Novel heterozygous PRPH2 variant identified in a patient with spinocerebellar ataxia type 14 and macular dystrophy.

PURPOSE: To report on a patient with spinocerebellar ataxia type 14 (SCA14) and macular dystrophy with identification of a novel PRPH2 variant. METHODS: Case report. RESULTS: A 63-year-old female with molecularly confirmed SCA14 presented with symmetric pigmentary disturbances in a perifoveal distribution resembling a pattern macular dystrophy. She had no history of using medications with recognized toxic macular effects. Subsequent genetic testing confirmed a novel heterozygous missense variant of unknown significance in PRPH2 (PRPH2: c.694 G>A, p.(Ala232Thr)). CONCLUSIONS: To our knowledge, this is the first case of macular dystrophy identified in a patient with SCA14. While it is possible that the macular dystrophy observed in this patient might be an under-reported phenotype associated with SCA14, the pattern of macular changes is consistent with PRPH2-related disorders. The identified missense variant is predicted to be damaging by most in silico models, and the residue is highly conserved, adding support to a dual genetic diagnosis in this case.

Gene therapy for cross-correction of somatic organs and the CNS in mucopolysaccharidosis II in rodents and non-human primates.

Mucopolysaccharidosis II (MPS II) is a rare lysosomal storage disease characterized by deficient activity of iduronate-2-sulfatase (I2S), leading to pathological accumulation of glycosaminoglycans (GAGs) in tissues. We used iduronate-2-sulfatase knockout (Ids KO) mice to investigate if liver-directed recombinant adeno-associated virus vectors (rAAV8-LSP-hIDSco) encoding human I2S (hI2S) could cross-correct I2S deficiency in Ids KO mouse tissues, and we then assessed the translation of mouse data to non-human primates (NHPs). Treated mice showed sustained hepatic hI2S production, accompanied by normalized GAG levels in somatic tissues (including critical tissues such as heart and lung), indicating systemic cross-correction from liver-secreted hI2S. Brain GAG levels in Ids KO mice were lowered but not normalized; higher doses were required to see improvements in brain histology and neurobehavioral testing. rAAV8-LSP-hIDSco administration in NHPs resulted in sustained hepatic hI2S production and therapeutic hI2S levels in cross-corrected somatic tissues but no hI2S exposure in the central nervous system, perhaps owing to lower levels of liver transduction in NHPs than in mice. Overall, we demonstrate the ability of rAAV8-LSP-hIDSco to cross-correct I2S deficiency in mouse somatic tissues and highlight the importance of showing translatability of gene therapy data from rodents to NHPs, which is critical for supporting translation to clinical development.

Effect of Macular Internal Limiting Membrane Peeling on Single Surgery Success Rates of Vitrectomy for Uncomplicated, Primary Macula-Off Retinal Detachment.

Purpose: To determine the anatomic and visual outcomes of pars plana vitrectomy for uncomplicated, primary macula-off rhegmatogenous retinal detachment (RRD) with and without internal limiting membrane (ILM) peeling. Methods: This retrospective chart review comprised 129 patients with uncomplicated, primary macula-off RRD presenting between January 1, 2016, and May 31, 2021. Thirty-six patients (27.9%) had ILM peeling and 93 (72.0%) did not. The primary outcome was the rate of recurrent RRD. Secondary outcomes included preoperative and postoperative best-corrected visual acuity (BCVA), epiretinal membrane (ERM) formation, and macular thickness. Results: No significant difference was found in the risk for recurrent RRD between patients who had ILM peeling and those who did not (2.8% [1/36] and 5.4% [5/93], respectively) (P = 1.00). The final postoperative BCVA was better in eyes that did not have ILM peeling (P< .001). No ERM occurred in the group with ILM peeling, whereas ERM occurred in 27 patients (29.0%) who did not have ILM peeling. The temporal macular retina was thinner in eyes in which ILM peeling was performed. Conclusions: The risk for recurrent RRD was not statistically lower in eyes having ILM peeling of the macula in uncomplicated, primary macula-off RRD. Despite a reduction in postoperative ERM formation, eyes having macular ILM peeling had worse postoperative VA.

TOPICAL DORZOLAMIDE-TIMOLOL WITH INTRAVITREOUS ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR FOR RETINAL VEIN OCCLUSION: A PILOT STUDY.

PURPOSE: To evaluate topical dorzolamide hydrochloride-timolol maleate as an adjunct therapy to intravitreous anti-vascular endothelial growth factor injections in eyes with retinal vein occlusion resistant to treatment. METHODS: Retinal vein occlusion patients with a history of persistent macular edema, despite fixed-interval intravitreous anti-vascular endothelial growth factor injections, were enrolled between April 4, 2016, and June 4, 2017. On enrollment, patients were instructed to administer one drop of topical dorzolamide-timolol twice daily for the duration of the study. They were maintained on the same anti-vascular endothelial growth factor drug and same interval between injections as preenrollment for the subsequent two visits. Primary outcome measures were change in central foveal thickness, central subfield thickness, and thickest macular cut at the final study visit. RESULTS: Eight patients (8 eyes) were eligible for enrollment and completed the study. There was a significant decrease in central foveal thickness (P = 0.02), central subfield thickness (P = 0.03), and thickest macular cut (P = 0.01) between the enrollment visit and the final visit. There was a decrease in mean (±SD) logarithm of the minimal angle of resolution from 0.52 (±0.35) (20/66, Snellen equivalent) at the enrollment visit to 0.41 (±0.35) (20/51, Snellen equivalent) at the final visit (P = 0.08). CONCLUSION: Topical dorzolamide-timolol may have a beneficial anatomical and functional effect in eyes with macular edema secondary to retinal vein occlusion resistant to treatment.

Scleral-Sutured Intraocular Lens Dislocations Secondary to Eyelet Fractures.

OBJECTIVE: To report clinical features and visual outcomes following eyelet fractures of scleral-sutured enVista MX60 (Bausch + Lomb) intraocular lenses (IOL). DESIGN: Retrospective, multi-center, multi-surgeon, observational case series. METHODS: Study Population: Patients with scleral-sutured enVista MX60 IOLs that experienced either an intraoperative or post-operative eyelet fracture associated with dislocation or subluxation. PROCEDURES: All records were reviewed for patients with a dislocated or subluxed scleral-sutured enVista MX60 IOL. Clinical features and outcomes were gathered. Main Outcome Measures: Clinical setting, surgical technique, complications, and visual acuity. RESULTS: A total of 25 scleral-sutured enVista MX60 IOLs displacements secondary to eyelet fractures in 23 eyes of 23 patients were included. There were 20 IOLs that sustained a postoperative fracture and 5 IOLs that sustained an intraoperative fracture. Of the postoperative fractures, 7 were dislocated and 13 were subluxed. Gore-Tex was the suture of choice for 19 of the postoperative fractures and all 5 of the intraoperative fractures, and Prolene was used for 1 postoperative fracture. The mean time until postoperative fracture was 96 ± 125 days, and the median time was 61 (IQR 48-144) days. Of the postoperative fractures, new MX60s were sutured in 10 patients, and 2 of them experienced repeat displacements due to a new eyelet fracture. In the intraoperative fracture group, new MX60s were sutured in 4 patients and an Akreos AO60 lens was placed in the 5th patient. The mean preoperative best-corrected logMAR visual acuity for all patients improved from 1.2 ± 0.8 (20/317 Snellen equivalent) to 0.5 ± 0.5 (20/63 Snellen equivalent) at most recent follow-up after lens replacement. CONCLUSIONS: Scleral-sutured MX60 intraocular lenses can experience intraoperative or postoperative eyelet fractures, resulting in lens subluxation or dislocation. Surgeons should be aware of this complication when evaluating secondary intraocular lens options.

PHACOVITRECTOMY FOR PRIMARY RHEGMATOGENOUS RETINAL DETACHMENT REPAIR: A Retrospective Review.

PURPOSE: To analyze the single surgery success rate and anterior segment complications related to phacoemulsification and intraocular lens implantation in a series of patients undergoing phacovitrectomy for all types of primary rhegmatogenous retinal detachment. METHODS: We performed a retrospective interventional case series on 302 eyes undergoing phacovitrectomy for primary rhegmatogenous retinal detachment repair between November 1, 2016, and February 2, 2019, in Edmonton, Canada. Primary outcomes included single surgery retinal reattachment rate and anterior segment complications. Secondary outcomes included the effects of proliferative vitreoretinopathy and macula and/or peripheral internal limiting membrane peeling on the rate of surgical success. RESULTS: The single surgery success rate of phacovitrectomy for all types of primary rhegmatogenous retinal detachment was 85.1%. The presence of proliferative vitreoretinopathy was associated with lower surgical success (odds ratio, 0.33; P = 0.01). Macular internal limiting membrane peeling was associated with higher surgical success (odds ratio, 2.4; P = 0.05). Anterior segment complications included posterior capsular opacification (28.8%), posterior synechiae (10.9%), and posterior capsular rupture (2.3%). CONCLUSION: Phacovitrectomy is a safe and effective treatment option for the primary repair of rhegmatogenous retinal detachments. This study provides evidence to support the safe incorporation of phacoemulsification and intraocular lens implantation with retinal surgery.

Leveraging Quantitative Systems Pharmacology Approach into Development of Human Recombinant Follistatin Fusion Protein for Duchenne Muscular Dystrophy.

Quantitative understanding about the dynamics of drug-target interactions in biological systems is essential, especially in rare disease programs with small patient populations. Follistatin, by antagonism of myostatin and activin, which are negative regulators of skeletal muscle and inflammatory response, is a promising therapeutic target for Duchenne Muscular Dystrophy. In this study, we constructed a quantitative systems pharmacology model for FS-EEE-Fc, a follistatin recombinant protein to investigate its efficacy from dual target binding, and, subsequently, to project its human efficacious dose. Based on model simulations, with an assumed efficacy threshold of 7-10% muscle volume increase, 3-5 mg/kg weekly dosing of FS-EEE-Fc is predicted to achieve meaningful clinical outcome. In conclusion, the study demonstrated an application of mechanism driven approach at early stage of a rare disease drug development to support lead compound optimization, enable human dose, pharmacokinetics, and efficacy predictions.

Comparison of Residual Subfoveal Fluid by Intraoperative OCT After Macula-Involving RRD Repair Using Direct Drainage, Drainage Retinotomy, or Perfluoro-n-Octane.

BACKGROUND AND OBJECTIVE: This study evaluated the residual subfoveal fluid (SFF) immediately after rhegmatogenous retinal detachment (RRD) repair using intraoperative optical coherence tomography (iOCT). PATIENTS AND METHODS: This retrospective cohort study assessed fovea-involving RRD repaired by pars plana vitrectomy (PPV) using different drainage techniques. iOCT images were acquired through the fovea at the start of the case prior to initiating vitrectomy and then again immediately prior to introduction of tamponade. RESULTS: Ten eyes (32.3%) received perfluoro-n-octane (PFO), 12 (38.7%) underwent a posterior drainage retinotomy, and nine (29.0%) had drainage through the retinal break. There was no significant difference in the mean SFF thickness between eyes in either group (P = .85). There was no significant association between SFF thickness on iOCT and functional or anatomic outcomes (P > .05). CONCLUSION: There is no difference in the amount of residual SFF as measured on iOCT during RRD repair with pars plana vitrectomy using either direct drainage, drainage retinotomy, or PFO. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:497-503.].

Are the changes in diagnostic criteria for gestational diabetes mellitus reflected in perinatal outcomes? A retrospective assessment.

BACKGROUND: Gestational diabetes mellitus (GDM) is glucose intolerance first diagnosed during pregnancy not due to overt diabetes. Recent changes to the diagnostic guidelines have been shown to increase the apparent occurrence of GDM. AIM: The aim of this study was to compare retrospectively the neonatal outcomes between groups defined using the new and old criteria to assess the impact of guideline changes on pregnancy outcomes. METHODS: The study was of singleton babies delivered of 641 women, who had oral glucose tolerance testing and pregnancy care at a single tertiary centre between 2011 and 2015. RESULTS: Compared to the population of women not now considered to have GDM by International Association of Diabetes and Pregnancy Study Groups criteria (two-hour glucose concentration ≤8.4 mmol/L), neonates born to women with the new lower fasting criterion (5.1-5.4 mmol/L) and/or the new 60-min group (glucose ≥10 mmol/L) combined were significantly more likely to have birthweight ≥90th percentile (22% vs 5%, P < 0.0001). In contradistinction, there was a significant excess number of small-for-dates babies (birthweight ≤10th percentile) in all subgroups previously diagnosed and treated for GDM by the Australian Diabetes in Pregnancy Society criteria (17% vs 7%, P = 0.001). Rates for lower uterine segment caesarean section, admission to the neonatal intensive care unit / special care nursery and Apgar scores at one and five minutes were not statistically different across all groups. CONCLUSIONS: Outcomes support the lowering of the fasting criterion to extend management of GDM to limit growth of large birthweight neonates. An unexpected outcome was that in women previously treated for GDM, there were increased numbers of low-birthweight neonates.

A CASE OF INTRAVESICAL BACILLUS CALMETTE-GUERIN-RELATED ENDOPHTHALMITIS AND RETINITIS CONFIRMED WITH RETINAL BIOPSY.

PURPOSE: To present a rare case of bilateral endogenous chorioretinitis and unilateral endophthalmitis due to Mycobacterium bovis in a patient who received intravesical bacillus Calmette-Guerin (BCG) treatment. METHODS: We present a case of a single male patient with bilateral endogenous chorioretinitis due to Mycobacterium bovis in a patient who received intravesical BCG, an attenuated strain of M. bovis widely used to treat superficial bladder cancer. The patient underwent intravitreal tap, vitrectomy, and chorioretinal biopsy with histologic examination. RESULTS: The patient presented with a visual acuity of light perception in the right eye and 20/25 in the left eye. Examination of the right eye revealed dense vitreous haze, whereas the left eye demonstrated multifocal, yellow, round subretinal pigment epithelial lesions in the macula. The patient underwent a vitreous tap with injection of antibiotics and was admitted to the hospital for empiric systemic antibacterial and antifungal treatment along with an endogenous endophthalmitis workup. His systemic evaluation and vitreous tap did not identify a causal organism, and the eyes failed to improve on empiric therapies. He underwent pars plana vitrectomy and retinal biopsy of the right eye that revealed vitreal and infiltrative retinal acid-fast bacilli. Cultures confirmed M. bovis to be susceptible to ethambutol, rifampin, and isoniazid. After starting antimycobacterials, his vision improved to finger counting in the right eye, and his vision and appearance of the lesions remained stable in the left eye at postoperative month one. CONCLUSION: Intravesical BCG stimulates a local cell-mediated response that destroys malignant cells. It is generally well tolerated, although it rarely can result in secondary systemic infection. Intravesical BCG-related endophthalmitis is rare and should be considered in the setting of ocular inflammation in patients with a history of bladder cancer who may not disclose previous treatment with BCG.

Myostatin and activin blockade by engineered follistatin results in hypertrophy and improves dystrophic pathology in mdx mouse more than myostatin blockade alone.

BACKGROUND: Myostatin antagonists are being developed as therapies for Duchenne muscular dystrophy due to their strong hypertrophic effects on skeletal muscle. Engineered follistatin has the potential to combine the hypertrophy of myostatin antagonism with the anti-inflammatory and anti-fibrotic effects of activin A antagonism. METHODS: Engineered follistatin was administered to C57BL/6 mice for 4 weeks, and muscle mass and myofiber size was measured. In the mdx model, engineered follistatin was dosed for 12 weeks in two studies comparing to an Fc fusion of the activin IIB receptor or an anti-myostatin antibody. Functional measurements of grip strength and tetanic force were combined with tissue analysis for markers of necrosis, inflammation, and fibrosis to evaluate improvement in dystrophic pathology. RESULTS: In wild-type and mdx mice, dose-dependent increases in muscle mass and quadriceps myofiber size were observed for engineered follistatin. In mdx, increases in grip strength and tetanic force were combined with improvements in muscle markers for necrosis, inflammation, and fibrosis. Improvements in dystrophic pathology were greater for engineered follistatin than the anti-myostatin antibody. CONCLUSIONS: Engineered follistatin generated hypertrophy and anti-fibrotic effects in the mdx model.

Protein Engineering on Human Recombinant Follistatin: Enhancing Pharmacokinetic Characteristics for Therapeutic Application.

Follistatin (FS) is an important regulatory protein, a natural antagonist for transforming growth factor-ß family members activin and myostatin. The diverse biologic roles of the activin and myostatin signaling pathways make FS a promising therapeutic target for treating human diseases exhibiting inflammation, fibrosis, and muscle disorders, such as Duchenne muscular dystrophy. However, rapid heparin-mediated hepatic clearance of FS limits its therapeutic potential. We targeted the heparin-binding loop of FS for site-directed mutagenesis to improve clearance parameters. By generating a series of FS variants with one, two, or three negative amino acid substitutions, we demonstrated a direct and proportional relationship between the degree of heparin-binding affinity in vitro and the exposure in vivo. The triple mutation K(76,81,82)E abolished heparin-binding affinity, resulting in ∼20-fold improved in vivo exposure. This triple mutant retains full functional activity and an antibody-like pharmacokinetic profile, and shows a superior developability profile in physical stability and cell productivity compared with FS variants, which substitute the entire heparin-binding loop with alternative sequences. Our surgical approach to mutagenesis should also reduce the immunogenicity risk. To further lower this risk, we introduced a novel glycosylation site into the heparin-binding loop. This hyperglycosylated variant showed a 10-fold improved exposure and decreased clearance in mice compared with an IgG1 Fc fusion protein containing the native FS sequence. Collectively, our data highlight the importance of improving pharmacokinetic properties by manipulating heparin-binding affinity and glycosylation content and provide a valuable guideline to design desirable therapeutic FS molecules.

Patient Comfort with Yellow (577 nm) vs. Green (532 nm) Laser Panretinal Photocoagulation for Proliferative Diabetic Retinopathy.

PURPOSE: Pain associated with panretinal photocoagulation (PRP) can adversely affect the number and quality of retinal burns delivered and subsequently increase the number of treatment sessions required to achieve regression of proliferative diabetic retinopathy (PDR). We assessed comfort in patients undergoing treatment with yellow (577 nm) vs. green (532 nm) PRP for PDR. DESIGN: Prospective, single-center, randomized crossover clinical trial. SUBJECTS: Patients with PDR with high-risk characteristics. METHODS: Subjects were equally randomized to first receive PRP with a laser indirect ophthalmoscope with either green (IQ 532; IRIDEX, Mountain View, CA) or yellow (IQ 577; IRIDEX) laser, followed by additional treatment with the opposite laser using standardized settings in the superior hemisphere of a single treatment eye per patient. Topical anesthetic was used in all study eyes before each treatment and power was titrated until moderate grey-white retinal burns were achieved. MAIN OUTCOME MEASURES: The primary outcome measure was patient's perceived pain as measured with a standardized 10-point pain scale. Secondary outcome measures included laser power, treatment time, number of treatment shots with each laser, and physician ease-of-use score with each laser on a 10-point scale. RESULTS: Forty patients (40 eyes) with a mean age of 54.0 years were enrolled. Mean pain scores were similar when comparing treatment with yellow and green laser (3.1 ± 2.3 vs. 2.8 ± 2.6; P = 0.40). No significant difference was seen in visual acuity (P = 0.44) or central macular thickness (P = 0.39) 1 month after PRP. Additionally, there were no significant differences when comparing minimum power required (243.2 ± 74.2 vs. 234.0 ± 59.6 mW; P = 0.55), treatment time (5.1 ± 3.6 vs. 5.6 ± 3.9 minutes; P = 0.384), and number of treatment shots (257.6 ± 12.6 vs. 258.0 ± 2.3; P = 0.68). Six of 7 co-investigators (85%) preferred using yellow laser over green and reported ease-of-use scores of 9.0 ± 1.2 and 7.6 ± 1.4, respectively (P = 0.07). No severe adverse events occurred. CONCLUSIONS: Patient comfort during PRP for PDR utilizing laser indirect ophthalmoscopy is similar for green and yellow wavelengths.

ETX2514 is a broad-spectrum ß-lactamase inhibitor for the treatment of drug-resistant Gram-negative bacteria including Acinetobacter baumannii.

Multidrug-resistant (MDR) bacterial infections are a serious threat to public health. Among the most alarming resistance trends is the rapid rise in the number and diversity of ß-lactamases, enzymes that inactivate ß-lactams, a class of antibiotics that has been a therapeutic mainstay for decades. Although several new ß-lactamase inhibitors have been approved or are in clinical trials, their spectra of activity do not address MDR pathogens such as Acinetobacter baumannii. This report describes the rational design and characterization of expanded-spectrum serine ß-lactamase inhibitors that potently inhibit clinically relevant class A, C and D ß-lactamases and penicillin-binding proteins, resulting in intrinsic antibacterial activity against Enterobacteriaceae and restoration of ß-lactam activity in a broad range of MDR Gram-negative pathogens. One of the most promising combinations is sulbactam-ETX2514, whose potent antibacterial activity, in vivo efficacy against MDR A. baumannii infections and promising preclinical safety demonstrate its potential to address this significant unmet medical need.