Skip to content

Theranostic Guided Riboflavin/UV-A Corneal Cross-linking

Assessment of Theranostic Guided Riboflavin/UV-A Corneal Cross-linking for Treatment of Keratoconus

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05457647
Acronym
ARGO
Enrollment
50
Registered
2022-07-14
Start date
2022-04-27
Completion date
2024-01-26
Last updated
2025-02-11

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Keratoconus

Keywords

theranostics, riboflavin, UV-A light, corneal cross-linking

Brief summary

This is a clinical study consisting of a study arm to validate accuracy and precision of the combined use of theranostic imaging biomarkers, riboflavin score and theranostic score, to assess and predict efficacy of corneal cross-linking in flattening the corneal topography Kmax value at 12-months postoperatively. The objective of the study is to assess the performance of the theranostic software module (Research Use Only) of a CE marked (CE1936) UV-A medical device, C4V CHROMO4VIS™, in order to validate its use for theranostic-guided corneal cross-linking treatment of keratoconus and corneal ectasia. The study hypothesis is that theranostic-guided riboflavin/UV-A corneal cross-linking with the C4V CHROMO4VIS™ system is safe and can estimate treatment efficacy during operation, regardless of treatment protocol, i.e., either with or without epithelial removal.

Detailed description

Keratoconus is a naturally-occurring ocular condition characterized by progressive thinning and steepening of the central cornea, resulting in corneal optical irregularities with increasing myopia, irregular astigmatism, corneal opacity and consequential loss of visual acuity. Riboflavin/UV-A corneal cross-linking is a procedure used to biomechanically stabilize the weak cornea in keratoconus and to slow down or halt the clinical progression of this disease. Theranostics is an emerging therapeutic paradigm that enables monitoring of image-guided therapy through the use of a theranostic module that makes use of real-time non-invasive molecular imaging analysis of the tissue being treated to achieve optimal treatment outcomes in the management of disease on a personal basis. The theranostic software module of the C4V CHROMO4VIS™ medical device is able to measure the concentration of riboflavin into the cornea during treatment (i.e., the riboflavin score) and to provide the surgeon with an objective assessment of treatment efficacy (i.e., the theranostic score). The scope of this study is to validate the combined use of the theranostic imaging biomarkers in predicting the flattening of corneal topography Kmax value at 1-year postoperatively. The 1-year follow-up is long enough to provide scientific evidence of the safety and efficacy of the theranostic UV-A medical device in question. A pre-operative examination ensures that every interested and willing participant fulfils the inclusion criteria of this study. Masked post-operative examinations are carried out after 1 week, 1 month, 3 months, 6 months and 12 months. This is a multi-center clinical trial. Eligible participants are stratified with allocation ratio 1:1 into either treatment protocol (epi-off CXL and epi-on CXL) using a computer-generated stratification plan with blocks. Two different blocks are created, which include eyes with Kmax steeper or flatter than 54.0 D to allocate patients with comparable baseline Kmax values in either treatment protocol.

Interventions

DEVICERiboflavin/UV-A corneal cross-linking

Corneal cross-linking procedure is performed using the C4V CHROMO4VIS™ medical device equipped with theranostic software module in all participants. Participants will receive a single dose of the 0.22% riboflavin ophthalmic solution, RitSight™. Application of the riboflavin eye drop is done for 15 minutes for the epi-off CXL treatment and 20 minutes for the epi-on CXL treatment. Estimates of riboflavin concentration into the cornea are monitored by the C4V CHROMO4VIS™ system during the dosing phase of treatment. Once the pre-set dosing phase is completed, the C4V CHROMO4VIS™ system provides the Operator the access to the UV-A light irradiation of the cornea with 5.4 J/cm2 total energy dose (10 mW/cm2 for 9 min.) and 7.00 mm light beam diameter in all participants. Estimates of treatment efficacy by calculation of theranostic score are performed by the C4V CHROMO4VIS™ system during UV-A light irradiation.

Sponsors

University of Roma La Sapienza
CollaboratorOTHER
Regensight
Lead SponsorINDUSTRY

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE

Masking description

Outcome assessor is masked. Statistician is masked. Participant receives stratification to either corneal cross-linking protocol after consent form signature. All participants wear contact lens after treatment until first postoperative eye examination at 1 week, when the corneal epithelium is completely healed.

Intervention model description

One study arm receiving riboflavin/UV-A corneal cross-linking with either standard, epi-off, or transepithelial, epi-on, treatment protocol. Only one eye of each participant is designated as the study eye. If both eyes of a study participant are eligible, the eye with worst CDVA is enrolled and treated.

Eligibility

Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
No

Inclusion criteria

criteria for inclusion in the clinical trial are those currently referred to as the golden standard for the treatment of corneal cross-linking. The criterion to determine progression of keratoconus is based on providing at least one of the following evidences: * at least two Placido disk corneal topography measurements showing at least +1.00 D steepening of the Kmax value in the last year or longer interval period. * at least two manifest refraction measurements showing at least -0.50 D change in spherical equivalent refraction in the last year or longer interval period. * at least two central corneal thickness (CCT) measurements showing at least -10 µm change in in the last year or longer interval period.

Exclusion criteria

* Anterior corneal curvature steeper than 63 D; * Corneal thickness thinner than 400 µm; * Corneal scarring; * Descemetocele; * History of herpetic keratitis; * Concomitant eye diseases; * Inflammatory eye diseases; * Glaucoma; * Cataract; * Nistagmus; * Pregnancy; * Breast feeding.

Design outcomes

Primary

MeasureTime frameDescription
Validation of the Theranostic Scores12 monthsThe aim of this study is to validate the combined use of theranostic imaging biomarkers in predicting the propsensity of corneal corneal cross-linking (CXL) in flattening the Kmax at 1-year. The accuracy and precision (95% CI) of the combined use of the theranostic imaging biomarkers to predict CXL treatment outcome are determined by calculating the percentage of correctly classified eyes and the positive predictive value (PPV) respectively.

Secondary

MeasureTime frameDescription
Corneal Topography12 monthsChange of Maximum Keratometry value of Placido disc corneal topography. The secondary outcome measure of efficacy was assessed by measuring changes of Kmax value (D) from baseline to 12 months postoperatively.
Endothelial Cell Density12 monthsChange of Endothelial Cell Density (ECD) of the cornea. The secondary outcome measure of safety was assessed by measuring change of ECD (cell/mm\^2) from baseline to 12 months postoperatively.

Other

MeasureTime frameDescription
Central Corneal Thickness12 monthsChange of Central Corneal Thickness (CCT). This outcome was assessed by measuring changes of CCT from baseline to 12 months postoperatively.
Manifest Refraction12 monthsChange of Manifest Spherical Equivalent Refraction (MSER). This outcome was assessed by measuring change of MSER (D) from baseline to 12 months postoperatively.
Stratification Groups12 monthsChange of primary and secondary outcome measures in either stratification group (epi-off CXL protocol and epi-on CXL protocol). These exploratory outcome measures included the following assessment: assessmentg of changes of Kmax value (D) at 12-months postoperatively in either stratification group.
Corrected Distance Visual Acuity12 monthsChange of Corrected Distance Visual Acuity (CDVA) measured with ETDRS chart and expressed in LogMAR. This outcome was assessed by measuring changes of CDVA from baseline to 12 months postoperatively. A negative change means improvement in CDVA after treatment.
Uncorrected Distance Visual Acuity12 monthsChange of Uncorrected Distance Visual Acuity (UDVA) measured with ETDRS chart and expressed in LogMAR. This outcome was assessed by measuring changes of UDVA from baseline to 12 months postoperatively. A negative change means improvement in UDVA after treatment.

Countries

Italy

Participant flow

Participants by arm

ArmCount
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module
One study arm receiving riboflavin/UV-A corneal cross-linking with either standard, Epi-OFF, or transepithelial, Epi-ON, treatment protocol. Only one eye of each participant is designated as the study eye. Riboflavin/UV-A corneal cross-linking: Corneal cross-linking procedure is performed using the C4V CHROMO4VIS™ system equipped with theranostic software module in all participants. Participants will receive a single dose of the 0.22% riboflavin ophthalmic solution, RitSight™. Application of the riboflavin eye drop is done for 15 minutes for the EpiOFF CXL treatment and 20 minutes for the EpiON CXL treatment. Estimates of riboflavin concentration into the cornea are monitored by the C4V CHROMO4VIS™ system during the dosing phase of treatment. Once the pre-set dosing phase is completed, the C4V CHROMO4VIS™ system provides the Operator the access to the UV-A irradiation of the cornea with 5.4 J/cm2 total energy dose (10 mW/cm2 for 9 min.) and 7.00 mm light beam diameter in all participants. Estimates of treatment efficacy by calculation of theranostic score are performed by the C4V CHROMO4VIS™ system during UV-A irradiation.
50
Total50

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyLost to Follow-up3

Baseline characteristics

CharacteristicRiboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module
Age, Continuous26 years
STANDARD_DEVIATION 5
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
50 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Medical history
History of allergy/dermatitis
4 participants
Medical history
History of diabetes mellitus
1 participants
Medical history
History of hypothyroidism
3 participants
Medical history
History of systemic lupus erythematosus and ulcerative colitis
1 participants
Medical history
Positive family history of keratoconus
12 participants
Region of Enrollment
Italy
50 participants
Sex: Female, Male
Female
13 Participants
Sex: Female, Male
Male
37 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 50
other
Total, other adverse events
6 / 50
serious
Total, serious adverse events
0 / 50

Outcome results

Primary

Validation of the Theranostic Scores

The aim of this study is to validate the combined use of theranostic imaging biomarkers in predicting the propsensity of corneal corneal cross-linking (CXL) in flattening the Kmax at 1-year. The accuracy and precision (95% CI) of the combined use of the theranostic imaging biomarkers to predict CXL treatment outcome are determined by calculating the percentage of correctly classified eyes and the positive predictive value (PPV) respectively.

Time frame: 12 months

ArmMeasureGroupValue (NUMBER)
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleValidation of the Theranostic ScoresAccuracy91 Percentage
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleValidation of the Theranostic ScoresPrecision95 Percentage
Comparison: Accuracy and precision of the combined use of theranostic imaging biomarkers generated by the UV-A device to predict the propensity of CXL in flattening the Kmax value at 12-months.
Secondary

Corneal Topography

Change of Maximum Keratometry value of Placido disc corneal topography. The secondary outcome measure of efficacy was assessed by measuring changes of Kmax value (D) from baseline to 12 months postoperatively.

Time frame: 12 months

ArmMeasureValue (MEAN)Dispersion
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleCorneal Topography-1.5 dioptersStandard Deviation 1.6
Comparison: Assessment of change of Kmax value at 12-months follow-up visit.p-value: <0.05Wilcoxon (Mann-Whitney)
Secondary

Endothelial Cell Density

Change of Endothelial Cell Density (ECD) of the cornea. The secondary outcome measure of safety was assessed by measuring change of ECD (cell/mm\^2) from baseline to 12 months postoperatively.

Time frame: 12 months

ArmMeasureValue (MEAN)Dispersion
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleEndothelial Cell Density-63 cells/mm^2Standard Deviation 336
Comparison: Assessment of change of ECD value at 12-months follow-up visit.p-value: <0.05Wilcoxon (Mann-Whitney)
Other Pre-specified

Central Corneal Thickness

Change of Central Corneal Thickness (CCT). This outcome was assessed by measuring changes of CCT from baseline to 12 months postoperatively.

Time frame: 12 months

ArmMeasureValue (MEAN)Dispersion
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleCentral Corneal Thickness-5 micrometersStandard Deviation 18
Comparison: Assessment of change of CCT value at 12-months follow-up visit.p-value: <0.05Wilcoxon (Mann-Whitney)
Other Pre-specified

Corrected Distance Visual Acuity

Change of Corrected Distance Visual Acuity (CDVA) measured with ETDRS chart and expressed in LogMAR. This outcome was assessed by measuring changes of CDVA from baseline to 12 months postoperatively. A negative change means improvement in CDVA after treatment.

Time frame: 12 months

ArmMeasureValue (MEAN)Dispersion
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleCorrected Distance Visual Acuity-0.1 LogMARStandard Deviation 0.1
Comparison: Assessment of change of CDVA value at 12-months follow-up visit.p-value: <0.05Wilcoxon (Mann-Whitney)
Other Pre-specified

Manifest Refraction

Change of Manifest Spherical Equivalent Refraction (MSER). This outcome was assessed by measuring change of MSER (D) from baseline to 12 months postoperatively.

Time frame: 12 months

ArmMeasureValue (MEAN)Dispersion
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleManifest Refraction0.2 dioptersStandard Deviation 1.2
Comparison: Assessment of change of MSER value at 12-months follow-up visit.p-value: <0.05Wilcoxon (Mann-Whitney)
Other Pre-specified

Stratification Groups

Change of primary and secondary outcome measures in either stratification group (epi-off CXL protocol and epi-on CXL protocol). These exploratory outcome measures included the following assessment: assessmentg of changes of Kmax value (D) at 12-months postoperatively in either stratification group.

Time frame: 12 months

ArmMeasureValue (MEAN)Dispersion
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleStratification Groups-1.9 dioptersStandard Deviation 2
Epi-on Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleStratification Groups-1.1 dioptersStandard Deviation 1
p-value: <0.05Wilcoxon (Mann-Whitney)
Other Pre-specified

Uncorrected Distance Visual Acuity

Change of Uncorrected Distance Visual Acuity (UDVA) measured with ETDRS chart and expressed in LogMAR. This outcome was assessed by measuring changes of UDVA from baseline to 12 months postoperatively. A negative change means improvement in UDVA after treatment.

Time frame: 12 months

ArmMeasureValue (MEAN)Dispersion
Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software ModuleUncorrected Distance Visual Acuity-0.1 LogMARStandard Deviation 0.1
Comparison: Assessment of change of UDVA value at 12-months follow-up visit.p-value: <0.05Wilcoxon (Mann-Whitney)

Source: ClinicalTrials.gov · Data processed: Feb 10, 2026