Key takeaways:

• Preservative-free latanoprost comparably lowered IOP and reduced risk for adverse events compared with preserved latanoprost.
• This offers another treatment option for patients sensitive to preservatives.

Preservative-free latanoprost improved IOP as effectively as preserved latanoprost while improving ocular safety among patients with glaucoma and ocular hypertension, according to a study published in Journal of Glaucoma.

“Our findings support preservative-free latanoprost as an effective first-line option for lowering intraocular pressure, especially for patients with ocular surface disease, dry eye symptoms, preservative intolerance or those expected to require long-term topical therapy,” Hashem Abu Serhan, MD, FICO, FIOF, of the department of ophthalmology at Hamad Medical Corp. in Doha, Qatar, told Healio.

Preservative-free latanoprost lowered IOP while improving tolerability among patients with glaucoma and ocular hypertension. Image: Adobe Stock

Benzalkonium chloride (BAK) — the most common preservative used in latanoprost formulations — has been linked to ocular surface toxicity, tear film instability and chronic conjunctival inflammation, especially with long-term use, Serhan added. But, there had been limited research on the safety and efficacy of preservative-free latanoprost (PFL) compared with persevered latanoprost (PL).

To address the gap, researchers conducted a systematic review and meta-analysis of 10 randomized controlled trials published between 2013 and 2025 that compared PFL with PL among 1,880 patients (women, n = 954; mean age, 64.5 years) with primary open angle glaucoma (POAG) or ocular hypertension (OHT) from the United States, India, South Korea and Europe.

The study’s outcomes of interest included IOP reduction and/or the occurrence of ocular adverse events (OAEs) at 1, 2, 4, 6, 8 and 12 weeks.

Serhan and colleagues employed the inverse-variance method to calculate mean differences (MDs) in their analysis of IOP reduction.

Overall, the researchers found that after 2 weeks, PL was more effective in lowering IOP than PFL, with a 0.43 mm Hg MD between the groups.

Despite this early improvement, the MDs between the two formulations were not statistically significant at 4 weeks (MD, 0.03 mm Hg), 6 weeks (MD, 0.14 mm Hg) or 12 weeks (MD, 0.22 mm Hg).

Serhan and researchers calculated pooled risk ratios for eight OAEs and concluded that the use of PFL commonly resulted in lower incidence of any OAE than PL (RR= 0.81), although this rate was not statistically significant. Individually, only risk for ocular surface hyperemia appeared significantly lower with PFL (RR = 0.66; 95%).

Although PFL was related to less frequent OAEs, discontinuations were uncommon overall and occurred across both groups.

“Since glaucoma treatment is typically lifelong, even modest improvements in ocular comfort may enhance patients' quality of life and potentially improve adherence to treatment,” Serhan said. “However, it is important to note that individual patient factors and medication availability should also be considered when selecting therapy.”

The researchers noted several limitations, including high costs of PFL, the abbreviated follow-up, procedural concerns with the randomization methods of the selected studies and the limited number of studies per outcome.

“While treatment decisions should always be individualized, our results suggest that when preservative-free formulations are available and accessible, they may offer an opportunity to improve ocular surface health without compromising glaucoma control,” Serhan said. “Future large-scale randomized trials with longer follow-up will further clarify the long-term clinical benefits and cost-effectiveness of preservative-free therapy.”

For more information:

Hashem Abu Serhan, MD, FICO, FIOF, can be reached at habuserhan@hamad.qa.