Sonlicromanol
An investigational treatment for Primary mitochondrial disease (m.3243A>G, MELAS/MIDD spectrum).
The same compound appears under different names depending on the context. Here is how to identify Sonlicromanol wherever you encounter it, plus the key facts at a glance.
- Generic name
- Sonlicromanol
- Development code
- KH176
- Drug class
- Redox modulator (investigational)
- Manufacturer
- Khondrion
- How it's taken
- In the Phase 3 trial, 90 mg of sonlicromanol (100 mg of the hydrochloride salt) or a matching placebo is taken by mouth twice a day.
An oral tablet taken twice a day, in a Phase 3 trial for adults with primary mitochondrial disease caused by the m.3243A>G mitochondrial DNA change (the MELAS and MIDD spectrum). It is not approved anywhere. A separate pediatric Phase 2 trial (KHENERGYC, NCT04846036) that included children with Leigh syndrome is suspended for a strategic company decision, which the sponsor says is not related to safety.
How Sonlicromanol works
Cells with faulty mitochondria make less energy and more damaging by-products called reactive oxygen species. Sonlicromanol is designed to mop up some of that damage and calm the inflammation it causes, so that muscle and nerve cells work better even though the underlying gene fault remains. It does not fix the mitochondrial DNA change itself.
Mechanism: Oral small molecule that its developer describes as reducing harmful oxidative stress inside cells with faulty mitochondria
Side effects and safety
Safety results from the Phase 3 trial have not been published. The trial is double-blind and placebo-controlled, so side effects will be reported against placebo when it reads out after September 2028. Ask the study team what earlier studies showed before enrolling.
This is not a complete list of side effects. Talk to your doctor or pharmacist about what to expect and when to seek medical attention.
Taking Sonlicromanol
In the Phase 3 trial, 90 mg of sonlicromanol (100 mg of the hydrochloride salt) or a matching placebo is taken by mouth twice a day.
Clinical trial results
KHENERFIN (NCT06451757) is a Phase 3, randomized, double-blind, placebo-controlled trial that started in April 2026 and plans to enroll about 220 adults with a confirmed m.3243A>G mitochondrial DNA variant, chronic fatigue for at least 3 months, and mitochondrial myopathy. The main outcomes are a fatigue questionnaire (Neuro-QoL Fatigue) and the 5-times sit-to-stand test. Primary completion is expected in September 2028. Sites are listed in the United States, Denmark, France, Germany, Italy, the Netherlands and the United Kingdom; as of September 2026, 1 of the 3 US sites (UTHealth Houston) was recruiting and the others were not yet recruiting.
Development history
Sonlicromanol was developed by Khondrion, a Dutch company, under the code KH176. Its pivotal Phase 3 trial, KHENERFIN, started in April 2026.
Explore Primary mitochondrial disease (m.3243A>G, MELAS/MIDD spectrum) trials
Common questions about Sonlicromanol
▸What is Sonlicromanol?
An oral tablet taken twice a day, in a Phase 3 trial for adults with primary mitochondrial disease caused by the m.3243A>G mitochondrial DNA change (the MELAS and MIDD spectrum). It is not approved anywhere. A separate pediatric Phase 2 trial (KHENERGYC, NCT04846036) that included children with Leigh syndrome is suspended for a strategic company decision, which the sponsor says is not related to safety.
▸How does Sonlicromanol work?
Cells with faulty mitochondria make less energy and more damaging by-products called reactive oxygen species. Sonlicromanol is designed to mop up some of that damage and calm the inflammation it causes, so that muscle and nerve cells work better even though the underlying gene fault remains. It does not fix the mitochondrial DNA change itself.
▸What are the side effects of Sonlicromanol?
Safety results from the Phase 3 trial have not been published. The trial is double-blind and placebo-controlled, so side effects will be reported against placebo when it reads out after September 2028. Ask the study team what earlier studies showed before enrolling.
▸How is Sonlicromanol taken?
In the Phase 3 trial, 90 mg of sonlicromanol (100 mg of the hydrochloride salt) or a matching placebo is taken by mouth twice a day.
▸Is Sonlicromanol FDA approved?
Sonlicromanol is currently in phase 3 clinical trials for Primary mitochondrial disease (m.3243A>G, MELAS/MIDD spectrum). It has not yet received FDA approval.
▸Is sonlicromanol a treatment for Leigh syndrome?
No. The Phase 3 KHENERFIN trial enrolls adults with the m.3243A>G mitochondrial DNA variant, which causes MELAS and related conditions, not children with Leigh syndrome. A pediatric Phase 2 trial that included Leigh syndrome (KHENERGYC) is suspended for a strategic company decision that the sponsor says is not related to safety. KHENERFIN results are expected after September 2028.
▸Can I join the sonlicromanol trial in the United States?
The KHENERFIN trial (NCT06451757) lists 3 US sites; as of September 2026, UTHealth Houston was recruiting and the others were not yet recruiting. You need to be 18 or older with a confirmed m.3243A>G variant, chronic fatigue and mitochondrial myopathy. Check the ClinicalTrials.gov listing for the current site list and contact details.
Sources and references
Every factual claim on this page is drawn from the public sources listed below. Click any reference to open the original document.
- ClinicalTrials.gov. KHENERFIN Study: A Trial to Evaluate the Efficacy and Safety of Sonlicromanol in Primary Mitochondrial Diseases. https://clinicaltrials.gov/study/NCT06451757