Sequential Optimization of Dose and Schedule of PfSPZ Vaccine

Malaria Clinical Trial

Official title:

Sequential Optimization of Dose and Schedule of PfSPZ Vaccine, Verified by Randomized, Controlled, Double-blind Immunization and Controlled Human Malaria Infection in Malaria-naïve, Healthy Adult Volunteers in Germany

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02704533
• Other study ID #: MAVACHE
• Secondary ID: 2015-005123-11
• Status: Completed
• Phase: Phase 1
• Start date: August 29, 2016
• Est. completion date: December 2018

Study information

• Verified date: January 2019
• Source: Sanaria Inc.
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

MAVACHE is a sequential dose and schedule optimization trial of intravenous immunization with PfSPZ Vaccine in 18 to 54 malaria-naïve, healthy adult volunteers receiving 9x10^5, 1.35x10^6, or 2.7x10^6 PfSPZ per dose and a total dose between 2.7x10^6 and 8.1x10^6 PfSPZ followed by CHMI with 3,200 fully infectious PfSPZ (PfSPZ Challenge).

PfSPZ Challenge (7G8) to assess vaccine efficacy, safety, tolerability and infectivity of ascending PfSPZ doses will be assessed in healthy, malaria-naïve volunteers.

Description:

The study is to take place at Institut für Tropenmedizin, Eberhard Karls Universität Tübingen, Tübingen Germany.

The study has two phases: 1) dose optimization, and 2) regimen verification. In the first phase groups A, B1, B2, C1, C2 and C3 will be vaccinated sequentially in a pre-specified order, followed by homologous CHMI with 3,200 PfSPZ Challenge (NF54) three weeks after last vaccine injection.

Dose optimization phase A: 9x10^5 PfSPZ on Days 0, 7 and 28 (n = 6) B1: 1.35x10^6 PfSPZ on Days 0 and 7 (n = 6) B2: 1.35x10^6 PfSPZ on Days 0, 7, and 28 (n = 6) C1: 2.7x10^6 PfSPZ on Day 0 (n = 6) C2: 2.7x10^6 PfSPZ on Day 0 and 7 (n = 6) C3: 2.7x10^6 PfSPZ on Days 0, 7 and 28 (n = 6)

In parallel to CHMI with PfSPZ Challenge (NF54) during the optimization phase, a total of nine volunteers will receive either 800, 1,600 or 3,200 PfSPZ Challenge (7G8) (PfSPZ Challenge (7G8) dose finding) to assess safety, tolerability and infectivity of PfSPZ Challenge (7G8) in malaria-naïve healthy adult volunteers.

PfSPZ Challenge (7G8) dose finding/infection D1: 800 PfSPZ (n = 3) D2: 1,600 PfSPZ (n = 3) D3: 3,200 PfSPZ (n = 3)

Subsequently, the shortest efficacious regimen (V1) and a three-dose regimen (Day 0, 7 and 28) of the highest safe dose (V2) will be selected and verified against placebo (normal saline (NS)). Groups V1 and V2 will be vaccinated at approximately the same time and undergo repeat CHMI three and eight weeks after the last immunization. Volunteers will either receive PfSPZ Vaccine or NS as placebo. Allocation will be random and double blind. Repeat CHMI will be done with PfSPZ Challenge (NF54) and PfSPZ Challenge (7G8), given in a randomized sequence. All immunizations are given by direct venous inoculation (DVI).

Regimen verification phase V1: Shortest efficacious regimen (n = 12) against placebo (n = 6) V2: Maximum regimen (n = 12) against placebo (n = 6) P1: Placebo for V1 group (n=6) P2 Placebo for V2 group (n=6)

Recruitment information / eligibility

• Status: Completed
• Enrollment: 45
• Est. completion date: December 2018
• Est. primary completion date: October 19, 2018
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 45 Years

Eligibility

Inclusion Criteria:

• Healthy adults aged 18 to 45 years

• Able and willing (in the Investigator's opinion) to comply with all study requirements

• Willing to allow the investigators to discuss the volunteer's medical history with their general practitioner ('Hausarzt' in German) if required

• Residence in Tübingen or surroundings for the period of the trial

• Women only: Must agree to practice continuous effective contraception for the duration of the study (a method which results in a failure rate less than 1% per year)

• Agreement to refrain from blood donation during the course of the study and after the end of their involvement in the study according to the local and national blood banking eligibility criteria (currently there is a four year restriction in Germany)

• Written informed consent to receive PfSPZ products:

• Optimization phase: PfSPZ Vaccine for immunization and PfSPZ Challenge (NF54) for CHMI

• PfSPZ Challenge (7G8) dose finding: PfSPZ Challenge (7G8) for CHMI

• Verification phase: PfSPZ Vaccine for immunization, PfSPZ Challenge (NF54) and PfSPZ Challenge (7G8) for CHMI

• Reachable (24/7) by mobile phone during the immunization and CHMI period

• Willingness to take a curative antimalarial regimen following CHMI

• Agreement to stay overnight for observation during the period of intensive follow-up post-challenge if required

• Answer all questions on the informed consent quiz correctly

• A body mass index <35

Exclusion Criteria:

• History of P. falciparum malaria

• Planned travel to malaria endemic areas before end of CHMI (28 days after CHMI)

• Use of systemic antibiotics with known antimalarial activity within 30 days of study enrollment (e.g. trimethoprim-sulfamethoxazole, doxycycline, tetracycline, clindamycin, erythromycin, fluoroquinolones, or azithromycin)

• Receipt of an investigational product in the 30 days preceding enrollment, or planned receipt during the study period

• Prior receipt of a malaria vaccine

• Immunization with more than three other vaccines within the past four weeks

• HIV infection

• Any confirmed or suspected immunosuppressive or immunodeficient state, asplenia, recurrent, severe infections and chronic (more than 14 days) immunosuppressant medication within the past 6 months (inhaled and topical steroids are allowed)

• Use of immunoglobulins or blood products within 3 months prior to enrolment

• Known or suspected hemolytic disease or presence of hemoglobinopathies

• Pregnancy, lactation or intention to become pregnant during the study

• Contraindications to the use of the following antimalarial medications:

atovaquoneproguanil, artemether-lumefantrine or mefloquine

• History of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ)

• History of serious psychiatric condition that may affect participation in the study (including but not restricted to organic, including symptomatic, mental disorders [ICD-10 code: F00-F09], schizophrenia, schizotypal and delusional disorders [F20-F29], mood (affective) disorders [F30-F39], mental retardation [F70-F79], Disorders of psychological development [F80-F89] or any other psychiatric condition that required hospitalization or psychiatric treatment over an extended period).

• Any other serious chronic illness requiring hospital specialist supervision

• Suspected or known current alcohol abuse as defined by an alcohol intake of greater than 60 g (men) or 40 g (women) per day or a carbohydrate deficient transferrin (CDT) level =2.5%

• Suspected or known injecting drug abuse in the 5 years preceding enrollment

• Positive for hepatitis B surface antigen (HBs-antigen)

• Seropositive for hepatitis C virus (antibodies to HCV)

• Falling in moderate risk or higher categories for fatal or non-fatal cardiovascular event within 5 years (>10%) determined by non-invasive criteria for cardiac risk

• Abnormal electrocardiogram on screening: pathologic Q wave and significant ST-T wave changes, left ventricular hypertrophy, clinically significant arrhythmias, left bundle branch block, secondary or tertiary A-V heart block

• A QT/QTcB interval >450 ms

• Volunteers unable to be closely followed for social, geographic or psychological reasons

• Any clinically significant abnormal finding on biochemistry or hematology blood tests, urine analysis or clinical examination

• History of seizure (except isolated and uncomplicated febrile convulsion at childhood)

• Any other significant disease, disorder or finding which, in the opinion of the investigator, may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study or impair interpretation of the study data

Related Conditions & MeSH terms

• Malaria

Intervention

Biological:
• PfSPZ Vaccine
Aseptic, purified, vialed, cryopreserved, radiation-attenuated, Plasmodium falciparum sporozoites, strain NF54
• PfSPZ Challenge (NF54)
Live, infectious, aseptic, purified, vialed, cryopreserved, Plasmodium falciparum sporozoites, strain NF54
• PfSPZ Challenge (7G8)
Live, infectious, aseptic, purified, vialed, cryopreserved, Plasmodium falciparum sporozoites, strain 7G8

Other:
• Normal saline
0.9% sodium chloride

Locations

Country	Name	City	State
Germany	Institute of Tropical Medicine, University of Tuebingen, Wilhelmstr. 27	Tübingen

Sponsors (4)

Lead Sponsor	Collaborator
Sanaria Inc.	German Center for Infection Research, German Federal Ministry of Education and Research, Institute of Tropical Medicine, University of Tuebingen

Country where clinical trial is conducted

Germany, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Number or occurrence of at least possibly related Grade 3 AEs and serious adverse events (SAEs) for PfSPZ Vaccine	Number or occurrence of at least possibly related Grade 3 AEs and SAEs from time of first administration of PfSPZ Vaccine to the end of the follow-up period.	Around 14 months (from day of first immunization through study completion)
Primary	PfSPZ Challenge (7G8) dose finding - Number or occurrence of at least possibly related Grade 3 AEs and SAEs	Number or occurrence of at least possibly related Grade 3 AEs and SAEs from time of first administration of PfSPZ Challenge (7G8) to the end of the follow-up period.	Around 140 days (from day of first PfSPZ Challenge (7G8) CHMI through end of follow-up)
Secondary	Number of adverse events following immunization (AEFI) for PfSPZ Vaccine	Number of adverse events following immunization (AEFI) from time of first administration of PfSPZ Vaccine to first administration of PfSPZ Challenge for CHMI consistent with a causal relationship.	About 7 weeks (from day of first vaccination until 3 weeks after last vaccination)
Secondary	Proportion of volunteers who become parasitemic will be recorded, detected by thick blood film microscopy or qPCR	Thick blood film microscopy and quantitative polymerase chain reaction (qPCR) assays will be performed during CHMI follow-up. The proportion of volunteers who become parasitemic will be recorded, detected by thick blood film microscopy or qPCR, within 28 days following CHMI with 3,200 PfSPZ, given either as a single dose of 3,200 PfSPZ Challenge (NF54) (optimization phase) or as two subsequent injections of 3,200 PfSPZ Challenge (NF54) and PfSPZ Challenge (7G8), respectively in the verification phase.	Up to 4 weeks (from day of CHMI until 28 days)
Secondary	Proportion of volunteers who do not become parasitemic (protected) against homologous (NF54) and heterologous (7G8) CHMI, respectively.	This endpoint can only be assessed during the verification phase of the trial.	About 28 days (from day of first CHMI till 28 days)