Safety and Efficacy of NPI-001 Tablets for RP Associated With Usher Syndrome

Brief Title

Safety and Efficacy of NPI-001 Tablets for RP Associated With Usher Syndrome

Official Title

Safety and Efficacy of NPI-001 Tablets Versus Placebo for Treatment of Retinitis Pigmentosa Associated With Usher Syndrome

Brief Summary

      This study will examine the safety and efficacy of NPI-001 Tablets as compared to placebo for
      24 months in subjects with vision loss due to RP associated with Usher syndrome.

Detailed Description

      This study will examine the safety and efficacy of oral NPI-001 Tablets as compared to oral
      placebo tablets for 24 months in subjects with vision loss due to RP associated with Usher

Study Phase

Phase 1/Phase 2

Study Type


Primary Outcome

Evaluate change from baseline for retinal sensitivity assessed by microperimetry of active versus placebo


Usher Syndromes



Study Arms / Comparison Groups

Description:  NPI-001 Tablet, 250 mg, BID


* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.

Recruitment Information

Recruitment Status


Estimated Enrollment


Start Date

September 3, 2020

Completion Date

September 2023

Primary Completion Date

September 2023

Eligibility Criteria

        Inclusion Criteria:

          1. Male or female, age ≥18 years.

          2. Able to comprehend and willing to sign an informed consent form (ICF) and to adhere to
             the study protocol.

          3. Diagnosed with Usher syndrome.

          4. EZ zone with width ≥500 microns, which includes the fovea in each eye at Visit 2,
             (Screen B).

          5. Have at least 20 detectable points on the MAIA grid.

          6. On stable dose of medications associated with other conditions for at least one month.

          7. Both female participants of childbearing potential and male participants able to
             father children must have (or have a partner who has) had a bilateral oophorectomy,
             hysterectomy or bilateral salpingectomy; must abstain from intercourse; or must agree
             to practice 2 acceptable methods of contraception throughout the course of the study
             and 4 weeks after the last visit. Acceptable methods of contraception include hormonal
             contraception (i.e., birth control pills, injected hormones, dermal patch or vaginal
             ring), intrauterine device, barrier methods (diaphragm, condom) with spermicide, tubal
             ligation, or vasectomy.

        Exclusion Criteria:


          1. All edges of the EZ area in both eyes cannot be visualized at Visit 2 (Screen B).

          2. Concurrent retinal pathologies that result in vision loss or inability to fixate,
             including but not limited to, choroideremia, retinal vein occlusion, and neovascular
             age-related macular degeneration.

          3. Intraocular surgery within the last two months or capsulotomy within the last month.

          4. History of uveitis, Coat's disease, diabetic retinopathy, glaucoma, herpes simplex of
             the eye, or currently has a cataract that prevents visualization of the posterior

          5. Unstable fixation during microperimetry in either eye at either screening or baseline


          6. Use of any other investigational new drug, or participation in another clinical trial
             within 12 weeks before the start of study treatment.

          7. Use of N-acetylcysteine containing products in the previous 30 days prior to the
             baseline visit or unwilling to refrain from such supplements for the duration of the

          8. Liver or kidney disease, cystic fibrosis, asthma or chronic obstructive pulmonary
             disease (COPD), history of thrombocytopenia not due to a reversible cause, or other
             blood dyscrasia.

          9. Suspected liver dysfunction determined by having alanine aminotransferase (ALT),
             aspartate aminotransferase (AST), or bilirubin values > 1.5 X the upper limit of
             normal (ULN).

         10. Platelet or hemoglobin values that are below the lower limit of normal at screening
             (subjects with normal hemoglobin and mean corpuscular volume below the lower limit of
             normal should have iron studies performed to ensure that they are iron replete before
             taking part in the study), or neutrophils or white cell count which is above the upper
             limit of normal.

         11. Presence of more than + proteinuria on urinalysis at screening or (confirmed by
             abnormal albumin creatinine ratio).

         12. Presence of hematuria on urinalysis at screening. (If hematuria is detected on
             urinalysis, then the specimen should be subjected to microscopy, and subject should be
             excluded if more than 10 X 106 red blood cells/L.) If the subject is a female in whom
             the hematuria may be due to menses, then the urinalysis can be repeated after a few

         13. C-reactive protein (CRP) value above 10 mg/L.

         14. Subject has a recent history of presence of gross blood in stools.

         15. History of known sensitivity to N-acetylcysteine or similar thiol compounds.

         16. History of hypersensitivity to any medication or food resulting in systemic symptoms.

         17. History of cancer (other than non-melanoma skin cancer) diagnosed or requiring
             treatment within the past 2 years.

         18. Pregnant women or women planning to become pregnant in the next 25 months or men with
             partners planning to become pregnant in the next 25 months.

         19. Lactating women who are breast-feeding.

         20. A potential participant lives in the same household as a current participant in this

         21. Inability to provide blood samples, including difficulty with venous access.

         22. Any reason, in the opinion of the Principal Investigator, the subject should not




18 Years - N/A

Accepts Healthy Volunteers



Lee Anderson, MD, +1-817-336-3000, [email protected]

Location Countries


Location Countries


Administrative Informations



Organization ID


Responsible Party


Study Sponsor

Nacuity Pharmaceuticals, Inc.


 Foundation Fighting Blindness

Study Sponsor

Lee Anderson, MD, Study Chair, Nacuity Pharmaceuticals, Inc.

Verification Date

June 2021