For many years now, panretinal photocoagulation (PRP) has been the cornerstone of proliferative diabetic retinopathy (PDR) management – but new data from the phase 3 CONDOR trial suggest anti-VEGF therapy may offer a compelling alternative for PDR treatment.
In this large, global randomized clinical trial involving 689 treatment-naïve patients with PDR, investigators compared intravitreal brolucizumab (6 mg) with PRP over 54 weeks. The study is notable not only for its scale – spanning 152 sites across 16 countries – but also for its focus on patients without prior laser treatment, helping to address limitations seen in earlier anti-VEGF trials.
Visual acuity and disease control
The primary endpoint – change in best-corrected visual acuity (BCVA) – favored brolucizumab. Patients receiving the anti-VEGF agent maintained vision, with a mean gain of 0.2 letters, while those treated with PRP experienced a decline of 4.2 letters. This translated into a statistically significant difference of 4.4 letters, confirming both noninferiority and superiority of brolucizumab at week 54.
Beyond visual acuity, disease regression was more pronounced in the PRP arm. As illustrated in the study, 63.6% of patients treated with brolucizumab had no evidence of PDR at week 54, compared with 22.4% in the PRP group – a nearly 40% absolute difference.
The benefits of brolucizumab also extended to structural outcomes. Rates of center-involved diabetic macular edema (CI-DME) were markedly lower with brolucizumab (31.1% vs 72.7%), and fewer patients experienced vision-threatening complications such as vitreous hemorrhage or retinal detachment.
Reducing treatment burden?
One of the more intriguing aspects of CONDOR is its dosing regimen. Brolucizumab was administered every six weeks during loading, followed by 12-week maintenance intervals – with the potential to extend dosing out to 24 weeks based on disease activity. This contrasts with earlier anti-VEGF trials in PDR, which typically required monthly injections during the loading phase.
For clinicians, this raises the possibility of reduced treatment burden compared with other anti-VEGF strategies – though adherence to follow-up remains critical when moving away from the “one-and-done” nature of PRP.
Safety considerations
As expected, safety signals warrant careful interpretation. Overall ocular adverse events were less frequent in the brolucizumab arm (34.3% vs 49.1% with PRP). However, intraocular inflammation – including retinal vasculitis – was observed in 5.2% of brolucizumab-treated patients, compared with 0.6% in the PRP group.
This aligns with the known safety profile of brolucizumab and reinforces the need for vigilance when selecting patients and monitoring treatment.
A shifting treatment paradigm?
PRP remains an effective, durable intervention, but it is not without drawbacks – including peripheral visual field loss, night vision impairment, choroidal effusions, and risk of exacerbating macular oedema. Anti-VEGF therapies, by contrast, offer the potential to not only stabilize but reverse disease activity.
CONDOR adds to a growing body of evidence supporting this shift. Unlike earlier studies such as Protocol S and CLARITY, which included patients with prior treatments or concurrent DME, this trial provides a clearer head-to-head comparison in a more treatment-naïve population.
The study authors conclude that brolucizumab may represent a viable alternative to PRP for selected patients with PDR, stating that “results from the future 96-week analysis [of the CONDOR trial] will provide further insight into the longer-term efficacy of brolucizumab and its potential to improve visual outcomes with a manageable treatment burden in patients with PDR.”
For now, the findings highlight an evolving landscape in PDR management – one increasingly defined by pharmacologic precision rather than laser ablation.
