A study to assess the safety and efficacy of K-321 in participants with FECD after descemetorhexis.

Inclusion Criteria:

• Is at least 18 years old at the screening visit (Visit 1)
• Has a diagnosis of FECD at Visit 1
• Meets all other inclusion criteria outlined in clinical study protocol

Exclusion Criteria:

• Is a female patient of childbearing potential and any of the following is true:

  1. is pregnant or lactating/breastfeeding, or
  2. is not surgically sterile, not post-menopausal (no menses for the previous 12 months), or not practicing an effective method of birth control as determined by the Investigator (eg, oral contraceptives, double barrier methods, hormonal injectable or implanted contraceptives, tubal ligation, or partner with vasectomy)

• Has a study eye with a history of cataract surgery within 90 days of Visit 1

• Meet any other exclusion criteria outlined in clinical study protocol