Thalidomide-induced neuropathy

Withdrawn 2.0-update on withdrawn drugs with pharmacovigilance data

One challenge in the development of novel drugs is their interaction with potential off-targets, which can cause unintended side-effects, that can lead to the subsequent withdrawal of approved drugs. At the same time, these off-targets may also present a chance for the repositioning of withdrawn drugs for new indications, which are potentially rare or more severe than the original indication and where certain adverse reactions may be avoidable or tolerable. To enable further insights into this topic, we updated our database Withdrawn by adding pharmacovigilance data from the FDA Adverse Event Reporting System (FAERS), as well as mechanism of action and human disease pathway prediction features for drugs that are or were temporarily withdrawn or discontinued in at least one country. As withdrawal data are still spread over dozens of national websites, we are continuously updating our lists of discontinued or withdrawn drugs and related (off-)targets. Furthermore, new systematic entry points for browsing the data, such as an ATC tree, were added, increasing the accessibility of the database in a user-friendly way. Withdrawn 2.0 is publicly available without the need for registration or login at https://bioinformatics.charite.de/withdrawn_3/index.php.

Axonal degeneration in chemotherapy-induced peripheral neurotoxicity: clinical and experimental evidence

Multiple pathological mechanisms are involved in the development of chemotherapy-induced peripheral neurotoxicity (CIPN). Recent work has provided insights into the molecular mechanisms underlying chemotherapy-induced axonal degeneration. This review integrates evidence from preclinical and clinical work on the onset, progression and outcome of axonal degeneration in CIPN. We review likely triggers of axonal degeneration in CIPN and highlight evidence of molecular pathways involved in axonal degeneration and their relevance to CIPN, including SARM1-mediated axon degeneration pathway. We identify potential clinical markers of axonal dysfunction to provide early identification of toxicity as well as present potential treatment strategies to intervene in axonal degeneration pathways. A greater understanding of axonal degeneration processes in CIPN will provide important information regarding the development and progression of axonal dysfunction more broadly and will hopefully assist in the development of successful interventions for CIPN and other neurodegenerative disorders.

Update on Toxic Neuropathies

Purpose of Review

Toxic neuropathies are an important preventable and treatable form of peripheral neuropathy. While many forms of toxic neuropathies have been recognized for decades, an updated review is provided to increase vigilant in this area of neurology. A literature review was conducted to gather recent information about toxic neuropathies, which included the causes, clinical findings, and treatment options in these conditions.

Recent Findings

Toxic neuropathies continue to cause significant morbidity throughout the world and the causative agents, particularly with regards to medications, do not appear to be diminishing. A wide variety of causes of toxic neuropathies exist, which include alcohol, industrial chemicals, biotoxins, and medications. Unfortunately, no breakthrough treatments have been developed and prevention and symptom management remain the standard of care.

Summary

A detailed medication, occupational and hobby exposure history is critical to identifying toxic neuropathies. Increased research is warranted to identify mechanisms of neurotoxic susceptibility and potential common pathomechanistic pathways for treatment across diverse toxic neuropathies.

A chemogenomic approach is required for effective treatment of amyotrophic lateral sclerosis

ALS is a fatal untreatable disease involving degeneration of motor neurons. Μultiple causative genes encoding proteins with versatile functions have been identified indicating that diverse biological pathways lead to ALS. Chemical entities still represent a promising choice to delay ALS progression, attenuate symptoms and/or increase life expectancy, but also gene-based and stem cell-based therapies are in the process of development, and some are tested in clinical trials. Various compounds proved effective in transgenic models overexpressing distinct ALS causative genes unfortunately though, they showed no efficacy in clinical trials. Notably, while animal models provide a uniform genetic background for preclinical testing, ALS patients are not stratified, and the distinct genetic forms of ALS are treated as one group, which could explain the observed discrepancies between treating genetically homogeneous mice and quite heterogeneous patient cohorts. We suggest that chemical entity-genotype correlation should be exploited to guide patient stratification for pharmacotherapy, that is administered drugs should be selected based on the ALS genetic background.

Chemotherapy-Induced Peripheral Neuropathy: Epidemiology, Pathomechanisms and Treatment

PURPOSE

This review provides an update on the current clinical, epidemiological and pathophysiological evidence alongside the diagnostic, prevention and treatment approach to chemotherapy-induced peripheral neuropathy (CIPN).

FINDINGS

The incidence of cancer and long-term survival after treatment is increasing. CIPN affects sensory, motor and autonomic nerves and is one of the most common adverse events caused by chemotherapeutic agents, which in severe cases leads to dose reduction or treatment cessation, with increased mortality. The primary classes of chemotherapeutic agents associated with CIPN are platinum-based drugs, taxanes, vinca alkaloids, bortezomib and thalidomide. Platinum agents are the most neurotoxic, with oxaliplatin causing the highest prevalence of CIPN. CIPN can progress from acute to chronic, may deteriorate even after treatment cessation (a phenomenon known as coasting) or only partially attenuate. Different chemotherapeutic agents share both similarities and key differences in pathophysiology and clinical presentation. The diagnosis of CIPN relies heavily on identifying symptoms, with limited objective diagnostic approaches targeting the class of affected nerve fibres. Studies have consistently failed to identify at-risk cohorts, and there are no proven strategies or interventions to prevent or limit the development of CIPN. Furthermore, multiple treatments developed to relieve symptoms and to modify the underlying disease in CIPN have failed.

IMPLICATIONS

The increasing prevalence of CIPN demands an objective approach to identify at-risk patients in order to prevent or limit progression and effectively alleviate the symptoms associated with CIPN. An evidence base for novel targets and both pharmacological and non-pharmacological treatments is beginning to emerge and has been recognised recently in publications by the American Society of Clinical Oncology and analgesic trial design expert groups such as ACTTION.

Molecular Mechanisms of Cereblon-Interacting Small Molecules in Multiple Myeloma Therapy

Thalidomide analogues (or immunomodulatory imide drugs, IMiDs) are cornerstones in the treatment of multiple myeloma (MM). These drugs bind Cereblon (CRBN), a receptor for the Cullin-ring 4 ubiquitin-ligase (CRL4) complex, to modify its substrate specificity. IMiDs mediate CRBN-dependent engagement and proteasomal degradation of ‘neosubstrates’, Ikaros (IKZF1) and Aiolos (IKZF3), conveying concurrent antimyeloma activity and T-cell costimulation. There is now a greater understanding of physiological CRBN functions, including endogenous substrates and chaperone activity. CRISPR Cas9-based genome-wide screening has further elucidated the complex cellular machinery implicated in IMiD sensitivity, including IKZF1/3-independent mechanisms. New-generation IMiD derivatives with more potent anti-cancer properties—the CELMoDs (Cereblon E3 ligase modulators)—are now being evaluated. Rational drug design also allows ‘hijacking’ of CRL4^CRBN utilising proteolysis targeting chimeras (PROTACs) to convey entirely distinct substrate repertoires. As all these chemotypes—thalidomide, IMiDs, CELMoDs and PROTACs—engage CRBN and modify its functions, we describe them here in aggregate as ‘CRBN-interacting small molecules’ (CISMs). In this review, we provide a contemporary summary of the biological consequences of CRBN modulation by CISMs. Detailed molecular insight into CRBN–CISM interactions now provides an opportunity to more effectively target previously elusive cancer dependencies, representing a new and powerful tool for the implementation of precision medicine.

Supportive care in multiple myeloma: Current practices and advances

Supportive care in multiple myeloma (MM) can have a major impact on quality of life and the survival outcomes of MM patients. In this review, we will focus on disease and treatment related toxicities experienced by MM patients and what are the best approaches to date to help mitigate the effects. We will specifically focus on a practical approach to managing bone disease, thrombosis, infection risk, peripheral neuropathy, dermatologic complications, gastrointestinal and ocular toxicities, and fatigue in MM.

The use of thalidomide to treat children with tuberculosis meningitis: A review

Much of the morbidity and mortality caused by tuberculous meningitis (TBM) is mediated by a dysregulated immune response. Effective host-directed therapy is therefore critical to improve survival and clinical outcomes. Currently only one host-directed therapy (HDT), corticosteroids, is proven to improve mortality. However, there is no evidence that corticosteroids reduce morbidity and the mechanism of action for mortality reduction is uncertain. Further, it has no proven benefit in HIV co-infected individuals. One promising host-directed therapy approach is to restrict the immunopathology arising from tumour necrosis factor (TNF)-α excess is via TNF-α inhibitors. There are accumulating data on the role of thalidomide, anti-TNF-α monoclonal antibodies (infliximab, adalimumab) and the soluble TNF-α receptor (etanercept) in TBM treatment. Thalidomide was developed nearly seventy years ago and has been a highly controversial drug. Birth defects and toxic adverse effects have limited its use but an improved understanding of its immunological mechanism of action suggest that it may have a crucial role in regulating the destructive host response seen in inflammatory conditions such as TBM. Observational studies at our institution found low dosage adjunctive thalidomide safe in treating tuberculous mass lesions and blindness related to optochiasmatic arachnoiditis, with good clinical and radiological response. In this review, we discuss possible mechanisms of action for thalidomide, based on our clinico-radiologic experience and post-mortem histopathological work. We also propose a rationale for its use in the treatment of certain TBM-related complications.

Thalidomide and Lenalidomide for Refractory Systemic/Cutaneous Lupus Erythematosus Treatment: A Narrative Review of Literature for Clinical Practice

BACKGROUND

Thalidomide has shown exceptional results in systemic/cutaneous lupus erythematosus(SLE/CLE). Recently, lenalidomide has been also prescribed for SLE/CLE treatment. Literature regarding efficacy/adverse events for these drugs is scarce with a single systematic review and meta-analysis focused solely on thalidomide for refractory cutaneous lupus subtypes.

OBJECTIVE

We, therefore, addressed in this narrative review the efficacy/adverse effects of thalidomide and lenalidomide for SLE and CLE. In addition, we provide a specialist approach for clinical practice based on the available evidence.

RESULTS

Efficacy of thalidomide for refractory cutaneous lupus treatment was demonstrated by several studies, mostly retrospective with small sample size(≤20). The frequency of peripheral polyneuropathy is controversial varying from 15-80% with no consistent data regarding cumulative dose and length of use. Drug withdrawn results in clinical partial/complete reversibility for most cases (70%). For lenalidomide, seven studies (small sample sizes) reported its efficacy for SLE/CLE with complete/partial response in all patients with a mean time to response of 3 months. Flare rate varied from 25-75% occurring 0.5-10 months after drug withdrawn. There were no reports of polyneuropathy/worsening of previous thalidomide-induced neuropathy, but most of them did not perform nerve conduction studies. Teratogenicity risk exist for both drugs and strict precautions are required.

CONCLUSIONS

Thalidomide is very efficacious as an induction therapy for patients with severe/refractory cutaneous lupus with high risk of scarring, but its longstanding use should be avoided due to neurotoxicity. Lenalidomide is a promising drug for skin lupus treatment, particularly regarding the apparent lower frequency of nerve side effects.

Redox-sensitive TRP channels: a promising pharmacological target in chemotherapy-induced peripheral neuropathy

INTRODUCTION

Chemotherapy-induced peripheral neuropathy (CIPN) and its related pain is a major side effect of certain chemotherapeutic agents used in cancer treatment. Available analgesics are mostly symptomatic, and on prolonged treatment, patients become refractive to them. Hence, the development of improved therapeutics that act on novel therapeutic targets is necessary. Potential targets include the redox-sensitive TRP channels [e.g. TRPA1, TRPC5, TRPC6, TRPM2, TRPM8, TRPV1, TRPV2, and TRPV4] which are activated under oxidative stress associated with CIPN.

AREAS COVERED

We have examined numerous neuropathy-inducing cancer chemotherapeutics and their pathophysiological mechanisms. Oxidative stress and its downstream targets, the redox-sensitive TRP channels, together with their potential pharmacological modulators, are discussed. Finally, we reflect upon the barriers to getting new therapeutic approaches into the clinic. The literature search was conducted in PubMed upto and including April 2021.

EXPERT OPINION

Redox-sensitive TRP channels are a promising target in CIPN. Pharmacological modulators of these channels have reduced pain in preclinical models and in clinical studies. Clinical scrutiny suggests that TRPA1, TRPM8, and TRPV1 are the most promising targets because of their pain-relieving potential. In addition to the analgesic effect, TRPV1 agonist-Capsaicin possesses a disease-modifying effect in CIPN through its restorative property in damaged sensory nerves.

Management of Myeloma Manifestations and Complications: The Cornerstone of Supportive Care: Recommendation of the Canadian Myeloma Research Group (formerly Myeloma Canada Research Network) Consensus Guideline Consortium

Multiple myeloma (MM) is a hematological cancer associated with significant symptomatic burden. Bone disease, renal insufficiency, cytopenias, infection, and peripheral neuropathy, among other disease manifestations and complications, impair patients' quality of life. The Canadian Myeloma Research Group Consensus Guideline Consortium, formerly Myeloma Canada Research Network Consensus Guideline Consortium, proposes national consensus recommendations for the management of MM-related manifestations and complications. To address the needs of Canadian physicians and people living with MM across the country, this document focuses on the improvement and maintenance of patient care by clarifying best-practice approaches for the prevention, detection and management of disease manifestations and complications. The Canadian Myeloma Research Group Consensus Guideline Consortium will periodically review the recommendations herein and update as necessary.

Role of innate immunity in chemotherapy-induced peripheral neuropathy

It has become increasingly clear that the innate immune system plays an essential role in the generation of many types of neuropathic pain including that which accompanies cancer treatment. In this article we review current findings of the role of the innate immune system in contributing to cancer treatment pain at the distal endings of peripheral nerve, in the nerve trunk, in the dorsal root ganglion and in the spinal dorsal horn.

Death and Rebirth of the Thalidomide Molecule: A Case of Thalidomide-Induced Sensory Neuropathy

The thalidomide molecule is a remarkable molecule that exists in a racemic mixture of optical isomers. In the 1950s, due to its teratogenicity, the levorotatory isomer led to its dramatic downfall. However, the molecule with its panoramic mechanisms of action and its uncanny ability to intercalate within the geometry of deoxyribonucleic acid (DNA), led to its remarkable renaissance; thalidomide being United States Food and Drug Administration (FDA)-approved for at least 13 different indications ranging from multiple myeloma to leprosy to glioblastoma. Thalidomide-induced polyneuropathy is usually reversible and is the rate-limiting step in its long-term use. The development of a polyneuropathy is invariably associated with a cumulative dose exceeding 20 grams. However, the polyneuropathy is almost always a sensory neuropathy. Asymmetry, bona fide weakness such as difficulty standing on the heels, a poly-ganglioneuropathy pattern with widespread or patchy numbness and sensory ataxia should raise a red flag and an alternative diagnosis should be considered. We present a typical case of a thalidomide-induced sensory neuropathy in order to highlight the resurgence of thalidomide use in clinical practice. We review the literature and outline the molecular biology of the thalidomide molecule.

Mechanisms of Nerve Damage in Neuropathies Associated with Hematological Diseases: Lesson from Nerve Biopsies

Despite the introduction of non-invasive techniques in the study of peripheral neuropathies, sural nerve biopsy remains the gold standard for the diagnosis of several neuropathies, including vasculitic neuropathy and neurolymphomatosis. Besides its diagnostic role, sural nerve biopsy has helped to shed light on the pathogenic mechanisms of different neuropathies. In the present review, we discuss how pathological findings helped understand the mechanisms of polyneuropathies complicating hematological diseases.

Oxidative stress mediates thalidomide-induced pain by targeting peripheral TRPA1 and central TRPV4

Background

The mechanism underlying the pain symptoms associated with chemotherapeutic-induced peripheral neuropathy (CIPN) is poorly understood. Transient receptor potential ankyrin 1 (TRPA1), TRP vanilloid 4 (TRPV4), TRPV1, and oxidative stress have been implicated in several rodent models of CIPN-evoked allodynia. Thalidomide causes a painful CIPN in patients via an unknown mechanism. Surprisingly, the pathway responsible for such proalgesic response has not yet been investigated in animal models.

Results

Here, we reveal that a single systemic administration of thalidomide and its derivatives, lenalidomide and pomalidomide, elicits prolonged (~ 35 days) mechanical and cold hypersensitivity in C57BL/6J mouse hind paw. Pharmacological antagonism or genetic deletion studies indicated that both TRPA1 and TRPV4, but not TRPV1, contribute to mechanical allodynia, whereas cold hypersensitivity was entirely due to TRPA1. Thalidomide per se did not stimulate recombinant and constitutive TRPA1 and TRPV4 channels in vitro, which, however, were activated by the oxidative stress byproduct, hydrogen peroxide. Systemic treatment with an antioxidant attenuated mechanical and cold hypersensitivity, and the increase in oxidative stress in hind paw, sciatic nerve, and lumbar spinal cord produced by thalidomide. Notably, central (intrathecal) or peripheral (intraplantar) treatments with channel antagonists or an antioxidant revealed that oxidative stress-dependent activation of peripheral TRPA1 mediates cold allodynia and part of mechanical allodynia. However, oxidative stress-induced activation of central TRPV4 mediated the residual TRPA1-resistant component of mechanical allodynia.

Conclusions

Targeting of peripheral TRPA1 and central TRPV4 may be required to attenuate pain associated with CIPN elicited by thalidomide and related drugs.

Therapeutic effectiveness of thalidomide in a patient with treatment-resistant restless legs syndrome

None

Recent developments in the genetics of restless legs syndrome (RLS) revealed associations of disease risk with genetic loci containing the genes coding cereblon, the protein bound by thalidomide, and its endogenous substrate MEIS2, whose degradation is inhibited by the thalidomide-cereblon interaction. Therefore it was hypothesized that thalidomide may be a potential treatment option for RLS. Here we report on the therapeutic effect of thalidomide in a patient with otherwise treatment-resistant RLS who received 100 mg thalidomide off-label for 3 weeks. The female patient, severely affected by RLS before treatment, experienced significant amelioration of the symptoms, increased self-reported sleep quality, and better daytime functioning during thalidomide treatment. This therapeutic success warrants larger studies investigating the efficacy of drugs of the thalidomide class in RLS.

Use of methotrexate for leprosy reactions. Experience of a referral center and systematic review of the literature

BACKGROUND

Patients with leprosy can present with systemic inflammatory complications called leprosy reactions (LR), which can be severe and cause a loss of nerve function. The treatment of choice is prolonged corticosteroid therapy, frequently associated with severe side effects. We have used methotrexate as a corticosteroid-sparing regimen with good results.

METHODS

To evaluate the role of methotrexate in managing LR, we performed a systematic review of the literature including our cases. We evaluated studies, prospective and retrospective, in both adults and children, which included any dose/regimen of methotrexate for the treatment of LR type 1 or 2.

RESULTS

The systematic search revealed 261 records that yield 21 patients including our 3 cases (19 adults/two children), who were treated with methotrexate for LR type 1 and 2. There were 14 males. Median age was 35 years (P₂₅-P₇₅ 28 to 52). Patients showed lepromatous (7), borderline lepromatous (9) or borderline tuberculoid (3) leprosy, among the 19 cases in which the type of leprosy was specified. As for the type of LR, 15 patients showed erythema nodosum leprosum (ENL), five showed LR type 1 and one showed polyarthritis and previous ENL. Methotrexate at weekly doses ranging from 7.5 mg to 20 mg (median 15 mg per week), typically administered with low-dose corticosteroids, was effective and safe as a corticosteroid-sparing agent.

CONCLUSIONS

Methotrexate could be a suitable ancillary treatment or alternative to corticosteroids, especially in populations who are more prone to its adverse events. However, this evidence is based only on case reports and short clinical series.

Vinca alkaloids, thalidomide and eribulin-induced peripheral neurotoxicity: From pathogenesis to treatment

Vinca alkaloids, thalidomide, and eribulin are widely used to treat patients with childhood acute lymphoblastic leukemia (ALL), adults affected by multiple myeloma and locally invasive or metastatic breast cancer, respectively. However, soon after their introduction into clinical practice, chemotherapy-induced peripheral neurotoxicity (CIPN) emerged as their main non-hematological and among dose-limiting adverse events. It is generally perceived that vinca alkaloids and the antiangiogenic agent thalidomide are more neurotoxic, compared to eribulin. The exposure to these chemotherapeutic agents is associated with an axonal, length-dependent, sensory polyneuropathy of mild to moderate severity, whereas it is considered that the peripheral nerve damage, unless severe, usually resolves soon after treatment discontinuation. Advanced age, high initial and prolonged dosing, coadministration of other neurotoxic chemotherapeutic agents and pre-existing neuropathy are the common risk factors. Pharmacogenetic biomarkers might be used to define patients at increased susceptibility of CIPN. Currently, there is no established therapy for CIPN prevention or treatment; symptomatic treatment for neuropathic pain and dose reduction or withdrawal in severe cases is considered, at the cost of reduced cancer therapeutic efficacy. This review critically examines the pathogenesis, epidemiology, risk factors (both clinical and pharmacogenetic), clinical phenotype and management of CIPN as a result of exposure to vinca alkaloids, thalidomide and its analogue lenalidomide as also eribulin.

Late-onset ulnar neuritis following treatment of lepromatous leprosy infection

Neuritis is a frequent complication of Myocobacteria leprae infection and treatment due to the variety of mechanisms through which it can occur. Not only can mycobacterial invasion into peripheral nerves directly cause damage and inflammation, but immune-mediated inflammatory episodes (termed leprosy reactions) can also manifest as neuritis at any point during infection. Treatment of leprosy reactions with thalidomide can also lead to neuritis due to an adverse drug effect. Neuritis can emerge years after initial diagnosis and treatment, although it is most frequently found at time of diagnosis or early into the treatment course. Treatment of neuritis is dependent on high-dose corticosteroid therapy as well as therapy for suspected underlying etiology. Here, we present a case of ulnar neuritis presenting in a patient with lepromatous leprosy four years after treatment of initial infection, with subsequent improvement after corticosteroid burst while maintained on thalidomide therapy.

Leprosy infection is frequently complicated by peripheral neuritis, but is often difficult to distinguish if it is due to persistent infection, an immune-mediated reaction, or adverse drug reaction. In this case, we present a patient with ulnar neuritis occurring four years after multidrug therapy, with improvement with high-dose corticosteroid therapy while remaining on thalidomide treatment.

Phthalimide Derivative Shows Anti-angiogenic Activity in a 3D Microfluidic Model and No Teratogenicity in Zebrafish Embryos

Angiogenesis is a crucial event for tumor progression and metastasis. It is the process through which new blood vessels are formed and has become a therapeutic target in many cancer therapies. However, current anti-angiogenic drugs such as Thalidomide still have detrimental teratogenic effects. This property could be caused by the presence of chiral carbons, intrinsic to such compounds. We synthesized four different phthalimide derivatives that lack chiral carbons in their chemical structure. We hypothesized that these achiral carbon compounds would retain similar levels of anti-angiogenic activity whilst reducing teratogenic effects. We tested for their anti-angiogenic functions using an in vitro 3D microfluidic assay with human endothelial cells. All four compounds caused a drastic inhibition of angiogenesis at lower effective concentrations compared to Thalidomide. Quantification of the blood vessel sprouting in each condition allowed us to classify compounds depending on their anti-angiogenic capabilities. The most effective identified compound (C4), was tested in vivo on a zebrafish embryo model. Blood vessel development was measured using number and lengths of the stalks visible in the fli1a:EGFP transgenic line. Potential teratogenic effects of C4 were monitored over zebrafish embryonic development. The in vivo results confirmed the increased potency of C4 compared to Thalidomide demonstrated by results in embryos exposed to concentrations as low as 0.02 μM. The teratogenic analysis further validated the advantages of using C4 over Thalidomide in zebrafish embryos. This study highlights how the use of in vitro 3D model can allow rapid screening and selection of new and safer drugs.

Medicinal plants and their isolated phytochemicals for the management of chemotherapy-induced neuropathy: therapeutic targets and clinical perspective

BACKGROUND

Chemotherapy, as one of the main approaches of cancer treatment, is accompanied with several adverse effects, including chemotherapy-induced peripheral neuropathy (CIPN). Since current methods to control the condition are not completely effective, new treatment options should be introduced. Medicinal plants can be suitable candidates to be assessed regarding their effects in CIPN. Current paper reviews the available preclinical and clinical studies on the efficacy of herbal medicines in CIPN.

METHODS

Electronic databases including PubMed, Scopus, and Cochrane library were searched with the keywords "neuropathy" in the title/abstract and "plant", "extract", or "herb" in the whole text. Data were collected from inception until April 2018.

RESULTS

Plants such as chamomile (Matricaria chamomilla L.), sage (Salvia officinalis L.), cinnamon (Cinnamomum cassia (L.) D. Don), and sweet flag (Acorus calamus L.) as well as phytochemicals like matrine, curcumin, and thioctic acid have demonstrated beneficial effects in animal models of CIPN via prevention of axonal degeneration, decrease in total calcium level, improvement of endogenous antioxidant defense mechanisms such as superoxide dismutase and reduced glutathione, and regulation of neural cell apoptosis, nuclear factor-ĸB, cyclooxygenase-2, and nitric oxide signaling. Also, five clinical trials have evaluated the effect of herbal products in patients with CIPN.

CONCLUSIONS

There are currently limited clinical evidence on medicinal plants for CIPN which shows the necessity of future mechanistic studies, as well as well-designed clinical trial for further confirmation of the safety and efficacy of herbal medicines in CIPN. Graphical abstract Schematic mechanisms of medicinal plants to prevent chemotherapy-induced neuropathy: NO: nitric oxide, TNF: tumor necrosis factor, PG: prostaglandin, NF-ĸB: nuclear factor kappa B, LPO: lipid peroxidation, ROS: reactive oxygen species, COX: cyclooxygenase, IL: interleukin, ERK: extracellular signal-related kinase, X: inhibition, ↓: induction.

Extrapyramidal Symptoms with Administration of Lenalidomide Maintenance Therapy for Multiple Myeloma

Lenalidomide is commonly used as induction or maintenance therapy in multiple myeloma. We report a case of 71-year-old female presenting with tardive dyskinesia-like symptoms one month after starting her lenalidomide maintenance therapy after high-dose chemotherapy and autologous hematopoietic stem cell rescue. Her symptoms evolved over days to pronounced uncontrollable limb movements, tongue smacking, lip-smacking, abnormal sounds, and tongue biting. The patient categorically denied any exposure to other drugs which are known to cause symptoms of tardive dyskinesia. The patient underwent a thorough evaluation, stopped the lenalidomide, and received therapy to control her symptoms with a gradual improvement over a six-week period. There is a paucity of literature on the association of lenalidomide with tardive dyskinesia. Common central nervous system-related side effects include peripheral neuropathy, dizziness, dysgeusia, headache, tremor, somnolence, and memory impairment. Very few studies in the existing literature have reported an association of tardive dyskinesia with lenalidomide therapy. Here, we present a case of an elderly female with multiple myeloma who developed severe tardive dyskinesia while she was on lenalidomide maintenance therapy.

In Search of a Gold Standard Patient-Reported Outcome Measure for Use in Chemotherapy- Induced Peripheral Neuropathy Clinical Trials

Purpose:

To test a reduced version—CIPN15—of the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Chemotherapy-Induced Peripheral Neuropathy scale (QLQ-CIPN20) to establish a possible gold-standard patient-reported outcome measure for chemotherapy-induced peripheral neuropathy (CIPN).

Methods:

Using a prospective, longitudinal, case–control design, patients (n = 121) receiving neurotoxic chemotherapy completed the CIPN15 at baseline and 12 weeks and underwent objective neurological assessment using the 5-item Total Neuropathy Score-Clinical (TNSc). Healthy controls (n = 30) completed the CIPN15 once. Structural validity was evaluated using factor analysis. Because a stable factor structure was not found, a sum score was used to evaluate measures of the CIPN15’s psychometric properties—reliability, validity, sensitivity, and responsiveness—as follows: internal consistency via Cronbach’s α and item–item correlations; test–retest reliability via correlation between 2 CIPN15 scores from each patient; concurrent validity via correlation between CIPN15 and 5-item TNSc scores; contrasting group validity via comparison of CIPN15 scores from patients and healthy controls; sensitivity via descriptive statistics (means, standard deviation, ranges); and responsiveness via Cohen’s d effect size.

Results:

Most patients received single agent oxaliplatin (33.7%), paclitaxel (21.2%), or more than 1 neurotoxic drug concurrently (29.8%). Factor analysis revealed no stable factor structure. Cronbach’s α for the CIPN15 sum score was 0.91 (confidence interval [CI] = 0.89-0.93). Test–retest reliability was demonstrated based on strong correlations between the 2 scores obtained at the 12-week time point (r = 0.86; CI = 0.80-0.90). The CIPN15 and 5-item TNSc items reflecting symptoms (not signs) were moderately correlated (r range 0.57-0.72): concurrent validity. Statistically significant differences were found between patient and healthy control CIPN15 mean scores (P < .0001): contrasting group validity. All items encompassed the full score range but the CIPN15 linearly converted sum score did not: sensitivity. The CIPN15 was responsive based on a Cohen’s d of 0.52 (CI = 0.25-0.79).

Conclusion:

The sum-scored CIPN15 is reliable, valid, sensitive, and responsive when used to assess taxane- and platinum-induced CIPN.

Pitfalls of Combining Novel Agents in Lymphoma

OPINION STATEMENT

As our knowledge of lymphoma and its intricate signaling pathways has grown, so has the development of novel agents. While their mechanisms of action vary considerably, these therapies supplement and in some cases offer alternatives to standard chemotherapy. Initial studies have highlighted tolerable side effects though in the majority of instances limited efficacy when used as monotherapy. Research has focused on combining these novel agents to improve outcomes and perhaps offer refined treatment options. Novel combinations represent new territory, inherently dissimilar to combination chemotherapy with new pitfalls and challenges given their unique mechanisms of action. Though promising, it is crucial to consider the complex interplay that can occur. While there is potential for improved outcomes, there is also the possibility of unexpected toxicities. For this reason, it is critical that novel combinations be carefully considered and tested in clinical trials before widespread use. Thus far, research has shown that combination therapies are successful when not only avoiding overlapping toxicity but also capitalizing on synergy. We believe that more specific targets and an improved understanding of their off-/on-target effects will further successful novel combinations.

Risk Factors and Outcomes of Thalidomide-induced Peripheral Neuropathy in a Pediatric Inflammatory Bowel Disease Cohort

BACKGROUND

Thalidomide is an effective therapy in children with inflammatory bowel disease refractory to standard treatments, but thalidomide-induced peripheral neuropathy (TiPN) limits its long-term use. We aimed to investigate the risk factors and the outcome of TiPN in children with inflammatory bowel disease.

METHODS

Within a retrospective multicenter cohort study, we evaluated prevalence and evolution of TiPN. Clinical data and candidate genetic profiles of patients with and without TiPN were compared with detect predisposing factors.

RESULTS

One hundred forty-two patients were identified. TiPN was found in 72.5% of patients (38.7% clinical and instrumental alterations, 26.8% exclusive electrophysiological anomalies, and 7.0% exclusive neurological symptoms). Median TiPN-free period of treatment was 16.5 months; percentage of TiPN-free patients was 70.0% and 35.6% at 12 and 24 months of treatment, respectively. The risk of TiPN increased depending on the mean daily dose (50-99 mg/d adjusted hazard ratio 2.62; 95% confidence interval [CI], 1.31-5.21; 100-149 mg/d adjusted hazard ratio 6.16; 95% CI, 20.9-13.06; >150 mg/d adjusted hazard ratio 9.57; 95% CI, 2.6-35.2). Single nucleotide polymorphisms in ICAM1 (rs1799969) and SERPINB2 (rs6103) genes were found to be protective against TiPN (odds ratio 0.15; 95% CI, 0.03-0.82 and 0.36; 95% CI, 0.14-0.88, respectively). TiPN was the cause of drug suspension in 41.8% of patients. Clinical symptoms resolved in 89.2% of cases, whereas instrumental alteration persisted in more than half of the patients during a short follow-up.

CONCLUSIONS

In children with inflammatory bowel disease, TiPN is common but mild and generally reversible. Cumulative dose seems to be the most relevant risk factor, whereas polymorphisms in genes involved in neuronal inflammation may be protective.

Neurophysiological and clinical outcomes in chemotherapy-induced neuropathy in cancer

Chemotherapy induced peripheral neuropathy (CIPN) is a significant toxicity of cancer treatment, with the potential to affect long-term function and quality of life in cancer survivors. There remains a lack of consensus around optimal assessment techniques. While current approaches to CIPN assessment are focused on clinical grading scales, it is becoming increasingly evident that a more comprehensive multimodal assessment package is necessary to accurately characterise the impact of CIPN as well as gauge the utility of neuroprotective mechanisms. Neurophysiological techniques provide objective biomarkers and may enable early detection of toxicity while patient reported outcomes are necessary to determine the significance of symptoms to individual patients. In addition to providing an objective assessment, clinical neurophysiological techniques provide important insights into the contributory pathophysiological mechanisms of CIPN with different chemotherapy agents. There is a paucity of implementation of these techniques in the clinical trial setting. The present Review aims to facilitate the use of neurophysiological studies as part of comprehensive assessment packages for the monitoring of CIPN by summarising current understanding of neurophysiological changes that underlie the development of neuropathy, clinical presentations and patient reported outcomes as well as advantages and limitations of current techniques for the neurophysiological assessment of CIPN.

Longitudinal Patterns of Thalidomide Neuropathy in Children and Adolescents

OBJECTIVE

To characterize the longitudinal clinical and electrophysiological patterns of thalidomide neuropathy in children and adolescents.

STUDY DESIGN

Retrospective analysis of clinical records at a tertiary care children's hospital, including serial electrophysiological studies.

RESULTS

Sixteen patients aged 6-24 years received thalidomide to treat Crohn's disease from 2002 to 2012. Nine subjects had electrophysiological evidence of sensorimotor axonal polyneuropathy, 8 of whom had sensory and/or motor symptoms. The patients with polyneuropathy received thalidomide for 5 weeks to 52 months, with cumulative doses ranging from 1.4 to 207.7 g. All subjects with cumulative doses greater than 60 g developed polyneuropathy, and 4 of the 5 subjects who received thalidomide for more than 20 months developed polyneuropathy. The 7 subjects who had normal neurophysiological studies received therapy for 1 week to 25 months, with cumulative doses ranging from 0.7 to 47 g. In contrast to some previous reports, several patients had sensorimotor polyneuropathies, rather than pure sensory neuropathies. In patients with neuropathy who received therapy for more than 24 months and had 3 or more electromyography studies, the severity of the neuropathy plateaued.

CONCLUSIONS

Factors in addition to the total dose may contribute to the risk profile for thalidomide neuropathy, including pharmacogenetic susceptibilities. The severity of the neuropathy does not worsen relentlessly. Children, adolescents, and young adults receiving thalidomide should undergo regular neurophysiological studies to monitor for neuropathy.

Thalidomide for inflammatory bowel disease: Systematic review

BACKGROUND

Thalidomide is an immunomodulatory drug used in the experimental treatment of refractory Crohn disease and ulcerative colitis. We aimed to review the existing evidence on the efficacy and safety of thalidomide in the treatment of inflammatory bowel diseases.

METHODS

CENTRAL, MEDLINE, LILACS, POPLINE, CINHAL, and Web of Science were searched in March 2016. Manual search included conference and reference lists. All types of studies, except single case reports, were included. Outcomes evaluated were: induction of remission; maintenance of remission; steroid reduction; effect on penetrating Crohn disease; endoscopic remission; adverse events.

RESULTS

The research strategies retrieved 722 papers. Two randomized controlled trials and 29 uncontrolled studies for a total of 489 patients matched the inclusion criteria. Thalidomide induced a clinical response in 296/427 (69.3%) patients. Clinical remission was achieved in 220/427 (51.5%) cases. Maintenance of remission was reported in 128/160 (80.0%) patients at 6 months and in 96/133 (72.2%) at 12 months. Reduction in steroid dosage was reported in 109/152 (71.7%) patients. Fistulas improved in 49/81 (60.5%) cases and closed in 28/81 (34.6%). Endoscopic improvement was observed in 46/66 (69.7%) and complete mucosal healing in 35/66 (53.0%) patients. Cumulative incidence of total adverse events and of those leading to drug suspension was 75.6 and 19.7/1000 patient-months, respectively. Neurological disturbances accounted for 341/530 (64.3%) adverse events and were the most frequent cause of drug withdrawal.

CONCLUSION

Existing evidence suggests that thalidomide may be a valid treatment option for patients with inflammatory bowel diseases refractory to other first- and second-line treatments.

Assessment scales for the diagnosis of polyneuropathy

Epidemiological studies that investigate the occurrence and determinants of chronic length-dependent polyneuropathy are scarce. Population-based studies on polyneuropathy require a valid and reliable screening protocol with both good sensitivity and specificity. Several questionnaires and scoring scales have been developed for the detection of polyneuropathy, grading the severity of the disease, or evaluating the clinical course during follow-up. This review summarizes the aims and content of existing diagnostic polyneuropathy screening tools in order to help future studies decide which scale to use for screening in specific situations. We searched the PubMed database and identified 27 scales, 13 are based on symptoms alone, 8 on neurological signs alone, and 6 on a combination of symptoms and signs. Scales that combine questions concerning symptoms and a neurological examination with a focus on sensory alterations seem to have the best discriminatory power. However, all scoring scales were developed for and investigated in prespecified patient populations. Therefore, the generalizability of specific findings to the general population may be limited. We also discuss other limitations of existing scales. Future studies are required to determine which clinimetrically well-developed scales are preferred for use in population-based studies.

Axonal Transport Impairment in Chemotherapy-Induced Peripheral Neuropathy

Chemotherapy-Induced Peripheral Neuropathy (CIPN) is a dose-limiting side effect of several antineoplastic drugs which significantly reduces patients’ quality of life. Although different molecular mechanisms have been investigated, CIPN pathobiology has not been clarified yet. It has largely been recognized that Dorsal Root Ganglia are the main targets of chemotherapy and that the longest nerves are the most damaged, together with fast axonal transport. Indeed, this bidirectional cargo-specific transport has a pivotal role in neuronal function and its impairment is involved in several neurodegenerative and neurodevelopmental diseases. Literature data demonstrate that, despite different mechanisms of action, all antineoplastic agents impair the axonal trafficking to some extent and the severity of the neuropathy correlates with the degree of damage on this bidirectional transport. In this paper, we will examine the effect of the main old and new chemotherapeutic drug categories on axonal transport, with the aim of clarifying their potential mechanisms of action, and, if possible, of identifying neuroprotective strategies, based on the knowledge of the alterations induced by each drugs.

The clinical implications of thalidomide in inflammatory bowel diseases

Thalidomide has anti-inflammatory and anti-angiogenetic activity that makes it suitable for treating inflammatory bowel diseases (IBD). The recent guidelines from the European Crohn's and Colitis Organization/European Society for Pediatric Gastroenterology Hepatology and Nutrition conclude that thalidomide cannot be recommended in refractory pediatric Crohn's disease but that it may be considered in selected cohorts of patients who are not anti-TNFα agent responders. The main adverse effect is the potential teratogenicity that renders the long-term use of thalidomide problematic in young adults due to the strict need for contraceptive use. In short-term use it is relatively safe; the most likely adverse effect is the neuropathy, which is highly reversible in children. So far the use of thalidomide is reported in 223 adult and pediatric IBD patients (206 with Crohn's disease). In the following sections, the authors will discuss efficacy and safety of thalidomide, in the short-term treatment of IBD.

Therapy-related peripheral neuropathy in multiple myeloma patients

This review discusses the most common issues concerning multiple myeloma (MM)-related peripheral neuropathy (PN). This is an important MM complication, observed in up to 54% of newly diagnosed patients, caused by the disease itself or its treatment. Although its aetiology is largely unknown, a number of mechanisms are suspected. It is important to know the neurological status of a patient, as many new antimyeloma medicines can trigger or exacerbate any pre-existing neuropathy. Examples include thalidomide-induced and bortezomib-induced PN (TiPN and BiTN, respectively), which are key MM treatment options. TiPN is usually sensory and sensorimotor, whereas BiPN is typically sensory. The mechanisms of chemotherapy-induced neurotoxicity in MM are well known; thalidomide seems to induce PN through its antiangiogenic properties, whereas bortezomib neurotoxicity is connected with disrupted calcium homeostasis. TiPN incidence ranges from 25% to 75%, and its prevalence and severity appears to be dose-dependent. BiPN incidence is almost 40% and is dose-related as well. Poor (25%) reversibility of TiPN prompted the recommendations for dose and exposure reduction, whereas BiPN cases are mostly reversible (64%). Peripheral sensory neuropathy is very rare in patients receiving bendamustine monotherapy. Because of this favourable toxicity profile, bendamustine may be considered a promising option for combination therapies in pre-existing PN in myeloma patients. Considering the lack of curative therapy for treatment-emergent PN, prevention is a key management strategy in MM patients. All patients should be evaluated for PN before the administration of a neurotoxic drug, and those under treatment should be closely monitored by a neurologist.

Chemotherapy-induced peripheral neuropathy: What do we know about mechanisms?

Cisplatin, oxaliplatin, paclitaxel, vincristine and bortezomib are some of the most effective drugs successfully employed (alone or in combinations) as first-line treatment for common cancers. However they often caused severe peripheral neurotoxicity and neuropathic pain. Structural deficits in Dorsal Root Ganglia and sensory nerves caused symptoms as sensory loss, paresthesia, dysaesthesia and numbness that result in patient' suffering and also limit the life-saving therapy. Several scientists have explored the various mechanisms involved in the onset of chemotherapy-related peripheral neurotoxicity identifying molecular targets useful for the development of selected neuroprotective strategies. Dorsal Root Ganglia sensory neurons, satellite cells, Schwann cells, as well as neuronal and glial cells in the spinal cord, are the preferential sites in which chemotherapy neurotoxicity occurs. DNA damage, alterations in cellular system repairs, mitochondria changes, increased intracellular reactive oxygen species, alterations in ion channels, glutamate signalling, MAP-kinases and nociceptors ectopic activation are among the events that trigger the onset of peripheral neurotoxicity and neuropathic pain. In the present work we review the role of the main players in determining the pathogenesis of anticancer drugs-induced peripheral neuropathy.

Chemotherapy-induced peripheral neuropathies in hematological malignancies

Recent developments in the treatment of hematological malignancies, especially with the advent of proteasome inhibitors and immunomodulatory drugs in plasma cell dyscrasias, call for an increased collaboration between hematologists and neurologists. This collaboration involves differentiating chemotherapy-induced peripheral neuropathies (CiPN) from disease-related neurologic complications, early recognition of CiPN and treatment of neuropathic pain. Multiple myeloma, Waldenstrom's macroglobulinemia and light-chain amyloidosis frequently present with peripheral neuropathy. In addition, multiple myeloma, non-Hodgkin lymphomas and leukemia's may mimic peripheral neuropathy by compression or invasion of the extra/intradural space. Platinum compounds, vinca alkaloids, proteasome inhibitors and immunomodulatory drugs may all cause CiPN, each with different and often specific clinical characteristics. Early recognition, by identifying the distinct clinical phenotype of CiPN, is of crucial importance to prevent irreversible neurological damage. No recommendations can be given on the use of neuroprotective strategies because of a lack of convincing clinical evidence. Finally, CiPN caused by vinca-alkaloids, proteasome inhibitors and immunomodulatory drugs is often painful and neurologists are best equipped to treat this kind of painful neuropathy.

Measuring vincristine-induced peripheral neuropathy in children with acute lymphoblastic leukemia

BACKGROUND

Vincristine-induced peripheral neuropathy (VIPN) is difficult to quantify in children.

OBJECTIVE

The study objective was to examine the reliability, validity, and clinical feasibility of several VIPN measures for use in children with acute lymphoblastic leukemia.

INTERVENTIONS/METHODS

Children (n = 65) aged 1 to 18 years receiving vincristine at 4 academic centers participated in the study. Baseline and pre-vincristine administration VIPN assessments were obtained using the Total Neuropathy Score-Pediatric Vincristine (TNS©-PV), the National Cancer Institute Common Terminology Criteria for Adverse Events, the Balis grading scale, and the FACES Pain Scale. The TNS-PV scores (n = 806) were obtained over 15 weeks. Blood was obtained at several time points to quantify pharmacokinetic parameters.

RESULTS

Cronbach's α for a reduced TNS-PV scale was .84. The TNS-PV scores correlated with cumulative vincristine dosage (r = 0.53, P = 0.01), pharmacokinetic parameters (r = 0.41, P = 0.05), and grading scale scores (r range = 0.46-0.52, P = .01). FACES scores correlated with the TNS-PV neuropathic pain item (r = 0.48; P = .01) and were attainable in all ages. A 2-item V-Rex score (vibration and reflex items) was the most responsive to change (effect size = 0.65, P < 0.001). The TNS-PV scores were attainable in 95% of children 6 years or older.

CONCLUSIONS

The TNS-PV is reliable and valid for measuring VIPN. It is sensitive to change over time (15 weeks) and feasible for use in children 6 years or older.

IMPLICATIONS FOR PRACTICE

The TNS-PV may be a useful tool for assessing vincristine toxicity in children with acute lymphoblastic leukemia.

Lenalidomide in relapsed or refractory mantle cell lymphoma: overview and perspective

Lenalidomide, a novel immunomodulatory agent, was approved by the US Food and Drug Administration for the treatment of myelodysplastic syndrome and relapsed multiple myeloma. Data from preclinical studies paved the way for clinical trials of lenalidomide in mantle cell lymphoma (MCL). Initial phase I and II clinical trials of lenalidomide alone and as part of combination regimens in patients with relapsed/refractory MCL have shown promising results. Its immunomodulatory, T cell costimulatory, anti-inflammatory and anti-angiogenic actions working together in the tumor cell microenvironment seem to be responsible for its enhanced antitumor efficacy. Lenalidomide's nature of action and safety profile favor it over other agents studied in relapsed/refractory MCL. This review summarizes the data from preclinical and clinical studies of lenalidomide in relapsed/refractory MCL and compares the results with those of other novel agents being used for relapsed/refractory MCL.

Chemotherapy-induced peripheral neurotoxicity: a critical analysis

With a 3-fold increase in the number of cancer survivors noted since the 1970s, there are now over 28 million cancer survivors worldwide. Accordingly, there is a heightened awareness of long-term toxicities and the impact on quality of life following treatment in cancer survivors. This review will address the increasing importance and challenge of chemotherapy-induced neurotoxicity, with a focus on neuropathy associated with the treatment of breast cancer, colorectal cancer, testicular cancer, and hematological cancers. An overview of the diagnosis, symptomatology, and pathophysiology of chemotherapy-induced peripheral neuropathy will be provided, with a critical analysis of assessment strategies, neuroprotective approaches, and potential treatments. The review will concentrate on neuropathy associated with taxanes, platinum compounds, vinca alkaloids, thalidomide, and bortezomib, providing clinical information specific to these chemotherapies.

Lenalidomide in patients with chemotherapy-induced polyneuropathy and relapsed or refractory multiple myeloma: results from a single-centre prospective study

Lenalidomide, an immunomodulatory drug used in myeloma therapy, has been claimed to be less neurotoxic than thalidomide, but evidence is still weak. We prospectively assessed lenalidomide safety in myeloma patients to evaluate whether it would induce or modify a previously ensued chemotherapy-induced peripheral neuropathy (CIPN). Thirty consecutive patients (17 men, mean age 63.7 ± 9.4) previously treated with bortezomib and/or thalidomide and starting on lenalidomide (25 mg/day for 21-day cycles) for relapsed or refractory myeloma were assessed at baseline, 6, and 12 months from the beginning of lenalidomide with Total Neuropathy Score clinical version (TNSc), Eastern Cooperative Oncology Group (ECOG) performance status, and numeric rating scale (NRS) for pain. TNSc >2 was considered significant for CIPN. TNSc changes of at least 4 points from baseline value were considered clinically relevant. At baseline 16 of the 30 patients (53.3%) had CIPN (mean TNSc 5.8, range 3-15). After 6 months, 13 patients were unchanged, 1 improved, and 2 worsened. After 12 months the patient who had improved persisted stable, and the two who had worsened returned to TNSc baseline value. The 14 patients without CIPN at baseline did not develop neuropathy. NRS and ECOG performance status persisted unchanged. Our results demonstrate lenalidomide safety and very low neurotoxicity also in patients with pre-existing CIPN treated for 1 year.

Therapeutic effects of thalidomide in hematologic disorders: a review

The extensive autoimmune, anti-inflammatory, and anticancer applications of thalidomide have inspired a growing number of studies and clinical trials. As an inexpensive agent with relatively low toxicity, thalidomide is regarded as a promising therapeutic candidate, especially for malignant diseases. We review its therapeutic effects in hematology, including those on multiple myeloma, Waldenstroem macroglobulinemia, lymphoma, mantle-cell lymphoma, myelodysplastic syndrome, hereditary hemorrhagic telangiectasia, and graftversus-host disease. Most studies have shown satisfactory results, although several have reported the opposite. Aside from optimal outcomes, the toxicities and adverse effects of thalidomide should also be examined. The current work includes a discussion of the mechanisms through which the novel biological effects of thalidomide occur, although more studies should be devoted to this aspect. With appropriate safeguards, thalidomide may benefit patients suffering from a broad variety of disorders, particularly refractory and resistant diseases.