Safety and Efficacy of ST-100 (Vezocolmitide) Ophthalmic Solution 60 μg/ml Ophthalmic Solution in Subjects Diagnosed With Dry Eye Disease (DED)

Inclusion Criteria:

1. Be at least 18 years of age;
2. Provide written informed consent;
3. Have a reported history of DED for at lease 6 months prior to Visit 1;
4. Have a history of use or desire to use eye drops for DED within 6 months of Visit 1;
5. Report a score of ≥ 2 on the Ora Calibra® Ocular Discomfort & 4-symptom questionnairein at least one symptom pre-CAE® at Visits 1 and 2;
6. Have a Schirmer's Test score of ≤ 10 mm and ≥ 1 mm at Visits 1 and 2;
7. Have a conjunctival redness score ≥ 1 according to the Ora Calibra® ConjunctivalRedness for Dry Eye Scale in at least one eye at pre-CAE® Visits 1 and 2;
8. Have a corneal fluorescein staining score of ≥ 2 in at least one region (e.g.inferior, superior, or central) pre-CAE® at Visits 1 and 2;
9. Have a sum corneal fluorescein staining score of ≥ 4, based on the sum of theinferior, superior, and central regions pre-CAE®, at Visits 1 and 2;
10. Have a total lissamine green conjunctival score of ≥ 2, based on the sum of thetemporal and nasal regions pre-CAE® at Visits 1 and 2;
11. Demonstrates a response to the CAE® at Visits 1 and 2 as defined by: Having at least a ≥1 point increase in fluorescein staining in the inferior region inat least one eye following CAE® exposure Reporting an Ora Calibra® Ocular DiscomfortScore ≥ 3 at 2 or more consecutive time points in at least one eye during CAE®exposure (if a subject has an ocular discomfort rating of 3 at a time = 0 for an eye,they must report an ocular discomfort rating of 4 for two consecutive measurements forthat eye). Note: a subject cannot have an ocular discomfort score of 4 at time = 0);
12. Have at lease one single eye satisfy all criteria for 6, 7, 8, 9, 10 and 11 above.

Exclusion Criteria:

1. Have any clinically significant slit lap findings at Visit 1 that may include activeblepharitis, meibomian gland dysfunction, lid margin inflammation, or active ocularallergies that require therapeutic treatment, and/or in the opinion of theinvestigator may interfere with study parameters;
2. Be diagnosed with an ongoing ocular infection (bacterial, viral, or fungal), or activeocular inflammation at Visit 1;
3. Have worn contact lenses within 7 days of Visit 1 or anticipate using contact lensesduring the study;
4. Have used any eye drops within 2 hours of Visit 1;
5. Have previously had laser-assisted in situ keratomileusis (LASIK) surgery within thelast 12 months;
6. Have used Restasis®, Xiidra®, or Cequa® ophthalmic solutions Tyrvaya® nasal spray, orMiebo® or Xdemvy® solution within 45 days of Visit 1;
7. Have any planned ocular and/or lid surgeries over the study period or any ocularsurgery within the last 6 months;
8. Have used, are using or anticipate using permanent or temporary punctal plugs duringthe study within 90 days of Visit 1;
9. Be currently taking any topical ophthalmic prescription (including medications forglaucoma) or over-the-counter solutions, artificial tears, gels or scrubs, or using amoisture chamber and cannot discontinue these medications for the from Visit 1 untilafter Visit 8 of the trial (excluding medications allowed for the conduct of thestudy);
10. Be currently taking or have taken Omega-3 supplements within the last 3 months;
11. Be currently taking of have taken CHANTIX® (varenicline) tablets within 6 months priorto Visit 1 that is not on a stable dose. The dose cannot change during the conduct ofthe study;
12. Have corrected visual acuity (VA) greater than or equal to logarithm of the MinimumAngle of Resolution (logMAR) +0.7 as assessed by Early Treatment of DiabeticRetinopathy Study (ETDRS) scale in both eyes at Visit 1;
13. Be a woman who is pregnant, nursing, or planning a pregnancy during the study;
14. Be unwilling to submit a urine pregnancy test at Visit 1 and Visit 8 (or earlytermination visit) if of childbearing potential. Non-childbearing potential is definedas a woman who is permanently sterilized (hysterectomy, bilateral salpingectomy,bilateral oophorectomy at least 6 months prior to dosing), or is post-menopausal (where post-menopausal is defined as no menses for 12 months without an alternativemedial cause);
15. Be a woman of childbearing potential who is not using an acceptable means of birthcontrol; acceptable methods of contraception includes: hormonal - oral, implantable,injectable, or transdermal contraceptives for at least one month prior to first visit;Use two of the following effective methods of contraception: intrauterine device (IUDwithout local hormone release), diaphragm, cervical cap, and/or condoms; or surgicalsterilization of partner (i.e., a female participant's male partner has undergoneeffective surgical sterilization such as vasectomy before the female participantentered the clinical trial) who has obtained documentation of absence of sperm in hisejaculate and is the sole sexual partner of the female participant during the clinicaltrial. For non-sexually active females, abstinence may be regarded as an adequatemethod of birth control; however, if the subject becomes sexually active during thestudy, she must agree to use adequate birth control as defined above for the remainderof the study;
16. Have a known allergy and/or sensitivity to the Study Drug or its components;
17. Have a condition or be in a situation that the investigator feels may put the subjectat significant risk, may confound the study results, or may interfere significantlywith the subject's participation in the study;
18. Be currently enrolled in an investigational drug or device study or have used aninvestigational drug or device within 30 days of Visit 1;
19. Be currently using any medication known to cause ocular drying that is not used on astable dosing regimen for the least 30 dats prior to Visit 1;
20. Have a known history of meibomian gland procedures (e.g. LipiFlow, laser peripheraliridotomy (LPI), probing, etc.) within 6 months of study enrollment;
21. Be unable or unwilling to follow instructions, including participation in all studyassessments and visits;
22. Has participated in any other clinical trials of ophthalmologic drugs for 30 daysbefore or during participation in this Study.