L-serine for MacTel

(SEErine Trial)

Not yet recruiting at 11 trial locations

Age: 18+

Sex: Any

Trial Phase: Phase 3

Sponsor: The Lowy Medical Research Institute Limited

Must not be taking: Fibrates, Tamoxifen, Chloroquine, others

Disqualifiers: Pregnancy, Diabetes, Cancer, Liver disease, others

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 6

Duration: 24 months

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores whether L-serine, an amino acid supplement, can slow the progression of MacTel type 2, a rare eye disease affecting the retina. Researchers aim to determine the safety of long-term L-serine use and its effectiveness compared to a placebo, which resembles the supplement but lacks active ingredients. Individuals diagnosed with MacTel type 2 who have clear vision in at least one eye may qualify for this study. Participants will take either L-serine or a placebo twice daily for two years and visit the clinic every six months for check-ups. As a Phase 3 trial, this study represents the final step before FDA approval, offering participants a chance to contribute to a potentially groundbreaking treatment.

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you cannot participate if you have taken certain medications like serine, glycine, fibrates, tamoxifen, chloroquine, or retinotoxic substances recently. It's best to discuss your current medications with the trial team to see if they might affect your eligibility.

Is there any evidence suggesting that L-serine is likely to be safe for humans?

Research shows that L-serine, a type of amino acid, is under study to determine if it can safely and effectively slow eye disease in people with MacTel type 2. In earlier studies, most participants tolerated L-serine well, and no major safety issues were reported.

L-serine occurs naturally in the body, which may enhance its safety profile. However, like any treatment, monitoring remains crucial. Researchers regularly check clinical trial participants for side effects. Although long-term safety data is still being gathered, early results suggest that L-serine is a safe option for those with MacTel. ^{1 2 3 4 5}

Why do researchers think this study treatment might be promising for MacTel?

Unlike the standard treatments for Macular Telangiectasia Type 2 (MacTel), which typically involve therapies like anti-VEGF injections or laser photocoagulation, L-serine offers a unique approach by potentially addressing the condition at a metabolic level. L-serine is an amino acid that may help protect nerve cells in the retina, which researchers believe could slow or prevent the progression of MacTel. This new mechanism of action is what excites researchers, as it could lead to a more effective and less invasive treatment option for patients with this challenging eye condition.

What evidence suggests that L-serine might be an effective treatment for MacTel?

Research has shown that L-serine, which participants in this trial may receive, might help slow the progression of Macular Telangiectasia Type 2 (MacTel). In earlier studies, patients taking serine experienced a noticeable slowdown in the loss of the ellipsoid zone, a part of the retina crucial for eye health. One study found a 52% reduction in this damage, while another reported a 31% decrease compared to those not taking serine. These findings suggest that L-serine could help preserve vision for people with MacTel. ^{1 3 6 7 8}

Are You a Good Fit for This Trial?

This trial is for adults with MacTel type 2 who can consent to the study, have clear vision media for imaging, and reliable contraception if applicable. They must be able to follow the protocol, fast before blood tests, and already be part of or joining the NHOR with confirmed MacTel type 2 in at least one eye.

Inclusion Criteria

I can read and understand the consent form and agree to its conditions.

I am 18 years old or older.

My eyes are clear enough for high-quality imaging.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Treatment

Participants receive oral serine or placebo twice a day for 24 months

24 months

4 visits (in-person), with telephone contacts between visits

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

1 follow-up telephone contact

What Are the Treatments Tested in This Trial?

Interventions

• L-serine

Trial Overview

The trial is testing whether taking L-serine orally twice daily over two years helps slow down vision loss in people with MacTel compared to a placebo. Participants will undergo regular eye exams, imaging, blood tests and keep a diary of symptoms.

How Is the Trial Designed?

Group I: L-serine Experimental Treatment 1 Intervention

Participant receives oral L-serine

Group II: Placebo Placebo Group 1 Intervention

Participant receives placebo

Who Is Running the Clinical Trial?

The Lowy Medical Research Institute Limited

Lead Sponsor

Trials

8

Recruited

430+

Citations

1.

clinicaltrials.gov

clinicaltrials.gov/study/NCT07342439?term=TREATMENt

Study of Serine Supplementation to Protect Vision in MacTel

This study is a randomized, double-masked, placebo-controlled, parallel-group clinical trial designed to evaluate the effect of oral serine ...

2.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC7945323/

Genetic disruption of serine biosynthesis is a key driver of ...

Macular telangiectasia type 2 (MacTel) is a rare, heritable and largely untreatable retinal disorder, often comorbid with diabetes.

3.

reviewofophthalmology.com

reviewofophthalmology.com/article/update-on-macular-telangiectasia-type2-mactel

Update on Macular Telangiectasia Type-2 (MacTel)

The study showed that in addition to significantly less loss of area of EZ loss, the intervention also preserved retinal sensitivity on ...

4.

clinicaltrials.ucbraid.org

clinicaltrials.ucbraid.org/trial/NCT07342439

Study of Serine Supplementation to Protect Vision in MacTel

The goal of this clinical trial is to look at the efficacy and safety of giving oral serine (an amino acid) on the progression of structural ...

5.

ophthalmologytimes.com

ophthalmologytimes.com/view/angiogenesis-2025-encapsulated-cell-therapy-for-mactel-shows-long-term-efficacy-in-phase-3-trials

Angiogenesis 2025: Encapsulated cell therapy for MacTel ...

One trial showed a 52% reduction in the progression of ellipsoid zone loss, whereas the other showed a 31% reduction, both statistically ...

6.

lmri.net

lmri.net/mactel-safe-study/

MacTel SAFE Study

The study aims to determine the effect of serine and/or fenofibrate on circulating metabolite and lipid levels in patient blood.

7.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC7685488/

Serine and Lipid Metabolism in Macular Disease and ...

Genomic DNA from patients with macular telangiectasia type 2 and their family members was analyzed by exome sequencing. Exome sequence was captured with SeqCap ...

8.

mcw.edu

mcw.edu/departments/ophthalmology-eye-institute/research/research-studies-list/mactel-safe

MacTel SAFE Study

Purpose of study: This project is being done so that scientist can study the effects of the drugs serine and fenofibrate on lipids (fats) in the blood of ...