Tokuda Hospital Sofia


General Patient Information

Definition of a Clinical Trial

With the aim a new medicine to be on the market it should pass through various clinical trials. These trials prove its quality, safety and efficacy. 

Before conducting a clinical trial, it should be approved and authorized by the health authorities and regulatory organs – they decide if the patients’ rights are protected, if the trial is safe for the patents’ health and what will be the outcome for the patients. 

Before a volunteer or a patient to participate in a clinical trial he/she should receive documents that explain everything about the given clinical trial, so-called informed consent. The informed consent contains everything about the clinical trial – purpose, duration, therapy, procedures, potential benefits, risks etc. Each patient should sign willingly the informed consent before being enrolled in a clinical trial. 

The clinical trials are conducted obligatory by highly qualified and trained medical personnel – investigators and coordinators. All investigators and coordinators follow strict rules, regulations and laws. The guidelines for the clinical trials are called Good Clinical Practice (GCP). GCP is an international ethical and scientific quality standard for designing, conducting, recording and reporting trials. Compliance with this standard provides public assurance that the rights, safety and well-being of trial subjects are protected. 

Clinical Trial Phases

  • Phase I – “First-in-humans” - drug is tested on a small group of people, very often healthy volunteers. It is observed the effect of the drug on the human body, namely what happens when the drug dissolves in the body and how the drug reacts. The primary goal is to determine the appropriate dosing, safety and tolerability.  Whenever the drug is determined to be safe enough, it can be tested in phase II clinical trial to check for efficacy. Usually up to 20 people are enrolled.   
  • Phase II – The studies drug is administered to patients. It is determined the efficacy, optimal dose and safety. It is studied the potential differences in pharmacokinetic behavior between healthy volunteers and patients. Several hundred patients are enrolled. Sometimes different treatments are combined and explored in this phase. If the drug has a good enough effect, it can be tested on a larger group of patients in Phase III.
  • Phase III – Phase III trials enroll more patients - 300-3000 in order to confirm the results from Phase I and Phase II. In this phase it is determined the safety, the efficacy and the effectiveness of the new drug. In this phase are compared therapies with standard-of-care or placebo. The primary aim is to be proved if the studied drug has better effects than its alternatives.
  • Phase IV – Phase IV tests new licensed drugs in large group of patients. The main points for this phase are to follow if there are any more side effects, to prove the safety of the drug, to precise the long term risk and the benefits from the treatment.  


Patient safety during a clinical trial is of a high importance. It is strictly followed by the investigational teams and all kinds of institutions and authorities.


  • Free and innovative treatments
  • Better and more effective treatment than the existing ones
  • Close monitoring and care by one and the same team of doctors
  • First to benefit from new treatments
  • Help other people who will receive the treatment later on when the trial passes all the phases and improvements.


  • The clinical trial may require more time, visits to hospital and even hospitalization
  • There might be side effects
  • Minimal risk thanks to the strict regulations

*All the information about the patents is in the informed consent and all benefits and risks should be discussed with your doctor.

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Hospital location

51B Nikola Y. Vaptsarov Blvd., Sofia, 1407 (if you drive, the entrance is from Atanas Dukov str.)

The hospital has a parking lot for patients and visitors. The first 30 min. are free of charge, every next hour is 3BGN/hrs.
IMPORTANT! Have in mind that the parking lot is very busy Monday to Friday between 10.00 and 14.00. The hospital team will appreciate if those whose health condition allow, take the drop off option without parking or use other transport means or alternative parking lots in the area.

Public transport:
Buses: №88, 120

Metro lines: You can get off at James Bourchier or Vitosha metro station and walk to the hospital.


From the Central Railway Station

Bus: take bus #305 and get off at Romanian Embassy stop, then transfer to bus #120 to Tokuda Hospital stop.

Metro: Take metro line Nadezda-Lozenetz and get off either at James Bourchier or Vitosha metro station, then walk to the hospital.