Idebenone

Key takeaways

Idebenone belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Idebenone to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Idebenone from memory before moving on to harder problems.

Reference excerpt

Idebenone, sold under the brand name Raxone among others, is a medication that was initially developed by Takeda Pharmaceutical Company for the treatment of Alzheimer's disease and other cognitive defects. This has been met with limited success. The Swiss company Santhera Pharmaceuticals has started to investigate it for the treatment of neuromuscular diseases. In 2010, early clinical trials for the treatment of Friedreich's ataxia and Duchenne muscular dystrophy have been completed. As of December 2013 the drug is not approved for these indications in North America or Europe. It is approved by the European Medicines Agency (EMA) for use in Leber's hereditary optic neuropathy (LHON) and was designated an orphan drug in 2007. Chemically, idebenone is an organic compound of the quinone family. It is also promoted commercially as a synthetic analog of coenzyme Q10 (CoQ10).

Uses

Indications that are or were approved in some territories

Nootropic effects and Alzheimer's disease Idebenone improved learning and memory in experiments with mice. In humans, evaluation of Surrogate endpoints like electroretinography, auditory evoked potentials and visual analogue scales also suggested positive nootropic effects, but larger studies with hard endpoints are missing. Research on idebenone as a potential therapy of Alzheimer's disease have been inconsistent, but there may be a trend for a slight benefit. In May 1998, the approval for this indication was cancelled in Japan due to the lack of proven effects. In some European countries, the drug is available for the treatment of individual patients in special cases.

Friedreich's ataxia (Sovrima) Preliminary testing has been done in humans and found idebenone to be a safe treatment for Friedreich's ataxia (FA), exhibiting a positive effect on cardiac hypertrophy and neurological function. The latter was only significantly improved in young patients. In a different experiment, a one-year test on eight patients, idebenone reduced the rate of deterioration of cardiac function, but without halting the progression of ataxia. The drug was approved for Friedreich's ataxia in Canada in 2008 under conditions including proof of efficacy in further clinical trials. However, in February 2013, Health Canada announced that idebenone would be voluntarily recalled as of April 2013 by its Canadian manufacturer, Santhera Pharmaceuticals, due to the failure of the drug to show efficacy in the further clinical trials that were conducted. In 2008, the European Medicines Agency (EMA) refused a marketing authorisation for this indication. As of 2013 the drug was not approved for FA in Europe nor in the US, where, as of February 2023, there is only one approved treatment.

Leber's hereditary optic neuropathy (Raxone) Leber's hereditary optic neuropathy (LHON) is a mitochondrially inherited (mother to all offspring) degeneration of retinal ganglion cells (RGCs) and their axons that leads to an acute or subacute loss of central vision; this affects predominantly young adult males. Santhera completed a Phase III clinical trial in this indication in Europe with positive results, and submitted an application to market the drug to European regulators in July 2011. It is approved by EMA for this indication and was designated an orphan drug in 2007.

Indications being explored

Duchenne muscular dystrophy (Catena) After experiments in mice and preliminary studies in humans, idebenone has entered Phase II clinical trials in 2005 and Phase III trials in 2009.

Other neuromuscular diseases Phase I and II clinical trial for the treatment of MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) was conducted. Phase I/II trial for primary progressive multiple sclerosis concluded that Idebenone did not inhibit disability progression. As of 2022, a phase III clinical trial is ongoing for the treatment of Parkinson's disease.

Life style Idebenone is claimed to have properties similar to CoQ10 in its antioxidant properties, and has therefore been used in anti-aging on the basis of free-radical theory. Clinical evidence for this use is missing. It has been used in topical applications to treat wrinkles.

Pharmacology In cellular and tissue models, idebenone acts as a transporter in the electron transport chain of mitochondria and thus increases the production of adenosine triphosphate (ATP) which is the main energy source for cells, and also inhibits lipoperoxide formation. Positive effects on the energy household of mitochondria has also been observed in animal models. Clinical relevance of these findings has not been established.

Pharmacokinetics Idebenone is well absorbed from the gut but undergoes excessive first pass metabolism in the liver, so that less than 1% reach the circulation. This rate can be improved with special formulations (suspensions) of idebenone and by administering it together with fat food; but even taking these measures bioavailability still seems to be considerably less than 14% in humans. More than 99% of the circulating drug are bound to plasma proteins. Idebenone metabolites include glucuronides and sulfates, which are mainly (~80%) excreted via the urine.

References

Illustrations

Worked examples

Example 1 — a first encounter with Idebenone

Start with the simplest possible case. Write down what Idebenone claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Idebenone before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Idebenone ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Idebenone

In research: Idebenone appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Idebenone in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Idebenone is common in secondary-school and first-year university syllabi. It links to neighbouring topics 1,4-Benzoquinones, Antioxidants, Orphan drugs, so understanding it makes those chapters shorter.
In everyday life: Look for Idebenone outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Idebenone in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Idebenone means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Idebenone out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Idebenone in simple terms?

Idebenone, sold under the brand name Raxone among others, is a medication that was initially developed by Takeda Pharmaceutical Company for the treatment of Alzheimer's disease and other cognitive defects. This has been met with limited success.

Why does Idebenone matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Idebenone?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Idebenone.