1. Antioxidant Studies: Retinal Disease in Patients with the Smith-Lemli-Opitz Syndrome (SLOS)
Ellen Roy Elias, MD, FAAP. FACMG
Professor, Pediatrics and Genetics
Children’s Hospital Colorado

2. Retinal studies in SLOS
Historical reason for interest:
While still in Boston, one of my patients with severe SLOS went blind as a teenager and developed severe pigmentary retinopathy, loss of night vision, and markedly abnormal ERG
Additional Boston SLOS patients were tested and most found to have abnormal rod cell function Elias ER et al, Arch Ophthalmol 2003, 121(12):

3. Animal Model of the SLOS Retina
In Vitro Studies done by Steve Fleisler, in the rat SLO model
SLO model: rats treated with AY9944, which causes 7-DHC accumulation
AY9944-treated rats exposed to light showed massive loss of photoreceptor cells, and dysfunction of rods and cones on ERG studies (similar findings to that seen in SLO humans). The abnormal retina showed an accumulation of oxysterols, toxic compounds made by the oxidation of 7-DHC
The damage caused by light was preventable by pretreatment with the antioxidant, DMTU

4. Intravitreal Oxysterol Injection Produces Panretinal Degeneration
WARNING!! DON’T TRY THIS AT HOME !!
Xu L, Liu W, Porter NA, Sheflin LG, Young JE, & Fliesler SJ (ARVO 2011)

5. The SLOS Protocol at Children’s Hospital Colorado
History of Colorado Protocol:
Boston protocol brought to CO in 2001, using Cholesterol suspension in Soy oil
2008 introduction of vitamin/antioxidant preparation called AquADEKS in addition to cholesterol. AquADEKS is an antioxidant medicine which has been proven safe to use in pediatric patients.
Patients followed by serial Ophthalmology exams/electroretinograms (ERG’s)

6. SLOS Protocol at Childrens Hospital Colorado
The protocol is approved by COMIRB, protocol #
The protocol was partially supported by the CTRC, as well as a private philanthropic support
Up to 100 patients can be enrolled (currently 29)
Cholesterol is compounded and shipped by the Ward Rd Pharmacy, and billed to the patient’s insurance
The AquADEKS has been provided by the pharmacy at Children’s Hospital Colorado
Procedures including ERG/ Eye eval and some labs billed to insurance

7. SLOS Treatment Protocol
Cholesterol Suspension 200 mg/ml (formerly on IND # 101,562) made from pharmaceutical grade Cholesterol in Soy Oil, used at doses ranging from mg/kg/day divided three times a day
Antioxidant Medication (AQUADEKS) added since It comes as both a liquid, a chewable tablet and a capsule – dosage based on age and size of patient

8. SLOS Treatment Protocol
AquADEKS is a preparation containing vitamins and minerals with antioxidant properties, chosen as it has been proven safe to use in children.
The following substances are found in AquADEKS:
Vitamins A, C, E ( also vitamins B, D and K)
b-carotene
Coenzyme Q10
Zinc
Selenium

9. Antioxidant Treatment in SLOS Patients
Effects on the retina in SLOS:
Earlier studies had shown two retinal issues:
Pigmentary retinopathy
Abnormal retinal function on ERG consisting of reduced amplitude of the wave, and an increased latency time; ie. it took a greater amount of light energy a longer period of time to produce a retinal response

10. The Retina and ERG waves

12. Results Mild patients: (sterol ratio < 3.5)
N=7 patients with at least 1 ERG
ERG results:
Mild patients showed increased implicit times in rods and cones
Rods were affected more than cones:
rods showed mild/moderate decrease in amplitude
cones showed normal to mild changes.
3 patients with serial studies, all showed improved amplitudes and decreased implicit times.
EUA studies:
2 patients showed mild pigmentary retinopathy which improved on follow-up testing
No progression of RPE seen in any patient
No optic nerve abnormalities seen
(1 patient died of unrelated issues, 2 lost to follow-up, 1 recently enrolled)

13. Results Moderate patients
N=10 (Sterol ratio ) with at least 1 ERG
ERG results
All 10 moderate patients showed increased implicit times in rods and cones
Amplitudes showed rods affected more than cones
rods showed moderate decrease in amplitude
cones showed mild to moderate changes.
In the 6 patients with serial studies, 4 patients improved and 2 were stable (4 patients more recently enrolled and awaiting follow-up studies)
EUA studies:
3 patients showed mild pigmentary retinopathy which improved on follow-up testing
No progression of RPE seen in any patient
optic nerve hypoplasia seen in 2 patients, and 1 of these also had tortuous vessels

14. Results Severe patients
N=7 (Sterol ratio >17), 6 with at least 1 ERG; (2 patients died of severe disease,1 lost to follow-up, and 1 too medically unstable to undergo procedures under anesthesia)
ERG results
All 6 severe patients showed increased implicit times in both rods and cones
Amplitudes showed rods affected more than cones
rods showed moderate/severe decrease in amplitude
Cone amplitudes were normal!
In the 3 patients with serial studies, 2 patient improved and 1 was stable
EUA studies:
3 patients showed stable pigmentary retinopathy
No progression of RPE seen in any patient, but also no improvement
1 patient showed marked retinal hypopigmentation

15. Summary – ERG findings at baseline
Patients with Smith-Lemli-Opitz syndrome demonstrate abnormalities of retinal function detected on Electroretinogram (ERG)
The abnormalities demonstrated include:
Prolonged implicit times in all patients, regardless of severity of disease
Decreased wave amplitudes in Rod cells were seen in all patients, with a greater change found as disease severity worsened.
Rod cell amplitudes were affected more than cone cells in mild and moderately affected patients
Cone cell amplitudes were NORMAL in severely affected patients – unclear why!!

18. Summary ERG findings on Antioxidant Treatment
Serial studies were done on patients treated with both Cholesterol and AquADEKS
ERG findings showed:
Improvement in amplitude of both rods and cones in all 3 mild patients
Improvement in implicit times in all 3 mild patients
Improvement in rods and cones in 4/6 moderate patients
Improvement in implicit times in 4/6 moderate patients
2/6 moderate patients showed stable results
Improvement in rod amplitude in 2/3 severe patients
Improvement in implicit time in 2/3 severe patients
Cone function remained normal
1 patient showed stable results
NO patient showed worsening of retinal function while on treatment

20. Summary of Ophthalmological Exam under Anesthesia (EUA) findings
Pigmentary Retinopathy worsened over time in patients treated with cholesterol alone (historical finding)
Pigmentary Retinopathy was only seen in a subset of patients
2/7 mild patients
3/10 moderate patients
3/7 severe patients
Pigmentary Retinopathy was present in the periphery and when subtle, required a good exam under anesthesia to document it.
On Antioxidant treatment, Pigmentary Retinopathy improved or remained stable
2/7 mild patients with RP – both improved over time
3/10 moderate patients – both improved over time
3/7 severe patients – 2 improved and 1 stable
No Patient had worsening Pigmentary Retinopathy while receiving both Cholesterol and Antioxidants

21. Retinal SLOS Study Conclusions
Treatment with the antioxidant preparation AquADEKS plus cholesterol appears to lead to an improvement in retinal function in most patients, as seen by an increase in amplitude and a decrease in latency time on ERG testing. The improvement with AquADEKS is more for rods than for cones
Historically, SLOS patients treated with cholesterol alone showed continued worsening of retinal function over time – however it is not known if cholesterol slows this rate, as there is no data available regarding retinal function in SLOS patients prior to the use of cholesterol.

22. Future plans
A collaboration is in place to evaluate oxysterols in plasma of SLOS patients, by Dr Libin Xu in Seattle. Dr Porter’s lab at Vanderbilt is also analyzing the components of AquADEKS to help determine which vitamins are most effective, and doing studies in the parents to develop an easier carrier test.

23. For the Future
This is a small study and it will be important to treat more SLOS patients and follow them for a longer period of time – my goal is to participate in a multi-institutional study to evaluate antioxidant treatment, as well as other possible medications such as bile acids in patients with SLOS
Following oxysterol levels may prove to be helpful and can be done more often and easily than ERG’s
There may be other benefits of antioxidant treatment, particularly regarding hearing, photosensitivity, ability to fight infections, etc which will require future study.

24. SLOS Retinal Studies
This work has been supported by the CTRC at the Denver Children’s Hospital. MO1-RR00069, General Clinical Research Centers Program, NCRR, NIH
I would like to thank my patients, Dr Rebecca Braverman, the Children’s Hospital Colorado Foundation, Ward Rd Pharmacy, and the wonderful CTRC staff at Children’s Hospital Colorado