Immune
system
Is designed to
protect the host
from
harmful
foreign
molecules.
Allograft
introduction can
elicit damaging
immune
response.
Immune system include two main arms:
Cell –mediated immunity
Humoral (antibody –mediated immunity)
Come personalizzare il trattamento terapeutico
Farmacodinamica
Eventi avversi
Nefro- ,
neurotossicità
ipercolestrolemia
Over immunosuppression
Efficacia del trattamento
Rigetto acuto
Rigetto cronico
Tolleranza
Azione sui recettori
IL2
Linfociti CD+4
Cylex assay
Metodi Analitici
Farmacogenetica
Immunoassays
Proteomica, metabolomica LC-MSMS
performances analitiche
(specificity, sensitivity,…)
Farmacocinetica
Dry spot analisi
Posologia
Interazioni farmacologiche
Distribuzione
Metabolismo
Eliminazione
Farmacogenetica
(CYP3A5, P-gp,…)
Farmaci utilizzati per prevenire il rigetto
d’organo
Steroidi
Anticorpi
no TDM
Anti-IL2 receptor (anti-CD25, e.g. Daclizumab, Basiliximab),
anti-CD3 ATG or ALG
no TDM
Azatioprina
no TDM but need check TPMT activity
Inibitori calcioneurina
Ciclosporina Tacrolimus
Inibitori della sintesi delle purine
Micofenolato mofetile
Inibitori del complesso mTOR
Sirolimus, Everolimus
TDM required
TDM recommended
TDM required
Data base di riferimento
della popolazione
ARMONIZZAZIONE
Selezione corretta
del test
di laboratorio
Richiesta appropriata
Valori di
Riferimento
Richiesta
Interpretazione
Corretta interpretazione
dell’informazione
Fase Pre
Analitica
Valutazione delle fonti di
variazione pre analitica
Qualità Pre-analitica
Analisi
Armonizzazione dei test utilizzati
nella pratica clinica
E pratica del controllo di qualità
AN
OUTCOMESBASED
APPROACH TO
CLASSIFYING
TESTING
RELATED
DIAGNOSTIC
ERROR
Drugs used to prevent organ rejection
Calcineurin inhibitors IL2 production
Cyclosporine Tacrolimus
TDM required
Mycophenolate mofetil/sodium
TDM recommended
mTOR inhibitors Sirolimus/everolimus
TDM required
Inibitori
Calcineurina
Attivazione dei recettori
cellule T
Aumento del Ca2+
Calcioneurina
Cyclosporine
Tacrolimus
Release di IL2
Risposta cellulare
mediata
NFATc (Nuclear Factor of Activated T
cells).
Inibitori delle calcioneurine
Ciclosporina e Tacrolimus
inibizione produzione di IL2
Cyclosporine
Pharmacokinetics:
Can be given orally or i.v. infusion
orally (25 or 100 mg) soft gelatin capsules,
microemulsion.
Peak levels is reached after 1– 4 hours,
elimination half life 24 h.
Oral absorption is delayed by fatty meal
(gelatin capsule formulation) Microemulsion
(has higher bioavailability-is not affected by
food)
50 – 60% of cyclosporine accumulates in
blood (erythrocytes – lymphocytes).
metabolized by CYT-P450 system
(CYP3A4).
excreted mainly through bile into faeces,
about 6% is excreted in urine.
Therapeutic Uses:
Organ transplantation (kidney,
liver, heart) either alone or with
other immunosuppressive agents
(Corticosteroids).
Autoimmune disorders (low dose
7.5 mg/kg/d). e.g. endogenous
uveitis, rheumatoid arthritis,
active Crohn’s disease, psoriasis,
psoriasis, nephrotic syndrome,
severe corticosteroid-dependent
asthma, early type I diabetes.
Graft-versus-host disease after
stem cell transplants
Cyclosporine
Adverse Effects (Dosedependent) TDM is essential
Nephrotoxicity
(increased by NSAIDs and
aminoglycosides).
Liver dysfunction
Hypertension, hyperkalemia.
(K-sparing diuretics should not be
used).
Hyperglycemia.
Viral infections (Herpes
cytomegalovirus)
Lymphoma (Predispose recipients
to cancer)
Hirsutism
Neurotoxicity (tremor)
Drug Interactions
Clearance of cyclosporine is
enhanced by co-administration of
CYT p 450 inducers
(Phenobarbitone, Phenytoin &
Rifampin )
® rejection of transplant
Clearance of cyclosporine is
decreased when it is coadministered with erythromycin
or Ketoconazole, Grapefruit juice
® cyclosporine toxicity
Tacrolimus
Pharmacokinetics:
Therapeutic Uses:
Given orally or i.v or topically
(ointment)
Oral absorption is variable and
incomplete, reduced by fat and
carbohydrate meals
Half-life after I.V. form is 9-12
hours.
Highly bound with serum
proteins and concentrated in
erythrocytes.
metabolized by P450 in liver
Excreted mainly in bile and
minimally in urine
USES as cyclosporine
Organ and stem cell
transplantation
Prevention of rejection of
liver and kidney
transplants (with
glucocorticoids).
Atopic dermatitis and
psoriasis (topically)
Tacrolimus
Adverse Effects (Dosedependent) TDM is essential
Nephrotoxicity (more than CsA)
Neurotoxicity (more than CsA)
Hyperglycemia ( require
insulin).
Hperkalemia
Hypertension
Anaphylaxis
Drug interactions as
cyclosporine.
What are the differences
between CsA and TAC
TAC is more favorable than CsA
due to:
— TAC is 10 – 100 times more
potent than CsA in inhibiting
immune responses.
— TAC has decreased episodes of
rejection.
— TAC is combined with lower
doses of glucocorticoids.
But
— TAC is more nephrotoxic and
neurotoxic.
Drugs used to prevent organ rejection
Calcineurin inhibitors
Cyclosporine Tacrolimus
TDM required
Mycophenolate mofetil/sodium
TDM recommended
mTOR inhibitors Sirolimus/everolimus
TDM required
Micofenolato mofetile
E’ un profarmaco
Il MICOENOLATO
MOFETIL E è
idrolizzato a acido
micofenolico
Inibisce la sintesi de
novo delle purine .
È un potente inibitore
dell’ Inosin Mono
Fosfato, cruciale per la
sintesi delle purine
®blocca la
proliferazione delle
cellule T e B inibendo
gli acidi nucleici
È un potente inibitore dell’ InosinMonoFosfato,
cruciale per la sintesi delle purine
Drugs used to prevent organ rejection
Calcineurin inhibitors IL2 production
Cyclosporine Tacrolimus
TDM required
Mycophenolate mofetil/sodium
TDM recommended
mTOR inhibitors Sirolimus/everolimus
TDM required
IL2 action
mTOR
inhibitors
Sirolimus
everolimus
mTOR è una kinasi
essenziale al ciclo
cellulare, DNA repairs, e
espressione proteica
Forma il complesso
FKBP che si lega a
mTOR
(mammalian Target
of Rapamycin).
SRL blocca la
maturazione delle cellule
T attivate da G1 a S
Non blocca la produzione di IL-2
ma blocca la risposta delle cellule T alle citochine
Sirolimus
Pharmacokinetics:
Given orally and topically,
reduced by fat meal
extensively bound to plasma
proteins
metabolized by CYP3A4 in
liver
excreted in feces
Therapeutic Uses:
Solid organ allograft
Renal transplantation alone or
combined with (CSA,
tacrolimus, steroids,
mycophenolate)
Heart allografts
In halting graft vascular
disease.
Hematopoietic stem cell
transplant recipients
Topically with cyclosporine in
uveoretinitis
Synergistic action with CsA
Drug Interactions With Sirolimus
— As sirolimus is metabolized by the same pathway as the
calcineurin inhibitors CNIs (P-450 3A4), interactions are the
same
— Sirolimus has been shown to raise blood levels of cyclosporine
and MMF
Sirolimus should be administered 4 hours after cyclosporine or
tacrolimus
— Sirolimus blood levels are raised by cyclosporine
Proper monitoring is advised
Side Effects of Sirolimus
Drug and Side Effects
Hypercholesterolemia
Hypertriglyceridemia
Hypertension
Rash
Leukopenia
Anemia
Thrombocytopenia
Interstitial pneumonitis
Mouth ulcers
Proteinuria
Edema
Clinical Implications
Pneumonitis occasionally
resolved in
discontinuation of
sirolimus
Clinical pharmacokinetics and
pharmacodynamics of tacrolimus in solid organ
transplantation
Clin Pharmacokinet. 2004;43(10):623-53
.
To date, no studies have correlated
pharmacodynamic marker assay results with
immunosuppressive efficacy, as determined
by allograft outcome
Drugs used to prevent organ rejection
Calcineurin inhibitors
Cyclosporine Tacrolimus
TDM required
Mycophenolate mofetil/sodium
TDM recommended
mTOR inhibitors Sirolimus/everolimus
TDM required
Metabolismo del Micofenolato mofetile, l’inattivo
estere profarmaco dell’ac. micofenolico
MMF, micofenolato
mofetile è un
profarmaco
assorbito nel tratto
gastrointestinale e
idrolizzato nel
momento
presistemico,
determinando
un’alto
biodisponibilità di
acido micofenolico
MPA (90%)
L’ac. micofenolico è
metabolizzato
dall’UDPglucuronosyltransfera
se nel fegato, rene,
intestine nel
composto inattivo 7-Oglucuronide (MPAG)
e per una percentuale
minore nel composto
attivo acyl
glucuronide
(AcMPAG)
I metaboliti dell’ ac.
micofenolico sono
escreti per via renale
MPA e MPAG sono
soggetti al ricircolo
che è responsabile
dal 10 al 60% del
MPA AUC
nell’intervallo
Randomized prospective trials
It was expected that prospective randomized trials
would give the final answer to the question of
whether or not TDM for MMF would be of added
benefit in the treatment of transplant patients.
The first, Adaption de Posologie du MMF en Greffe Renale
(APOMYGRE)
study was a randomized trial, performed in 11 centers in
France
Compared a fixed-dosage (FD) regimen of MMF 2 g/d with a CC
regimen based on MPA AUC measurements (target
concentrations of 40 mg h/L) using a Bayesian estimator in 137
kidney graft recipients who were receiving CsA therapy
Patients in the CC group achieved significantly higher
MPA exposure within the first 3 months after
transplantation and had a significantly lower incidence
of biopsy-proven acute rejection (BPAR; 7.7 versus 24.6%;
P 0.01)
Le Meur Y. et al. Individualized mycophenolate mofetil dosing based
on drug exposure significantly improves patient outcomes after renal transplantation.
Am J Transplant 2007; 7: 2496–2503
The second, fixed-dose versus concentration
controlled (FDCC), study was a much larger study,
including 901 renal transplant recipients from 19 different
countries
van Gelder T, et al. Comparing mycophenolate mofetil regimens for de novo
renal transplant recipients: The fixed-dose concentration-controlled trial.
Transplantation 2008; 86: 1043–1051.
The Fixed Dose–Concentration Controlled (FDCC) study
compared an FD regimen of 2 g of MMF with a CC regimen
based on abbreviated MPA AUC measurements (target
concentrations of 30 to 60 mg h/L) in 901 patients who were
treated with CsA or tacrolimus.
In FDCC, a benefit for a CC approach could not be
demonstrated.
The Third studies the Opticept study
also compared fixed (2 g) and CC dosing of MMF on the basis of MPA predose
trough concentrations (target 12-hour trough concentrations of 1.3 mg/L for
the CsA group and 1.9 mg/L for the tacrolimus group) in 720 patients who
were on either a standard or a reduced dosage of CsA or tacrolimus
Whereas analysis of the intention-to-treat population
demonstrated no benefit of TDM,Whereas analysis of the
intention-to-treat population demonstrated no benefit of
TDM, a post hoc analysis of 590 patients who were treated
with tacrolimus showed that risk for acute rejection was
significantly lower (P 0.001) in patients who achieved target
MPA trough levels of 1.6 mg/L
Gaston RS, et al. Fixed- or controlled-dose mycophenolate mofetil with standard- or reduced-dose
calcineurin inhibitors: The Opticept trial. Am J Transplant 9: 1607-1619, 2009
The two largest of the three randomized, controlled trials
to examine the value of adjusting MPA dosage on the
basis of drug concentrations did not demonstrate a
better composite outcome in terms of acute rejection
incidence, graft loss, death, and MPA discontinuation.
Although these studies clearly confirmed the
relationship between early MPA exposure and the risk
for acute rejection in the first 3 postoperative months
when used in conventional CNI based regimens, less
evidence is available for late acute rejection episodes (3
months), which occur far less frequently.
The conflicting results of three recent large randomized studies that
examined the clinical benefit of therapeutic drug monitoring (TDM) of
mycophenolic acid (MPA) in terms of graft and patient outcome have
rekindled the debate on the role of concentration-controlled (CC) MPA
dosing in solid organ transplantation.
Indications for TDM of MPA
There is insufficient evidence to offer unequivocal guidelines
on the requirement for MPA monitoring in liver, small
bowel. and pancreas transplantation. One rational approach
may be to perform MPA monitoring, when there is:
• an acute or chronic deterioration in graft function
• onset or change of renal, liver, or bowel (dys)function
(including diarrhea, which may be of infective origin
rather than being due to MPA)
• a substantial change in serum albumin concentration
• a clinically indicated change of CNI type or dosing
• use of MMF in primary therapy (without CNI) or
monotherapy
• a change in the exposure to other interacting
medications, in particular oral antibiotics and
rifampicin
Relationship between MPA Exposure and Toxicity.
Adverse effects
The relationship between MPA exposure and adverse events is weak, and
contradictory results have been reported.
In a multivariate analysis of 125 patients who were on tacrolimus therapy, a rise in median total MPA
predose trough concentration of 1 mg/L within 30 days before the clinical event was associated with an
increased risk for anemia (relative risk [RR] 1.62; P 0.001), leucopenia (RR 1.62; P 0.001), diarrhea (RR
1.54; P 0.001), and viral infection (RR 2.71; P 0.001) Borrows R et al Am J Transplant 6: 121-128, 2006
In the three recent prospective, randomized studies (APOMYGRE, FDCC, and
Opticept), no correlation between MPA predose trough concentrations or AUC
and MMF-related adverse events was observed.
The identification of a clear relationship between MPA exposure and toxicity
can be hampered by use of imprecise definitions for:
adverse events, multicausality of adverse effects, including concomitant drugs,
time elapsed between MPA measurement and event, assay used for MPA
quantification,
and
associated
toxicity
profiles
of
concomitant
immunosuppressive medications.
The GRADE approach for tests and strategies: from test
accuracy to patient important outcomes and recommendations
Holger J Schünemann, Reem Mustafa, Nancy Santesso, Jan Brozek, Patrick Bossuyt, Miranda Langendam,
Andrew D Oxman, Karen R Steingart, Tommaso Trenti, Paul Glasziou, Roman Jaeschke, Julia Kreis, Mark
Helfand, Rob Scholten, Anne Rutjes, Gordon H Guyatt for the GRADE Working Group
AUC TDM
AUC TDM
GERARCHIA DEL
PROCESSO DI
VALUTAZIONE EBLM
Le performances analitiche
sono lo step iniziale e parte
della cultura tradizionale
•standardizzazione
•sensibilità
•specificità
•imprecisione …
L’ impatto clinico e gli
outcomes di salute sono
misure complesse da
valutarsi ma fine delle
politiche di governance nel
sistema sanitario
Decisione
Costi Efficacia
Impatto Organizzativo
Impatto Clinico, Impatto
diagnostico Outcomes di salute
Accuratezza diagnostica
Performances analitiche