Prevention of malaria infection in healthy adults by bites of irradiated Plasmodium falciparum-infected mosquitoes: numbers and frequencies of bites and induction of sterile protection.

S Army Medical Research and Materiel Command0 sites50 target enrollmentMay 31, 2016

Overview

Phase: Not Applicable
Intervention: Not specified
Conditions: Not specified
Sponsor: S Army Medical Research and Materiel Command
Enrollment: 50
Status: Completed
Last Updated: 9 years ago

Overview Investigators Eligibility Criteria Outcomes Similar Trials

Overview

Brief Summary

No summary available.

Registry

who.int

Start Date

May 31, 2016

End Date

TBD

Last Updated

9 years ago

Study Type

Interventional

Sex

All

Investigators

Sponsor

S Army Medical Research and Materiel Command

Eligibility Criteria

Inclusion Criteria

•1\. Healthy adults (male or non\-pregnant female) 18\-50 years of age or re\-enrollees up to age 55 years
•2\. Available to participate for expected duration of an initial immunization series and challenge, for immunization and mock\- immunization groups

Exclusion Criteria

•1\. Age \<18 or \>50 (\>60 for re\-enrollees). Reason for exclusion of children: increased risks associated with the blood volumes needed for this study in individuals undergoing growth or of small body size (\<110 POUNDS). Reason for exclusion of older adults: increased risks associated with blood volumes needed for this study in individuals with a greater probability of occult cardiovascular or cerebrovascular disease
•2\. Pregnant females and females that are breast\-feeding. Reason for exclusion: the immunological changes accompanying pregnancy and lactation could alter the results of the assays performed
•3\. Weight less than 110 lbs. for Groups 1 and 3\. Reason: volunteers have to meet NIH donor eligibility criteria of weight \> 110 lbs. in order to be apheresed at the NIH facility
•4\. Known immunodeficiency (e.g. HIV positive), history of autoimmune or connective tissue disease, splenectomy, use of steroids or non\-steroidal anti\-inflammatory drugs, or any immunosuppressive therapy. Reason for exclusion: immune deficiency or immunosuppressive therapy could affect the immunological responses of volunteers and thus the results of the outcome measurements performed in this study
•5\. Evidence of active (acute or chronic) hepatitis B or C infection. Reason for exclusion: a serious, underlying medical condition could affect the immunological responses of volunteers (as above) or could increase the risk or severity of adverse events associated with participation in this study.
•6\. Clinical or laboratory evidence of significant hepatic, renal, cardiac, immunologic or hematologic disease. Reason for exclusion: same as for 5\.
•7\. History of malaria infection, exposure to malaria infection, or receipt of a malaria vaccine. Reason for exclusion: New group 1 volunteers: a principal objective of Stage A is to study the transition from non\-immune to immune status, and this will not be possible if volunteers are partially immune prior to immunization; Group 2 volunteers (infectivity controls): any pre\-existing immunity could prevent these volunteers from acquiring malaria following challenge, falsely indicating that the challenge sporozoites were not viable; Group 3 volunteers (immunology controls): these are the malaria\-negative controls for our laboratory assays, and thus cannot have a history of malaria or exposure to malaria. NB1: This criterion does not apply to the six volunteers from the previous irradiated sporozoite protocol who may elect to enroll in this protocol. NB2: If it is impossible to find enough volunteers meeting this criterion, it may be relaxed for Groups 1 and 3 (e.g., volunteers will not be excluded because of history of exposure to malaria)
•8\. History of anaphylactic reaction to mosquito bites for Groups 1 and 2 volunteers, or Group 3 volunteers if they are to undergo mock\-immunization. Reason for exclusion: to avoid increased risk of anaphylaxis
•9\. Any other significant finding which in the opinion of the investigator would increase the risk of an adverse outcome for volunteers in this protocol, or to compromise the scientific objectives of this protocol