Reviews/Dry Eye Disease Treatment/Perfluorohexyloctane superior to saline in meibomian gland dysfunction
Perfluorohexyloctane · DED-PFHO-02 · v2
Borderline: within 4 points of the Established/Likely boundary, so a re-grade could land either side.
The question is whether perfluorohexyloctane eye drops work better than a saline control for dry eye linked to blocked oil glands in the eyelids. Two large, well-run trials that compared the drops directly against saline, with neither patients nor assessors knowing which was which, both found the drops did better on the two things they measured: how much the eye surface was damaged and how dry the eye felt [2][3]. A follow-on study that kept patients on the drops for a year found the benefit held up, and that people originally on saline also improved once switched to the drops [4]. The improvements over saline were real and statistically reliable but fairly small in size, and both measures are standard stand-ins for the condition rather than long-term outcomes like vision. Because saline itself soothes the eye a little, the gap between the two treatments is modest even though it is consistent.
Two independent, large, double-masked, saline-controlled phase 3 RCTs in dry eye associated with meibomian gland dysfunction each met both co-primary endpoints with statistically significant superiority over saline: in the N=312 trial [2] tCFS change was -3.8 vs -2.7 and dryness -38.6 vs -28.3 (mean differences -1.14, 95% CI -1.70 to -0.57, P<.001; and -12.74, 95% CI -17.20 to -8.28, P<.001), and in the N=620 MOJAVE trial [3] tCFS change was -2.3 vs -1.1 (LS mean treatment difference -1.2, 95% CI -1.7 to -0.8, P<.001) and dryness -29.4 vs -19.2 (difference -10.2, 95% CI -14.4 to -6.1, P<.001). The single-arm 52-week extension KALAHARI [4], which rolled over 208 patients, found the gains maintained and that saline-treated patients improved after switching to the drug. Three further corpus studies [1][5][6] are single-arm with no comparator and cannot address superiority to saline. The contested point: The direction and statistical significance of the result are not in dispute; the contested point is how much the demonstrated difference amounts to. The treatment advantage over saline is modest in absolute terms (e.g. an LS mean tCFS difference of -1.2 in [3]), rests on surrogate sign and symptom endpoints rather than hard functional outcomes, and comes from two trials of one molecule within a single commercial development program, so the independence of the evidence is only partial.
All 6 papers behind this claim with their DOIs and what each does to it, the panel’s arbitration, the evidence gap map and the open research questions. Free, and sent to your inbox.
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The active comparator is hypotonic saline, which has its own lubricating effect; the demonstrated treatment differences (e.g. tCFS LS difference -1.2) are statistically significant but clinically modest.
The two pivotal RCTs [2][3] test the same molecule within one commercial development program, so evidential independence is only partial despite differing geography and trial names.
Where it remains uncertain. The between-group differences are statistically significant but clinically modest (e.g. tCFS LS mean difference -1.2 in [3]), the endpoints are accepted surrogates, and both pivotal trials test the same molecule under one development program.
Aleatory
The treatment advantage over an active saline comparator is small in magnitude (e.g. tCFS LS mean difference -1.2 in [3]; -1.14 in [2]), so individual patient benefit over saline varies and is not large.
The load-bearing papers from a corpus of 6, each classified by what it does to the claim. Every DOI is taken from the corpus the claim was graded on.
Direct RCT evidence of superiority over 0.6% NaCl on both co-primary endpoints in MGD-associated DED.
“changes from baseline at day 57 of tCFS score (mean [SD], -3.8 [2.7] vs -2.7 [2.8]) and eye dryness score (mean [SD], -38.6 [21.9] vs -28.3 [20.8]) in the perfluorohexyloctane group were superior to the control group, with estimated mean differences of -1.14 (95% CI, -1.70 to -0.57; P < .001) and -12.74 (95% CI, -17.20 to -8.28, P < .001), respectively”
Panel auditInternal validity: high · scope of inference: Chinese patients with DED associated with MGD over 57 days, signs (tCFS) and symptoms (dryness).Key limitations: single-country population · 57-day duration · authors note need for independent confirmation
Independent large RCT replicating superiority over hypotonic saline on both sign and symptom co-primary endpoints.
“Least-squares (LS) mean change from baseline to week 8 was statistically significantly greater for NOV03 compared with saline for both tCFS (-2.3 vs -1.1; LS mean treatment difference, -1.2 [95% confidence interval -1.7 to -0.8]; P < .001) and visual analog scale dryness score (-29.4 vs -19.2; LS mean treatment difference, -10.2 [95% CI -14.4 to -6.1]; P < .001), with statistically significant between-group differences observed as early as week 2”
Panel auditInternal validity: high · scope of inference: Patients ≥18 with DED and signs of MGD over 8 weeks, signs (tCFS) and symptoms (dryness VAS).Key limitations: 8-week duration · signs/symptoms endpoints only
Supports durability and shows former-saline patients gain further benefit on PFHO, consistent with the superiority signal.
“Patients treated with saline in GOBI and switched to PFHO in KALAHARI showed improvements in total corneal fluorescein staining and visual analog scale scores by week 4 that were maintained for the rest of the study”
Panel auditInternal validity: low · scope of inference: Patients with MGD-associated DED rolled over from GOBI, 52-week safety and maintenance of PFHO.Key limitations: single-arm · open-label · no concurrent saline comparator
3 of 6 papers shown. The full review lists all of them, with the panel’s arbitration →
Claims are graded at each quarterly release, and re-graded between releases only when a pivotal trial lands. Every change is a new version of the claim.
Direct, consistent, statistically significant superiority over saline across two well-designed RCTs carries the claim, tempered by modest effect sizes, surrogate endpoints and partial sponsor independence.
Release 2026-q4 re-graded every claim from its corpus under protocol v0.19. An earlier release's grade is shown for the record; it came from an earlier protocol and is not a movement.
Assumptions that carry weight but are not themselves established.
The panel records the gap that would most move the claim, and the study that would close it.
Hard or functional outcome endpoints. The claim rests entirely on surrogate signs and symptoms [2][3]; whether the drug improves patient-important or functional outcomes over saline is untested. The panel rates this the highest-importance open gap for the claim, and names the study design that would close it: A saline-controlled RCT powered on patient-reported function or a validated hard endpoint rather than tCFS and dryness VAS.
Open question: Does the superiority over saline on surrogate endpoints translate into patient-important or functional benefit? Why it is still open: Both pivotal trials [2][3] report only tCFS and dryness VAS, which the deliberation notes are surrogates.
Priors is a sceptical first reader, not peer review, and not medical advice.
Release 2026-q4 · graded 21 Oct 2026 · protocol v0.19