Randomised, double-blind, sequential-group, placebo-controlled, single-ascending oral dose, interventional study, investigating the safety, tolerability, pharmacokinetics, pharmacodynamics and metabolite profile of Lu AF09535 in healthy young men, and an open-label crossover to study intra-subject variability and effects of food

The research medication is a new medication developed for the treatment of
Fragile X Syndrome.

- to examine the safety and tolerability of the research medication
- to examine how the research medication is absorbed, broken down and excreted
by the body.

This is a randomised, double-blind, sequential-group, placebo-controlled,
single-ascending oral dose, interventional study, investigating the safety,
tolerability, pharmacokinetics, pharmacodynamics and metabolite profile of Lu
AF09535 in healthy young men, and an open-label crossover to study
intra-subject variability and effects of food

The study will start with a screening. At the screening a physical examination
will take place and a few other standard
medical assessments will be performed (ECG, vital signs). Furthermore a blood
and urine sample will be taken for
laboratory tests and an alcohol breath test and drug screen will be done.

During the stay in the clinic the subject will receive the study medication and
on several time points blood will be taken
and urine will be collected. The subjects will be asked for possible side
effects on regular basis. Furthermore several
safety assessments will be done frequently. Also EEG assessment will be done in
three cohorts.

Finally, a follow-up visit will take place.

Adverse events as seen in animal studies of Lu AF09535 were balance
difficulties, increased heart rate, decreased blood pressure, and changes to
the measurements of electrical activity in the heart. Events regarding the
heart may be felt as palpitations or dizziness. Moreover, changes in laboratory
liver- and kidney tests, breathing volumes, and body temperature were seen.

Given the fact that Lu AF09535 is not a registered drug and has not been given
to humans before, the doses decided to be administered in this study have been
selected based on animal studies. The risks are thus considered to be minimal,
but unforeseeable side effects could occur. The subjects health will be
monitored carefully and if they experience symptoms, the study physician will
ensure that the subjects receive the appropriate care and treatment, if needed.

The blood collection may cause discomfort or bruising. Occasionally, fainting,
an infection at the blood sampling site, bleeding and blood clot formation can
occur.