No clinically significant drug interactions between lenalidomide and P‑glycoprotein substrates and inhibitors: results from controlled phase I studies in healthy volunteers

Pharmacokinetics and Safety of Atogepant Co-administered with Quinidine Gluconate in Healthy Participants: A Phase 1, Open-Label, Drug-Drug Interaction Study

Atogepant, an oral calcitonin gene-related peptide receptor antagonist, is approved for the preventive treatment of migraine. Atogepant is a substrate of P-glycoprotein (P-gp), breast cancer resistance protein, organic anion transporting polypeptide transporters, and cytochrome P450 (CYP)3A4 and 2D6. Quinidine is a strong P-gp and CYP2D6 inhibitor. A phase 1 open-label study evaluated the effect of P-gp and CYP2D6 inhibition by quinidine on the pharmacokinetics of atogepant, and the safety and tolerability of atogepant and quinidine gluconate (QG) when co-administered and when given alone in 33 healthy adults. There was no significant change in the atogepant maximum plasma concentration with QG co-administration. The overall systemic exposure, the area under the plasma concentration-time curve (from time 0 to time t or to infinity), of atogepant increased by 25% when co-administered with QG. However, such an increase was not considered clinically relevant. Atogepant did not alter the mean plasma concentration of quinidine at steady state. The incidence of treatment-emergent adverse events (TEAEs) was highest when QG was administered alone (42.4%), which was primarily due to QT prolongation. Most TEAEs reported were mild in severity and resolved within 1-2 days. Co-administration of atogepant with QG did not result in any unexpected tolerability findings in this phase 1 study in healthy participants. The increase in atogepant exposure during QG co-administration could be due to inhibition of CYP2D6 (a minor contributor to atogepant clearance) as well as inhibition of P-gp.

Lenalidomide use in multiple myeloma (Review)

Lenalidomide is a second-generation new immunomodulatory medication used to treat multiple myeloma (MM). Its mechanism of action involves affecting the expression of vascular endothelial growth factor, interleukin-6, cytochrome c, caspase-8, as well as other factors including immunological modulation and the direct killing of cells, among others, rendering it a fundamental medication, useful for the treatment of MM. Combining lenalidomide with other medications such dexamethasone, bortezomib, ixazomib, carfilzomib and daratumumab can markedly alleviate MM. When autologous-hematopoietic stem cell transplantation (ASCT) cannot be utilized to treat newly diagnosed individuals with MM (NDMM), monotherapy maintenance following lenalidomide and dexamethasone may be employed. Following ASCT, single-agent maintenance with lenalidomide can be performed as an additional treatment. The combination of bortezomib and lenalidomide has been demonstrated to be associated with favorable response rates, tolerable toxicity, and therapeutic benefits although caution is warranted to prevent the onset of peripheral neuropathy with its use. A new-generation oral drug with an excellent safety profile, ixazomib, is more practical and therapeutically applicable in relapsed refractory MM. However, the frequent occurrence of cardiovascular events, hematocrit, and infections with it require flexible adjustment in its clinical application. Carfilzomib produces a rapid and profound response in patients with NDMM eligible for transplantation, but its cardiovascular side effects need to be closely monitored. The primary aim of the present review was to examine the pharmacological properties and pharmacokinetics of lenalidomide, as well as the efficacy and safety of lenalidomide-based treatments with reference to data from clinical trials and real-world studies.

Drug-Drug Interactions Involving Dexamethasone in Clinical Practice: Myth or Reality?

Concomitant administration of multiple drugs frequently causes severe pharmacokinetic or pharmacodynamic drug-drug interactions (DDIs) resulting in the possibility of enhanced toxicity and/or treatment failure. The activity of cytochrome P450 (CYP) 3A4 and P-glycoprotein (P-gp), a drug efflux pump sharing localization and substrate affinities with CYP3A4, is a critical determinant of drug clearance, interindividual variability in drug disposition and clinical efficacy, and appears to be involved in the mechanism of numerous clinically relevant DDIs, including those involving dexamethasone. The recent increase in the use of high doses of dexamethasone during the COVID-19 pandemic have emphasized the need for better knowledge of the clinical significance of drug-drug interactions involving dexamethasone in the clinical setting. We therefore aimed to review the already published evidence for various DDIs involving dexamethasone in vitro in cell culture systems and in vivo in animal models and humans.

Integration of healthy volunteers in early phase clinical trials with immuno-oncological compounds

Aim

Traditionally, early phase clinical trials in oncology have been performed in patients based on safety risk-benefit assessment. Therapeutic transition to immuno-oncology may open new opportunities for studies in healthy volunteers, which are conducted faster and are less susceptible to confounders. Aim of this study was to investigate to what extent this approach is utilized and whether pharmacodynamic endpoints are evaluated in these early phase trials. We conducted a comprehensive review of clinical trials with healthy volunteers using immunotherapies potentially relevant for oncology.

Methods

Literature searches according to PRISMA guidelines and after registration in PROSPERO were conducted in PubMed, Embase, Web of Science and Cochrane databases with the cut-off date 20 October 2020, using search terms of relevant targets in immuno-oncology. Articles describing clinical trials with immunotherapeutics in healthy volunteers with a mechanism relevant for oncology were included. “Immunotherapeutic” was defined as compounds exhibiting effects through immunological targets. Data including study design and endpoints were extracted, with specific attention to pharmacodynamic endpoints and safety.

Results

In total, we found 38 relevant immunotherapeutic compounds tested in HVs, with 86% of studies investigating safety, 82% investigating the pharmacokinetics (PK) and 57% including at least one pharmacodynamic (PD) endpoint. Most of the observed adverse events (AEs) were Grade 1 and 2, consisting mostly of gastrointestinal, cutaneous and flu-like symptoms. Severe AEs were leukopenia, asthenia, syncope, headache, flu-like reaction and liver enzymes increase. PD endpoints investigated comprised of cytokines, immune and inflammatory biomarkers, cell counts, phenotyping circulating immune cells and ex vivo challenge assays.

Discussion

Healthy volunteer studies with immuno-oncology compounds have been performed, although not to a large extent. The integration of healthy volunteers in well-designed proof-of-mechanism oriented drug development programs has advantages and could be pursued more in the future, since integrative clinical trial protocols may facilitate early dose selection and prevent cancer patients to be exposed to non-therapeutic dosing regimens.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=210861, identifier CRD42020210861

Drug and Solute Transporters in Mediating Resistance to Novel Therapeutics in Multiple Myeloma

Multiple myeloma remains an incurable malignancy of plasma cells. Novel therapies, notably proteasome inhibitors and immunomodulatory drugs, have improved the survival of multiple myeloma patients; however, patients either present with, or develop resistance to, these therapies. Resistance to traditional chemotherapeutic agents can be caused by cellular drug efflux via adenosine triphosphate (ATP)-binding cassette (ABC) transporters, but it is still not clear whether these transporters mediate resistance to proteasome inhibitors and immunomodulatory drugs in multiple myeloma. Solute carrier (SLC) transporters also play a role in cancer drug resistance due to changes in cell homeostasis caused by their abnormal expression and changes in the solutes they transport. In this review, we evaluate resistance to novel therapies used to treat multiple myeloma, as mediated by drug and solute transporters.

Multiple Myeloma: Available Therapies and Causes of Drug Resistance

Multiple myeloma (MM) is the second most common blood cancer. Treatments for MM include corticosteroids, alkylating agents, anthracyclines, proteasome inhibitors, immunomodulatory drugs, histone deacetylase inhibitors and monoclonal antibodies. Survival outcomes have improved substantially due to the introduction of many of these drugs allied with their rational use. Nonetheless, MM patients successively relapse after one or more treatment regimens or become refractory, mostly due to drug resistance. This review focuses on the main drugs used in MM treatment and on causes of drug resistance, including cytogenetic, genetic and epigenetic alterations, abnormal drug transport and metabolism, dysregulation of apoptosis, autophagy activation and other intracellular signaling pathways, the presence of cancer stem cells, and the tumor microenvironment. Furthermore, we highlight the areas that need to be further clarified in an attempt to identify novel therapeutic targets to counteract drug resistance in MM patients.

Influence of ABCB1 polymorphisms on the pharmacokinetics and toxicity of lenalidomide in patients with multiple myeloma

Individual diversity in plasma concentrations of lenalidomide occurs despite dosage modifications based on creatinine clearance (CCr), which can lead to unexpected toxicity. We have previously identified a cutoff value of area under the concentration-time curve (AUC_0-24) for lenalidomide to avoid severe toxicity. Here, we investigated the association between ABCB1 polymorphisms and pharmacokinetics of lenalidomide in patients with multiple myeloma (MM) treated with lenalidomide and dexamethasone. Plasma concentrations of lenalidomide were analyzed using liquid chromatography-tandem mass spectrometry. Genotyping for ABCB1 1236C>T, 2677G>A/T, and 3435C>T polymorphisms was performed, and the effects of ABCB1 polymorphisms on AUC_0-24 for lenalidomide were compared in 36 patients with MM who were administered lenalidomide according to the drug label based on CCr. Genotyping analysis showed that although there were no differences in AUC_0-24 in 1236C>T and 2677G>A/T polymorphisms. AUC_0-24 was significantly higher in patients with the T allele of 3435C>T (n = 15) than in those without (n = 21) (median 6324.6 ng h/mL vs. 2857.4 ng h/mL, p = 0.028). The AUC_0-24 value exceeded the aforementioned cutoff value in 95% of the patients with the T allele of 3435C>T but in 60% with C/C genotype (p = 0.013). Multivariate logistic analysis confirmed the significance of T allele of ABCB1 3435C>T as a factor due to which the AUC_0-24 cutoff value was exceeded (hazard ratio of 15.0, p = 0.019). We show that lenalidomide pharmacokinetics is influenced by the ABCB1 3435C>T polymorphism, which could be useful to individualize dosage design and reduce unexpected toxicity.

Phase 1 investigation of lenalidomide/rituximab plus outcomes of lenalidomide maintenance in relapsed CNS lymphoma

There is an unmet need for effective biological therapies for relapsed central nervous system (CNS) lymphoma. Lenalidomide is active in activated B-cell type diffuse large B-cell lymphoma and rituximab is effective in CNS lymphoma. These observations are the basis for this first trial of an immunomodulatory drug as monotherapy in CNS lymphoma, and, in patients with inadequate responses to lenalidomide, with rituximab. In an independent cohort, we evaluated lenalidomide maintenance after salvage with high-dose methotrexate or focal irradiation in relapsed primary CNS lymphoma (PCNSL). We determined safety, efficacy, and cerebrospinal fluid (CSF) penetration of lenalidomide at 10-, 15-, and 20-mg dose levels in 14 patients with refractory CD20⁺ CNS lymphoma. Nine subjects with relapsed, refractory CNS lymphoma achieved better than partial response with lenalidomide monotherapy, 6 maintained response ≥9 months, and 4 maintained response ≥18 months. Median progression-free survival for lenalidomide/rituximab was 6 months. In the independent cohort, response duration with lenalidomide maintenance after complete responses 2 through 5 were significantly longer than response durations after standard therapy. The CSF/plasma partition coefficient of lenalidomide was ≥20% at 15- and 20-mg dose levels. Change in CSF interleukin-10 at 1 month correlated with clinical response and response duration to lenalidomide. Metabolomic profiling of CSF identified novel biomarkers, including lactate, and implicated indoleamine-2,3 dioxygenase activity with CNS lymphoma progression on lenalidomide. We conclude that lenalidomide penetrates ventricular CSF and is active as monotherapy in relapsed CNS lymphomas. We provide evidence that maintenance lenalidomide potentiates response duration after salvage in relapsed PCNSL and delays whole brain radiotherapy (WBRT). This trial was registered at www.clinicaltrials.gov as #NCT01542918.

Population pharmacokinetics of lenalidomide in patients with B-cell malignancies

AIMS

Lenalidomide is an immunomodulatory imide drug used broadly in the treatment of multiple myeloma and lymphoma. It continues to be evaluated in chronic lymphocytic leukaemia (CLL) at lower doses due to dose-related toxicities including tumour flare and tumour lysis syndrome. This study aimed to develop a population pharmacokinetic model for lenalidomide in multiple cancers, including CLL, to identify any disease-related differences in disposition.

METHODS

Lenalidomide concentrations from 4 clinical trials were collated (1999 samples, 125 subjects), covering 4 cancers (multiple myeloma, CLL, acute myeloid leukaemia and acute lymphoblastic leukaemia) and a large dose range (2.5-75 mg). A population pharmacokinetic model was developed with NONMEM and patient demographics were tested as covariates.

RESULTS

The data were best fitted by a 1-compartment kinetic model with absorption described by 7 transit compartments. Clearance and volume of distribution were allometrically scaled for fat-free mass. The population parameter estimates for apparent clearance, apparent volume of distribution and transit rate constant were 12 L/h (10.8-13.6), 68.8 L (61.8-76.3), and 13.5 h^-1 (11.9-36.8) respectively. Patients with impaired renal function (creatinine clearance <30 mL/min) exhibited a 22% reduction in lenalidomide clearance compared to patients with creatinine clearance of 90 mL/min. Cancer type had no discernible effect on lenalidomide disposition.

CONCLUSIONS

This is the first report of a lenalidomide population pharmacokinetic model to evaluate lenalidomide pharmacokinetics in patients with CLL and compare its pharmacokinetics with other B-cell malignancies. As no differences in pharmacokinetics were found between the observed cancer-types, the unique toxicities observed in CLL may be due to disease-specific pharmacodynamics.

Clinical pharmacokinetics of oral drugs in the treatment of multiple myeloma

Treatment of myeloma is a long-term treatment mainly based on all-oral combinations of drugs. Because oral drugs have a more complex pharmacokinetics compared with IV treatments, an appropriate knowledge of the factors that may alter their systemic exposure is of particular clinical relevance. Both drug-drug interactions, food-effect, and dose-adaptation in renal and hepatic impairment may influence the systemic drug levels with a potential impact on drug efficacy or safety. Moreover, a better control of drug exposure may improve the side effect profiles of these treatments with a favourable impact on patient compliance. Furthermore, as long-term treatments, these drugs may also alter the systemic exposure of coadministered medications in these rather old patients. The aim of this review was to identify the factors modifying the systemic exposure of oral drugs used in myeloma by focusing on the pharmacokinetic drug-drug interactions and the effects of renal and hepatic impairment and of food impact.

Pharmacogenetic study of the impact of ABCB1 single-nucleotide polymorphisms on lenalidomide treatment outcomes in patients with multiple myeloma: results from a phase IV observational study and subsequent phase II clinical trial

PURPOSE

Despite therapeutic advances, patients with multiple myeloma (MM) continue to experience disease relapse and treatment resistance. The gene ABCB1 encodes the drug transporter P-glycoprotein, which confers resistance through drug extrusion across the cell membrane. Lenalidomide (Len) is excreted mainly via the kidneys, and, given the expression of P-gp in the renal tubuli, single-nucleotide polymorphisms (SNPs) in the ABCB1 gene may influence Len plasma concentrations and, subsequently, the outcome of treatment. We, therefore, investigated the influence of ABCB1 genetic variants on Len treatment outcomes and adverse events (AEs).

METHODS

Ninety patients with relapsed or refractory MM, who received the second-line Len plus dexamethasone in the Rev II trial, were genotyped for the ABCB1 SNPs 1199G>A (Ser400Asn, rs2229109), 1236C>T (silent, rs1128503), 2677G>T/A (Ala893Ser, rs2032582), and 3435C>T (silent, rs1045642) using pyrosequencing, and correlations to response parameters, outcomes, and AEs were investigated.

RESULTS

No significant associations were found between genotype and either best response rates or hematological AEs, and 1236C>T, 2677G>T or 3435C>T genotypes had no impact on survival. There was a trend towards increased time to progression (TTP) in patients carrying the 1199A variant, and a significant difference in TTP between genotypes in patients with standard-risk cytogenetics.

CONCLUSIONS

Our findings show a limited influence of ABCB1 genotype on lenalidomide treatment efficacy and safety. The results suggest that 1199G>A may be a marker of TTP following Len treatment in standard-risk patients; however, larger studies are needed to validate and clarify the relationship.

Population Pharmacokinetics of Lenalidomide in Healthy Volunteers and Patients With Hematologic Malignancies

A population pharmacokinetic (PopPK) model of lenalidomide was developed using data pooled from 13 clinical studies (dose range, 5-400 mg) in participants who were considered to have adequate capability for renal excretion of lenalidomide (creatinine clearance [CrCl] > 50 mL/min). The analysis population included 305 healthy volunteers and 83 patients with multiple myeloma or myelodysplastic syndromes. A 1-compartment model with linear absorption and elimination described well the observed data for both healthy volunteers and patients. Covariate analysis suggested lenalidomide apparent clearance was positively correlated with CrCl, and lenalidomide volume of distribution was positively correlated with body weight. Both pharmacokinetic parameters were reduced by 29% in patients, independent of the effect of CrCl or body weight. Despite their statistical significance, effects of study population and body weight are considered clinically unimportant in adult patients with CrCl > 50 mL. After accounting for the above effects, body weight had no significant effect on CL/F, whereas age, sex, race, and mild hepatic impairment had no significant effect on either lenalidomide parameter. The PopPK model should be useful for future modeling of lenalidomide pharmacokinetics in the pediatric population and for further comparison of pharmacokinetic properties among structurally similar immunomodulatory drugs.

Clinical Pharmacokinetics and Pharmacodynamics of Lenalidomide

Lenalidomide is a lead therapeutic in multiple myeloma and deletion 5q myelodysplastic syndromes and shows promising activities in other hematologic malignancies. This article presents a comprehensive review of the clinical pharmacokinetics and pharmacodynamics of lenalidomide. Oral lenalidomide is rapidly and highly absorbed (>90 % of dose) under fasting conditions. Food affects oral absorption, reducing area under the concentration-time curve (AUC) by 20 % and maximum concentration (C max) by 50 %. The increase in AUC and C max is dose proportional, and interindividual variability in plasma exposure is low to moderate. Lenalidomide distributes into semen but is undetectable 3 days after stopping treatment. Biotransformation of lenalidomide in humans includes chiral inversion, trivial hydroxylation, and slow non-enzymatic hydrolysis. Approximately 82 % of an oral dose is excreted as lenalidomide in urine within 24 h. Lenalidomide has a short half-life (3-4 h) and does not accumulate in plasma upon repeated dosing. Its pharmacokinetics are consistent across patient populations, regardless of the type of hematologic malignancy. Renal function is the only important factor affecting lenalidomide plasma exposure. Lenalidomide has no QT prolongation risk at approved doses, and higher plasma exposure to lenalidomide is associated with increased risk of neutropenia and thrombocytopenia. Despite being a weak substrate of P-glycoprotein (P-gp) in vitro, lenalidomide does not have clinically significant pharmacokinetic interactions with P-gp substrates/inhibitors in controlled studies. The AUC-matched dose adjustment is recommended for patients with renal impairment at the start of therapy. No dose adjustment for lenalidomide is needed on the basis of age, ethnicity, mild hepatic impairment, or drug-drug interactions.

Phase II Trial of Lenalidomide in HIV-Infected Patients with Previously Treated Kaposi's Sarcoma: Results of the ANRS 154 Lenakap Trial

Lenalidomide, an oral immunomodulating agent, has shown promising activity in HIV-infected individuals with Kaposi's sarcoma (KS). This single-arm, multicenter, open-label, Gehan's two-stage phase II trial evaluated the efficacy and safety of lenalidomide in HIV-infected patients with progressive KS despite previous chemotherapy (NCT01282047, ANRS 154 Lenakap trial). The primary endpoint was the rate of partial response (PR) or complete response (CR) at week 24, evaluated by both the study investigators and the patients using the Physical Global Assessment (PGA). AIDS Clinical Trials Group (ACTG) criteria for KS treatment evaluation were used as a secondary endpoint. The data and safety monitoring board recommended that enrollments be halted on April 24, 2013, because of lack of responses. We enrolled 12 antiretroviral-treated HIV-infected men with progressive KS despite previous chemotherapy. Their HIV plasma viral load was <50 copies/ml and their median CD4 cell count 444/mm³. One patient stopped taking lenalidomide because of hives at week 1 and a second patient died at week 7. The remaining 10 patients were assessable at week 24, when none had PGA-defined CR or PR and one had ACTG-defined PR. There were no additional PGA responses at week 48, but an additional three patients had ACTG responses, for a total of four patients with ACTG PR at week 48 (40%; 95% confidence interval: 12.2-73.8). Fourteen grade 3-4 adverse events were considered at least possibly related to lenalidomide during a total of 101 cycles. Lenalidomide was well tolerated in antiretroviral experienced patients with progressive KS previously treated with chemotherapy. The ACTG-defined response rate at week 48 was 40%, while it was 0% using PGA criteria.

Evaluation of pharmacokinetic and pharmacodynamic interactions when lenalidomide is co-administered with warfarin in a randomized clinical trial setting

BACKGROUND AND OBJECTIVE

Lenalidomide is an oral immunomodulatory drug used to treat multiple myeloma and some other hematological malignancies. Warfarin is often used concomitantly as prophylaxis against potential venous thromboembolism associated with lenalidomide treatment. The objective of this study was to evaluate the pharmacokinetic and pharmacodynamic drug interactions between lenalidomide and warfarin in healthy volunteers.

METHODS

This was a double-blind, placebo-controlled, randomized, two-period crossover study. Eighteen healthy male and female subjects were treated with 10 mg/day lenalidomide or placebo for 9 days. A single oral 25 mg dose of warfarin was administered on Day 4 of each treatment period. Blood was sampled to determine international normalized ratio (INR), prothrombin time (PT), and area under the plasma concentration-time curve (AUC) and maximum plasma concentration (C max) warfarin and lenalidomide.

RESULTS

The 90 % confidence intervals (CI) for the ratio of AUC or Cmax geometric means between co-administration with lenalidomide and placebo were within the 80-125 % bioequivalence bounds for R-warfarin and S-warfarin. The 90 % CI for the ratio of area under the INR curve from time zero until 144 hours after dosing (AUCINR, 0-144) or the peak INR geometric means between co-administration with lenalidomide versus placebo was also within the 85-125 % bounds. Additionally, the AUC and C max values of lenalidomide were not altered by co-administration with warfarin.

CONCLUSION

Co-administration of lenalidomide with warfarin did not alter the plasma exposure or anticoagulant effect to warfarin or the plasma exposure to lenalidomide, indicating that no dose adjustment of either drug is needed when these two drugs are co-administered.

Alternative matrices for therapeutic drug monitoring of immunosuppressive agents using LC-MS/MS

Immunosuppressive drugs used in solid organ transplants typically have narrow therapeutic windows and high intra- and intersubject variability. To ensure satisfactory exposure, therapeutic drug monitoring (TDM) plays a pivotal role in any successful posttransplant maintenance therapy. Currently, recommendations for optimum immunosuppressant concentrations are based on blood/plasma measurements. However, they introduce many disadvantages, including poor prediction of allograft survival and toxicity, a weak correlation with drug concentrations at the site of action and the invasive nature of the sample collection. Thus, alternative matrices have been investigated. This paper reviews tandem-mass spectrometry (LC-MS/MS) methods used for the quantification of immunosuppressant drugs utilizing nonconventional matrices, namely oral fluids, fingerprick blood and intracellular and intratissue sampling. The advantages, disadvantages and clinical application of such alternative mediums are discussed. Additionally, sample extraction techniques and basic chromatography information regarding these methods are presented in tabulated form.

Front-line lenalidomide therapy in patients with newly diagnosed multiple myeloma

The availability of novel drugs with different and innovative mechanisms of action such as proteasome inhibitors such as bortezomib and immunomdulatory agents as thalidomide and lenalidomide have changed the landscape of the treatment of patients with newly diagnosed multiple myeloma, allowing the development of several new therapeutic regimens both for transplant-eligible and -ineligible patients. Among these new agents, lenalidomide has become one of the most commonly used in these patients. In this article, we review the current state-of-the-art of different induction and maintenance lenalidomide-containing regimens administered in transplant-eligible and -ineligible patients with newly diagnosed multiple myeloma. We also discuss the safety profile and potential long-term side effects of this drug and analyze its utility in certain subgroups of patients like those with high-risk disease or different degrees of renal impairment.