Biosimilars of anti-vascular endothelial growth factor for ophthalmic diseases: A review.

The development of intravitreally injected biologic medicines (biologics) acting against vascular endothelial growth factor (VEGF) substantially improved the clinical outcomes of patients with common VEGF-driven retinal diseases. The relatively high cost of branded agents, however, represents a financial burden for most healthcare systems and patients, likely resulting in impaired access to treatment and poorer clinical outcomes for some patients. Biosimilar medicines (biosimilars) are clinically equivalent, potentially economic alternatives to reference products. Biosimilars approved by leading health authorities have been demonstrated to be similar to the reference product in a comprehensive comparability exercise, generating the totality of evidence necessary to support analytical, pre-clinical, and clinical biosimilarity. Anti-VEGF biosimilars have been entering the field of ophthalmology in the US since 2022. We review regulatory and scientific concepts of biosimilars, the biosimilar development landscape in ophthalmology, with a specific focus on anti-VEGF biosimilars, and discuss opportunities and challenges facing the uptake of biosimilars.

Biosimilar SB15 versus reference aflibercept in neovascular age-related macular degeneration: 1-year and switching results of a phase 3 clinical trial.

BACKGROUND/AIMS: To evaluate efficacy, safety, pharmacokinetics (PK) and immunogenicity of SB15 versus reference aflibercept (AFL), and switching from AFL to SB15 in neovascular age-related macular degeneration (nAMD). DESIGN: Prospective, double-masked, randomised, phase 3 trial. METHODS: Participants with nAMD were randomised 1:1 to receive SB15 (N=224 participants) or AFL (N=225). At week 32, participants either continued on SB15 (SB15/SB15, N=219) or AFL (AFL/AFL, N=108), or switched from AFL to SB15 (AFL/SB15, N=111). This manuscript reports 1-year and switching results of secondary efficacy endpoints such as changes from baseline to week 56 in best-corrected visual acuity (BCVA), central subfield thickness (CST, from internal limiting membrane (ILM) to retinal pigment epithelium), and total retinal thickness (TRT, from ILM to Bruch's membrane). Additional endpoints included safety, PK and immunogenicity. RESULTS: Efficacy results were comparable between groups. The least squares mean (LSmean) change in BCVA from baseline to week 56 was 7.4 letters for SB15/SB15 and 7.0 letters for AFL/AFL (difference (95% CI)=0.4 (-2.5 to 3.2)). The LSmean changes from baseline to week 56 in CST and TRT were -119.2 µm and -132.4 µm for SB15/SB15 and -126.6 µm and -136.3 µm for AFL/AFL, respectively (CST: difference (95% CI)=7.4 µm (-6.11 to 20.96); TRT: difference (95% CI)=3.9 µm (-18.35 to 26.10)). Switched and non-switched participants showed similar LSmean changes in BCVA from baseline to week 56 (AFL/SB15, 7.9 letters vs AFL/AFL, 7.8 letters; difference (95% CI)=0.0 (-2.8 to 2.8)). Safety, PK and immunogenicity were comparable between groups. CONCLUSIONS: Efficacy, safety, PK and immunogenicity were comparable between SB15 and AFL and between switched and non-switched participants.

Efficacy and Safety of the Aflibercept Biosimilar SB15 in Neovascular Age-Related Macular Degeneration: A Phase 3 Randomized Clinical Trial.

Importance: Aflibercept biosimilars can expand available treatment options in retinal diseases and have the potential to improve patient access to safe and effective therapy. Objective: To establish equivalence in efficacy and similarity in safety, pharmacokinetics, and immunogenicity of SB15 and reference aflibercept (AFL) in neovascular age-related macular degeneration (nAMD). Design, Setting, and Participants: This was a randomized double-masked parallel group phase 3 trial conducted at 56 centers in 10 countries from June 2020 to March 2022, including follow-up through 56 weeks. Of 549 screened participants, 449 participants 50 years and older with treatment-naive nAMD were included and randomly assigned to SB15 (n = 224) or AFL (n = 225). Key exclusion criteria included considerable scarring, fibrosis, atrophy, and hemorrhage. This report includes results up to the end of the parallel group period at week 32. Of the 449 randomized participants, 438 (97.6%) completed week 32 follow-up. Intervention: Participants were randomized 1:1 to receive 2 mg of SB15 or AFL every 4 weeks for the first 12 weeks (3 injections), followed by dosing every 8 weeks up to week 48, with final assessments at week 56. Main Outcomes and Measures: The primary end point was the change in best-corrected visual acuity (BCVA) from baseline to week 8 with predefined equivalence margins of -3 letters to 3 letters. Other key end points were changes in BCVA and central subfield thickness up to week 32, safety, pharmacokinetics, and immunogenicity. Results: The mean (SD) age among the 449 included participants was 74.0 (8.1) years, and 250 participants (55.7%) were female. Baseline demographic characteristics and most disease characteristics were comparable between treatment groups. The least squares mean change in BCVA from baseline to week 8 in the SB15 group was equivalent to that in the AFL group (6.7 letters vs 6.6 letters, respectively; difference, 0.1 letters; 95% CI, -1.3 to 1.4). Comparable efficacy between treatment groups was maintained up to week 32 (least squares mean change from baseline in BCVA: SB15, 7.6 letters vs AFL, 6.5 letters; least squares mean change from baseline in central subfield thickness: SB15, -110.4 µm vs AFL, -115.7 µm). No clinically relevant differences were observed in the incidence of treatment-emergent adverse events (TEAEs) (SB15, 107/224 [47.8%] vs AFL, 98/224 [43.8%]) and ocular TEAEs in the study eye (SB15, 41/224 [18.3%] vs AFL, 28/224 [12.5%]). The serum concentration profiles and cumulative incidences of overall antidrug antibody positive participants were comparable. Conclusions and Relevance: In this phase 3 randomized clinical trial, SB15 and AFL showed equivalent efficacy and comparable safety, pharmacokinetics, and immunogenicity in participants with nAMD. Trial Registration: ClinicalTrials.gov Identifier: NCT04450329.

Clinical manifestation and neuroimaging methods in diagnosing basal ganglia calcifications.

The aim of this case study was to evaluate the clinical symptoms in patients with basal ganglia calcifications and compare the neuroimaging methods used in confirming this state. The clinical status and performed transcranial sonography of basal ganglia structures in patients with brain calcifications found by computed brain tomography was examined. In one of these patients DaTSCAN was performed. A large spectrum of different symptoms was found. Transcranial sonography of basal ganglia showed the hyperechogenicity of nucleus lenticularis in eight out of 10 patients. DaTSCAN, which was performed to one patient with parkinsonian signs and the hyperechogenicity of substantia nigra found by transcranial sonography, was normal. Transcranial sonography is a newly neuroimaging method which can contribute to diagnosing basal ganglia calcifications in patients with different neurological signs. Computed tomography of brain remains the most adequate technique in visualising calcifications.

Effect of intraocular silicone oil on ocular tissue.

The aim of this study was to find out to which extent the instilled silicone oil affects the changes of lens, cornea, and the ocular pressure with regard to its time kept in the operated eye with a lens. The study was carried out on the sample of 40 patients, divided in three groups. The first group of patients with the silicone oil kept in the eye during 3 months, the second one during 3-6 months, and the third one during 6-9 months. Statistically important changes were observed in the progression of the lens opacification with the patients, progressively with the time of keeping the silicone oil in the eye. The followed cornea opacifications and increased ocular pressure were not statistically significantly linked with the length of keeping the silicone oil in the eye, so that it can be concluded that the silicone oil is the best substitute for the vitreous body but it should be removed from the eye, most frequently, in the period of 3-6 months from the date of its instillation, and after 3 weeks at the earliest.