The Resta Study: A Comparison Of Two Preservative-Free Artificial Tears With Sodium Hyaluronate For Relief Of Dry Eye

Evaporation and renewal of the tear film can be altered by multiple factors; thus, in dry eye disease, restoring a functional tear film can be a complex challenge. Traditionally, dry eye relief has been provided by water-based artificial tears (ATs), but ATs with lipid components have emerged more recently to provide lubrication while decreasing tear evaporation. This study compared the performance and safety of two preservative-free ATs with sodium hyaluronate (SH) in patients with moderate-to-severe dry eye disease: a multicomponent 0.24% SH eye drop with carbomer and triglycerides as lipids (SH-CB-TG), and an aqueous-based comparator (C‑SH) with 0.18% SH.

The RESTA (Relief of Eye Surface by Triple Action) study was a multicentre, investigator-masked, noninferiority study conducted at 16 centres in France and approved by an independent ethics committee (CPP SOOM IV: Comité de Protection des Personnes du Sud-Ouest et Outre Mer IV).

Following a 2-week washout period with povidone 2%, up to 6 drops daily, participants were randomised 1:1 to receive SH‑CB-TG or C-SH. Each study drop was administered 3–6 times daily for a duration of 3 months. The primary endpoint was change from Baseline in the ocular surface fluorescein staining (OSFS) score (0–15 per the Oxford scheme) at Day 28 in the per-protocol population. Secondary endpoints included OSFS at 3 months, tear film break-up time, dry eye symptoms, quality-of-life questionnaire and frequency of AT instillation.

On Day 28, in the SH-CB-TG group (n=45), OSFS score decreased from a Baseline of 5.7±1.2 to 3.6±1.6. In the C-SH group (n=34), it decreased from 5.8±1.3 to 4.3±2.1 (95% confidence interval of the adjusted difference was below the predetermined value for noninferiority). In both groups, signs, symptoms and quality-of-life measures improved continuously through the study, with a favourable safety profile. While not statistically significant, a higher proportion of patients in the SH-CB-TG group (vs. C-SH), strongly agreed that instillation of the study AT was comfortable at all timepoints. In the SH-CB-TG group, the global score of dry eye symptoms showed a statistically significant improvement compared with the C-SH group (p<0.05).

The multicomponent, lipid-containing SH-CB-TG was noninferior to the aqueous-based tear substitute in the studied population and may offer additional advantages in ameliorating symptoms of dry eye.