Cancer Drug PRL3-zumab Shows Promise as Novel Treatment for Blinding Eye Diseases

Researchers in Singapore have uncovered a promising new therapeutic use for PRL3-zumab, an experimental cancer drug originally developed at the ASTAR Institute of Molecular and Cell Biology (ASTAR IMCB). In preclinical studies, the drug demonstrated significant potential in treating two of the most common causes of blindness: wet age-related macular degeneration (AMD) and diabetic retinopathy.

Published in Nature Communications, the findings by scientists at A*STAR IMCB and Intra-ImmuSG (IISG) point to a novel treatment pathway for patients who do not respond well to current standard-of-care therapies.

A New Approach to Address Current Treatment Gaps

Standard therapies for wet AMD and diabetic retinopathy often require monthly intravitreal injections, which are not only invasive but also carry risks such as infection and lens damage. Moreover, up to 45% of patients show limited or no response to these treatments, underscoring the urgent need for alternative therapeutic strategies.

PRL3-zumab offers a differentiated solution: it can be administered intravenously. In preclinical models, intravenous delivery of PRL3-zumab achieved an 86% greater reduction in blood vessel leakage compared to conventional eye injections. This delivery method also showed more sustained therapeutic levels in ocular tissues, potentially reducing the risk of complications associated with direct injections into the eye.

Preparing for Human Trials in Singapore

Following approval from the Health Sciences Authority (HSA) of Singapore on June 16, 2025, preparations are underway to begin clinical trials of PRL3-zumab in ophthalmic indications by late 2025. These upcoming studies represent a critical milestone in validating PRL3-zumab’s efficacy and safety profile for eye diseases.

Importantly, PRL3-zumab has already completed Phase II trials in cancer patients, where it demonstrated a favorable safety profile. This background data supports its potential application in ophthalmology, offering a head start in the clinical development process.

From Oncology to Ophthalmology: Exploring PRL3-zumab’s Potential in Eye Disease

The therapeutic journey of PRL3-zumab highlights the translational value of cancer research in advancing other fields of medicine. The PRL3 protein, originally identified in 1998 by Professor Qi Zeng, Senior Principal Scientist at A*STAR IMCB and founder of IISG, was initially studied for its role in cancer metastasis. Over time, researchers discovered PRL3’s unexpected involvement in vascular abnormalities linked to eye disease.

“When I first identified PRL3 over two decades ago, I never imagined that our cancer research could also provide hope for patients facing blindness,” said Professor Qi Zeng, senior author of the study. “Seeing PRL3-zumab now potentially transform treatment for devastating eye conditions shows how fundamental scientific discoveries can lead to life-changing outcomes.”

Associate Professor Xinyi Su, Executive Director of A*STAR IMCB and co-author on the study, added:
“The repurposing of PRL3-zumab offers the possibility of a faster, more cost-effective, and potentially safer path to developing treatments for these eye diseases. This is made possible through the close collaborations in Singapore between our scientists, clinicians, and clinician-scientists.”

Looking Ahead

With human trials on the horizon and a robust safety profile already established in oncology, PRL3-zumab may soon represent a major advancement in the treatment of wet AMD and diabetic retinopathy, offering hope to millions of patients worldwide.

Reference:

Ang, K.H. et al. PRL3-zumab as an anti-angiogenic therapy in neovascular eye diseases, Nature Communications (2025). doi.org/10.1038/s41467-025-59929-2