Healthy volunteers

Healthy Volunteers

Healthy Volunteers for Clinical Studies

Convex Clinical Research Institution constantly maintains and develops a database of healthy volunteers ready to participate in clinical trials and medical device investigations. On a weekly basis we communicate with our study participants to ensure their future interest in participating within our clinical projects. With a database of over 1800 potential healthy volunteers we meet our sponsors’ expectations of recruitment strategy and study goals. We reach healthy volunteers recruitment within timelines given by our sponsor companies. We focus on excellent communication with our participants, which we believe, it is the key factor for successful study subject recruitment and retention. Our clinical research team helps build relationships with participants and ensure their needs and requirements are met. On a project basis we gather healthy volunteers’ feedback about their experiences and improve our services so that we improve their hospital stay with us. During the entire course of the study, volunteers’ satisfaction is our primary focus. Our healthy subject database includes over 1800 non-smoking subjects. It consists of students and young people representing 84 % of our participants and a second group of 55+ aged (postmenopausal and elderly) participants. Please contact us with a request and we can share more information on our healthy subject population.

Healthy Volunteers Studies

For healthy volunteers

As a healthy volunteer, you have the opportunity to participate in one of our clinical research programs that are conducted at Convex Pharmacology unit.
In order for this to happen you must meet certain inclusion criteria. Before any start you need to be aware of that you have no acute or chronic medical conditions and you have not participated in any other clinical studies in the last 6 months
If you meet these 2 basic criteria please contact our specialist and discuss more on your potential participation in the clinical studies that are currently under processing.

In order to proceed, you will need to go through several stages of assessment:

Stage 1: Introducing the participant to the clinical study. During this stage, the participant receives basic information about nature and progress of a clinical study including information on: drug under investigation, potential risks of participation, study duration, procedures and etc.
Stage 2: Informed consent.  You are provided with an informed consent in a language that is understandable to you, which contains full information about your participation during the course of the study.
Stage 3: A detailed discussion with the principal investigator about your participation. During this discussion with a clinical investigator, you will be encouraged to ask any questions that you may have and receive clarification regarding your participation. In case you have missed an important question, it can be discussed with the clinical study investigator at a later stage before ICF is being signed. It is advisable to discuss your participation with your family doctor or your family members. If you wish to proceed you will be invited to the next stage of the process:
Stage 4: Signing an informed consent. In the presence of the medical team members, you and a principal investigator will sign and date the informed consent. Please note that you have the right to withdraw your consent and to terminate further consent at any time without giving a specific reason.
Stage 5: A complete examination to assess your health. After finalizing your informed consent and if you are willing to further participate, you will proceed to a full medical examination. A blood sample will be taken from you for testing. If you have been assessed by the research team as a healthy volunteer and meet all criteria for inclusion in a clinical study, you can move forward.

For more information about healthy volunteers clinical studies, please contact us via phone.

Convex Healthy Volunteers Clinical Studies

Being a participant, it is completely normal to be concerned about your safety. That is why here at Convex Clinical Research Center, the welfare of our participants is our top priority. The initial documentation for every clinical trial we undertake is submitted to the Bulgarian Drug Agency and to the Central Ethics Committee. As independent regulatory bodies they review the available information and ensure that each trial maintains the highest levels of safety before giving their approval. Prior to any on-site assessments or screening procedures, you will be asked to sign an Informed Consent Form to confirm that you completely understand what is expected of you as a clinical trial volunteer. One of our physicians/ investigators will be assisting you in the process of signing and will give you the opportunity to ask any questions you may have about the clinical study, your safety and the possible side effects.

How do we recruit potential trial subjects:

  • from a paper or electronic database of people who have indicated their willingness to take part in a trial; 
  • by advertisements in a newspaper or magazine, on a noticeboard in places such as a university or hospital, on the radio or television, on a website or through social media; 
  • by word of mouth, or
  • by referral from another doctor.

All study-specific advertisements must be approved by a EC. The Clinical Trials Directive guidance document on EC applications give advice about advertising for subjects for clinical trials. Advertisements should say that the trial involves research and that the advertisement has been approved by a EC, and should give a contact name and phone number and some of the selection criteria. In addition, advertisements may give the purpose of the clinical trial, where it will take place and the name of the company or institution carrying it out.

However, advertisements must never over-stress payment, use EC or BDA approval as an inducement, name and promote the product, or claim that it is safe. To ensure consistency, in the advertising for Phase I studies should seek ethical advice on the procedures. Whatever the method of recruitment, subjects must be recruited of their own free will. They should not be made to feel obliged to take part in a clinical trial, nor should they suffer in any way if they do not take part.

Additionally, they should be recruited only if they:

  • are capable of giving valid consent, and
  • have been fully and properly informed so that they understand: the nature and purpose of the trial, any risks, either known or suspected, and any inconvenience, discomfort or pain that they are likely to experience 
  • that they can withdraw at any time and without giving a reason
  • that the investigator may withdraw them at any time if they do not follow the protocol or if their health is at risk.

At Convex we keep records of subjects who take part in their trials and avoid excessive use of any subject. The number of trials that a subject may take part in during any 12-month period will depend on: 

  • the types of IMP and their half-lives
  • the routes of administration of the IMP
  • the frequency and duration of exposure to the IMP
  • the procedures involved, and
  • the total volume of blood taken from the subject.

Subjects must not:

  • take part in more than one trial at a time

Trial subjects must provide proof of identity before they take part in a trial and should be monitored and prevented from taking part in too many trials. The ways to ensure this are:

  • counselling the subject
  • including warnings in the information leaflet and consent form
  • keep a register of their clinical trials and subjects who have taken part in them 
  • contacting the GP
  • being vigilant when screening trial subjects, e.g., looking for evidence, such as needle marks on the forearm and low blood counts, that the subject may have taken part in a trial recently, and

The inclusion of women as early as possible in drug development might be a valuable clinical strategy depending on the characteristics of the IMP and on its primary indication.

In the exploratory Phase I trials such as single and multiple ascending doses, women will typically be of non-child-bearing potential being subject to the standard inclusion/exclusion criteria for the trial to be conducted.

However, when a sponsor has decided to include Women Of Child Bearing Potential (WOCBP), particular considerations should be given depending on the speculated magnitude of human teratogenicity/fetotoxicity.

Informed consent can be sought by the investigator or a delegate (doctors, healthcare professionals, non-healthcare professionals with appropriate training). They must:

  • obtain the consent of subjects only after the EC has approved in writing the information and consent form
  • fully inform potential trial subjects before they agree to take part in the trial
  • give the subjects oral and written information that is free of jargon and is easy to understand
  • give the subjects enough time and opportunity to ask questions about the trial, answer their questions accurately and honestly, and ensure that they understand the answers
  • ensure that neither the investigator nor other staff coerce subjects to take part or continue to take part in the trial
  • give the subjects, in writing and after approval of the EC, any new information that might make them change their mind about taking part in the trial, and
  • ensure that the subjects, and who informs them, sign and date a consent form, and are given a copy.

The written informed consent form and any other written information to be provided to subjects for an FIH trial present unique challenges to the author. The document must provide an interpretation of risk derived solely from pre-clinical data and knowledge of the pharmacological target in a way that is easily understood by a lay person. In the choice of site, the sponsor should check that the site has robust consent procedures in place, and should consider the PI’s experience in writing or reviewing informed consent documents.

Some specifics of the informed consent documentation for FIH clinical trials are different from those of later trials or later phase trials. For example, in most cases with FIH clinical trials, the written informed consent form is drafted by the unit staff rather than the sponsor, and it must contain the rationale in lay language for the start dose and the maximum dose.

The critically important information on the drug characteristics (pharmacological and toxicological) to support the start dose and the maximum dose should be provided by the sponsor who also bears a responsibility for the wording being chosen to be easily understood by a lay person. Otherwise, the elements of the informed consent discussion and the written informed consent form must comply with the Good Clinical Practice

The investigator should judge trial subjects suitable on the basis of exams, such as:

  • a medical history and examination
  • medicines taken within a set period before the start of the trial
  • a 12-lead ECG
  • safety tests of blood and urine
  • tests for drugs of abuse – such as alcohol, cannabinoids, cocaine, morphine, benzodiazepines, barbiturates and amphetamines
  • tests for HIV, hepatitis B and hepatitis C
  • pregnancy tests in women capable of having a child and at risk of becoming pregnant
  • trial-specific tests, such as 24-hour ambulatory ECG, echocardiogram, lung function tests, kidney function tests and genetic tests
  • for IMPs that affect the immune system: tests to exclude active or recent infections, such as tuberculosis and Genito-urinary infection, and willingness not to travel to countries for which vaccinations are intended or that present a higher risk of infectious diseases during the period that the IMP may be active, and
  • information from the General Practitioner.

Before subjects decide to have the tests for viruses and for drugs of abuse, the investigator must explain to them what will happen if one of the tests turns out to be positive. 

Healthy subjects often have minor out-of-range results of safety tests of blood and urine, and minor variants of the ECG. Some CRAs/ medical monitors and auditors regard these as deviations from the protocol of a trial in healthy subjects. However, usually they have no clinical relevance and do not justify excluding subjects from a trial. A physician should decide their clinical relevance, and the protocol should allow for use of clinical judgment. 

The investigator should ask potential trial subjects for permission to contact their General Practitioner (GP). Subjects who do not have a GP or do not want their GP to be contacted should be excluded from the trial unless there is a good reason to the contrary.

The investigator should inform the GP that their patients have agreed to take part in a trial and should ask if their patients:

  • have or have had any relevant illnesses
  • are taking or have recently taken any medicines
  • have taken part in another clinical trial recently.

The investigator should ask the GP to reply in writing. The investigator must be able to justify including in the trial a subject whose GP does not give any information. Whether or not the GP responds, the investigator is ultimately responsible for making sure that subjects are suitable for the trial before allowing them to take part in it.

The investigator must assess the health of trial subjects throughout the trial and should withdraw any subject whose health is at risk. The methods should include:

  • asking subjects about adverse events; 
  • medical examinations; 
  • measuring vital signs such as heart rate and blood pressure; 
  • safety tests of blood and urine; 
  • continuous monitoring of variables such as the ECG and pulse oximetry, and 
  • trial-specific tests, such as lung function tests.

The clinical trial protocol should include information on follow-up requirements. For example, the investigator will follow up:

  • all subjects after their last dose of IMP, for a period which is indicated in the protocol, depending on the IMP and the trial; 
  • subjects with adverse events, including clinically-relevant abnormal laboratory results, until they have resolved or it is clear that they are resolving, and; 
  • subjects who withdraw or are withdrawn from a trial, as if they had completed it, providing they agree.
Data base of healthy subjectsEvery year hundreds of healthy volunteers participate in our research programmes. Based on the length of the clinical study or subjects involvement the studies are paid differently.
Healthy subjectAny non-smoking person, over 18 years of age, who has no chronic or accute disease can freely register for further clinical assessments and participation into our clinical trial pipeline.
Clinical trial durationA Clinical trial can vary between single ambulatory visit tomultiple site visits or from 24 hour site stay to 30 days of hospitalization. A study might have a long period of follow-up after the clinical trial treatment phase is completed.
Paid clinical studiesAll clinical trials which enroll healthy subjects are paid. Reimbursement fee depends on many details over a study design, time participation and variety of clinical reserch procedures involved.
Clinical research center with phase I unitOur research institution is build-up in a way to confort our research participants so that everyone can enjoy their time during the entire course of a clinical research study.