Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT04945850 |
| Other study ID # |
100800 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
June 16, 2021 |
| Est. completion date |
March 14, 2022 |
Study information
| Verified date |
March 2022 |
| Source |
Vanderbilt University Medical Center |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational [Patient Registry]
|
Clinical Trial Summary
Several common viruses thrive and persist in intraocular fluid due to ocular immune
privilege. Immune privilege is maintained by lack of lymphatic tissue, a strong blood ocular
barrier, and regulation of the systemic immune response via immunosuppressive factors such as
TGF-B and processes like anterior chamber associated immune deviation. Notable viruses that
benefit from ocular immune sequestration include DNA viruses such as Herpes simplex virus,
Varicella Zoster, Cytomegalovirus and RNA viruses like Ebola and Rubella.In light of the
global 2019 Severe acute respiratory syndrome coronavirus-2 virus (SARS CoV-2 or commonly
COVID-19) pandemic, there has been growing interest on COVID-19's long term effects on the
ocular system. Ocular symptoms at the time of diagnosis and during illness have been reported
previously. The most commonly reported are epiphora, chemosis, and conjunctivitis. Less
common were findings of retinal hemorrhages and retinal ischemic changes. Recent literature
has demonstrated its presence in ocular fluid such as tears and the aqueous humor, but
whether this is sustained for an extended period of time has yet to be determined. Long term
effects of covid on the neurological system are being identified - large vessel ischemic
strokes, cerebral hemorrhages, cranial nerve palsies, and memory loss in young adults are
being reported. The persistence of COVID 19 in the intraocular fluid several months after
covid infection has not been studied previously.
Description:
Animal Studies and Previous Human Studies
Other coronavirus murine and feline models have shown ocular involvement. In Robbins et al
experiment, mice underwent intracameral and intravitreal injections with murine coronavirus.
Within 3 days, those with injections into the AC demonstrated a variety of findings such as
keratitis and anterior uveitis; whereas those who underwent intravitreal injection had
multilayered retinal lesions with RPE scarring and retinal atrophy. CNS disease and/or death
occurred in a third of those from intravitreal injections. Viral antigens have been isolated
from these mice but there is evidence immune cells and pro-inflammatory factors also
contribute to the retinopathy findings. This murine model, known as Experimental CoV
Retinopathy, has been used to examine host immune response that lead to retinal damage. Cats
infected with feline infectious peritonitis virus, a feline coronavirus, manifested with
conjunctivitis, pyogranulomatous anterior uveitis, retinal vasculitis, choroiditis and
retinal detachment. Over 90% of the cats had antigen detected in the conjunctiva.
Viruses such as VZV, HSV, and CMV and parasites like Toxoplasmosis have been isolated from
the intraocular fluid of human eyes using polymerase chain reaction (PCR), despite having
normal or negative serum titers.
Enrollment/Randomization
Those who meet inclusion criteria will be provided an opportunity to participate in study.
They will provide written informed consent in accordance with the HIPAA regulations and
Vanderbilt IRB approval.
Study Procedures
- Patients selected for study:
80 total patients
20 patients undergoing ocular surgery who are COVID negative will be included as control
patients and undergo the same procedures 60 patients undergoing ocular surgery with
previous COVID infection will be stratified into three groups by time since diagnoses:
3, 6, 12 months ~ 20 patients per group.
- All patients will get a vitreous tap from operative eye 0.1-0.2 ml fluid. This
fresh sample will be tubed to the lab using a unique marked label. This will be
performed after the trocar is placed
- At the end of surgery, the BSS bag will be tubed to the lab using the same label.
- Informed consent will be obtained during pre-operative clinic visit
- Samples will get a special-colored label and tubed to Dr Schmitz and Dr. Maris lab from
the OR
Laboratory analyses
VUMC MIDL Lab Testing Protocol:
• Specimens: 100-200ul dry taps of vitreous fluid will be delivered to the VUMC MIDL lab and
frozen (-80C) until nucleic acid is extracted. 1L bags of BSS saline containing ocular fluid
will be delivered to the VUMC MIDL lab and aliquoted into 3 10ml falcon tubes and then frozen
(-80C) until nucleic acid is extracted.
Nucleic acid extraction:
• Specimens will have total RNA & DNA extracted on the easyMAG, EMAG, or EZ1 automated
nucleic acid extraction platforms.
Real time RT-PCR:
• RNA present in nucleic acid extracts will be reverse transcribed into cDNA. Target cDNA
will be amplified by PCR and target fluorescence emission will be measured and detected in
real time. Targets include the N1 & N2 regions of the nucleocapsid gene of SARS-CoV-2, and an
internal control to monitor for adequate nucleic acid extraction and absence of PCR
inhibitors: human RNase P (RP). Target Ct values will be recorded from detected samples.
Next Generation Sequencing (NGS):
- Illumina: Nucleic acid extracts will undergo targeted SARS-CoV-2 whole genome
amplification by tiling PCR. Amplicons will undergo DNA library preparation, barcoding,
and QC. DNA libraries will be inoculated onto MiSeq flow cells and sequenced. Reads will
be outputted as FASTQ files.
- MinION: Total nucleic acid extracts will undergo DNA library preparation, barcoding, and
QC. DNA libraries will be inoculated onto MinION Mk1C & Flongle flow cells for
metagenomic deep sequencing. Reads and associated quality data will be outputted as
FASTQ files.
Risks
The study procedures involve minimal risk as they are performed in an eye that is undergoing
an elective scheduled operative procedure for medical reasons. The safe and sterile procedure
greatly decreases the risk.
Reporting of Adverse Events or Unanticipated Problems involving Risk to Participants or
Others
Any adverse events will be reported to the Vanderbilt Eye Institute, and VUMC IRB per policy
and procedure. These will be submitted within one week of occurrence.
Study Withdrawal/Discontinuation
VUMC IRB will be notified of study withdrawal and discontinuation. We anticipate the study to
last approximately 1 year.
Data analysis:
Ct values from RT-PCR detected samples will be compared and correlated with clinical data.
SARS-CoV-2 sequences from Illumina and MinION NGS platforms will be analyzed for variants and
correlated with clinical data. non-SARS-CoV-2 microbial sequences will be analyzed and
identified to the microbial species level. The ocular fluid 'microbiome' will be compared
across samples and correlated with clinical data.
Privacy/Confidentiality Issues
Patient information will be de-identified and uploaded to REDCAP survey to ensure
confidentiality and privacy.
Follow-up and Record Retention
The duration is expected to be one year. The data will be retained for six months following
closure of the study. This will be destroyed afterward.
