ZK 200775 is an antagonist at the α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor and had earned attention a possible neuroprotective agent in cerebral ischemia. Probands receiving the agent within a stroke therapy related Phase I trial reported on an alteration of visual perception. In this trial, the effects of ZK 200775 on the visual system will be analyzed in detail.

In a randomised, placebo-controlled, double-blind study eyes and vision will be examined before and after the intravenous administration of ZK 200775. The following methods will be applied: clinical examination, visual acuity, ophthalmoscopy, colour vision, rod absolute threshold, central visual field, pattern-reversal visual evoked potentials (pVEP), ON-OFF and full-field electroretinogram (ERG).

Inclusion Criteria:

• The participant must be a voluntary proband
• Age between 55 and 65 years
• Body weight must not exceed the following value: Body height in cm minus 100 = body weight [kg] +/- 20%
• Male sex
• Written informed consent
• Physical examination: Probands must show normal findings without clinical relevance, mental and physical health is required;

Exclusion Criteria:

• Clinical history:

  • Substantial pre-existing medical condition
  • Known allergy to the employed effective components or galenic components

• Medicaments and drugs

  • Intake of systemically or locally acting drugs which conflict with the aim of the trial or that can influence the results (antipsychotic drugs, antidepressants, barbiturates and benzodiazepines)
  • A clinical history that hints to substance or alcohol abuse
  • Nicotine abuse of more than 10 cigarettes a day
  • Consumption of alcoholic beverages on the day prior to the examinations
  • Extreme physical stress (sports or work) within 8 days prior to the examinations
  • Blood donation within 2 months prior to the examinations
  • Relevant vaccination or stay abroad
  • Special or onesided alimentation (strict vegetarianism, low-caloric diet)
  • Simultaneous participation in another clinical trial

• Vital signs (after 3 minutes of rest)

  • Blood pressure with systolic values > 160 mmHg and / or diastolic values > 95 mmHg
  • Heart frequency: Values beyond 50-100 beats per minute

• Electrocardiogram

  • abnormal 12-channel ECG

• Laboratory findings

  • Hepatitis antigen (HBsAG), hepatitis C-antibodies or positive HIV-test

• Clinical pharmacology

  • positive drug test
  • clinically relevant abnormalities of the examined parameters

• Opinion of the investigator: when due to scientific or personal reasons or matters of compliance or safety a patient should not take part in the trial

• Opacification of optic media, retinal disease, optic nerve disease, amblyopia or color vision defects

• Status post intraocular surgery (exception: cataract surgery with implantation of a posterior chamber lens), laser coagulation

• Myopia > -5 diopters, hyperopia > +5 diopters

• Narrow angle glaucoma