Pharmacokinetics and tissue disposition of lenalidomide in mice

Systemic and Brain Pharmacokinetics of Milnacipran in Mice: Comparison of Intraperitoneal and Intravenous Administration

Milnacipran is a dual serotonin and norepinephrine reuptake inhibitor, clinically used for the treatment of major depression or fibromyalgia. Currently, there are no studies reporting the pharmacokinetics (PK) of milnacipran after intraperitoneal (IP) injection, despite this being the primary administration route in numerous experimental studies using the drug. Therefore, the present study was designed to investigate the PK profile of IP-administered milnacipran in mice and compare it to the intravenous (IV) route. First a liquid chromatography-mass spectrometry (LC-MS/MS) method was developed and validated to accurately quantify milnacipran in biological samples. The method was used to quantify milnacipran in blood and brain samples collected at various time-points post-administration. Non-compartmental and PK analyses were employed to determine key PK parameters. The maximum concentration (Cmax) of the drug in plasma was at 5 min after IP administration, whereas in the brain, it was at 60 min for both routes of administration. Curiously, the majority of PK parameters were similar irrespective of the administration route, and the bioavailability was 92.5% after the IP injection. These findings provide insight into milnacipran's absorption, distribution, and elimination characteristics in mice after IP administration for the first time and should be valuable for future pharmacological studies.

Lenalidomide Promotes Thrombosis Formation, but Does Not Affect Platelet Activation in Multiple Myeloma

Lenalidomide, a well-established drug for the treatment of multiple myeloma, significantly enhances patients' survival. Previous clinical studies have demonstrated that its main side effect is an increased risk of thrombotic events. However, the underlying mechanism remains unexplored. Therefore, this study aims to elucidate the mechanism and offer insights into the selection of clinical thrombotic prophylaxis drugs. Firstly, we conducted a retrospective analysis of clinical data from 169 newly diagnosed multiple myeloma patients who received lenalidomide. To confirm the impact of lenalidomide on thrombosis formation, FeCl3-induced thrombosis and deep venous thrombosis models in mice were established. To investigate the effects of lenalidomide on platelet function, both in vivo and in vitro experiments were designed. During the follow-up period, 8 patients developed thrombotic events, including 8 venous and 1 arterial. Further investigation using mice models demonstrated that lenalidomide significantly promoted the formation of venous thrombosis, consistent with clinical findings. To elucidate the underlying mechanism, assays were conducted to assess platelet function and coagulation. We observed that lenalidomide did not have any noticeable impact on platelet function, both in vitro and in vivo, while administration of lenalidomide resulted in significant decreases in prothrombin time, thrombin time, and prothrombin time ratio in patients, as well as a remarkable reduction in tail-bleeding time in mice. The administration of lenalidomide had no significant impact on platelet function, which may affect venous thrombus formation by affecting coagulation. Therefore, anticoagulant drugs may be superior to antiplatelet drugs in the selection of clinical thrombus prophylaxis.

Effects of Mouse Kidney Parvovirus on Pharmacokinetics of Chemotherapeutics and the Adenine Model of Chronic Kidney Disease

Mouse kidney parvovirus (MKPV) causes inclusion body nephropathy in severely immunocompromised mice and renal interstitial inflammation in immunocompetent mice. Here we sought to determine the effects of MKPV on pre-clinical murine models that depend on renal function. To assess the effects of MKPV infection on the pharmacokinetics of 2 renally excreted chemotherapeutic agents, methotrexate and lenalidomide, we measured drug concentrations in the blood and urine of MKPV-infected or uninfected immunodeficient NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) and immunocompetent C57BL/6NCrl (B6) female mice. No differences in plasma pharmacokinetics were observed for lenalidomide. However, the AUC of methotrexate was 1.5-fold higher in uninfected NSG mice compared with infected NSG mice, 1.9-fold higher in infected B6 mice compared with uninfected B6 mice, and 4.3-fold higher in uninfected NSG mice compared with uninfected B6 mice. MKPV infection did not significantly affect the renal clearance of either drug. To assess effects of MKPV infection on the adenine diet model of chronic kidney disease, MKPV-infected and uninfected B6 female mice were fed a 0.2% adenine diet, and clinical and histopathologic features of disease were assessed over 8 wk. MKPV infection did not significantly alter urine chemistry results, hemogram findings, or serum concentrations of BUN, creatinine, or symmetric dimethylarginine. However, infection did influence histologic outcomes. As compared with uninfected mice, MKPV-infected mice had more interstitial lymphoplasmacytic infiltrates after 4 and 8 wk of diet consumption and less interstitial fibrosis at week 8. Macrophage infiltrates and renal tubular injury were similar between in infected and uninfected mice. These findings indicate that MKPV infection had minimal effects on the renal excretion of 2 chemotherapeutics and on serum biomarkers of renal function. However, infection significantly influenced two histologic features of the adenine diet model of chronic renal disease. MKPV-free mice are critically important in studies evaluating renal histology as an experimental outcome.

Species Specificity and Selection of Models for Drug Oxidations Mediated by Polymorphic Human Enzymes

Many drug oxygenations are mainly mediated by polymorphic cytochromes P450 (P450s) and also by flavin-containing monooxygenases (FMOs). More than 50 years of research on P450/FMO-mediated drug oxygenations have clarified their catalytic roles. The natural product coumarin causes hepatotoxicity in rats via the reactive coumarin 3,4-epoxide, a reaction catalyzed by P450 1A2; however, coumarin undergoes rapid 7-hydroxylation by polymorphic P450 2A6 in humans. The primary oxidation product of the teratogen thalidomide in rats is deactivated 5'-hydroxythalidomide plus sulfate and glucuronide conjugates; however, similar 5'-hydroxythalidomide and 5-hydroxythalidomide are formed in rabbits in vivo. Thalidomide causes human P450 3A enzyme induction in liver (and placenta) and is also activated in vitro and in vivo by P450 3A through the primary human metabolite 5-hydroxythalidomide (leading to conjugation with glutathione/nonspecific proteins). Species differences exist in terms of drug metabolism in rodents and humans, and such differences can be very important when determining the contributions of individual enzymes. The approaches used for investigating the roles of human P450 and FMO enzymes in understanding drug oxidations and clinical therapy have not yet reached maturity and still require further development. SIGNIFICANCE STATEMENT: Drug oxidations in animals and humans mediated by P450s and FMOs are important for understanding the pharmacological properties of drugs, such as the species-dependent teratogenicity of the reactive metabolites of thalidomide and the metabolism of food-derived odorous trimethylamine to non-odorous (but proatherogenic) trimethylamine N-oxide. Recognized differences exist in terms of drug metabolism between rodents, non-human primates, and humans, and such differences are important when determining individual liver enzyme contributions with substrates in in vitro and in vivo systems.

Low cerebrospinal fluid-to-plasma ratios of orally administered lenalidomide mediated by its low cell membrane permeability in patients with hematologic malignancies

Lenalidomide is a synthetic analog of thalidomide formed by the removal of one keto group (plus the addition of an amino group); it has anti-tumor activities beneficial for the treatment of hematologic malignancies. However, lenalidomide distribution to brain in animal models is reportedly low compared with that of thalidomide. The aim of this study was to evaluate plasma and cerebrospinal fluid concentrations of lenalidomide in three patients with malignant hematologic malignancies. Lenalidomide was detected in plasma from the three Japanese patients 1.5 h following oral administration of 20 mg lenalidomide using liquid chromatography/mass spectrometry, despite the in vitro gastrointestinal permeability of lenalidomide being low. Clinically observed cerebrospinal fluid-to-plasma ratios of lenalidomide were low (1.3-2.4%). Observed influx permeability values for lenalidomide in monkey blood-brain barrier model and human placental cell systems were one order of magnitude lower than those of thalidomide and another second-generation drug, pomalidomide along with a positive permeability control, caffeine. Because of the low cell-barrier permeability of lenalidomide demonstrated in in vitro assays, clinically relevant pharmacokinetic profiles of lenalidomide resulted in low penetrability from plasma into cerebrospinal fluid in patients with hematologic malignancies. Lenalidomide is conclusively suggested to expert its favorable immunomodulatory effects via systemic exposures in the patients.

TNF-α Induces Neutrophil Apoptosis Delay and Promotes Intestinal Ischemia-Reperfusion-Induced Lung Injury through Activating JNK/FoxO3a Pathway

Background

Intestinal ischemia is a common clinical critical illness. Intestinal ischemia-reperfusion (IIR) leads to acute lung injury (ALI), but the causative factors of ALI are unknown. The aim of this study was to reveal the causative factors and mechanisms of IIR-induced lung injury.

Methods

A mouse model of IIR was developed using C57BL/6 mice, followed by detection of lung injury status and plasma levels of inflammatory factors in sham-operated mice and model mice. Some model mice were treated with a tumor necrosis factor-α (TNF-α) inhibitor lenalidomide (10 mg/kg), followed by observation of lung injury status through hematoxylin and eosin staining and detection of neutrophil infiltration levels through naphthol esterase and Ly6G immunohistochemical staining. Additionally, peripheral blood polymorphonuclear neutrophils (PMNs) were cultured in vitro and then stimulated by TNF-α to mimic in vivo inflammatory stimuli; this TNF-α stimulation was also performed on PMNs after knockdown of FoxO3a or treatment with the c-Jun N-terminal kinase (JNK) inhibitor SP600125. PMN apoptosis after stimulation was detected using flow cytometry. Finally, the role of PMN apoptosis in IIR-induced lung injury was evaluated in vivo by detecting the ALI status in the model mice administered with ABT-199, a Bcl-2 inhibitor.

Results

IIR led to pulmonary histopathological injury and increased lung water content, which were accompanied by increased plasma levels of inflammatory factors, with the TNF-α plasma level showing the most pronounced increase. Inhibition of TNF-α led to effective reduction of lung tissue injury, especially that of the damaging infiltration of PMNs in the lung. In vitro knockdown of FoxO3a or inhibition of JNK activity could inhibit TNF-α-induced PMN apoptosis. Further in vivo experiments revealed that ABT-199 effectively alleviated lung injury and decreased inflammation levels by promoting PMN apoptosis during IIR-induced lung injury.

Conclusion

TNF-α activates the JNK/FoxO3a pathway to induce a delay in PMN apoptosis, which promotes IIR-induced lung injury.

Immune-modulatory effects of lenalidomide inhibited the progression of lesions in a vitiligo mouse model

Vitiligo, an autoimmune disorder, is associated with altered cytokine levels and T lymphocytes. Lenalidomide modulates immune system components by altering cytokine production and regulating T-cell stimulation. In this study, effect of lenalidomide was checked on the development of vitiligo lesions, level of various cytokines, and T lymphocytes in the mouse model. The vitiligo mouse model was developed by immunizing C57BL/6 mouse with anti-mouse tyrosine-related protein 2. Lenalidomide was orally given to mice daily, and the effect was observed on the development of vitiligo lesions. The level of T lymphocytes in blood was checked by flow cytometry. Serum cytokine levels were checked by enzyme-linked immunosorbent assay. Vitiligo lesions were found significantly smaller in lenalidomide-treated mice models. It significantly decreased the serum levels of IFN-γ, TNF-α, IL-1β, and IL-6 but elevated the levels of IL-4 and IL-10. It non-significantly elevated CD4⁺ /CD8⁺ T-cell ratio. Lenalidomide had an inhibitory effect on the development of vitiligo lesions in mice models by suppressing the serum level of pro-inflammatory cytokines and increasing anti-inflammatory cytokine levels. It modulated the immune response in vitiligo mice models toward an anti-inflammatory profile suggesting its use in the management of vitiligo.

The neuroprotective action of lenalidomide on rotenone model of Parkinson's Disease: Neurotrophic and supportive actions in the substantia nigra pars compacta

Lenalidomide is a centrally active thalidomide analog that has potent anti-inflammatory and antiangiogenic activities. Currently, it is primarily used in the treatment of multiple myeloma and myelodysplastic syndromes. However, recent studies have revealed in addition to neuroprotection and neuromodulation of lenalidomide. Because of this combination of inflammation and neuro-immunogenic properties, lenalidomide is considered as a high potential compound for the treatment of neurodegenerative diseases. Despite intensive research during the last decade, the role of neurotrophic elements in the effect of lenalidomide is still not well understood. Therefore, in the current study, the effects of lenalidomide on neurodegeneration were investigated in a rotenone model of Parkinson's disease (PD) rat model. The PD rat model was generated by rotenone injection into the substantia nigra pars compacta (SNpc). After validation of the PD model, the rats were treated with lenalidomide (100 mg/kg) for 28 days. Our data shows that lenalidomide alleviated rotenone-induced motor impairments and deficits in dopamine-related behaviors and resulted in increased levels of tumor necrosis factor-α and calcium-binding protein B in the SNpc. Moreover, chronic lenalidomide treatment resulted increase in transforming growth factor immunoreactivity and brain derived neurotrophic factor expression in the SNPc. In addition, chronic treatment mitigated tyrosine hydroxylase expression prevented the rotenone-induced decrease in dopamine levels, and consequently a decrease in caspase-3/9 immunoreactivity. This thus shows that chronic lenalidomide treatment improves neuronal survival. Together with our data demonstrate that lenalidomide, in addition to its anti-inflammatory and immunomodulatory actions, is also capable of increasing neurotrophic factors in the SNpc, thereby preventing rotenone-induced motor impairments.

Optimal route of gold nanoclusters administration in mice targeting Parkinson’s disease

Aim: To explore the optimal route of gold nanoclusters (AuNCs) administration in mice targeting Parkinson’s disease. Materials & methods: Assessing the pharmacokinetic and bioavailability of AuNCs in mice administrated following intravenous, intraperitoneal, gavage and intranasal injection. Investigating the biodistribution of AuNCs in mice by atomic absorption spectrometry and transmission electron microscope. Toxicity assessments of AuNCs were carried out both in cells and in mice. Results: Administration of AuNCs via intraperitoneal injection showed the greatest bioavailability and the longest residence in brain. AuNCs could penetrate blood–brain barrier and be excreted mainly through kidney. No obvious toxicity of AuNCs found in cells and in mice. Conclusion: The optimal route of AuNCs administration in mice targeting Parkinson’s disease is intraperitoneal administration.

Intraperitoneal Route of Drug Administration: Should it Be Used in Experimental Animal Studies?

Intraperitoneal (IP) route of drug administration in laboratory animals is a common practice in many in vivo studies of disease models. While this route is an easy to master, quick, suitable for chronic treatments and with low impact of stress on laboratory rodents, there is a common concern that it may not be an acceptable route for drug administration in experimental studies. The latter is likely due to sparsity of information regarding pharmacokinetics of pharmacological agents and the mechanisms through which agents get systemic exposure after IP administration. In this review, we summarize the main mechanisms involved in bioavailability of IP administered drugs and provide examples of pharmacokinetic profiles for small and large molecules in comparison to other routes of administration. We conclude with a notion that IP administration of drugs in experimental studies involving rodents is a justifiable route for pharmacological and proof-of-concept studies where the goal is to evaluate the effect(s) of target engagement rather than properties of a drug formulation and/or its pharmacokinetics for clinical translation.

Neuroinflammation as a Factor of Neurodegenerative Disease: Thalidomide Analogs as Treatments

Neuroinflammation is initiated when glial cells, mainly microglia, are activated by threats to the neural environment, such as pathogen infiltration or neuronal injury. Although neuroinflammation serves to combat these threats and reinstate brain homeostasis, chronic inflammation can result in excessive cytokine production and cell death if the cause of inflammation remains. Overexpression of tumor necrosis factor-α (TNF-α), a proinflammatory cytokine with a central role in microglial activation, has been associated with neuronal excitotoxicity, synapse loss, and propagation of the inflammatory state. Thalidomide and its derivatives, termed immunomodulatory imide drugs (IMiDs), are a class of drugs that target the 3'-untranslated region (3'-UTR) of TNF-α mRNA, inhibiting TNF-α production. Due to their multi-potent effects, several IMiDs, including thalidomide, lenalidomide, and pomalidomide, have been repurposed as drug treatments for diseases such as multiple myeloma and psoriatic arthritis. Preclinical studies of currently marketed IMiDs, as well as novel IMiDs such as 3,6'-dithiothalidomide and adamantyl thalidomide derivatives, support the development of IMiDs as therapeutics for neurological disease. IMiDs have a competitive edge compared to similar anti-inflammatory drugs due to their blood-brain barrier permeability and high bioavailability, with the potential to alleviate symptoms of neurodegenerative disease and slow disease progression. In this review, we evaluate the role of neuroinflammation in neurodegenerative diseases, focusing specifically on the role of TNF-α in neuroinflammation, as well as appraise current research on the potential of IMiDs as treatments for neurological disorders.

Development of a physiologically based pharmacokinetic model for intravenous lenalidomide in mice

PURPOSE

Lenalidomide is used widely in B-cell malignancies for its immunomodulatory activity. It is primarily eliminated via the kidneys, with a significant proportion of renal elimination attributed to active processes. Lenalidomide is a weak substrate of P-glycoprotein (P-gp), though it is unclear whether P-gp is solely responsible for lenalidomide transport. This study aimed to determine whether the current knowledge of lenalidomide was sufficient to describe the pharmacokinetics of lenalidomide in multiple tissues.

METHODS

A physiologically based pharmacokinetic model was developed using the Open Systems Pharmacology Suite to explore the pharmacokinetics of lenalidomide in a variety of tissues. Data were available for mice dosed intravenously at 0.5, 1.5, 5, and 10 mg/kg, with concentrations measured in plasma, brain, heart, kidney, liver, lung, muscle, and spleen. P-gp expression and activity were sourced from the literature.

RESULTS

The model predictions in plasma, liver, and lung were representative of the observed data (median prediction error 13%, - 10%, and 30%, respectively, with 90% confidence intervals including zero), while other tissue predictions showed sufficient similarity to the observed data. Contrary to the data, model predictions for the brain showed no drug reaching brain tissue when P-gp was expressed at the blood-brain barrier. The data were better described by basolateral transporters at the intracellular wall. Local sensitivity analysis showed that transporter activity was the most sensitive parameter in these models for exposure.

CONCLUSION

As P-gp transport at the blood-brain barrier did not explain the observed brain concentrations alone, there may be other transporters involved in lenalidomide disposition.

Pomalidomide Reduces Ischemic Brain Injury in Rodents

Stroke is a leading cause of death and severe disability worldwide. After cerebral ischemia, inflammation plays a central role in the development of permanent neurological damage. Reactive oxygen species (ROS) are involved in the mechanism of post-ischemic inflammation. The activation of several inflammatory enzymes produces ROS, which subsequently suppress mitochondrial activity, leading to further tissue damage. Pomalidomide (POM) is a clinically available immunomodulatory and anti-inflammatory agent. Prior cellular studies demonstrate that POM can mitigate oxidative stress and lower levels of pro-inflammatory cytokines, particularly TNF-α, which plays a prominent role in ischemic stroke-induced brain damage and functional deficits. To evaluate the potential value of POM in cerebral ischemia, POM was initially administered to transgenic mice chronically over-expressing TNF-α surfactant protein (SP)-C promoter (SP-C/TNF-α mice) to assess whether systemically administered drug could lower systemic TNF-α level. POM significantly lowered serum levels of TNF-α and IL-5. Pharmacokinetic studies were then undertaken in mice to evaluate brain POM levels following systemic drug administration. POM possessed a brain/plasma concentration ratio of 0.71. Finally, rats were subjected to transient middle cerebral artery occlusion (MCAo) for 60 min, and subsequently treated with POM 30 min thereafter to evaluate action on cerebral ischemia. POM reduced the cerebral infarct volume in MCAo-challenged rats and improved motor activity, as evaluated by the elevated body swing test. POM’s neuroprotective actions on ischemic injury represent a potential therapeutic approach for ischemic brain damage and related disorders, and warrant further evaluation.

Crbn I391V is sufficient to confer in vivo sensitivity to thalidomide and its derivatives in mice

Thalidomide and its derivatives, lenalidomide and pomalidomide, are clinically effective treatments for multiple myeloma and myelodysplastic syndrome with del(5q). These molecules lack activity in murine models, limiting investigation of their therapeutic activity or toxicity in vivo. Here, we report the development of a mouse model that is sensitive to thalidomide derivatives because of a single amino acid change in the direct target of thalidomide derivatives, cereblon (Crbn). In human cells, thalidomide and its analogs bind CRBN and recruit protein targets to the CRL4CRBN E3 ubiquitin ligase, resulting in their ubiquitination and subsequent degradation by the proteasome. We show that mice with a single I391V amino acid change in Crbn exhibit thalidomide-induced degradation of drug targets previously identified in human cells, including Ikaros (Ikzf1), Aiolos (Ikzf3), Zfp91, and casein kinase 1a1 (Ck1α), both in vitro and in vivo. We use the Crbn I391V model to demonstrate that the in vivo therapeutic activity of lenalidomide in del(5q) myelodysplastic syndrome can be explained by heterozygous expression of Ck1α in del(5q) cells. We found that lenalidomide acts on hematopoietic stem cells with heterozygous expression of Ck1α and inactivation of Trp53 causes lenalidomide resistance. We further demonstrate that Crbn I391V is sufficient to confer thalidomide-induced fetal loss in mice, capturing a major toxicity of this class of drugs. Further study of the Crbn I391V model will provide valuable insights into the in vivo efficacy and toxicity of this class of drugs.

Association of pharmacokinetic profiles of lenalidomide in human plasma simulated using pharmacokinetic data in humanized-liver mice with liver toxicity detected by human serum albumin RNA

Lenalidomide has been shown to be potentially teratogenic in thalidomide-sensitive animal species. Screening for thalidomide analogs devoid of teratogenicity/toxicity-attributable to drug metabolism and disposition, but having immunomodulatory properties-is a strategic pathway towards development of new anticancer drugs. Plasma concentrations of lenalidomide were investigated in immunodeficient control and humanized-liver mice following oral administration of lenalidomide (50 mg/kg). Plasma concentrations of lenalidomide (1-2 hr after administration) were slightly but significantly higher in humanized-liver mice than in control mice (p < 0.05). Human albumin mRNA, a liver-specific toxicity marker, was found in the blood of humanized-liver mice 24 hr after lenalidomide administration. Simulations of human plasma concentrations of lenalidomide were achieved with simplified physiologically-based pharmacokinetic models in control and humanized-liver mice or by the direct fitting analysis of reported human data, in accordance with reported lenalidomide concentrations after low dose administration in humans. The results indicate that pharmacokinetic profiles of lenalidomide, a compound resulting from introducing one aromatic amino group into thalidomide and removing one keto group, resulted in less species variation in in vivo pharmacokinetics in control and humanized-liver mice and that immunodeficient humanized-liver mice can serve as experimental model animals for human liver injury in drug development at high doses, with human albumin RNA analysis in plasma.

Clec16a, Nrdp1, and USP8 Form a Ubiquitin-Dependent Tripartite Complex That Regulates β-Cell Mitophagy

Mitophagy is a cellular quality-control pathway, which is essential for elimination of unhealthy mitochondria. While mitophagy is critical to pancreatic β-cell function, the posttranslational signals governing β-cell mitochondrial turnover are unknown. Here, we report that ubiquitination is essential for the assembly of a mitophagy regulatory complex, comprised of the E3 ligase Nrdp1, the deubiquitinase enzyme USP8, and Clec16a, a mediator of β-cell mitophagy with unclear function. We discover that the diabetes gene Clec16a encodes an E3 ligase, which promotes nondegradative ubiquitin conjugates to direct its mitophagy effectors and stabilize the Clec16a-Nrdp1-USP8 complex. Inhibition of the Clec16a pathway by the chemotherapeutic lenalidomide, a selective ubiquitin ligase inhibitor associated with new-onset diabetes, impairs β-cell mitophagy, oxygen consumption, and insulin secretion. Indeed, patients treated with lenalidomide develop compromised β-cell function. Moreover, the β-cell Clec16a-Nrdp1-USP8 mitophagy complex is destabilized and dysfunctional after lenalidomide treatment as well as after glucolipotoxic stress. Thus, the Clec16a-Nrdp1-USP8 complex relies on ubiquitin signals to promote mitophagy and maintain mitochondrial quality control necessary for optimal β-cell function.

Targeting Attenuated Interferon-α to Myeloma Cells with a CD38 Antibody Induces Potent Tumor Regression with Reduced Off-Target Activity

Interferon-α (IFNα) has been prescribed to effectively treat multiple myeloma (MM) and other malignancies for decades. Its use has waned in recent years, however, due to significant toxicity and a narrow therapeutic index (TI). We sought to improve IFNα's TI by, first, attaching it to an anti-CD38 antibody, thereby directly targeting it to MM cells, and, second, by introducing an attenuating mutation into the IFNα portion of the fusion protein rendering it relatively inactive on normal, CD38 negative cells. This anti-CD38-IFNα(attenuated) immunocytokine, or CD38-Attenukine™, exhibits 10,000-fold increased specificity for CD38 positive cells in vitro compared to native IFNα and, significantly, is ~6,000-fold less toxic to normal bone marrow cells in vitro than native IFNα. Moreover, the attenuating mutation significantly decreases IFNα biomarker activity in cynomolgus macaques indicating that this approach may yield a better safety profile in humans than native IFNα or a non-attenuated IFNα immunocytokine. In human xenograft MM tumor models, anti-CD38-IFNα(attenuated) exerts potent anti-tumor activity in mice, inducing complete tumor regression in most cases. Furthermore, anti-CD38-IFNα(attenuated) is more efficacious than standard MM treatments (lenalidomide, bortezomib, dexamethasone) and exhibits strong synergy with lenalidomide and with bortezomib in xenograft models. Our findings suggest that tumor-targeted attenuated cytokines such as IFNα can promote robust tumor killing while minimizing systemic toxicity.

Lenalidomide in Relapsed or Refractory Diffuse Large B-Cell Lymphoma: Is It a Valid Treatment Option?

BACKGROUND

Despite the advent of new treatment strategies, many patients with diffuse large B-cell lymphoma (DLBCL) relapse or die of the disease. Prospective clinical trials have demonstrated that lenalidomide is an effective and safe treatment option, especially for non-germinal center B-cell (non-GCB) DLBCL. However, routine clinical data are lacking, which is why we provide the results of the so-far largest relapsed/refractory (R/R) DLBCL real-life analysis.

METHODS

We retrospectively assessed 123 R/R DLBCL patients who received either 15 or 25 mg/day of lenalidomide from January 2006 to January 2015.

RESULTS

During a median follow-up period of 4.5 years, complete remission was achieved in 32% and a partial remission in 33% non-GCB patients compared with 0% and 3% in the GCB group (p < .001 and .001, respectively), with median response durations of 15 and 5 months, respectively (p < .001). Lenalidomide at 25 mg was superior to 15 mg in terms of response (complete remission 21% and partial remission 23% vs. 0% and 8%; p = .007 and .05) and median response duration (10 vs. 4 months; p = .03). Toxicity was limited and reversible. Median progression-free survival differed between non-GCB and GCB patients (37 vs. 30 months; p < .001) and between the two dosages (24 vs. 34 months; p = .002). However, overall survival was similar between the subgroups (38-42 months).

CONCLUSION

We provide evidence that lenalidomide is a valid treatment option for R/R DLBCL, with limited and reversible toxicity, and is more efficient in non-GCB DLBCL and at higher doses.

IMPLICATIONS FOR PRACTICE

Despite the advent of new treatment strategies, many patients with diffuse large B-cell lymphoma (DLBCL) relapse or die of the disease; hence, novel therapeutic approaches are urgently needed. This study confirms that lenalidomide is a valid and well-tolerated treatment option for relapsed/refractory (R/R) DLBCL. Superior outcomes were observed in non-germinal center B-cell (GCB) DLBCL, probably because of inhibition of the nuclear factor-κB pathway. Similarly, high drug doses resulted in greater clinical benefits. Overall, lenalidomide is a suitable therapeutic option for R/R DLBCL, especially in non-GCB DLBCL, and 25 mg/day dosing should be preferred.

[Lenalidomide nephrotoxicity]

The introduction of lenalidomide into the therapeutic arsenal of hematologic malignancies has represented an important step forward in the management of multiple myeloma. However, its use is associated with several toxicities including kidney injury. The present review examines the drug's pharmacokinetics, discusses the main adverse renal effects that are associated with lenalidomide treatment, and makes recommendations for dosage adjustment in patients with underlying renal impairment.

Combination therapy with lenalidomide and nanoceria ameliorates CNS autoimmunity

OBJECTIVE

Multiple sclerosis (MS) is a debilitating neurological disorder involving an autoimmune reaction to oligodendrocytes and degeneration of the axons they ensheath in the CNS. Because the damage to oligodendrocytes and axons involves local inflammation and associated oxidative stress, we tested the therapeutic efficacy of combined treatment with a potent anti-inflammatory thalidomide analog (lenalidomide) and novel synthetic anti-oxidant cerium oxide nanoparticles (nanoceria) in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS.

METHODS

C57BL/6 mice were randomly assigned to a control (no EAE) group, or one of the four myelin oligodendrocyte glycoprotein-induced EAE groups: vehicle, lenalidomide, nanoceria, or lenalidomide plus nanoceria. During a 23 day period, clinical EAE symptoms were evaluated daily, and MRI brain scans were performed at 11-13 days and 20-22 days. Histological and biochemical analyses of brain tissue samples were performed to quantify myelin loss and local inflammation.

RESULTS

Lenalidomide treatment alone delayed symptom onset, while nanoceria treatment had no effect on symptom onset or severity, but did promote recovery; lenalidomide and nanoceria each significantly attenuated white matter pathology and associated inflammation. Combined treatment with lenalidomide and nanoceria resulted in a near elimination of EAE symptoms, and reduced white matter pathology and inflammatory cell responses to a much greater extent than either treatment alone.

INTERPRETATION

By suppressing inflammation and oxidative stress, combined treatment with lenalidomide and nanoceria can reduce demyelination and associated neurological symptoms in EAE mice. Our preclinical data suggest a potential application of this combination therapy in MS.

Lenalidomide reduces microglial activation and behavioral deficits in a transgenic model of Parkinson's disease

BACKGROUND

Parkinson's disease (PD) is one of the most common causes of dementia and motor deficits in the elderly. PD is characterized by the abnormal accumulation of the synaptic protein alpha-synuclein (α-syn) and degeneration of dopaminergic neurons in substantia nigra, which leads to neurodegeneration and neuroinflammation. Currently, there are no disease modifying alternatives for PD; however, targeting neuroinflammation might be a viable option for reducing motor deficits and neurodegeneration. Lenalidomide is a thalidomide derivative designed for reduced toxicity and increased immunomodulatory properties. Lenalidomide has shown protective effects in an animal model of amyotrophic lateral sclerosis, and its mechanism of action involves modulation of cytokine production and inhibition of NF-κB signaling.

METHODS

In order to assess the effect of lenalidomide in an animal model of PD, mThy1-α-syn transgenic mice were treated with lenalidomide or the parent molecule thalidomide at 100 mg/kg for 4 weeks.

RESULTS

Lenalidomide reduced motor behavioral deficits and ameliorated dopaminergic fiber loss in the striatum. This protective action was accompanied by a reduction in microgliosis both in striatum and hippocampus. Central expression of pro-inflammatory cytokines was diminished in lenalidomide-treated transgenic animals, together with reduction in NF-κB activation.

CONCLUSION

These results support the therapeutic potential of lenalidomide for reducing maladaptive neuroinflammation in PD and related neuropathologies.

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.

Tumour necrosis factor-α inhibition with lenalidomide alleviates tissue oxidative injury and apoptosis in ob/ob obese mice

Lenalidomide (Revlimid; Selleck Chemicals, Houston, TX, USA), an analogue of thalidomide, possesses potent cytokine modulatory capacity through inhibition of cytokines such as tumour necrosis factor (TNF)-α, a cytokine pivotal for the onset and development of complications in obesity and diabetes mellitus. The present study was designed to evaluate the effect of lenalidomide on oxidative stress, protein and DNA damage in multiple organs in an ob/ob murine model of obesity. To this end, C57BL/6 lean and ob/ob obese mice were administered lenalidomide (50 mg/kg per day, p.o.) for 5 days. Oxidative stress, protein and DNA damage were assessed using the conversion of reduced glutathione (GSH) to oxidized glutathione (GSSG), carbonyl formation and Comet assay, respectively. Apoptosis was evaluated using caspase 3 activity, and levels of Bax, Bcl-2, Bip, caspase 8, caspase 9 and TNF-α were assessed using western blot analysis. Lenalidomide treatment did not affect glucose clearance in lean or ob/ob mice. Obese mice exhibited a reduced GSH/GSSG ratio in the liver, gastrocnemius skeletal muscle and small intestine, as well as enhanced protein carbonyl formation, DNA damage and caspase 3 activity in the liver, kidney, skeletal muscle and intestine; these effects were alleviated by lenalidomide, with the exception of obesity-associated DNA damage in the liver and kidney. Western blot analysis revealed elevated TNF-α, Bax, Bcl-2, Bip, caspase 8 and caspase 9 in ob/ob mice with various degrees of reversal by lenalidomide treatment. Together, these data indicate that lenalidomide protects against obesity-induced tissue injury and protein damage, possibly in association with antagonism of cytokine production and cytokine-induced apoptosis and oxidative stress.