infiltration of vrc01 into the cerebrospinal fluid in · cerebrospinal fluid plasma cerebrospinal...

Madhu Prabhakaran1, Sandeep Narpala1, Lucio Gama1, Donn J. Colby2,3, Phillip Chan2, Carlo Sacdalan2, Khunthalee Benjapornpong2, Jintanat Ananworanich2,3, Nittaya Phanupak2, Suteeraporn Pinyakorn3, Trevor A. Crowell3, Serena Spudich4, Adrian B McDermott1 on

behalf of the RV397 study team

Conclusions• One of the strategies to accomplishing eradication of HIV latent

reservoirs in the central nervous system (CNS) is to achievedelivery of vaccine candidates past the BBB into the CSF.

• We report here the successful quantification of the bNab VRC01 inCSF from 3 people living with HIV from the RV397 trial whoreceived VRC01 during ATI.

• This detection of VRC01 in CSF is a significant milestone infighting HIV that illustrates the infiltration and bioavailability of thisrelevant bNab in the CNS.

• These results thus serve to inform the design of immunotherapiesto target HIV infection in the CNS.

Future Directions

• Measurement of VRC01 class bNabs in the CSF compartmentare being planned for additional studies (samples from ThaiRV398 study, ACTG studies, etc.).

• PK modelling of relationship between blood and CSF penetrationof VRC01 is being evaluated.

• Potential insight obtained from the AMP trials regardingtherapeutic levels of VRC01 needed to neutralize HIV in plasmamay be used to model levels of bNab required in the CSF toneutralize virus.

References1. Mechanism of Neutralization by the Broadly Neutralizing HIV-1

Monoclonal Antibody VRC01 (Journal of Virology, Aug 2011, 85 (17) 8954-8967)

2. 2. Safety and efficacy of VRC01 broadly neutralising antibodies in adults with acutely treated HIV (RV397): a phase 2, randomised, double-blind, placebo-controlled trial (The Lancet HIV, May 2019, 6 (5), 297-306)

Acknowledgements We would like to thank the study participants who committed so much of their time for this study. Theparticipants were from the RV397 study, which is supported by cooperative agreements (WW81XWH-18-2-0040) between the Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc.,and the U.S. Department of Defense (DOD) and by an intramural grant from the Thai Red Cross AIDSResearch Centre. This research was funded, in part, by the U.S. National Institutes of Health: NIAID,NINDS (R01NS084911), and NIMH support of the International NeuroHIV Cure Consortium.Antiretroviral therapy was supported by the Thai Government Pharmaceutical Organization, Gilead,Merck, and ViiV Healthcare.

DisclaimersThe content of this manuscript is solely the responsibility of the authors and does not necessarilyrepresent the official views of any of the institutions mentioned above, the U.S. Department of the Armyor the U.S. Department of Defense, the Henry M. Jackson Foundation for the Advancement of MilitaryMedicine, the National Institutes of Health, the Department of Health and Human Services, or the UnitedStates government, nor does mention of trade names, commercial products, or organizations implyendorsement by the Thai Red Cross AIDS Research Centre. The investigators have adhered to thepolicies for protection of human participants as prescribed in AR-70-25.

Results

1Vaccine Research Center, National Institutes of Health, USA; 2SEARCH - Thai Red Cross AIDS Research Centre, Thailand; 3US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA; 4Yale University, USA

INFILTRATION OF VRC01 INTO THE CEREBROSPINAL FLUID IN HUMANS IN THE RV397 STUDY

Background• Persistence of HIV infection in the neurological compartments

may continue despite the use of suppressive antiretroviraltherapy (ART), creating a barrier to HIV eradication.

• Novel strategies to reduce the latent HIV reservoir may need tocross the blood brain barrier (BBB) into the cerebrospinal fluid(CSF).

• Targeting the CD4 binding site, VRC01 is a broadly neutralizingantibody (bNab) capable of potently neutralizing over 90% ofHIV-1 strains1.

• We wanted to measure the infiltration of VRC01 into the CSFfollowing passive immunization.

MethodsStudy:The RV397/SEARCH024 Thai VCR01 efficacy study was arandomized, double-blind, placebo-controlled trial of participantswho initiated during acute HIV infection followed by at least 24months of sustained ART. Participants were randomized toreceive VRC01 40 mg/kg (n=13) or placebo (n=5) intravenouslyevery 3 weeks during analytic interruption (ATI) of ART2. CSFcollection was an optional procedure for study participants.Participants:CSF samples were collected at two time points from 3 participantswho received VRC01: pre-ATI/pre-VRC01 infusion and 2-4 daysafter first detectable plasma viral load during ATI.Method:VRC01 levels were quantified using a standardized sensitiveSingulex single molecule counting technology with a lower limit ofquantitation (LLOQ) of 50pg/ml for VRC01. CSF VRC01concentration was compared to concurrent plasma level for eachparticipant. Total IgG levels in plasma and CSF samples weremeasured using ELISA.

CROI 2020 March 8-11Boston, MA 0453

Madhu Prabhakaran1, Sandeep Narpala1, Lucio Gama1, Donn J. Colby2,3, Phillip Chan2, Carlo Sacdalan2, Khunthalee Benjapornpong2, Jintanat Ananworanich2,3, NittayaPhanupak2, Suteeraporn Pinyakorn3, Trevor A. Crowell3, Serena Spudich4, Adrian B McDermott1 on behalf of the RV397 study team

Figure 1: Schematic of the Singulex VRC01 quantitation assay VRC01 is captured by 5C9-coated magnetic beads and detected using Ax647-conjugated anti-human IgG. Fluorescence is read by the Singulex xPro instrument

Plasma

CSF

Donor 3799Donor 5040Donor 3500

0 10 20 30 40 50 60 70 800.1

1

10

100

1000

Day

VRC0

1 ug

/ml

Plasma draw

CSF draw

ATI

Last VRC01 infusion

First detectable viral load

2B.

Figure 2: 2A, 2B. VRC01 levels measured in the CSF and plasma of 3 participants who received VRC01 in the RV397 trial 2C. Fold difference in VRC01 levels between the CSF and plasma compartments in the 3 participants 2D. Total IgG levels measured in the CSF and plasma compartments in the 3 participants2E. Proportion of total IgG that is VRC01 in the CSF and plasma compartments

2A.

Summary of Findings• We were able to successfully quantify VRC01 levels in CSF in 3 people living with

HIV who received VRC01 infusion following ATI, thus reporting for the first time the detection of a HIV bNab in this compartment.

• VRC01 levels detected in CSF were on average 1000-fold lower compared to concurrent plasma levels.

• This difference in VRC01 levels can be attributed to the 1000-fold difference in IgG levels between the CSF and plasma compartments.

• On average, 6% of all IgG in the CSF compartment comprised of VRC01, while in the plasma, 2% of all IgG comprised of VRC01.

2C. 2D. 2E.

VRC01 level (µg/mL)

Days between ATI and CSF draw

post first viral rebound

Days between last VRC01

Infusion and CSF draw post first viral rebound

Viral Load

Cerebrospinal Fluid Plasma Cerebrospinal Fluid (HIV-1 RNA copies/mL) Plasma (HIV-1 RNA copies/mL)

Donor IDBefore VRC01 After first viral

reboundBefore VRC01 After first viral



reboundInfusion Infusion Infusion Infusion

3799 Not quantifiable 0.411 Not quantifiable 251.8 16 16 <80 <80 <20 1789



Donor 379

9

Donor 504

0

Donor 350

0100

101

102

103

104

Fold

diff

eren

ce b

etw

een

VR

C01

le

vels

in C

SF

and

plas

ma

CSF

Plasm

a100

101

102

103

104

105

IgG

(ug/

ml)

**

CSF

Plasm

a0

2

4

6

8

10

% Ig

G

*

infiltration of vrc01 into the cerebrospinal fluid in · cerebrospinal fluid plasma cerebrospinal...

Documents