Clinical trial NCT01604135: Collagen Crosslinking for Keratoconus - a Randomized Controlled Clinical Trial
Official title: Collagen Crosslinking for Keratoconus - a Randomized Controlled Clinical Trial
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: PHASE3
Conditions: Keratoconus
Keywords: Collagen crosslinking
Keratoconus
Lead sponsor: Sahlgrenska University Hospital
Sponsor class: OTHER
Collaborators: name: Göteborg University
First posted: 2012-05-23
Enrollment: 36
Sex: ALL
Minimum age (years): 18
Maximum age (years): 30
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to determine whether corneal collagen crosslinking is effective in the treatment of progressive keratoconus.

Detailed description: Keratoconus is a noninflammatory, asymmetrical, progressive corneal ectasia caused by biomechanical instability of the corneal stroma. Treatment modalities are primarily glasses or contact lenses. It has been estimated that one out of five patients will progress to such an extent that a corneal transplant is necessary to regain useful vision.

Corneal collagen crosslinking (CXL) is a treatment modality that intends to halt progression of keratoconus. This study investigates the efficacy av CXL in stabilizing the cornea in keratoconus by means of a randomized controlled clinical trial.

Participants are eligible for inclusion if progressive keratoconus is confirmed and the inclusion criteria are met. Follow-up after inclusion is at 1 week (treatment group), 1, 3, 6 and 12 months. Pre- and post-inclusion examinations include measurement of uncorrected distance visual acuity (UCDVA), best spectacle corrected distance visual acuity (BSCDVA), Scheimpflug-topography and slitlamp examination.

Eligibility criteria: Inclusion Criteria:

* Keratoconus diagnosis determined clinically and topographically (KISA%- index)
* Significant progression is defined as change (increase) of Kmax by at least

  1D from baseline at 6 months and/or change (increase) of Sim-K-ast by at least 1D from baseline at 6 months. Kmax is defined as the steepest radius of curvature (either the maximum simulated K-reading or the maximum K-reading in the 3-mm zone or the 5-mm zone) of the anterior corneal surface that progressed the most during 6 months observation
* Ability to stop contact lens (rigid and soft) wear at least two weeks prior to next exam
* Signed written informed consent

Exclusion Criteria:

* Age \< 18 years
* Pregnancy
* Breast feeding
* History of corneal surgery
* History of ocular herpes simplex infection
* Minimal corneal thickness \< 300 micrometers
* Recurrent corneal erosions
* Other corneal (e g endothelial) or conjunktival diseases
* Neurodermatitis
* Severe forms av atopic disease
* Collagenoses, autoimmune or other systemic disease
* Systemic treatment with high doses of steroids
* Severe scarring och striae of the cornea

Relative exclusion criteria:

* Kmax \> 58D
* Minimal corneal thickness \< 400 micrometers (a modified CXL-treatment will be used swelling the cornea before UV-illumination treatment).

Primary outcomes:
measure: Kmax
timeFrame: 12 months
Secondary outcomes:
measure: Sim-K-astigmatism
timeFrame: 12 months
measure: MRSE
timeFrame: 12 months
measure: UCDVA
timeFrame: 12 months
measure: BSCDVA
timeFrame: 12 months
Other outcomes:
Locations:
city: Mölndal
country: Sweden
facility: Department of Ophthalmology, Sahlgrenska University Hospital
state: Västra Götalandsregionen
Study officials:
affiliation: Sahlgrenska University Hospital
name: Madeleine Zetterberg, MD, PhD
role: STUDY_CHAIR
affiliation: Sahlgrenska University Hospital
name: Margareta Claesson, MD, PhD
role: STUDY_DIRECTOR
References:
citation: Hersh PS, Greenstein SA, Fry KL. Corneal collagen crosslinking for keratoconus and corneal ectasia: One-year results. J Cataract Refract Surg. 2011 Jan;37(1):149-60. doi: 10.1016/j.jcrs.2010.07.030.
citation: Greenstein SA, Fry KL, Hersh PS. Corneal topography indices after corneal collagen crosslinking for keratoconus and corneal ectasia: one-year results. J Cataract Refract Surg. 2011 Jul;37(7):1282-90. doi: 10.1016/j.jcrs.2011.01.029.
citation: Wollensak G, Spoerl E, Seiler T. Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. Am J Ophthalmol. 2003 May;135(5):620-7. doi: 10.1016/s0002-9394(02)02220-1.
citation: Wittig-Silva C, Chan E, Islam FM, Wu T, Whiting M, Snibson GR. A randomized, controlled trial of corneal collagen cross-linking in progressive keratoconus: three-year results. Ophthalmology. 2014 Apr;121(4):812-21. doi: 10.1016/j.ophtha.2013.10.028. Epub 2014 Jan 6.