A Phase 1/2 interventional study of ADX-629 in Sjogren-Larsson Syndrome, sponsored by University of Nebraska. Completed at 1 site in United States. Open to participants aged 5 Years to 50 Years. Per ClinicalTrials.gov, last updated 2026-05-05.
Sponsored by University of Nebraska · Phase 1/2, Interventional, and Treatment
This research study will determine whether orally administered ADX-629 is safe and has biochemical efficacy in participants with Sjögren-Larsson syndrome (SLS), a rare inherited disorder of fatty aldehyde metabolism The disease is caused by bi-allelic mutations in ALDH3A2, which results in deficient activity of fatty aldehyde dehydrogenase (FALDH) and leads to the build-up of harmful long-chain (C16-C20) aldehydes and alcohols. Accumulation of these lipids and their metabolic products in skin, brain and eyes is responsible for the symptoms, which persist lifelong. ADX-629 is an aldehyde trapping agent that is expected to eliminate fatty aldehydes and negate aldehyde toxicity, improve the biochemical abnormalities and have clinical efficacy for SLS.
The primary objective of this clinical protocol is to determine whether ADX-629 is safe and tolerable for use in SLS subjects. The secondary objective is to determine the efficacy of ADX-629 in reversing the biochemical abnormalities in SLS. Exploratory objectives are to evaluate the short-term clinical effects of ADX-629 on neurologic, cutaneous and ophthalmologic disease in SLS. Participants will be treated with ADX-629 for 12 weeks and monitored for safety and biochemical efficacy.
Sjögren-Larsson syndrome (SLS) is a rare inherited disorder of fatty aldehyde metabolism characterized by congenital ichthyosis, spastic diplegia, intellectual disability, seizures and a distinctive retinopathy. The disease is caused by bi-allelic mutations in ALDH3A2, which results in deficient activity of fatty aldehyde dehydrogenase (FALDH) and leads to the build-up of harmful long-chain (C16-C20) aldehydes and alcohols. Accumulation of these lipids and their metabolic products in skin, brain and eyes is responsible for the symptoms, which persist lifelong. Investigators hypothesize that elimination of fatty aldehydes using the oral pharmacologic aldehyde trapping agent ADX-629 will negate aldehyde toxicity, improve the biochemical abnormalities and have clinical efficacy for SLS patients.
This study is an open label, Phase 1/2, single center investigation of ADX-629 in SLS. The primary objective is to determine whether ADX-629 is safe and tolerable for use in SLS participants. The secondary objective is to determine the efficacy of ADX-629 in reversing the biochemical abnormalities in SLS. Exploratory objectives are to evaluate the short-term clinical effects of ADX-629 on neurologic, cutaneous and ophthalmologic disease in SLS.
Up to 10 paticipants with genetically confirmed SLS who meet eligibility criteria will be enrolled. All participantss will be studied at the University of Nebraska Medical Center/Children's Hospital \& Medical Center in Omaha, Nebraska. Participants will be treated with ADX-629 administered orally as 250 mg tablets for 12 weeks. Participants will be monitored for safety of ADX-629 every 4 weeks by physical examination and biochemical safety tests.
The effects of ADX-629 on SLS-specific biomarkers will be determined after 12 weeks of drug treatment. Clinical tests will monitor neurological, dermatological and ophthalmologic response to drug.
33 studies on the registry are indexed under Ichthyosis; 11 are open to participants now.
This study's enrollment of 8 is below the median of 26 across 23 interventional studies indexed under Ichthyosis.
Browse Ichthyosis studies →University of Nebraska is the lead sponsor of 496 studies on the registry; 67 are open to participants now.
Of its 83 completed or terminated interventional studies of FDA-regulated products, 53 (64%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Child-Pugh class
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Open label treatment with ADX-629
Drug: ADX-629
Particpants 10-50 years old will be administered ADX-629 250 mg tablets twice daily. Participants 5-9 years old will be administered ADX-629 125 mg tablets twice daily.
Also known as: Open label
Number of Participants With Treatment-related Adverse Events as Assessed by CTCAE v4.0
Participants are required to report any adverse events as they arise and will be contacted weekly for information regarding adverse events. Physical examinations with vital signs will be done monthly.
Time frame: weekly for 12 weeks
Number of Participants With Abnormal Drug-related Safety Blood Tests
Participants will have monthly medical tests to monitor safety of ADX-629 including complete blood count, comprehensive chemistry panel, vitamin A, vitamin B6 (pyridoxal phosphate), homocysteine, and urinalysis.
Time frame: monthly for 12 weeks
Compliance and Tolerability of ADX-629
A written drug log will be required for recording daily administration of ADX-629 tablets and any problems tolerating the drug. Unused tablets will be counted as a measure of compliance.
Time frame: daily for 12 weeks
Biochemical Efficacy of ADX-629 as Determined by Reversal of Abnormal Biomarkers
Biochemical efficacy of ADX-629 in reversing disease-specific abnormalities in blood levels of fatty alcohols, alkylglycerol lipids, SLS metabolomic profile, SLS lipid profile, and oxidative stress markers. Skin elasticity and thickness, transepidermal water loss, stratum corneum fatty alcohols and alkylglycerol lipids will also be measured.
Time frame: Tests will be done at week 1 and week 12.
Exploratory Clinical Outcomes to Determine Drug Dependent Changes in Abnormal Clinical Measures
Clinical response to ADX-629 will be determined with brain MRI, magnetic resonance spectroscopy, EEG, clinical spasticity scores, visual index of ichthyosis severity score, and SLS retinopathy based on eye exam and retinal photographs.
Time frame: Examinations and procedures will be done at week 1 and week 12.
Plan to share: No — Aggregate de-identified data will be shared with other investigators by request.
This study is completed, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: ADX-629