Browsing by Subject "Intravitreal injection"

Now showing 1 - 3 of 3
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    Long-Acting Microparticle Formulation of Griseofulvin for Ocular Neovascularization Therapy
    (Wiley, 2024) Chobisa, Dhawal; Muniyandi, Anbukkarasi; Sishtla, Kamakshi; Corson, Timothy W.; Yeo, Yoon; Pharmacology and Toxicology, School of Medicine
    Neovascular age-related macular degeneration (nAMD) is a leading cause of vision loss in older adults. nAMD is treated with biologics targeting vascular endothelial growth factor; however, many patients do not respond to the current therapy. Here, a small molecule drug, griseofulvin (GRF), is used due to its inhibitory effect on ferrochelatase, an enzyme important for choroidal neovascularization (CNV). For local and sustained delivery to the eyes, GRF is encapsulated in microparticles based on poly(lactide-co-glycolide) (PLGA), a biodegradable polymer with a track record in long-acting formulations. The GRF-loaded PLGA microparticles (GRF MPs) are designed for intravitreal application, considering constraints in size, drug loading content, and drug release kinetics. Magnesium hydroxide is co-encapsulated to enable sustained GRF release over >30 days in phosphate-buffered saline with Tween 80. Incubated in cell culture medium over 30 days, the GRF MPs and the released drug show antiangiogenic effects in retinal endothelial cells. A single intravitreal injection of MPs containing 0.18 µg GRF releases the drug over 6 weeks in vivo to inhibit the progression of laser-induced CNV in mice with no abnormality in the fundus and retina. Intravitreally administered GRF MPs prove effective in preventing CNV, providing proof-of-concept toward a novel, cost-effective nAMD therapy.
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    Phase 1 Study of THR-687, a Novel, Highly Potent Integrin Antagonist for the Treatment of Diabetic Macular Edema
    (Elsevier, 2021-07-14) Khanani, Arshad M.; Patel, Sunil S.; Gonzalez, Victor H.; Moon, Suk J.; Jaffe, Glenn J.; Wells, John A.; Kozma, Petra; Dugel, Pravin U.; Maturi, Raj K.; Ophthalmology, School of Medicine
    Purpose: To evaluate the safety and preliminary efficacy of THR-687 in patients with center-involved diabetic macular edema (DME). Design: Phase 1, open-label, multicenter, 3 + 3 dose-escalation study with 3-month follow-up. Participants: Patients 18 years of age or older with visual impairment resulting from DME. Methods: Single intravitreal injection of THR-687 (0.4 mg, 1.0 mg, or 2.5 mg). Main outcome measures: The primary outcome measure was the incidence of dose-limiting toxicities (DLTs). The secondary outcome measure was the incidence of adverse events (AEs), including the occurrence of laboratory abnormalities. Exploratory outcome measures included changes from baseline in best-corrected visual acuity (BCVA) and central subfield thickness (CST), assessments of ischemia and leakage on fluorescein angiography, and THR-687 levels in plasma. Results: Twelve patients were treated: 3 patients received 0.4 mg of THR-687, 3 patients received 1.0 mg of THR-687, and 6 patients received 2.5 mg of THR-687. Most patients were men (9/12 patients). Their mean age was 57.8 years. No DLTs or serious AEs were reported at any of the dose levels tested. Overall, 9 AEs in the study eye were reported for 5 of 12 patients. Of those, 4 AEs in 3 of 12 patients were deemed treatment related by the investigator, all of which were mild, started on the day of the injection, and had resolved within 28 days without treatment. Overall, mean gains from baseline in BCVA were observed at all study visits with a rapid onset (7.2 Early Treatment Diabetic Retinopathy Study [ETDRS] letters at day 7) and a durability up to the end of the study (8.3 ETDRS letters at month 3). A mean decrease in CST was observed up to month 1. Overall, the mean BCVA gains and CST decreases were highest at the highest THR-687 dose level tested. THR-687 was undetectable in plasma at 7 days after the injection. Conclusions: At all dose levels tested, a single intravitreal injection of THR-687 was safe and well tolerated. Preliminary efficacy was observed by a rapid gain in BCVA with 3 months' durability and a decrease in CST up to 1 month after the injection.
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    Two-Year Results of the Phase 3 Randomized Controlled Study of Abicipar in Neovascular Age-Related Macular Degeneration
    (Elsevier, 2021) Khurana, Rahul N.; Kunimoto, Derek; Yoon, Young Hee; Wykoff, Charles C.; Chang, Andrew; Maturi, Raj K.; Agostini, Hansjürgen; Souied, Eric; Chow, David R.; Lotery, Andrew J.; Ohji, Masahito; Bandello, Francesco; Belfort, Rubens, Jr.; Li, Xiao-Yan; Jiao, Jenny; Le, Grace; Kim, Kimmie; Schmidt, Werner; Hashad, Yehia; CEDAR and SEQUOIA Study Groups; Ophthalmology, School of Medicine
    Purpose: To report the 2-year efficacy and safety of abicipar every 8 weeks and quarterly (after initial doses) compared with monthly ranibizumab in patients with treatment-naïve neovascular age-related macular degeneration (nAMD). Design: Two multicenter, randomized, phase 3 clinical trials with identical protocols (CEDAR and SEQUOIA). Analyses used pooled trial data. Participants: The trials enrolled 1888 patients (1 eye/patient) with active choroidal neovascularization secondary to age-related macular degeneration and best-corrected visual acuity (BCVA) of 24 to 73 Early Treatment Diabetic Retinopathy Study letters. Methods: At enrollment, patients were assigned to study eye treatment with abicipar 2 mg every 8 weeks after initial doses at baseline and weeks 4 and 8 (abicipar Q8, n = 630), abicipar 2 mg every 12 weeks after initial doses at baseline and weeks 4 and 12 (abicipar Q12, n = 628), or ranibizumab 0.5 mg every 4 weeks (ranibizumab Q4, n = 630). Main outcome measures: Efficacy measures included stable vision (<15-letter loss in BCVA from baseline) and change from baseline in BCVA and central retinal thickness (CRT). Safety measures included adverse events (AEs). Results: For patients who completed the study, efficacy of abicipar after initial doses was maintained through week 104. At week 104, the proportion of patients with stable vision was 93.0% (396/426), 89.8% (379/422), and 94.4% (470/498); mean change in BCVA from baseline was +7.8 letters, +6.1 letters, and +8.5 letters, and mean change in CRT from baseline was -147 μm, -146 μm, and -142 μm in the abicipar Q8 (14 injections), abicipar Q12 (10 injections), and ranibizumab Q4 (25 injections) groups, respectively. The overall incidence of intraocular inflammation (IOI) AEs was 15.4%, 15.3%, and 0.3% from baseline through week 52 and 16.2%, 17.6%, and 1.3% from baseline through week 104 in the abicipar Q8, abicipar Q12, and ranibizumab Q4 groups, respectively. Conclusions: Two-year results show efficacy of abicipar Q8 and Q12 in nAMD. First onset of IOI events with abicipar was much reduced in the second year and comparable with ranibizumab (0.8% and 2.3% vs. 1.0%). The extended duration of effect of abicipar allows for quarterly dosing and reduced treatment burden.