Dry eye disease & corneal surface disease
DEWS II-classified ocular surface disease — aqueous-deficient, evaporative, or MGD-dominant subtypes — plus neurotrophic keratitis as the closest peptide-to-FDA-approval indication in the library (Tβ4 / RGN-259 Phase 3).
What changes during this transition
Dry eye disease is the most ophthalmology-coordinated axis in the substrate library — DEWS II 2017 classification (aqueous-deficient vs evaporative vs MGD-dominant) is the load-bearing diagnostic frame and changes the intervention sequence at every tier. Standard-of-care is layered and well-evidenced. Tier 1 first-line: artificial tears (preservative-free when dosing exceeds 4×/day per the 2023 CDC guidance after the EzriCare/Delsam Pharma Pseudomonas aeruginosa contamination outbreak with confirmed deaths and vision loss), lid hygiene, warm compresses for MGD, omega-3 supplementation (DREAM trial 2018 returned a negative result against placebo on primary endpoints but the supplementation remains widely used). Prescription tier: cyclosporine 0.05% (Restasis) since 2003 and 0.09% (Cequa) since 2018, lifitegrast 5% (Xiidra) since 2016, perfluorohexyloctane (Miebo) FDA-approved August 2023 for the evaporative DED subtype specifically. Procedural and severe-disease tier: punctal plugs for aqueous-deficient disease, autologous serum tears, amniotic membrane (PROKERA), scleral lenses for severe ocular surface disease. Neurotrophic keratitis is a distinct disease with its own intervention sequence — Mackie staging I/II/III by corneal sensitivity loss and epithelial breakdown, cenegermin (Oxervate, recombinant human NGF) FDA-approved 2018 as the dedicated NK therapy. International standard-of-care additions include diquafosol (Diquas, Japan/Korea/China since 2010) and rebamipide (Mucosta ophthalmic suspension, Japan/Korea/China) — both registered for DED outside the US with the cross-jurisdictional evidence base the US dossier doesn't carry. The peptide library has one peptide with a serious ophthalmic translation footprint: TB-500 / thymosin β-4. RegeneRx and joint-venture partner ReGenTree pushed full-length recombinant Tβ4 as a 0.1% preservative-free eye drop (RGN-259 / OPK-0001) through ARISE-1, ARISE-2, and ARISE-3 in the United States for neurotrophic keratitis, with a parallel Phase 3 program in Korea (Yuyu Pharma partnership) in environmentally challenged dry-eye populations. This is the closest the library gets to FDA approval for any ophthalmic indication — the regulatory pathway is active, the Phase 3 signal in the partner-jurisdiction DED program reads positive on corneal staining, and the mechanism story (actin sequestration accelerating corneal epithelial cell migration, anti-inflammatory cytokine modulation against the IL-1 / TNF-α / MMP-9 axis, VEGF support of limbal stem cells in NK) aligns tightly with what the DEWS II framework identifies as the pathophysiologic targets. The editorial register on this trigger has to honor that footprint — TB-500's dry-eye case is structurally different from BPC-157, GHK-Cu, Selank, and larazotide, which sit on community extrapolation and mechanism speculation without ophthalmic trial bridges. The load-bearing critique that still holds for Tβ4: the compound community-sold as 'TB-500' is the 17–23 actin-binding fragment, not the full-length Tβ4 used in RGN-259 trials; the fragment-vs-full-length distinction is routinely collapsed in community discourse; ophthalmic indications were trialed as preservative-free eye drops, NOT as subcutaneous injections; and cenegermin (Oxervate) is the FDA-approved NK treatment Tβ4 sits adjacent to, not above. The other four library peptides on this axis are substrate-only — surfaced for honest /ask answers when users probe, not elevated as discovery options. GHK-Cu's case is extrapolated from cosmetic-dermatology and wound-healing evidence with no ophthalmic Phase 2 or 3 bridge. BPC-157's case runs on systemic anti-inflammatory community framing without rodent corneal-surface models in the Sikiric foundational corpus or characterized ocular PK. Selank's case is the most tangential — central fatigue / anxiety overlay framing that doesn't engage with the ocular-surface pathology itself. Larazotide's case is a 'Sjögren's + leaky gut' framing that is mechanism-misaligned with the actual B-cell-driven autoimmune exocrinopathy. None of them substitute for the FDA-approved prescription tier or the ophthalmology-managed workup.
Important caveat
Dry eye disease deserves ophthalmology coordination — peptides don't replace DEWS II classification, the cyclosporine / lifitegrast / Miebo prescription tier, cenegermin (Oxervate) for neurotrophic keratitis specifically, or the procedural tier (punctal plugs, scleral lenses, autologous serum tears) for severe disease. Sjögren's syndrome is a distinct autoimmune exocrinopathy with ACR/EULAR 2016 classification criteria, anti-Ro/anti-La serology, and rheumatology-managed standard-of-care (hydroxychloroquine, methotrexate, rituximab for severe systemic disease; pilocarpine and cevimeline for sicca symptoms) — if there's any clinical suspicion (parotitis, arthralgias, fatigue, positive Schirmer), the workup belongs upstream of any peptide conversation. Neurotrophic keratitis is a different disease from generic DED — Mackie staging by corneal sensitivity loss is the diagnostic frame and cenegermin is the FDA-approved Tier 1; TB-500 / RGN-259 sits adjacent to that approved therapy, not above it. Preservative-free artificial tears are the standard for any user dosing >4×/day per 2023 CDC guidance after the EzriCare/Delsam Pharma Pseudomonas contamination outbreak (confirmed deaths and vision loss); compounded ophthalmic preparations belong with a compounding pharmacy holding ophthalmic-formulation accreditation, not with wellness clinics. WADA athletes: TB-500 is S2-prohibited regardless of indication including ophthalmic, BPC-157 is S0-prohibited, and that conversation belongs with the federation anti-doping liaison BEFORE any compounded ophthalmic formulation. Cancer-history users: ocular surface squamous neoplasia (OSSN) history is a hard contraindication for any topical peptide on the ocular surface; oncology coordination is the conservative posture for any prior cancer regardless.
Peptides editorially relevant to dry eye disease & corneal surface disease
1 peptide from the library — each evidence-tiered honestly.
Want this list to grow? The library is editorial — if there’s a peptide you think belongs on this page with documented or mechanistically-clear evidence, send us a note with the citation and we’ll review it under the same evidence-tier discipline as every other entry.