Table 1.

Summary of choroideremia gene therapy trials to date.

Clinicaltrials.gov Identifier and Study Start Date	Phase	Drug Design	Location	Vector	Study Status	Outcome	Reference
01461213 (October 2011)	I/II	r.AAV-REP1	University of Oxford, UK	Subretinal	Completed	3.5 years—Two patients with poor baseline BCVA gained 11 and 21 letters. Three patients with good baseline BCVA maintained BCVA. One patient had a surgical complication leading to a lower dose of the vector and had a decline in BCVA from 6 months to 3.5 years, likely due to degeneration in the fovea.	[20,21,22]
02341807 (January 2015)	I/II	AAV2-hCHM	University of Philadelphia, USA	Subretinal	Active, not recruiting	2 years—unchanged BCVA in 13/15. Acute foveal thinning in one patient. Macular hole in one patient.
02077361 (April 2015)	I/II	r.AAV-REP1	University of Alberta, Edmonton, Alberta, Canada	Subretinal	Completed	2 years—BCVA change of −8 to >15 letters. One serious adverse event: a localized intraretinal immune response.	[23]
02553135 (September 2015)	II	r.AAV-REP1	University of Miami, Miami, USA	Subretinal	Completed	2 years—BCVA change of −1 to +10 letters.	[24]
02671539 (January 2016)	II	r.AAV-REP1	Tuebingen, Germany	Subretinal	Completed	2 years—mean change in BCVA of +3.7 letters.	[25,26]
02407678 (August 2016)	II	r.AAV-REP1	University College London & University of Oxford, UK	Subretinal	Completed	Awaited
03507686 (November 2017)	II	r.AAV-REP1	Gemini, Biogen	Subretinal	Completed	Awaited
03496012 (December 2017)	III	Low-dose and high-dose r.AAV-REP1	STAR, Biogen	Subretinal	Completed	Failed to meet primary and secondary endpoints.
04483440 (June 2020)	1	AAV capsid variant (4D-100) carrying a transgene encoding a codon-optimized human CHM gene	4D Molecular Therapeutics	Intravitreal	Ongoing	Initial clinical safety data at both of the two dose levels in the 4D molecular therapeutics trial indicate that it is well tolerated and did not result in any dose-limiting toxicity (n = 6; all patients followed up for between one and nine months).