Therapeutic drug monitoring (TDM) of poly(ADP-ribose) polymerase inhibitors (PARPis) is an exploratory practice aimed at improving the quality of treatment through personalized therapy. Currently, ...there are 4 European Medicines Agency-approved and US Food and Drug Administration-approved PARPis available clinically whose quantification requires validated analytical methods: olaparib, niraparib, rucaparib, and talazoparib. The purpose of this literature review was to highlight the pharmacological features of PARPis that could support their TDM practice and provide a detailed discussion of the available liquid chromatography coupled with tandem mass spectrometry methods for their quantification.
Using several Medical Subject Heading terms, the literature was searched using several research engines, including SciFinder, Web of Science, Google Scholar, and PubMed, to find articles published before August 2022.
Exposure-efficacy and exposure-safety profiles, drug-drug interactions, and hepatic/renal impairment of PARPis provide the potential rationale to monitor their concentrations through TDM. Several bioanalytical methods for their quantification have been reported and compared, and a great deal of heterogeneity has been found among methods, regarding both their analytical and regulatory aspects.
In addition to reducing toxicity and increasing the efficacy of PARPis therapy, TDM could be beneficial to thoroughly investigate the exposure-response relationships of PARPis and to establish pharmacokinetic thresholds for clinical decisions. Based on the comparison of published bioanalytical methods, their transferability and validation both play a key role in method selection. For future use in clinical TDM, we anticipate that bioanalytical methods should address every analytical need more thoroughly and should be validated with standardized guidelines.
Photoactivatable Pt(IV) prodrugs represent nowadays an intriguing class of potential metal-based drugs, endowed with more chemical inertness in their oxidized form and better selectivity for the ...target with respect to the clinically established Pt(II) compounds. In fact, they have the possibility to be reduced by light irradiation directly at the site of interest. For this reason, we synthesized a new Pt(IV) complex, Pt(OCOCH
)
(4'-phenyl-2,2':6',2''-terpyridine)CF
SO
(
), that is well soluble in aqueous medium and totally unreactive towards selected model biomolecules until its reduction. The highlight of this work is the rapid and efficient photoreduction of
with visible light (460 nm), which leads to its reactive Pt(II) analogue. This behavior was made possible by taking advantage of an efficient catalytic system based on flavin and NADH, which is naturally present in the cellular environment. As a comparison, the reduction of
was also studied with simple UV irradiation, but both UV-Vis spectrophotometry and
H-NMR spectrometry showed that the flavin-catalyzed reduction with visible light was faster. Lastly, the reactivity against two representative biological targets, i.e., human serum albumin and one monofilament oligonucleotide fragment, was evaluated by high-resolution mass spectrometry. The results clearly pointed out that the prodrug
did not interact with these targets until its photoreduction to the Pt(II) analogue.
Lenvatinib (LENVA) is an oral antineoplastic drug used for the treatment of hepatocellular carcinoma and thyroid carcinoma. LENVA therapeutic drug monitoring (TDM) should be mandatory for a precision ...medicine to optimize the drug dosage. To this end, the development of a sensitive and robust quantification method to be applied in the clinical setting is essential. The aim of this work was to develop and validate a sensitive, rapid, and cost-effective LC-MS/MS method for the quantification of LENVA in human plasma. On this premise, sample preparation was based on a protein precipitation and the chromatographic separation was achieved on a Synergi Fusion RP C18 column in 4 min. The method was completely and successfully validated according to European Medicines Agency (EMA) and Food and Drug Administration (FDA) guidelines, with good linearity in the range of 0.50-2000 ng/mL (R≥0.9968). Coefficient of variation (CV) for intra- and inter-day precision was ≤11.3% and accuracy ranged from 96.3 to 109.0%, internal standard normalized matrix effect CV% was ≤2.8% and recovery was ≥95.6%. Successful results were obtained for sensitivity (signal to noise (S/N) ratio >21) and selectivity, dilution integrity (CV% ≤ 4.0% and accuracy 99.9-102%), and analyte stability under various handling and storage conditions both in matrix and solvents. This method was applied to quantify LENVA in patient's plasma samples and covered the concentration range achievable in patients. In conclusion, a sensitive and robust quantification method was developed and validated to be applied in the clinical setting.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The impact of body mass index (BMI) on treatment outcomes in patients with cancer is gaining increasing attention given the limited data available. The aim of this study was to investigate the ...contribution of BMI on the safety and efficacy profile of palbociclib in 134 patients with metastatic luminal-like breast cancer treated with palbociclib and endocrine therapy (ET). Normal-weight and underweight patients (BMI<25) were compared with overweight and obese (BMI≥25). Detailed clinical and demographic data were collected. Patients with a BMI<25 had a higher incidence of relevant-hematologic toxicities (p = 0.001), dose reduction events (p = 0.003), and tolerated lower dose intensities (p = 0.023) compared to patients with a BMI≥25. In addition, patients with a BMI<25 had significantly shorter progression-free survival (log-rank p = 0.0332). A significant difference was observed in the subgroup of patients for whom systemic palbociclib concentrations were available: patients with a BMI<25 had a 25% higher median minimum plasma concentrations (Cmin) compared to BMI≥25. This study provides compelling evidence for a clinically relevant contribution of BMI in discriminating a group of patients who experienced multiple toxicities that appeared to affect treatment adherence and lead to poorer survival. BMI could become a valuable tool for personalizing the starting dose of palbociclib to improve its safety and efficacy.
In this work, we have analysed the binding of the Pt(II) complexes (PtCl(4'-phenyl-2,2':6',2″-terpyridine)(CF
SO
) (
), PtI(4'-phenyl-2,2':6',2″-terpyridine)(CF
SO
) (
) and ...PtCl(1,3-di(2-pyridyl)benzene) (
) with selected model proteins (hen egg-white lysozyme, HEWL, and ribonuclease A, RNase A). Platinum coordination compounds are intensively studied to develop improved anticancer agents. In this regard, a critical issue is the possible role of Pt-protein interactions in their mechanisms of action. Multiple techniques such as differential scanning calorimetry (DSC), electrospray ionization mass spectrometry (ESI-MS) and UV-Vis absorbance titrations were used to enlighten the details of the binding to the different biosubstrates. On the one hand, it may be concluded that the affinity of
for the proteins is low. On the other hand,
and
strongly bind them, but with major binding mode differences when switching from HEWL to RNase A. Both
and
bind to HEWL with a non-specific (DSC) and non-covalent (ESI-MS) binding mode, dominated by a 1:1 binding stoichiometry (UV-Vis). ESI-MS data indicate a protein-driven chloride loss that does not convert into a covalent bond, likely due to the unfavourable complexes' geometries and steric hindrance. This result, together with the significant changes of the absorbance profiles of the complex upon interaction, suggest an electrostatic binding mode supported by some stacking interaction of the aromatic ligand. Very differently, in the case of RNase A, slow formation of covalent adducts occurs (DSC, ESI-MS). The reactivity is higher for the iodo-compound
, in agreement with iodine lability higher than chlorine.
Poly (ADP-ribose) polymerase inhibitors (PARPis) are becoming increasingly meaningful in oncology, and their therapeutic drug monitoring (TDM) might be beneficial for patients. Several bioanalytical ...methods have been reported for PARPis quantification in human plasma, but advantages might be obtained using dried blood spot (DBS) as a sampling technique. Our aim was to develop and validate a liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for olaparib, rucaparib, and niraparib quantification in both human plasma and DBS matrices. Additionally, we aimed to assess the correlation between the drug concentrations measured in these two matrices. DBS from patients was obtained using Hemaxis DB10 for volumetric sampling. Analytes were separated on a Cortecs-T3 column and detected with electrospray ionization (ESI)-MS in positive ionization mode. Validation was performed according to the latest regulatory guidelines, in the range (ng/mL) 140-7000 for olaparib, 100-5000 for rucaparib, and 60-3000 for niraparib, within the hematocrit (Hct) range 29-45%. The Passing-Bablok and Bland-Altman statistical analyses revealed a strong correlation between plasma and DBS for olaparib and niraparib. However, due to the limited amount of data, it was challenging to establish a robust regression analysis for rucaparib. To ensure a more reliable assessment, additional samples are required. The DBS-to-plasma ratio was used as a conversion factor (CF) without considering any patient-related hematological parameters. These results provide a solid basis for the feasibility of PARPis TDM using both plasma and DBS matrices.
A wide inter-individual variability in the therapeutic response to cyclin-dependent kinases 4 and 6 inhibitors (CDKis) has been reported. We herein present a case series of five patients treated with ...either palbociclib or ribociclib referred to our clinical pharmacological counselling, including therapeutic drug monitoring (TDM), pharmacogenetics, and drug–drug interaction analysis to support clinicians in the management of CDKis treatment for metastatic breast cancer. Patients’ plasma samples for TDM analysis were collected at steady state and analyzed by an LC-MS/MS method for minimum plasma concentration (C
min
) evaluation. Under and overexposure to the drug were defined based on the mean C
min
values observed in population pharmacokinetic studies. Polymorphisms in selected genes encoding for proteins involved in drug absorption, distribution, metabolism, and elimination were analyzed (
CYP3A4
,
CYP3A5
,
ABCB1, SLCO1B1
, and
ABCG2
). Three of the five reported cases presented a CDKi plasma level above the population mean value and were referred for toxicity. One of them presented a low function
ABCB1
haplotype (
ABCB1-rs1128503
,
rs1045642
, and
rs2032582
), possibly causative of both increased drug oral absorption and plasmatic concentration. Two patients showed underexposure to CDKis, and one of them was referred for early progression. In one patient, a
CYP3A5*1/*3
genotype was found to be potentially responsible for more efficient drug metabolism and lower drug plasma concentration. This intensified pharmacological approach in clinical practice has been shown to be potentially effective in supporting prescribing oncologists with dose and drug selection and could be ultimately useful for increasing both the safety and efficacy profiles of CDKi treatment.
Background
Chronic oral anticancer therapies, are increasingly prescribed and present new challenges including the enhanced risk of overlooked drug-drug interactions (DDIs). Lengthy treatments and ...patients’ management by different professionals can lead to serious prescribing errors that therapeutic drug monitoring (TDM) can help identifying thus allowing a more effective and safer treatment of patients with polypharmacy.
Objectives
This report aims to exemplify how an intensified pharmacological approach could help in the clinical monitoring of patients on chronic treatments.
Methods
A patient with gastrointestinal stromal tumor was referred to our clinical pharmacology service due to tumor progression while on imatinib therapy. The investigation was based on TDM, pharmacogenetics, DDI evaluation and Circulating tumor DNA (ctDNA) analysis. The patient underwent repeated blood samplings to measure imatinib and norimatinib plasma concentrations through a validated LC-MS/MS method. Polymorphisms affecting genes involved in imatinib metabolism and transport were investigated using SNPline PCR Genotyping System. Drug-drug interactions were evaluated though Lexicomp. ctDNA analysis was performed on MiSeq platform.
Results
TDM analysis revealed that the patient was underexposed to imatinib (C
min
= 406 ng/mL; target C
min
= 1100 ng/mL). Subsequent DDI analysis highlighted a dangerous interaction with carbamazepine, via CYP3A4 and P-gp strong induction, omitted at the time of imatinib treatment start. No relevant pharmacogenetic variants were identified and appropriate compliance to treatment was ascertained. ctDNA monitoring was performed to assess potential tumor-related resistance to imatinib. Carbamazepine was cautiously switched to a non-interacting antiepileptic drug, restoting IMA plasma concentration (i.e. C
min
= 4298 ng/mL). The progression of the disease, which in turn led to the patient’s death, was also witnessed by an increasing fraction of ctDNA in plasma.
Conclusion
The active pharmacological monitoring allowed the identification of a dangerous previously over-looked DDI leading to IMA under-exposure. The switch to a different antiepileptic treatment, reversed the effect of DDI, restoring therapeutic IMA plasmatic concentrations.
Graphical abstract
A new LC-MS/MS method for the quantification of lenvatinib (LENVA) in venous Dried Blood Spot (DBS) samples has been presented. This method is characterized by a short run time (4 min), requires a ...volumetric sampling of 10 µL and extraction of the entire spot to avoid hematocrit (Hct) and spot volume effects. The quantification method was successfully validated in the range of 5.00–2000 ng/mL on two different DBS filter papers (Whatman 31 ET CHR and Whatman 903) according to European Medicines Agency (EMA) and Food and Drug Administration (FDA) guidelines, European Bioanalysis Forum (EBF), and International Association of Therapeutic Drug Monitoring and Clinical Toxicology (IATDMCT) recommendations. During the validation process, the following parameters were evaluated: recovery (≥ 77% for both filter papers), absence of matrix effect, process efficiency (close to 72% for Whatman 31 ET CHR and close to 77% for Whatman 903), Hct effect (CV ≤ 6.3% and accuracy within 96–112%), linearity (r ≥ 0.998 for Whatman 31 ET CHR and r ≥ 0.999 for Whatman 903), intra- and inter-day precision (CV ≤ 8.8%) and accuracy (92.8–108%), selectivity and sensitivity, reproducibility with incurred samples reanalysis (ISR), and stability. This method was applied to quantify venous DBS samples from patients with hepatocellular carcinoma treated with LENVA enrolled in a cross-validation study (CRO-2018–83). A good correlation between LENVA plasma concentration determined by standard procedure and the new developed DBS LENVA method (R2 ≥ 0.996) has been observed.
•The first LC-MS method for the quantification of lenvatinib in DBS matrix has been developed.•The method has been fully validated according to FDA, EMA, and IATDMCT guidelines.•DBS is a non-invasive sampling method that may improve TDM application in a cost-effective manner.•A preliminary clinical validation was performed and showed very promising results.
Daratumumab, a pivotal treatment for multiple myeloma, exhibits considerable inter-patient variability in pharmacological clinical outcomes, likely attributed to serum concentration that may ...underscore the need for its therapeutic drug monitoring. This study aims to develop and validate a straightforward analytical method for quantifying daratumumab in serum, focusing on intact light chain determination, using liquid chromatography high-resolution mass spectrometry. The sample preparation involved immunoglobulin enrichment using Melon gel followed by a reduction step to dissociate the light from the heavy chains of immunoglobulins. The latter were then separated using a MabPac RP 2.1 × 50 mm chromatographic column and the intact light chains were detected and quantified using a Q Exactive Orbitrap mass spectrometer operating in ESI-positive ion mode at 17 500 resolution. The method demonstrated excellent linearity (
> 0.992) across a serum concentration range of 100 to 2000 μg mL
and good precision and accuracy: intra- and interday relative errors ranged from -5.1% to 6.5%, with a relative standard deviation of less than 5.8%. Clinical suitability was confirmed by analyzing 80 clinical samples from multiple myeloma patients treated with 1800 mg of daratumumab. 99% of the samples fell within the analytical range with a mean daratumumab concentration evaluated before the next administration (
) of 398 μg mL
. These findings highlighted that intact light chain monoclonal antibody quantification could be a valid and robust alternative to either immunoassays or to LC-MS/MS targeting peptides for measuring daratumumab in clinical samples, positioning it as a suitable method for therapeutic drug monitoring applications.