Coadministration of GA2 Sporozoites With Adjuvants

• Status: Not yet recruiting
• Trial end date: 2023-11-01
• Target enrollment: 0
• Participant gender: All

Summary

This study will assess the coadministration of genetically attenuated Plasmodium falciparum ∆mei2 (GA2) sporozoites with adjuvants (BCG and YF-17D vaccination and imiquimod cream). Primary outcomes will be safety, tolerability and protective efficacy against CHMI.

• Phase: Early Phase 1
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Leiden University Medical Center
• Treatments: Imiquimod

Criteria

Inclusion Criteria:

1. Participant is aged ≥18 and ≤35 years and in good health.

2. Participant has adequate understanding of the procedures of the study and agrees to abide strictly thereby.

3. Participant is able to communicate well with the investigator

4. Participant is available to attend all essential study visits.

5. Participant agrees that his/her general practitioner (GP) will be informed about participation in the study.

6. Participant agrees to refrain from blood donation to the national blood bank or for other purposes throughout the study period and for a defined period thereafter according to national blood bank guidelines.

7. Participants of child bearing potential (i.e., have an uterus and are neither surgically sterilized nor post-menopausal) agree to use adequate contraception and to not breastfeed for the duration of study.

8. Participant agrees to refrain from intensive physical exercise (disproportionate to the participants' usual daily activity or exercise routine) for twenty-one days following the immunization and during the malaria challenge period.

9. Participant signs informed consent.

Exclusion Criteria:

• 1. Any history, or evidence at screening, of clinically significant symptoms, physical signs or abnormal laboratory values suggestive of systemic conditions which could compromise the health of the participant during the study or interfere with the interpretation of the study results. These include, but are not limited to, any of the following:

a. Body Mass Index (BMI) >35.0 kg/m2 at screening. b. An elevated risk of cardiovascular disease, defined as: i. An estimated ten-year risk of fatal cardiovascular disease of ≥5% at screening, as determined by the Systematic Coronary Risk Evaluation 2 (SCORE2) .

ii. History, or evidence at screening, of clinically significant arrhythmia's, prolonged QT-interval or other clinically relevant ECG abnormalities; or iii. A positive family history of cardiac events in first- or second-degree relatives (according to the system used in medical genetics) <50 years old.

c. Known functional asplenia, sickle cell trait/disease, thalassemia trait/disease or G6PD deficiency.

d. History of epilepsy in the period of five years prior to study onset, even if no longer on medication.

e. Positive HIV, HBV or HCV screening tests. f. Chronic use of i) immunosuppressive drugs, ii) antibiotics, iii) or other drugs that might have an influence on the immune system (excluding inhaled and topical corticosteroids and incidental use of oral anti-histamines), within three months prior to study onset or expected use of such during the study period.

g. Skin disease affecting the site of administration in such a way that administration of mosquito bites or adjuvants is deemed impossible by investigator.

h. History of malignancy of any organ system (other than localized basal cell carcinoma of the skin), treated or untreated, within the past five years.

i. Any history of treatment for severe psychiatric disease by a psychiatrist in the past year.

j. History of drug or alcohol abuse interfering with normal social functioning in the period of one year prior to study onset, positive urine toxicology test for cocaine or amphetamines at screening.

2. For participants of child bearing potential: breastfeeding, or positive urine pregnancy test prior to immunization or prior to CHMI.

3. Any history of malaria or previous participation in any malaria (vaccine) study or CHMI.

4. Known hypersensitivity to or contra-indications for both atovaquone/proguanil or artemether/lumefantrine. QT prolonging drugs are only considered an exclusion criterion when QT prolongation is observed at the ECG at screening.

5. A history of severe (allergic) reactions to mosquito bites. 6. Any history of infection with mycobacteria or BCG vaccination. 7. Any history of infection with yellow fever virus or yellow fever vaccination.

8. Participation in any other clinical study assessing an investigational medical product in the 30 days prior to the start of the study or during the study period.

9. Any condition or situation that could influence the independent consent of participant (e.g. being a direct colleague or family member of study personnel.

10. Any other condition or situation that would, in the opinion of the investigator, place the participant at an unacceptable risk of injury or render the participant unable to meet the requirements of the protocol or would compromise the integrity of the data.