Kerasave

{0}------------------------------------------------ ## DE NOVO CLASSIFICATION REQUEST FOR KERASAVE #### REGULATORY INFORMATION FDA identifies this generic type of device as: Corneal storage medium with preservatives including antifungals. Corneal storage medium with preservatives including antifungals is a device that is used to temporarily preserve human cornea tissue between harvesting and implantation. NEW REGULATION NUMBER: 21 CFR 886.4320 CLASSIFICATION: Class II PRODUCT CODE: QCW #### BACKGROUND DEVICE NAME: Kerasave SUBMISSION NUMBER: DEN200063 DATE DE NOVO RECEIVED: November 10, 2020 #### SPONSOR INFORMATION: AL.CHI.MI.A. S.r.l. Viale Austria 14 Ponte San Nicolo, Province of Padua 35020 ITALY #### INDICATIONS FOR USE Kerasave is indicated for storage of human corneas at 2-8°C for up to 14 days. It is intended for prescription (Rx) use by physicians or highly skilled personnel, such as Eye Bank operators. #### LIMITATIONS The sale, distribution, and use of Kerasave are restricted to prescription use in accordance with 21 CFR 801.109. Prior to distribution for surgical use, the cornea should be evaluated for suitable use as there may be reduced corneal clarity during storage due to the addition of Amphotericin B. {1}------------------------------------------------ # PLEASE REFER TO THE LABELING FOR A MORE COMPLETE LIST OF WARNINGS, PRECAUTIONS, AND CONTRAINDICATIONS. ## DEVICE DESCRIPTION Kerasave is made of a buffered corneal storage medium, which provides basic nutrients for cell maintenance during storage of donor corneas at 2-8°C for up to 14 days, at physiological pH. The device also includes antimicrobial agents. The antibiotics are dissolved in the solution and an antifungal agent is formulated as a tablet for stability reason and constitutes integral part of the device; it shall be dissolved in the medium prior to use. The product specifications and ingredients for the Kerasave are presented in Table 2, respectively, below. | Parameter | Product | |---------------------------|-------------------------------------------| | Form | Liquid | | Appearance | Clear orange-red solution | | Volume/Weight | 20 mL | | Sterilization | Filtration | | Contents | 12 vials and 12 tablets of Amphotericin B | | Storage temperature | 2-8°C | | Shelf-life | 24 months | | Temperature of actual use | 2-8 °C | | Use-life | 14 days | | Number of uses | Single-use | #### Table 1: Kerasave product summary {2}------------------------------------------------ | Ingredient | Category | Function | |-------------------------------------------------------------------------------------|---------------|------------------------------------------------------------------------------------------------------| | (b)(4) and (b)(4) salt solution (including amino acids, vitamins, (b)(4) and (b)(4) | Base medium | Provides basic nutrients for cell maintenance, maintains pH, and a color indicator for pH indication | | Sodium bicarbonate | Buffer | Maintains pH | | Gentamicin sulfate | Antibiotic | Reduces bacterial growth | | Streptomycin sulfate | Antibiotic | Reduces bacterial growth | | Amphotericin B | Antifungal | Reduces Fungal Growth | | Dextran (b)(4) | Osmotic agent | Prevents swelling, preserves corneal thickness | | Sodium pyruvate | ATP precursor | Provides energy for pumping function | ## Table 2: Kerasave ingredients and their functions ## SUMMARY OF NONCLINICAL/BENCH STUDIES ## BIOCOMPATIBILITY Kerasave is a surface device with prolonged (> h to 30 days) contact with breached/compromised surface. The biocompatibility assessment summarized below in Table 3 was conducted in accordance with FDA's Biocompatibility Guidance Document titled "Use of International Standard ISO 10993-1, "Biological evaluation of medical devices - Part 1: Evaluation and testing within a risk management process", as well as other relevant parts of standard ISO 10993- Biological evaluation of medical devices. This assessment demonstrated that the device is biocompatible for its intended use. ## Table 3: Summary of Biocompatibility Assessment | Biocompatibility assessment | Assessment outcome | |-------------------------------------------------------------------------------------|--------------------| | Cytotoxicity (MEM extraction method) (ISO 10993-5) | Non-cytotoxic | | Sensitization (Guinea pig maximization test) (ISO 10993-10) | Non-sensitizer | | Ocular irritation (ISO 10993-10) | Non-irritant | | Acute systemic toxicity (FDA Biocompatibility Guidance) | Non-toxic | | Material mediated pyrogenicity (FDA Biocompatibility<br>Guidance) | Non-pyrogenic | | Subacute/Subchronic systemic toxicity (FDA<br>Biocompatibility Guidance) | Non-toxic | | Biocompatibility Assessment of Primary Packaging (FDA<br>Biocompatibility Guidance) | Biocompatible | {3}------------------------------------------------ # CHEMICAL CHARACTERIZATION Analysis of critical properties of Amphotericin B through chemical characterization were (D)(4) performed through multiple assessments. Identification by indicated that the Amphotericin B in Kerasave is the same as the TOTAL reference Amphotericin B CRS (Chemical Reference Substance). Further testing of the Amphotericin B tablet included an impurity profile that met limits based on US Pharmacopeia (UP) and European Pharmacopoeia; a heavy metals tests that met the acceptance criterion of @pm, and a light degradation assessment which demonstrated that the Amphotericin B concentration was above 11% after Thours of light exposure and indicated Amphotericin B was stable after hours of light exposure. Testing performed after dissolution of the tablet in solution indicated that there was a uniform distribution of the Amphotericin B and that the osmolality and pH stayed within acceptance limits 14 days after dissolving amphotericin B tablet in the solution, ### SHELF-LIFE/STERILITY Device sterility is achieved using multiple methods of sterilization, including filter sterilization of the corneal storage medium, a combination of dry heat and gamma irradiation of the device primary packaging, and gamma irradiation of the Amphotericin B tablets. The dry heat and gamma irradiation sterilization methods were demonstrated to achieve a Sterility Assurance Level of 106 (e.g., a reduction of at least 106 microorganisms). The filter sterilization method was validated to reproducibly remove viable microorganisms from the aseptic manufacturing process. Bacterial endotoxin. testing demonstrated levels below recommended limits. A shelf-life of 24 months has been established for Kerasave corneal storage media when stored at the recommended storage temperature of 2-8℃ in its primary packaging. A shelf-life of months has been established for Amphotericin B tablets when stored at the recommended storage temperature of 4℃ in its primary packaging. These claims are supported by demonstration of Kerasave corneal storage media and Amphotericin B tablet sterility and stability in both real-time and accelerated aging studies, as well as after short term storage at high temperatures. Relevant standards followed include: Sterilizing Filtration of Liquids (PDA TR 26-2008-). Standard Test Method for Determining Bacterial Retention of Membrane Filters Utilized for Liquid Filtration (ASTM F838)-, Sterilization of health care products (ISO 11137-1 and ISO 11137-2, and ISO 20857). Bacterial Endotoxins (USP<85>). ## PERFORMANCE TESTING - BENCH The performance characteristics of Kerasave were assessed to ensure that the cornea was preserved while in storage. The assessment for the preservation of the cornea included the viability of the endothelial cell layer, corneal clarity, and cornea central thickness. ### CORNEAL ENDOTHELIAL CELL LAYER PRESERVATION The performance characteristics of Kerasave were assessed in comparison with Optisol-GS, a US FDA-cleared corneal storage medium as control in preserving the corneal endothelial cell layer using a Konan specular microscope. The specular microscopy outcomes measured were: {4}------------------------------------------------ - Endothelial cell density (ECD) . - . Endothelial cell morphology (pleomorphism): Hexagonality (HEX) - Endothelial cell morphology (polymegathism): Coefficient of variation (%CV) . Twenty-seven (27) paired donor corneas were included in the study. For each paired corneas, one comea was stored in Kerasave and the contralateral cornea in Optisol-GS. Tissue and media assignments were performed randomly. The storage was performed at 2-8°C for 14 days and each cornea was tested at Day 1 and Day 14. The study demonstrated that, using a mon-inferiority margin, the corneas stored in Kerasave were non-inferior to those stored in Optisol-GS at Day 14 in terms of ECD (Table 4) and HEX (Table 5). The study failed to statistically clear the 10% noninferiority margin between Kerasave and Optisol-GS at Day 14 in terms of %CV (Table 6). However, an exploratory analysis that excluded an outlier datapoint (CV%=DM) for Kerasave (identified as a protocol deviation), showed that Kerasave was non-inferior to the Optisol-GS in terms of Coefficient of variation (Table 7). ## Table 4: Endothelial Cell Density (ECD) Results Obtained in Corneas Stored in Kerasave or Optisol-Gs at Day 1 and Day 14 | | Kerasave | | Optisol-GS | | |---------------------------------------------------------------------------------------------|-----------|------------|------------|------------| | | ECD Day 1 | ECD Day 14 | ECD Day 1 | ECD Day 14 | | Mean (cells/mm) | | | | (b)(4) | | SD (cells/mm) | | | | | | Median (cells/mm) | | | | | | Minimum (cells/mm) | | | | | | Maximum(cells/mm) | | | | | | Coefficient of variation (%) | | | | | | d, non-inferiority limit<br>(10% of the mean ECD in Optisol-GS<br>day 14) | | | | | | The null hypothesis<br>µs: the mean Optisol-GS treatment<br>µe: the mean Kerasave treatment | | | | | | Alternative hypothesis | | | | | | Statistical analysis and conclusion | | | | | {5}------------------------------------------------ # Table 5: Pleomorphism (hexagonality, HEX) results obtained in corneas stored in Kerasave or Optisol-Gs at Day 1 and Day 14 of storage | | Kerasave | | Optisol-<br>GS | | |-----------------------------------------------------------------------------------------------|--------------|---------------|----------------|---------------| | | HEX<br>Day 1 | HEX<br>Day 14 | HEX<br>Day 1 | HEX<br>Day 14 | | Mean | | (b)(4) | | | | SD | | | | | | Median | | | | | | Minimum | | | | | | Maximum | | | | | | Coefficient of variation<br>(%) | | | | | | d, non-inferiority limit<br>(10% of the mean HEX<br>in Optisol- GS day 14) | | | | | | Null hypothesis<br>μs: the mean Optisol-GS<br>treatment<br>μe: the mean Kerasave<br>treatment | | | | | | Alternative hypothesis | | | | | | Statistical analysis and<br>conclusion | | | | | {6}------------------------------------------------ ## Table 6: Statistical evaluation of polymegathism (%CV) results based on pre-specified analysis obtained in corneas stored in Kerasave or Optisol-Gs at Day 1 and Day 14 of storage | | Kerasave | | Optisol-GS | | |-------------------------------------------------------------------------------------------------------------------------------------------|----------|--------|------------|--------| | | Day 1 | Day 14 | Day 1 | Day 14 | | Mean | | | (b)(4) | | | SD | | | | | | Median | | | | | | Minimum | | | | | | Maximum | | | | | | Coefficient of<br>variation | | | | | | d, non-inferiority limit<br>(10% of the mean CV% in Optisol-GS<br>day 14) | | | | | | Null hypothesis<br>$ μs $ : the mean Optisol-GS treatment<br>$ μe $ : the mean Kerasave treatment | | | | | | Alternative hypothesis | | | | | | Statistical analysis and conclusion | | | | | ## Table 7: Exploratory Analysis of polymegathism (%CV) results obtained in corneas stored in Kerasave or Optisol-Gs at Day 1 and Day 14 of storage | | Kerasave | | Optisol-GS | | |----------------------------------------------------------------------------------------------|----------|--------|------------|--------| | | Day 1 | Day 14 | Day 1 | Day 14 | | Mean | | (b)(4) | | | | SD | | | | | | Median | | | | | | Minimum | | | | | | Maximum | | | | | | Coefficient of variation | | | | | | d, non-inferiority limit<br>(10% of the mean CV% in Optisol- GS day 14) | | | | | | Exploratory analysis<br>μs: the mean Optisol-GS treatment<br>μe: the mean Kerasave treatment | | | | | # EVALUATION OF PERFORMANCE CHARACTERISTICS ON CORNEA Corneal clarity and central corneal thickness (CCT) were evaluated at Day 1 and Day 14. The 27 paired donor corneas used in the specular microscopy measurements were also used to determine the CCT and corneal clarity through optical coherence {7}------------------------------------------------ tomography and slit lamp examination, respectively. The results demonstrated that the CCT changes were similar between the Kerasave and Optisol-GS arms and had no statistical difference (Table 8). # Table 8: Statistical evaluation of Corneal central thickness (CCT) by OCT obtained in corneas stored in Kerasave or Optisol-GS at Day 1 and Day 14 of storage | | Kerasave | | | Optisol-GS | | | |--------------------------------------------|--------------|---------------|---------------------------------|--------------|---------------|---------------------------------| | | CCT<br>Day 1 | CCT<br>Day 14 | Change in CCT<br>(Day14 - Dayl) | CCT<br>Day 1 | CCT<br>Day 14 | Change in CCT<br>(Day14 - Dayl) | | Mean (µm) | | | (b)(4) | | | | | SD (µm) | | | | | | | | Median (µm) | | | | | | | | Minimum (µm) | | | | | | | | Maximum (µm) | | | | | | | | Coefficient of variation(%) | | | | | | | | <i>p</i> value (Kerasave<br>vs Optisol-GS) | | | | | | | In the assessment for corneal clarity, a statistical difference was not observed for the clarity scores on the Day 14 between Kerasave and the comparator arm, Optisol-GS (Table 9). It should be noted that Kerasave had 7 out of the 27 corneas that progressed from a score of '1' (mild) on Day 1 to a score of '2' (moderate) on Day 14 demonstrating an increase in opacity. Whereas the control arm had 2 out of 27 corneas that had increased opacity from Day 1 to Day 14. Additionally, increased edema and fold/striae were observed in the corneas that progressed. # Table 9: Statistical evaluation of corneal transparency scores obtained in corneas stored in Kerasave or Optisol- GS at Day 1 and Day 14 of storage | | Transparency score<br>Kerasave | | Transparency score<br>Optisol-GS | | |------------------------------------------------|--------------------------------|--------|----------------------------------|--------| | | Day 1 | Day 14 | Day 1 | Day 14 | | Median | | (b)(4) | | | | Minimum | | | | | | Maximum | | | | | | <i>p</i> value1<br>(Kerasave vs<br>Optisol-GS) | | | | | 1Day 1 (p=1.0000, Mann-Whitney test) and Day 14 (p=0.1651, Mann-Whitney test) ## ANTIMICROBIAL EVALUATION An analysis of antimicrobial presence and activity were provided. FDA determined that the concentrations of streptomycin, gentamicin, and Amphotericin B in the Kerasave device were unlikely to contribute to antimicrobial resistance emergence, or the spread of resistant microorganisms. {8}------------------------------------------------ Ex-vivo testing and preservative testing were provided to evaluate effectiveness of the instructions for use in reducing antimicrobial presence prior to implantation to reduce unnecessary exposure, as well as the antimicrobial effectiveness of the antimicrobial components of the device, respectively. ## EX VIVO TESTING Assessment of Amphotericin B accumulation on the cornea grafts was nerformed to determine the residual concentration of the antifungal after storage. [[b](4] corneal grafts (n=0) were stored in Kerasave device at 2-8°C for 14 days. The grafts (with or without rinsing in @mL of of to blows) were (b)s) ======================================================================================================================================================================== and evaluated (CD)10) by I for the presence of Amphotericin B. Amphotericin B was below detection limit in rinsed corneas and between mail - mg/cornea in corneas that were not rinsed. # PRESERVATIVE TESTING Kerasave with streptomycin and gentamicin (antibacterials) and Amphotericin B (antifungal) were tested at appropriate concentrations in the final solution. Testing was conducted to evaluate the microbial log reduction of laboratory strains, specifically | specifically | | and | | |-----------------------------------------------------------------------------------------|-------------------------------------------------------------------------------|-----|--| | | (b)(4) after incubation in Kerasave. Testing was performed at (b)(4) (e.g., t | | | | temperature range for product storage), and conducted in accordance with standard | | | | | ISO 18259 (Contact lens care products). | (b)(4) in the device arm was | | | | compared to microbial growth the control arm, which involved | (b)(4) The results indicate | | | | that the combination of streptomycin and gentamicin in Kerasave inhibited the | | | | | growth of all | (b)(4) tested in comparison to the respective | | | | controls and reduced the number of | (b)(4) with known | | | | susceptibility. With the addition of Amphotericin B to the storage solution, the (b)(4) | | | | | (b)(4) population was reduced by (b)(4) (+/- SE), while the spore-forming | | | | | filamentous fungi (Fusarium sp.) population was reduced by -log (+/- SE). These | | | | | results demonstrate that the device adequately inhibited the growth of laboratory | | | | ## LABELING Device labeling satisfies the requirements of 21 CFR & 801.109 for prescription devices. The device labeling provides product description, Indications for Use, and instructions for how to use the device by the end user. The labeling also provides a summary of the cornea viability after storage. The labeling includes warnings and precautions describing limitations and risks of the device. # RISKS TO HEALTH The table below identifies the risks to health that may be associated with use of corneal storage medium with preservatives including antifungals and the measures necessary to mitigate these risks. {9}------------------------------------------------ | Identified Risks to Health | Mitigation Measures | |----------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------| | Infection | Sterilization validation<br>Non-clinical performance testing<br>Labeling<br>Shelf life testing | | Adverse tissue reaction | Biocompatibility evaluation<br>Non-clinical performance testing | | Antimicrobial resistance | Antimicrobial resistance analysis<br>Non-clinical performance testing<br>Labeling | | Worsening prognosis that may need recurring<br>or more invasive surgery due to damage to<br>cornea tissue while in storage | Non-clinical performance testing<br>Labeling | ### Table 10: Identified Risks to Health and Mitigation Measures ### SPECIAL CONTROLS In combination with the general controls of the FD&C Act, the corneal storage medium with preservatives including antifungals is subject to the following special controls: - (1) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use. - (i) The following performance characteristics of the cornea following storage in the device must be demonstrated: - (A) Endothelial cell density; - Endothelial cell morphology; (B) - (C) Corneal transparency; and - (D) Central corneal thickness. - Antimicrobial activity of the device must be demonstrated at the initial and (ii) maximum labeled storage time. - (iii) Characterization of all preservatives, including antifungals, must include the following: - (A) Characterization of impurities, heavy metal analysis, concentration, and dissolution; and - Chemical activity of all preservatives over the labeled use life of the (B) device. {10}------------------------------------------------ - (2) Performance data must demonstrate the sterility of the device. - The device must be demonstrated to be biocompatible and non-pyrogenic. (3) - (4) Performance data must support the claimed shelf life by demonstrating continued sterility, controlled bioburden, package integrity, and device functionality over the intended shelf life. - (5) The device and each of its components (e.g., antifungal, antibiotic, medium) must be demonstrated to be compatible with their respective commercial container closure system/packaging. - (6) An analysis must be provided that identifies and evaluates any contribution to the development and spread of antimicrobial resistance. - (7) Labeling must include the following instructions: - (i) Rinsing of cornea prior to transplantation; and - (ii) Complete dissolution of all preservatives. ## BENEFIT-RISK DETERMINATION The risks of the device are based on the non-clinical performance testing data collected. The data demonstrated that corneal clarity decreased with increased edema and folds/striae in some of the corneas stored in the device for 14 days. Device labeling will help ensure that the end users clearly understand the device description, indications, contraindications, precautions, warnings, and instructions for use. Specifically, the device labeling informs the end user to check the suitability of the cornea prior to distribution. The probable benefits of the device are based on the non-clinical performance testing data collected. The non-clinical study demonstrated inhibition in the growth of microbials in the presence of preservatives, including an antifungal in the device. The endothelial cell layer was preserved in the corneas stored in the device for 14 days. Although it is unknown whether reduced corneal clarity may occur after transplantation, the overall probable benefits of limiting infection of the cornea tissue stored in the device that includes an antifungal agent to minimize microbial growth outweighs the probable risks of decreased corneal clarity. ### Pediatric Extrapolation In this De Novo request, existing clinical data were not leveraged to support the use of the device in a pediatric patient population. ### Patient Perspectives This submission did not include specific information on patient perspectives for this device. {11}------------------------------------------------ ## BENEFIT/RISK CONCLUSION In conclusion, given the available information above, for the following indication statement: Kerasave is indicated for storage of human corneas at 2-8°C for up to 14 days. It is intended for prescription (Rx) use by physicians or highly skilled personnel, such as Eye Bank operators. The probable benefits outweigh the probable risks for the Kerasave device. The device provides benefits, and the risks can be mitigated by the use of general controls and the identified special controls. ## CONCLUSION The De Novo request for the Kerasave is granted and the device is classified as follows: Product Code: QCW Device Type: Corneal storage medium with preservatives including antifungals Regulation Number: 21 CFR 886.4320 Class: II