Keratoconus
Conditions
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
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
Study design
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
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
| Measure | Time frame | Description |
|---|---|---|
| Validation of the Theranostic Scores | 12 months | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Corneal Topography | 12 months | 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. |
| Endothelial Cell Density | 12 months | 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. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Central Corneal Thickness | 12 months | Change of Central Corneal Thickness (CCT). This outcome was assessed by measuring changes of CCT from baseline to 12 months postoperatively. |
| Manifest Refraction | 12 months | Change of Manifest Spherical Equivalent Refraction (MSER). This outcome was assessed by measuring change of MSER (D) from baseline to 12 months postoperatively. |
| Stratification Groups | 12 months | 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. |
| Corrected Distance Visual Acuity | 12 months | 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. |
| Uncorrected Distance Visual Acuity | 12 months | 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. |
Countries
Italy
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| 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 |
| Total | 50 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | Lost to Follow-up | 3 |
Baseline characteristics
| Characteristic | Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module |
|---|---|
| Age, Continuous | 26 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 type | EG000 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
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
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Validation of the Theranostic Scores | Accuracy | 91 Percentage |
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Validation of the Theranostic Scores | Precision | 95 Percentage |
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
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Corneal Topography | -1.5 diopters | Standard Deviation 1.6 |
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
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Endothelial Cell Density | -63 cells/mm^2 | Standard Deviation 336 |
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
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Central Corneal Thickness | -5 micrometers | Standard Deviation 18 |
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
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Corrected Distance Visual Acuity | -0.1 LogMAR | Standard Deviation 0.1 |
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
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Manifest Refraction | 0.2 diopters | Standard Deviation 1.2 |
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
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Stratification Groups | -1.9 diopters | Standard Deviation 2 |
| Epi-on Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Stratification Groups | -1.1 diopters | Standard Deviation 1 |
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
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Riboflavin/UV-A Corneal Cross-linking Monitored by Theranostic Software Module | Uncorrected Distance Visual Acuity | -0.1 LogMAR | Standard Deviation 0.1 |