + prompt laser group, the mean change in the visual acuity letter score from baseline was 3.7 letters greater in the ranibizumab + prompt laser group (95% confidence interval adjusted for multiple comparisons [aCI], -0.4 to +7.7), 5.8 letters greater in the ranibizumab + deferred laser group (95% aCI, +1.9 to +9.8), and 1.5 letters worse in the triamcinolone + prompt laser group (95% aCI, -5.5 to +2.4). After the 1- to 2-year visit in the ranibizumab + prompt or deferred laser groups, the median numbers of injections were 2 and 3 (potential maximum of 13), respectively. At the 2-year visit, the percentages of eyes with central subfield thickness ≥250 µm were 59% in the sham + prompt laser group, 43% in the ranibizumab + prompt laser group, 42% in the ranibizumab + deferred laser group, and 52% in the triamcinolone + prompt laser group. No systemic events attributable to study treatment were apparent. Three eyes in 3 (0.8%) of 375 participants had injection-related endophthalmitis in the ranibizumab groups, whereas elevated intraocular pressure and cataract surgery were more frequent in the triamcinolone + prompt laser group. CONCLUSIONS: The expanded 2-year results reported are similar to results published previously and reinforce the conclusions originally reported: Ranibizumab should be considered for patients with DME and characteristics similar to those of the cohort in this clinical trial, including vision impairment with DME involving the center of the macula.

Randomized trial evaluating short-term effects of intravitreal ranibizumab or triamcinolone acetonide on macular edema after focal/grid laser for diabetic macular edema in eyes also receiving panretinal photocoagulation.

PURPOSE: To evaluate 14-week effects of intravitreal ranibizumab or triamcinolone in eyes receiving focal/grid laser for diabetic macular edema and panretinal photocoagulation. METHODS: Three hundred and forty-five eyes with a visual acuity of 20/320 or better, center-involved diabetic macular edema receiving focal/grid laser, and diabetic retinopathy receiving prompt panretinal photocoagulation were randomly assigned to sham (n = 123), 0.5-mg ranibizumab (n = 113) at baseline and 4 weeks, and 4-mg triamcinolone at baseline and sham at 4 weeks (n = 109). Treatment was at investigator discretion from 14 weeks to 56 weeks. RESULTS: Mean changes (±SD) in visual acuity letter score from baseline were significantly better in the ranibizumab (+1 ± 11; P < 0.001) and triamcinolone (+2 ± 11; P < 0.001) groups compared with those in the sham group (-4 ± 14) at the 14-week visit, mirroring retinal thickening results. These differences were not maintained when study participants were followed for 56 weeks for safety outcomes. One eye (0.9%; 95% confidence interval, 0.02%-4.7%) developed endophthalmitis after receiving ranibizumab. Cerebrovascular/cardiovascular events occurred in 4%, 7%, and 3% of the sham, ranibizumab, and triamcinolone groups, respectively. CONCLUSION: The addition of 1 intravitreal triamcinolone injection or 2 intravitreal ranibizumab injections in eyes receiving focal/grid laser for diabetic macular edema and panretinal photocoagulation is associated with better visual acuity and decreased macular edema by 14 weeks. Whether continued long-term intravitreal treatment is beneficial cannot be determined from this study.

Visual acuity testing using autorefraction or pinhole occluder compared with a manual protocol refraction in individuals with diabetes.

PURPOSE: To compare visual acuity (VA) scores obtained after autorefraction or using a pinhole occluder to scores obtained after refraction according to a standard clinical research protocol. DESIGN: Prospective, comparative case series. PARTICIPANTS: One hundred ten study participants (209 eyes) with diabetes mellitus and a broad range of diabetic retinopathy severity and VA. METHODS: We measured VA after autorefraction by a Topcon KR-8000 autorefractor as well as after a Diabetic Retinopathy Clinical Research Network (DRCR.net) protocol manual refraction. The order of testing was randomized and examiners were masked to the source of each refraction. A second VA measurement, utilizing an identical DRCR.net manual refraction, was made in a subset of eyes (n = 144; 69%) to establish test-retest variability for comparison purposes. All eyes underwent VA testing using a pinhole occluder. MAIN OUTCOME MEASURES: Best corrected VA as measured by the Electronic Early Treatment Diabetic Retinopathy Study Visual Acuity Test (E-ETDRS). RESULTS: In all eyes, the median E-ETDRS VA letter score (EVA) obtained after manual refraction (MR-EVA) was 69 (Snellen equivalent 20/40), ranging from 4 to 93 (20/800 to 20/16). The median MR-EVA was slightly better than the median EVA obtained after autorefraction (AR-EVA), with a median difference (AR-EVA - MR-EVA) of -1 letter (25th, 75th percentiles, -4, 2 letters). The absolute difference between AR-EVA and MR-EVA was similar to the test-retest variability of MR-EVA alone. In contrast, MR-EVA was better than EVA obtained using a pinhole occluder (PH-EVA; median PH-EVA - MR-EVA, -4 letters [-9, 0]), and had significantly less test-retest variability (P<0.001). Generally, the spherical equivalent of autorefraction was slightly more hyperopic (or less myopic) than the spherical equivalent of manual refraction (median difference, +0.25 diopters [0, +0.63]). CONCLUSIONS: Given the substantial time and effort required for training and certification of study protocol refractionists, and the similarity between AR-EVA and MR-EVA, further evaluation of autorefraction, but not pinhole occluder testing, as an alternative to the current clinical research gold standard of ETDRS protocol manual refraction in study participants with diabetic retinopathy is warranted.

Factors associated with visual acuity outcomes after vitrectomy for diabetic macular edema: diabetic retinopathy clinical research network.

PURPOSE: To evaluate factors ¶associated with favorable outcomes after vitrectomy for diabetic macular edema. METHODS: Data were collected prospectively on 241 eyes undergoing vitrectomy for diabetic macular edema. Multivariate models were used to evaluate associations of 20 preoperative and intraoperative factors with 6-month outcomes of visual acuity and retinal thickness. RESULTS: Median central subfield thickness decreased from 412 µm to 278 µm at 6 months, but median visual acuity remained unchanged (20/80, Snellen equivalent). Greater visual acuity improvement occurred in eyes with worse baseline acuity (P < 0.001) and in eyes in which an epiretinal membrane was removed (P = 0.006). Greater reduction in central subfield thickness occurred with worse baseline visual acuity (P < 0.001), greater preoperative retinal thickness (P = 0.001), removal of internal limiting membrane (P = 0.003), and optical coherence tomography evidence of vitreoretinal abnormalities (P = 0.006). No associations with clinician's preoperative assessments of the posterior vitreous were identified. CONCLUSION: These results suggest that the removal of epiretinal membranes may favorably affect visual outcome after vitrectomy. Preoperative presence of vitreoretinal abnormalities appeared to be associated with somewhat greater reductions in retinal thickness but not with visual acuity outcome. These results may be useful for future studies evaluating vitrectomy for diabetic macular edema.

Association of fluorescein angiographic features with visual acuity and with optical coherence tomographic and stereoscopic color fundus photographic features of diabetic macular edema in a randomized clinical trial.

BACKGROUND: Fluorescein angiography (FA) has been performed as part of the management of diabetic macular edema for many years. Its current role relative to the role of optical coherence tomography (OCT) is not well defined. PURPOSE: To evaluate the associations of FA features with visual acuity (VA) and with OCT and fundus photographic characteristics in eyes with diabetic macular edema. METHODS: In a clinical trial, conducted by the Diabetic Retinopathy Clinical Research Network to compare two methods of laser photocoagulation to treat diabetic macular edema, FA (film and digital), color photographs, OCT, and VA measurements were obtained at baseline and at 1 year. Grading of morphologic features was performed at a reading center. Reproducibility of FAs was assessed, and the correlations of FA features with VA, OCT, and color photograph features were computed. RESULTS: From 79 clinical sites, data of 323 study eyes and 203 fellow nonstudy eyes were analyzed. Fluorescein leakage area at baseline was associated with reduced VA, increased OCT measures of retinal thickness and volume, and color photographic measurements of retinal thickening (r = 0.33-0.58). No important associations were found with changes from baseline to 12 months in these parameters or with any of the other variables analyzed. CONCLUSION: Fluorescein leakage is associated with VA and some OCT and color photographic variables. We did not identify any unique FA variables that had a stronger association with VA than OCT measures of retinal thickness. These data may be useful to investigators planning future diabetic macular edema clinical trials.

Vitrectomy outcomes in eyes with diabetic macular edema and vitreomacular traction.

PURPOSE: To evaluate vitrectomy for diabetic macular edema (DME) in eyes with at least moderate vision loss and vitreomacular traction. DESIGN: Prospective cohort study. PARTICIPANTS: The primary cohort included 87 eyes with DME and vitreomacular traction based on investigator's evaluation, visual acuity 20/63-20/400, optical coherence tomography (OCT) central subfield >300 microns and no concomitant cataract extraction at the time of vitrectomy. METHODS: Surgery was performed according to the investigator's usual routine. Follow-up visits were performed after 3 months, 6 months (primary end point), and 1 year. MAIN OUTCOME MEASURES: Visual acuity, OCT retinal thickening, and operative complications. RESULTS: At baseline, median visual acuity in the 87 eyes was 20/100 and median OCT thickness was 491 microns. During vitrectomy, additional procedures included epiretinal membrane peeling in 61%, internal limiting membrane peeling in 54%, panretinal photocoagulation in 40%, and injection of corticosteroids at the close of the procedure in 64%. At 6 months, median OCT central subfield thickness decreased by 160 microns, with 43% having central subfield thickness <250 microns and 68% having at least a 50% reduction in thickening. Visual acuity improved by > or =10 letters in 38% (95% confidence interval, 28%-49%) and deteriorated by > or =10 letters in 22% (95% confidence interval, 13%-31%). Postoperative complications through 6 months included vitreous hemorrhage (5 eyes), elevated intraocular pressure requiring treatment (7 eyes), retinal detachment (3 eyes), and endophthalmitis (1 eye). Few changes in results were noted between 6 months and 1 year. CONCLUSIONS: After vitrectomy performed for DME and vitreomacular traction, retinal thickening was reduced in most eyes. Between 28% and 49% of eyes with characteristics similar to those included in this study are likely to have improvement of visual acuity, whereas between 13% and 31% are likely to have worsening. The operative complication rate is low and similar to what has been reported for this procedure. These data provide estimates of surgical outcomes and serve as a reference for future studies that might consider vitrectomy for DME in eyes with at least moderate vision loss and vitreomacular traction.

Effect of focal/grid photocoagulation on visual acuity and retinal thickening in eyes with non-center-involved diabetic macular edema.

PURPOSE: To report visual acuity and anatomic changes from baseline to 12 months after modified Early Treatment Diabetic Retinopathy Study (ETDRS)-style (focal/grid) photocoagulation in eyes with non-center-involved (non-CI) clinically significant macular edema. METHODS: Visual acuity, optical coherence tomography, fluorescein angiography, and fundus photography data were analyzed from eyes with non-CI clinically significant macular edema treated with modified ETDRS-style (focal/grid) photocoagulation in a Diabetic Retinopathy Clinical Research Network trial. RESULTS: Among the 22 eyes (of 22 patients) with 12-month follow-up, median visual acuity letter score remained within 1 letter of baseline over 12 months. The median central subfield retinal thickness decreased by 10 mum, median total macular volume decreased by 0.2 mm, and median fluorescein leakage area within the grid decreased by 0.7 disk areas. CONCLUSION: We are unaware of any other systematic evaluation of eyes with non-CI clinically significant macular edema since the ETDRS. Focal/grid laser in these non-CI eyes was associated with relatively stable visual acuity and retinal thickness measurements, and decreased fluorescein leakage area at 1 year. One-year visual acuity results are consistent with those published by the ETDRS, despite the intervening significant differences in the management of diabetes. Although this was a small study without a concurrent control group, the ETDRS recommendation to consider focal/grid laser in eyes with non-CI clinically significant macular edema still seems appropriate.

Observational study of the development of diabetic macular edema following panretinal (scatter) photocoagulation given in 1 or 4 sittings.

OBJECTIVE: To compare the effects of single-sitting vs 4-sitting panretinal photocoagulation (PRP) on macular edema in subjects with severe nonproliferative or early proliferative diabetic retinopathy with relatively good visual acuity and no or mild center-involved macular edema. METHODS: Subjects were treated with 1 sitting or 4 sittings of PRP in a nonrandomized, prospective, multicentered clinical trial. Main Outcome Measure Central subfield thickness on optical coherence tomography (OCT). RESULTS: Central subfield thickness was slightly greater in the 1-sitting group (n = 84) than in the 4-sitting group (n = 71) at the 3-day (P = .01) and 4-week visits (P = .003). At the 34-week primary outcome visit, the slight differences had reversed, with the thickness being slightly greater in the 4-sitting group than in the 1-sitting group (P = .06). Visual acuity differences paralleled OCT differences. CONCLUSIONS: Our results suggest that clinically meaningful differences are unlikely in OCT thickness or visual acuity following application of PRP in 1 sitting compared with 4 sittings in subjects in this cohort. More definitive results would require a large randomized trial. Application to Clinical Practice These results suggest PRP costs to some patients in terms of travel and lost productivity as well as to eye care providers could be reduced. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00687154.

Association of the extent of diabetic macular edema as assessed by optical coherence tomography with visual acuity and retinal outcome variables.

PURPOSE: To determine whether the extensiveness of diabetic macular edema using a 10-step scale based on optical coherence tomography explains pretreatment variation in visual acuity and predicts change in macular thickness or visual acuity after laser photocoagulation. METHODS: Three hundred twenty-three eyes from a randomized clinical trial of two methods of laser photocoagulation for diabetic macular edema were studied. Baseline number of thickened optical coherence tomography subfields was used to characterize diabetic macular edema on a 10-step scale from 0 to 9. Associations were explored between baseline number of thickened subfields and baseline fundus photographic variables, visual acuity, central subfield mean thickness (CSMT), and total macular volume. Associations were also examined between baseline number of thickened subfields and changes in visual acuity, CSMT, and total macular volume at 3.5 and 12 months after laser photocoagulation. RESULTS: For baseline visual acuity, the number of thickened subfields explained no more variation than did CSMT, age and fluorescein leakage. A greater number of thickened subfields was associated with a greater baseline CSMT, total macular volume, area of retinal thickening, and degree of thickening at the center of the macula (r = 0.64, 0.77, 0.61-0.63, and 0.45, respectively) and with a lower baseline visual acuity (r = 0.38). Baseline number of thickened subfields showed no association with change in visual acuity (r < or = 0.01-0.08) and weak associations with change in CSMT and total macular volume (r from 0.11 to 0.35). CONCLUSION: This optical coherence tomography based assessment of the extensiveness of diabetic macular edema did not explain additional variation in baseline visual acuity above that explained by other known important variables nor predict changes in macular thickness or visual acuity after laser photocoagulation.

Effects of dilation on electronic-ETDRS visual acuity in diabetic patients.

PURPOSE: To evaluate the effect of pupillary dilation on electronic-ETDRS visual acuity (EVA) in diabetic subjects and to assess postdilation EVA as a surrogate for predilation VA. METHODS: DRCR.net-protocol refraction and EVA were measured before and after dilation in diabetic subjects by independent, masked examiners. RESULTS: In 129 eyes of 66 subjects, the median (25th, 75th percentiles) predilation EVA score was 69 (54, 86) (Snellen-equivalent 20/40(-1) [20/80(-1), 20/20(+1)]). Predilation VA was >or=20/20, <20/20 to 20/40, <20/40 to 20/80, and <20/80 in 29%, 19%, 26%, and 26% of eyes, respectively. Median EVA change postdilation was -3 letters (-7, 0). The absolute change in EVA score was >or=15 letters (>or=3 ETDRS lines) in 9% of eyes and >or=10 letters (>or=2 ETDRS lines) in 19% of eyes. Extent of change (range +12 to -25 letters) was associated with baseline VA. No relationship was identified between EVA change and gender, race, lens status, refractive error, DR severity, or primary cause of vision loss. CONCLUSIONS: In an optimized clinical trial setting, there is a decline in best corrected EVA after dilation in diabetic subjects. The large range and magnitude of VA change preclude using postdilation EVA as a surrogate for undilated VA.

A randomized trial comparing intravitreal triamcinolone and focal/grid photocoagulation for diabetic macular edema: baseline features.

PURPOSE: To compare baseline demographic, systemic, and ocular characteristics within age and racial subgroups among participants in this Diabetic Retinopathy Clinical Research Network clinical trial and to compare this cohort with other cohorts enrolled in phase 3 clinical trials for diabetic retinopathy. METHODS: Thirty-six month, randomized, controlled, multicenter clinical trial of 693 participants with diabetic macular edema enrolled at 88 clinical sites in the United States. Participants were categorized into self-reported race/ethnicity subgroups and into one of three age groups: 18 to <60, 60 to <70, and 70 and older. RESULTS: Mean age of participants was 63 years, 72% were white, and median visual acuity letter score was 62 (approximately 20/63). No substantial difference was identified between racial subgroups for any baseline variable. Older participants were more likely to have Type 2 diabetes mellitus and longer duration disease. The most frequent levels of diabetic retinopathy among 840 study eyes were moderate (level 43) to moderately severe (level 47) nonproliferative disease. CONCLUSION: While the racial composition of this cohort does not differ from other cohorts in large phase 3 trials that have evaluated participants with diabetic retinopathy, the inclusion of many subjects over age 70 and a better level of glycemic control are distinguishing features.

Optical coherence tomography measurements and analysis methods in optical coherence tomography studies of diabetic macular edema.

OBJECTIVE: To evaluate optical coherence tomography (OCT) measurements and methods of analysis of OCT data in studies of diabetic macular edema (DME). DESIGN: Associations of pairs of OCT variables and results of 3 analysis methods using data from 2 studies of DME. PARTICIPANTS: Two hundred sixty-three subjects from a study of modified Early Treatment of Diabetic Retinopathy Study (mETDRS) versus modified macular grid (MMG) photocoagulation for DME and 96 subjects from a study of diurnal variation of DME. METHODS: Correlations were calculated for pairs of OCT variables at baseline and for changes in the variables over time. Distribution of OCT measurement changes, predictive factors for OCT measurement changes, and treatment group outcomes were compared when 3 measures of change in macular thickness were analyzed: absolute change in retinal thickness, relative change in retinal thickness, and relative change in retinal thickening. MAIN OUTCOME MEASURES: Concordance of results using different OCT variables and analysis methods. RESULTS: Center point thickness correlated highly with central subfield mean thickness (CSMT) at baseline (0.98-0.99). The distributions of changes in CSMT were approximately normally distributed for absolute change in retinal thickness and relative change in retinal thickness, but not for relative change in retinal thickening. Macular thinning in the mETDRS group was significantly greater than in the MMG group when absolute change in retinal thickness was used, but not when relative change in thickness and relative change in thickening were used. Relative change in macular thickening provides unstable data in eyes with mild degrees of baseline thickening, unlike the situation with absolute or relative change in retinal thickness. CONCLUSIONS: Central subfield mean thickness is the preferred OCT measurement for the central macula because of its higher reproducibility and correlation with other measurements of the central macula. Total macular volume may be preferred when the central macula is less important. Absolute change in retinal thickness is the preferred analysis method in studies involving eyes with mild macular thickening. Relative change in thickening may be preferable when retinal thickening is more severe.