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Experimental PfSPZ Vaccine in Adults Without Malaria

This study has been completed.
Sanaria Incorporated
U.S. Military Malaria Vaccine Program
Information provided by:
National Institutes of Health Clinical Center (CC) Identifier:
First received: September 24, 2011
Last updated: April 19, 2017
Last verified: June 5, 2013


  • Malaria parasites are carried by mosquitoes, which spread the infection by biting people. Currently, there is no effective malaria vaccine. However, studies show that volunteers bitten many times by mosquitoes that carry weakened malaria parasites could fight off getting sick with malaria when later exposed to normal malaria parasites. Malaria parasites are weakened by exposing them to radiation when they are in the stage of development called sporozoites . Only the mosquitoes are irradiated and study volunteers are not exposed to radiation. The radiation stops the parasites from being able to cause disease but still promote protection. For many years, it was not possible to give these sporozoites to people as a vaccine since they could not be adequately purified from the mosquito. Scientists have recently figured out how to produce and isolate the weakened sporozoites so that they can be given in an injected vaccine. This vaccine is known as the "PfSPZ vaccine".
  • A malaria challenge will be used to test whether the vaccine will prevent infection. In a malaria challenge, mosquitoes that have the malaria parasite will be allowed to bite a participant's arm. In the event that the vaccine does not work, the malaria parasite used for the challenge can be treated completely with common anti-malaria medications. Participants will be treated immediately if they develop malaria symptoms.


- To test the safety and effectiveness of the PfSPZ vaccine.


- Healthy volunteers between 18 to 45 years of age.


  • Participants will be screened with a physical exam, medical history, and blood tests. There will be five different groups of study participants, all of whom will be monitored with frequent blood tests.
  • Group 1 will have two vaccines with the lowest amount of the vaccine given 4 weeks apart, with regular clinic visits up to 24 weeks after the second vaccine. This group will not have a malaria challenge.
  • Group 2 will have four or six vaccines given 4 weeks apart at a higher dose than group 1. A malaria challenge will be given about 3 weeks after the last vaccine. Follow-up visits will continue through 24 weeks after the last vaccine.
  • Group 3 will have four or six vaccines given 4 weeks apart at a higher dose than group 2. A malaria challenge will be given about 3 weeks after the last vaccination, as for Group 2. Follow-up visits will continue through 24 weeks after last vaccine.
  • Group 4 will have four or six vaccines given 4 weeks apart at a higher dose than group 3. A malaria challenge will be given about 3 weeks after the last vaccination. Follow up visits will continue through 24 weeks after last vaccine.
  • Group 5 will serve as a control group and will not receive the vaccine, but will have the malaria challenge. Follow-up visits will continue through 8 weeks after the challenge.

All participants from any group who receive a malaria challenge will be treated promptly for malaria when it develops.

Condition Intervention Phase
Prevention and Control
Acquired Immunity
Biological: PfSPZ
Phase 1

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Primary Purpose: Prevention
Official Title: VRC 312: A Phase 1, Open-Label, Dose-Escalation Clinical Trial With Experimental Challenge to Evaluate Intravenous Administration of the PfSPZ Vaccine in Malaria-Naive Adults

Resource links provided by NLM:

Further study details as provided by National Institutes of Health Clinical Center (CC):

Primary Outcome Measures:
  • The primary objectives of the study are related to the safety and tolerability of the vaccine at the 4 dosage levels when administered IV.

Secondary Outcome Measures:
  • The secondary objectives are related to PfSPZ vaccine-mediated protection against Plasmodium falciparum (Pf) challenge at the 3 higher dosage levels.

Enrollment: 64
Study Start Date: September 14, 2011
Study Completion Date: June 5, 2013
Primary Completion Date: June 5, 2013 (Final data collection date for primary outcome measure)
  Show Detailed Description


Ages Eligible for Study:   18 Years to 45 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

A volunteer must meet all of the following criteria to be included:

  1. 18 to 45 years old adults.
  2. Able and willing to participate for the duration of the study.
  3. Able to provide proof of identity to the satisfaction of the study clinician completing the enrollment process.
  4. Able and willing to complete the informed consent process.
  5. Willing to donate blood for sample storage to be used for future research.
  6. Willing to refrain from blood donation to blood banks for 3 years following P. falciparum challenge.
  7. Agree not to travel to a malaria endemic region during the entire course of study participation.
  8. Physical examination and laboratory results without clinically significant findings and a body mass index (BMI) less than or equal to 35 for Groups 1, 2, 3 and 4 or BMI less than or equal to 40 for Group 5.


  9. Hemoglobin greater than or equal to 11.2 g/dL for women; greater than or equal to 13.0 g/dL for men.
  10. Differential and platelet count either within institutional normal range or accompanied by site physician approval.
  11. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) less than or equal to 1.25 times upper limit of normal (ULN) for Groups 1, 2, 3 and 4 or less than or equal to 1.75 ULN for Group 5.
  12. Serum creatinine less than or equal to upper limit of normal.
  13. Negative for HIV infection.


  14. Negative sickle cell screening test.


  15. Negative beta-HCG pregnancy test (urine or serum) on day of enrollment for women presumed to be of childbearing potential.
  16. A woman of childbearing potential must agree to use an effective means of birth control throughout the duration of study participation.


A volunteer will be excluded if one or more of the following conditions apply:

  1. Woman who is breast-feeding or planning to become pregnant during the time interval needed to complete the study.
  2. Receipt of a malaria vaccine in a prior clinical trial.
  3. Any history of malaria infection.
  4. Evidence of increased cardiovascular disease risk; defined as >10% five year risk by the non-laboratory method.
  5. Screening EKG showing pathologic Q waves and significant ST-T wave changes; left ventricular hypertrophy; any non-sinus rhythm (except isolated premature atrial contractions); left bundle branch block; or advanced (secondary or tertiary) A-V heart block.
  6. Current use of systemic immunosuppressant pharmacotherapy.
  7. History of a splenectomy, sickle cell disease or sickle cell trait.
  8. Plan for major surgery between enrollment and challenge.
  9. Known allergy to any component of the vaccine formulation; history of anaphylactic response to mosquito-bites; or known allergy to chloroquine phosphate, atovaquone or proguanil.
  10. Participation in any study involving another investigational vaccine or drug within 12 weeks prior to enrollment, or plan to participate in another investigational vaccine/drug research during the study.
  11. Personal beliefs that prohibit the receiving of vaccine product containing human serum albumin within the diluent.
  12. Use or planned use of any drug with anti-malarial activity that would coincide with study vaccination or challenge.
  13. History of psoriasis or porphyria, which may be exacerbated after treatment with chloroquine.
  14. Anticipated use of medications known to cause drug reactions with chloroquine or atovaquone-proguanil (Malarone) such as cimetidine, metoclopramide, antacids, and kaolin.
  15. Psychiatric condition that precludes compliance with the protocol; past or present psychoses; disorder requiring lithium; or within five years prior to enrollment, history of a suicide plan or attempt.
  16. Any medical, psychiatric, social condition, occupational reason or other responsibility that, in the judgment of the investigator, is a contraindication to protocol participation or impairs a volunteer s ability to give informed consent.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01441167

United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Institute of Allergy and Infectious Diseases (NIAID)
Sanaria Incorporated
U.S. Military Malaria Vaccine Program
Principal Investigator: Robert A Seder, M.D. National Institute of Allergy and Infectious Diseases (NIAID)
  More Information

Publications automatically indexed to this study by Identifier (NCT Number): Identifier: NCT01441167     History of Changes
Other Study ID Numbers: 110257
Study First Received: September 24, 2011
Last Updated: April 19, 2017

Keywords provided by National Institutes of Health Clinical Center (CC):
Healthy Subjects
Vaccine-Mediated Protection
Healthy Volunteer

Additional relevant MeSH terms:
Protozoan Infections
Parasitic Diseases
Immunologic Factors
Physiological Effects of Drugs processed this record on April 28, 2017