Veronique Dartois` presentation

Drug penetration into
tuberculous lesions
Véronique DARTOIS
Crick TB Symposium, 24 March 2016
RIF
INH
PZA
EMB
x 2 months +
RIF
INH
x
4 months
= 480 drug*days
pharmacokinetic and pharmacodynamic issues
1. Lesion penetration: Do drugs get
to where they need to act?
PK
2. Persistence: Drug potency in vivo
≠ potency in vitro?
PD
Lesion-centric PK-PD concepts
How much drug does
it take to kill the
resident bugs?
How much drug is there?
concentration
Lesion PK-PD
Concentration over time
in the lung lesion
Potency of Drug against
PK
bacteria present in lesion
PD
Time
Measuring and imaging drug distribution in lesions
In solution digestion
Dissect
Homogenize
Extract
LC/MS/MS
Quantify
c
Drug A Drug B Drug C
Section
TB infected
lung tissue
MALDI-MSI
Image
reconstruction
LC-MS/MS
4 hour gradients
Laser Capture Microdissection
m/z
MALDI Imaging of multiple drugs in a single section
Cellular
rim
2mm
Pyrazinamide
Moxifloxacin
Caseum
Clofazimine
100%
0%
Limit of detection
Distribution of rifampicin in lung lesions
Rifampicin [M-H]
m/z 821
100%
0%
6h after the 7th daily dose
RIF is among the best sterilizing drugs and stays
in caseum until the end of the dosing interval
Cavity
2,500
RIF concentraiton (ng/ml
or ng/g tissue)
RIF [M-H]
m/z 821
Cluster of
nodules
2,000
1,500
1,000
500
0
Rifampicin and Clofazimine at steady state
C
RIF
CASEOUS
NODULES
CFZ
24h post dose
RIFAMPICIN
CLOFAZIMINE
Prideaux et al., Nat Med. 2015
Clofazimine in necrotic nodules and cavities
0%
7,000
6,000
100%
CFZ concentration (ng/ml)
24h post dose at steady state
5,000
cavity wall
cavity caseum
plasma
4,000
3,000
2,000
1,000
0
G105
(20.8h)
NCC01
(26h)
Lenaerts et al., AAC 2014, Efficacy of Clofazimine in C3HeB/FeJ mice
Balb/c
Balb/c
4 week pathology
C3HeB/FeJ
C3HeB/FeJ
7 week pathology
lack of diffusion through caseum correlates with inferior efficacy in Kramnik mice
Lenaerts et al., AAC 2014, Efficacy of Clofazimine in C3HeB/FeJ mice
3 weeks p.i.
C3HeB/FeJ
C3HeB/FeJ ; 3 week pathology
7 weeks p.i.
C3HeB/FeJ; 7 week pathology
the Kramnik mouse model as a useful tool to evaluate drug efficacy against
extracellular bacteria in caseum?
Bactericidal activity of clofazimine
Bacterial load in sputum (CFU/mL)
clofazimine
Diacon et al., AJRCCM 10.1164/rccm.201410-1801OC
Necrotic
nodules
L1 necrotic nod
Cavity
caseum
L4 caseum frm cavity
Cavity
wall
L5 cavity wall
Lung
Plasma
L9 lung
L10 plasma
rifampicin
1: rifampin
1e+01
1e−02
1e−08
L1 necrotic nod
L4 caseum frm cavity
L5 cavity wall
L9 lung
L10 plasma
1: rifampin
pyrazinamide
2: pyrazinamide
2: pyrazinamide
isoniazid
3: isoniazid
Log Concentration (ug/mL)
1e−05
1e+01 100
1e−02
1
1e−08
100
1e+01
1e−01
1
L1 necrotic nod
1e−03
20
0
8
16
24
0
8
16
24
L5 cavity wall
0
8
16
L9 lung
24
0
8
16
L10 plasma
24
0
8
16
Time (hrs)
10
00
80
8
16
24
0
8
16
24
0
8
16
24
0
8
16
24
0
8
16
24
Time (hrs)
kanamycin
5: kanamycin
Log Concentration (ug/mL)
1e−01
1e−03
24
moxifloxacin
4: moxifloxacin
1e+01
L4 caseum frm cavity
3: isoniazid
Log Concentration (ug/mL)
1e−05
60
40
20
0
0
8
16
24
0
8
16
24
0
8
16
24
Time (hrs)
0
8
16
24
0
8
16
24
Sneha GUPTA
Rada SAVIC
UCSF
4 patterns of drug distribution in lesions
Rapid and homogeneous distribution, no accumulation over time
• Small and polar: INH, PZA
• Linezolid
Rapid and heterogeneous distribution, with higher levels in
the cellular rim than in caseum
• Fluoroquinolones
• Oxazolidinones with higher cLogP than linezolid
Slow distribution, with gradual accumulation in caseum
• Rifampicin (but not all rifamycins)
Rapid distribution, with massive accumulation in cellular layers
and poor diffusion into caseum
• Clofazimine
• Diarylquinolines (bedaquiline)
Drug partitioning and emergence of drug resistance
Population 1
Population 2
DRUG
1
Population 3
DRUG 3
DRUG 2
Phenotypic
tolerance
TB lesions may have local and temporal “pockets” of monotherapy
SUMMARY
Approaches to reduce treatment duration
1. Optimize the use of current drugs
2. Rationally design new regimens
– Measure drug exposure at the sites of infection
– Measure drug tolerance of resident bacilli
– Use PK-PD approaches to put it all together
Regimens that have the best chance to reach and
kill all populations, and prevent emergence of
resistance
NIH
Thank you!
Clif Barry
Laura Via
CSU
Anne Lenaerts
JHU
Kelly Dooley
KOREAN PATIENTS
Asan Medical Center
Pusan Natl University
National Medical Center
UCSF
Rada Savic
TB Drug Accelerator
GCGH 11
Douglas Young