The clinical safety of lenalidomide in multiple myeloma and myelodysplastic syndromes

Minocycline for symptom reduction in patients with multiple myeloma during maintenance therapy: a phase II placebo-controlled randomized trial

BACKGROUND

Patients with multiple myeloma (MM) experience substantial cancer/treatment-related symptom burden during maintenance therapy. This is a phase II randomized, double-blinded, placebo-controlled clinical trial to examine the effect of minocycline for symptom reduction by its potential anti-inflammatory effect.

METHODS

Eligible MM patients for maintenance therapy were randomized to receive minocycline (100 mg twice daily) or placebo. The MD Anderson Symptom Inventory for MM (MDASI-MM) was used to assess multiple symptoms weekly during the trial. Clinician-rated toxicities and blood samples were prospectively collected. The effect size, area under the curve (AUC), and t tests were used to determine the symptom burden between treatment groups and identify the 5 most-severe MDASI-MM symptoms. The longitudinal analysis compared the changes in symptom severity and associated inflammatory markers between groups over time.

RESULTS

Sixty-nine evaluable MM patients (33 from the intervention group and 36 from the placebo group) were included. No grade 3+ adverse events related to study medication were noted. The AUCs for the 5 worst MDASI-MM symptoms (fatigue, pain, disturbed sleep numbness/tingling, and drowsiness) were not significantly different between two arms. Regardless of group assignment, pain reduction was positively associated with decreased serum levels of soluble tumor necrosis factor-α receptors 1 and 2 during therapy (all P < 0.05).

CONCLUSIONS

This pPhase II randomized study observed no statistically significant positive signal impact from minocycline on symptom reduction or inflammatory markers during maintenance therapy for MM, although using minocycline was feasible and had a low toxicity profile.

The application of ubiquitin ligases in the PROTAC drug design

Protein ubiquitylation plays important roles in many biological activities. Protein ubiquitylation is a unique process that is mainly controlled by ubiquitin ligases. The ubiquitin-proteasome system (UPS) is the main process to degrade short-lived and unwanted proteins in eukaryotes. Many components in the UPS are attractive drug targets. Recent studies indicated that ubiquitin ligases can be employed as tools in proteolysis-targeting chimeras (PROTACs) for drug discovery. In this review article, we will discuss the recent progress of the application of ubiquitin ligases in the PROTAC drug design. We will also discuss advantages and existing problems of PROTACs. Moreover, we will propose a few principles for selecting ubiquitin ligases in PROTAC applications.

The clinical management of lenalidomide-based therapy in patients with newly diagnosed multiple myeloma

Lenalidomide is an integral, yet evolving, part of current treatment pathways for both transplant-eligible and transplant-ineligible patients with newly diagnosed multiple myeloma (NDMM). It is approved in combination with dexamethasone as first-line therapy for transplant-ineligible patients with NDMM, and as maintenance treatment following autologous stem cell transplantation (ASCT). Although strong clinical trial evidence has supported the integration of lenalidomide into current treatment paradigms for NDMM, applying those paradigms to individual patients and determining which patients are most likely to benefit from lenalidomide treatment are more complex. In this paper, we utilize the available clinical trial evidence to provide recommendations for patient selection and lenalidomide dosing in both the first-line setting in patients ineligible for ASCT and the maintenance setting in patients who have undergone ASCT. In addition, we provide guidance on management of those adverse events that are most commonly associated with lenalidomide treatment, and consider the optimal selection and sequencing of next-line agents following long-term frontline or maintenance treatment with lenalidomide.

Neuroprotection by the Immunomodulatory Drug Pomalidomide in the Drosophila LRRK2WD40 Genetic Model of Parkinson's Disease

The search for new disease-modifying drugs for Parkinson's disease (PD) is a slow and highly expensive process, and the repurposing of drugs already approved for different medical indications is becoming a compelling alternative option for researchers. Genetic variables represent a predisposing factor to the disease and mutations in leucine-rich repeat kinase 2 (LRRK2) locus have been correlated to late-onset autosomal-dominant PD. The common fruit fly Drosophila melanogaster carrying the mutation LRRK2 loss-of-function in the WD40 domain (LRRK2^WD40), is a simple in vivo model of PD and is a valid tool to first evaluate novel therapeutic approaches to the disease. Recent studies have suggested a neuroprotective activity of immunomodulatory agents in PD models. Here the immunomodulatory drug Pomalidomide (POM), a Thalidomide derivative, was examined in the Drosophila LRRK2^WD40 genetic model of PD. Mutant and wild type flies received increasing POM doses (1, 0.5, 0.25 mM) through their diet from day 1 post eclosion, until postnatal day (PN) 7 or 14, when POM's actions were evaluated by quantifying changes in climbing behavior as a measure of motor performance, the number of brain dopaminergic neurons and T-bars, mitochondria integrity. LRRK2^WD40 flies displayed a spontaneous age-related impairment of climbing activity, and POM significantly and dose-dependently improved climbing performance both at PN 7 and PN 14. LRRK2^WD40 fly motor disability was underpinned by a progressive loss of dopaminergic neurons in posterior clusters of the protocerebrum, which are involved in the control of locomotion, by a low number of T-bars density in the presynaptic bouton active zones. POM treatment fully rescued the cell loss in all posterior clusters at PN 7 and PN 14 and significantly increased the T-bars density. Moreover, several damaged mitochondria with dilated cristae were observed in LRRK2^WD40 flies treated with vehicle but not following POM. This study demonstrates the neuroprotective activity of the immunomodulatory agent POM in a genetic model of PD. POM is an FDA-approved clinically available and well-tolerated drug used for the treatment of multiple myeloma. If further validated in mammalian models of PD, POM could rapidly be clinically tested in humans.

Lenalidomide normalizes tumor vessels in colorectal cancer improving chemotherapy activity

Background

Angiogenesis inhibition is a promising approach for treating metastatic colorectal cancer (mCRC). Recent evidences support the seemingly counterintuitive ability of certain antiangiogenic drugs to promote normalization of residual tumor vessels with important clinical implications. Lenalidomide is an oral drug with immune-modulatory and anti-angiogenic activity against selected hematologic malignancies but as yet little is known regarding its effectiveness for solid tumors. The aim of this study was to determine whether lenalidomide can normalize colorectal cancer neo-vessels in vivo, thus reducing tumor hypoxia and improving the benefit of chemotherapy.

Methods

We set up a tumorgraft model with NOD/SCID mice implanted with a patient-derived colorectal cancer liver metastasis. The mice were treated with oral lenalidomide (50 mg/Kg/day for 28 days), intraperitoneal 5-fluorouracil (5FU) (20 mg/Kg twice weekly for 3 weeks), combination (combo) of lenalidomide and 5FU or irrelevant vehicle. We assessed tumor vessel density (CD146), pericyte coverage (NG2; alphaSMA), in vivo perfusion capability of residual vessels (lectin distribution essay), hypoxic areas (HP2-100 Hypoxyprobe) and antitumor activity in vivo and in vitro.

Results

Treatment with lenalidomide reduced tumor vessel density (p = 0.0001) and enhanced mature pericyte coverage of residual vessels (p = 0.002). Perfusion capability of tumor vessels was enhanced in mice treated with lenalidomide compared to controls (p = 0.004). Accordingly, lenalidomide reduced hypoxic tumor areas (p = 0.002) and enhanced the antitumor activity of 5FU in vivo. The combo treatment delayed tumor growth (p = 0.01) and significantly reduced the Ki67 index (p = 0.0002). Lenalidomide alone did not demonstrate antitumor activity compared to untreated controls in vivo or against 4 different mCRC cell lines in vitro.

Conclusions

We provide the first evidence of tumor vessel normalization and hypoxia reduction induced by lenalidomide in mCRC in vivo. This effect, seemingly counterintuitive for an antiangiogenic compound, translates into indirect antitumor activity thus enhancing the therapeutic index of chemotherapy. Our findings suggest that further research should be carried out on synergism between lenalidomide and conventional therapies for treating solid tumors that might benefit from tumor vasculature normalization.

Approaches to Managing Safety With Lenalidomide in Hematologic Malignancies

Lenalidomide is an oral immunomodulatory agent approved in relapsed multiple myeloma with dexamethasone, for transfusion-dependent anemia in myelodysplastic syndrome associated with deletion 5q, and in relapsed/progressive mantle cell lymphoma following bortezomib. In recent clinical trials, lenalidomide has shown promising activity in hematologic malignancies, including chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL). Starting doses and dosing schedules vary by malignancy, with lenalidomide started at a lower dose for CLL than for NHL or multiple myeloma. Certain adverse events (AEs) are common across tumor types (e.g., neutropenia, thrombocytopenia, fatigue), whereas others are more often associated with CLL patients (e.g., tumor lysis syndrome and tumor flare reaction). Effective management requires awareness of these differences as well as appropriate prophylaxis, monitoring, and treatment of AEs. This article reviews the efficacy and safety of lenalidomide in CLL and NHL, focusing on approaches for the advanced practitioner to improve patient quality of life through optimal management of side effects. With these steps, lenalidomide can be administered safely, at the best starting doses and with minimal dose interruptions or reductions across hematologic malignancies.

Longitudinal analysis of patient-reported symptoms post-autologous stem cell transplant and their relationship to inflammation in patients with multiple myeloma

After autologous stem cell transplant (AuSCT), patients with multiple myeloma (MM) may receive lenalidomide maintenance therapy. This longitudinal study examined patient-reported symptom burden during the 3-9 months post-AuSCT and its association with maintenance therapy and circulating inflammatory markers. Fifty-one patients with MM rated symptom severity weekly using the MD Anderson Symptom Inventory MM module. When possible, blood for inflammatory marker assay was drawn at enrollment. Trajectory analysis identified clusters of patients who consistently reported higher or lower symptom severity. Although disease was relatively stable 3-9 months post-AuSCT, patients were not symptom-free: 35% were in the high-symptom group. Fatigue, pain, numbness/tingling, bone aches and muscle weakness were the most severe symptoms. Controlled for clinical variables, elevated baseline tumor necrosis factor-α (TNF-α) predicted high-symptom group membership (p = 0.014). Maintenance therapy and tumor response were not related to high symptom burden. Associations between inflammation and symptom burden in this exploratory study warrant further confirmatory study.

Thalidomide Embryopathy: An Enigmatic Challenge

Thalidomide remains one of the world’s most notorious drugs due to the severe birth defects it induced in children between 1957 and 1962. Yet, to some this drug is a lifesaver, as it now enjoys renaissance in the treatment for a wide range of conditions including leprosy, multiple myeloma, Behcet’s disease, and some cancers. However, thalidomide has also been linked to causing a new generation of thalidomide survivors in Brazil, where the drug is used to treat leprosy. Surprisingly how thalidomide causes birth defects and how it acts in the treatment of clinical conditions are still far from clear. In the past decade great strides in our understanding of the actions of the drug, as well as molecular targets, have been made. The purpose of this review is to look at the recent work carried out into understanding how thalidomide causes birth defects, it’s molecular targets and the challenges that remain to be elucidated. These challenges include identifying clinically relevant but nonteratogenic forms of the drug, and the mechanisms underlying phocomelia and species specificity.

Pomalidomide is nonteratogenic in chicken and zebrafish embryos and nonneurotoxic in vitro

Thalidomide and its analog, Lenalidomide, are in current use clinically for treatment of multiple myeloma, complications of leprosy and cancers. An additional analog, Pomalidomide, has recently been licensed for treatment of multiple myeloma, and is purported to be clinically more potent than either Thalidomide or Lenalidomide. Using a combination of zebrafish and chicken embryos together with in vitro assays we have determined the relative anti-inflammatory activity of each compound. We demonstrate that in vivo embryonic assays Pomalidomide is a significantly more potent anti-inflammatory agent than either Thalidomide or Lenalidomide. We tested the effect of Pomalidomide and Lenalidomide on angiogenesis, teratogenesis, and neurite outgrowth, known detrimental effects of Thalidomide. We found that Pomalidomide, displays a high degree of cell specificity, and has no detectable teratogenic, antiangiogenic or neurotoxic effects at potent anti-inflammatory concentrations. This is in marked contrast to Thalidomide and Lenalidomide, which had detrimental effects on blood vessels, nerves, and embryonic development at anti-inflammatory concentrations. This work has implications for Pomalidomide as a treatment for conditions Thalidomide and Lenalidomide treat currently.

Update on the role of autologous hematopoietic stem cell transplantation in multiple myeloma

Autologous stem cell transplantation is considered the standard of care for multiple myeloma patients aged < 65 years with no relevant comorbidities. The addition of drugs acting both on bone marrow microenvironment and on neoplastic plasma cells has significantly increased the proportion of patients achieving a complete remission after induction therapy, and these results are mantained after high-dose melphalan, leading to a prolonged disease control. Studies are being carried out in order to evaluate whether short term consolidation or long-term maintenance therapy can result into disease eradication at the molecular level thus increasing also patients survival. The efficacy of these new drugs has raised the issue of deferring the transplant after achiving a second response upon relapse. Another controversial point is the optimal treatment strategy for high-risk patients, that do not benefit from autologous stem cell transplantation and for whom the efficacy of new drugs is still matter of debate.

Secondary primary malignancies in multiple myeloma: an old NEMESIS revisited

The treatment of myeloma has undergone extraordinary improvements in the past half century. These advances have been accompanied by a concern for secondary primary malignancies (SPMs). It has been known for decades that extended therapy with alkylating chemotherapy agents, such as melphalan, carries an increased risk of therapy-related myelodysplastic syndrome and/or acute myeloid leukemia (t-MDS/AML), with a cumulative risk as high as 10–15%. High-dose chemotherapy with autologous stem cell support became widely accepted for myeloma in the 1990s. Despite the use of high doses of melphalan, the risk of t-MDS/AML with this procedure is estimated to be less than 5%, with much of this risk attributable to pretransplant therapy. Recently, lenalidomide has come under scrutiny for its possible association with SPMs. It is too soon to declare a causal relationship at this time, but there appears to be an increased number of SPMs in reports from several studies using lenalidomide maintenance. Current studies should be amended and future studies planned to better define the risk of SPMs and the risk factors and mechanisms for its development. Patients should be educated regarding this potential concern but the current use of lenalidomide should not generally be altered until further data are available.