Practical recommendations on the use of lenalidomide in the management of myelodysplastic syndromes

[Treatment of lower risk myelodysplastic syndromes]

For low-risk myelodysplastic syndromes, the goal of treatment is to correct cytopenias or their consequences. Erythropoiesis-stimulating agents have an important role in the management of anemia. In this chapter, we will detail the response to ESAs, the factors predictive of response to ESAs. However, the search for new therapeutic options for low-risk, ESA-resistant MDS remains necessary as the incidence of AML transformation of the patients is higher. We can retain luspatercept for MDS with excess ring of sideroblasts, lenalidomide, and some molecules currently being tested such as imetelstat or roxedustat. However, the search for new therapeutic options for ESA-resistant low-risk MDS remains necessary. We can use androgenotherapy or TPO agonists in limited access for symptomatic thrombocytopenia.

Targeting cereblon in hematologic malignancies

The protein cereblon (CRBN) is a substrate receptor of the cullin 4-really interesting new gene (RING) E3 ubiquitin ligase complex CRL4^CRBN. Targeting CRBN mediates selective protein ubiquitination and subsequent degradation via the proteasome. This review describes novel thalidomide analogs, immunomodulatory drugs, also known as CRBN E3 ubiquitin ligase modulators or molecular glues (avadomide, iberdomide, CC-885, CC-90009, BTX-1188, CC-92480, CC-99282, CFT7455, and CC-91633), and CRBN-based proteolysis targeting chimeras (PROTACs) with increased efficacy and potent activity for application in hematologic malignancies. Both types of CRBN-binding drugs, molecular glues, and PROTACs stimulate the interaction between CRBN and its neosubstrates, recruiting target disease-promoting proteins and the E3 ubiquitin ligase CRL4^CRBN. Proteins that are traditionally difficult to target (transcription factors and oncoproteins) can be polyubiquitinated and degraded in this way. The competition of CRBN neosubstrates with endogenous CRBN-interacting proteins and the pharmacology and rational combination therapies of and mechanisms of resistance to CRL4^CRBN modulators or CRBN-based PROTACs are described.

Case Report: Personalized Therapeutical Approaches with Lenalidomide in Del(5q): A Case Series

Myelodysplastic Syndrome (MDS) with del(5q) represents a unique WHO entity, which is often treated with lenalidomide according to standard clinical practice. Guidelines concerning treatment duration have thus far not been implemented, but rather comprise an indefinite therapy until loss of response. This review presents three red blood cell (RBC) transfusion-dependent MDS with del(5q) cases, starting with one rare case with an unbalanced translocation t(2;5), involving the breakpoint of del(5q) and loss of the 5q15-5q31 region. To the best of our knowledge, no comparable case has been described before with a response to lenalidomide. Strikingly, treatment-induced and maintained cytogenetic complete remission (cCR) in this patient. Furthermore, we report two cases of classical del(5q), in which lenalidomide was interrupted after a short period of lenalidomide therapy at the time cCR was achieved. Despite drug holiday cCR was maintained for seven and nine years, respectively. Then del(5q) re-emerged in the absence of novel molecular aberrations and re-treatment with lenalidomide could again achieve cCR in both cases. Together, this series presents three cases of personalized therapy of MDS with del(5q).

Myelodysplastic Syndromes: A New Decade

Myelodysplastic syndromes (MDS) are a group of heterogeneous clonal hematopoietic stem cell disorders. The 2020 Surveillance, Epidemiology, and End Results data demonstrates the incidence rate of MDS increases with age especially in those greater than 70 years of age. Risk stratification that impact prognosis, survival, and rate of acute myeloid leukemia (AML) transformation in MDS is largely dependent on revised International Prognostic Scoring System along with molecular genetic testing as a supplement. Low risk MDS typically have a more indolent disease course in which treatment is only initiated to ameliorate symptoms of cytopenias. In many, anemia is the most common cytopenia requiring treatment and erythroid stimulating agents, are considered first line. In contrast, high risk MDS tend to behave more aggressively for which treatment should be initiated rapidly with Hypomethylating Agents (HMA) being in the frontline. In those with high risk MDS and eligible, evaluation for allogeneic stem cell transplant should be considered as this is the only potential curative option for MDS. With the use of molecular genetic testing, a personalized approach to therapy in MDS has ensued. As the treatment landscape in MDS continues to flourish with novel targeted agents, we ambitiously seek to improve survival rates especially among the relapsed/refractory and transplant ineligible.

Anticancer Drug-induced Thyroid Dysfunction

Cancer immunotherapy and targeted therapy, though less toxic than conventional chemotherapy, can increase the risk of thyroid dysfunction. Immune checkpoint inhibitors render the cancer cells susceptible to immune destruction, but also predispose to autoimmune disorders like primary hypothyroidism as well as central hypothyroidism secondary to hypophysitis. Tyrosine kinase inhibitors act by blocking vascular endothelial growth factor receptors and their downstream targets. Disruption of the vascular supply from the inhibition of endothelial proliferation damages not only cancer cells but also organs with high vascularity like the thyroid. Interferon-α, interleukin-2 and thalidomide analogues can cause thyroid dysfunction by immune modulation. Alemtuzumab, a monoclonal antibody directed against the cell surface glycoprotein CD52 causes Graves' disease during immune reconstitution. Metaiodobenzylguanidine, combined with 131-iodine, administered as a radiotherapeutic agent for tumours derived from neural crest cells, can cause primary hypothyroidism. Bexarotene can produce transient central hypothyroidism by altering the feedback effect of thyroid hormone on the pituitary gland. Thyroid dysfunction can be managed in the usual manner without a requirement for dose reduction or discontinuation of the implicated agent. This review aims to highlight the effect of various anticancer agents on thyroid function. Early recognition and appropriate management of thyroid disorders during cancer therapy will help to improve treatment outcomes.

How we manage adults with myelodysplastic syndrome

The prognosis in Myelodysplastic syndromes (MDS), although recently refined by molecular studies, remains largely based on conventional prognostic scores [International Prognostic Scoring System (IPSS), revised IPSS], classifying patients into "lower risk" MDS (LR-MDS) and "higher risk" MDS (HR-MDS). In LR-MDS, treatment mainly aims at improving cytopenias, principally anaemia, while in HR-MDS it aims at delaying disease progression and prolonging survival. In LR-MDS without deletion 5q, anaemia is generally treated first by erythropoietic stimulating factors, while second line treatments are currently not approved [lenalidomide, hypomethylating agents (HMA), luspatercept] or rarely indicated (antithymocyte globulin). Lenalidomide has major efficacy in LR-MDS with deletion 5q. Allogeneic stem cell transplantation (allo-SCT) is sometimes considered in LR-MDS, and iron chelation can be considered when multiple red blood cell transfusions are required. Allo-SCT is the only potentially curative treatment for HR-MDS; however, it is rarely applicable. It is generally preceded by intensive chemotherapy (IC) or HMA in patients with excess of marrow blasts (especially if >10%). In other patients, HMA can improve survival. The role of new drugs, including venetoclax or, in case of specific mutations, IDH1 or IDH2 inhibitors, is investigated. IC is mainly indicated as a bridge to allo-SCT, in the absence of unfavourable karyotype.

Treatment of Lymphoid and Myeloid Malignancies by Immunomodulatory Drugs

Thalidomide and its derivatives (lenalidomide, pomalidomide, avadomide, iberdomide hydrochoride, CC-885 and CC-90009) form the family of immunomodulatory drugs (IMiDs). Lenalidomide (CC5013, Revlimid®) was approved by the US FDA and the EMA for the treatment of multiple myeloma (MM) patients, low or intermediate-1 risk transfusion-dependent myelodysplastic syndrome (MDS) with chromosome 5q deletion [del(5q)] and relapsed and/or refractory mantle cell lymphoma following bortezomib. Lenalidomide has also been studied in clinical trials and has shown promising activity in chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL). Lenalidomide has anti-inflammatory effects and inhibits angiogenesis. Pomalidomide (CC4047, Imnovid® [EU], Pomalyst® [USA]) was approved for advanced MM insensitive to bortezomib and lenalidomide. Other IMiDs are in phases 1 and 2 of clinical trials. Cereblon (CRBN) seems to have an important role in IMiDs action in both lymphoid and myeloid hematological malignancies. Cereblon acts as the substrate receptor of a cullin-4 really interesting new gene (RING) E3 ubiquitin ligase CRL4CRBN. This E3 ubiquitin ligase in the absence of lenalidomide ubiquitinates CRBN itself and the other components of CRL4CRBN complex. Presence of lenalidomide changes specificity of CRL4CRBN which ubiquitinates two transcription factors, IKZF1 (Ikaros) and IKZF3 (Aiolos), and casein kinase 1α (CK1α) and marks them for degradation in proteasomes. Both these transcription factors (IKZF1 and IKZF3) stimulate proliferation of MM cells and inhibit T cells. Low CRBN level was connected with insensitivity of MM cells to lenalidomide. Lenalidomide decreases expression of protein argonaute-2, which binds to cereblon. Argonaute-2 seems to be an important drug target against IMiDs resistance in MM cells. Lenalidomide decreases also basigin and monocarboxylate transporter 1 in MM cells. MM cells with low expression of Ikaros, Aiolos and basigin are more sensitive to lenalidomide treatment. The CK1α gene (CSNK1A1) is located on 5q32 in commonly deleted region (CDR) in del(5q) MDS. Inhibition of CK1α sensitizes del(5q) MDS cells to lenalidomide. CK1α mediates also survival of malignant plasma cells in MM. Though, inhibition of CK1α is a potential novel therapy not only in del(5q) MDS but also in MM. High level of full length CRBN mRNA in mononuclear cells of bone marrow and of peripheral blood seems to be necessary for successful therapy of del(5q) MDS with lenalidomide. While transfusion independence (TI) after lenalidomide treatment is more than 60% in MDS patients with del(5q), only 25% TI and substantially shorter duration of response with occurrence of neutropenia and thrombocytopenia were achieved in lower risk MDS patients with normal karyotype treated with lenalidomide. Shortage of the biomarkers for lenalidomide response in these MDS patients is the main problem up to now.

Safety profile of lenalidomide in patients with lower-risk myelodysplastic syndromes without del(5q): results of a phase 3 trial

The safety profile of lenalidomide use in lower-risk myelodysplastic syndromes (MDS) patients with del(5q) is well-established, but less is known in non-del(5q) patients. We provide safety data from a randomized, phase 3 trial evaluating lenalidomide in 239 patients with lower-risk non-del(5q) MDS ineligible/refractory to erythropoiesis-stimulating agents (ESAs). Compared with placebo, lenalidomide was associated with a higher incidence of grade 3-4 treatment-emergent adverse events (TEAEs; 86% vs. 44%), but not risk of infection (p = .817) or hemorrhagic events (p = 1.000). Grade 3-4 non-hematologic TEAEs were rare (the incidence of grade 3-4 pneumonia, e.g. was 5.6% in the lenalidomide group and 2.5% in the placebo group). Common grade 1-2 non-hematologic TEAEs did not require dose modifications or treatment discontinuation. Acute myeloid leukemia and second primary malignancies incidence was similar across treatment groups. Lenalidomide had a predictable and manageable safety profile in lower-risk non-del(5q) MDS patients ineligible/refractory to ESAs. Guidance on managing lenalidomide-related TEAEs is provided to help maintain patients on therapy to achieve maximum clinical benefit.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01029262.

Pomalidomide-induced hypothyroidism

Hypothyroidism is a recognized side effect of thalidomide drugs. We herein report a case of 83-year-old Irish female with a diagnosis of multiple myeloma and a background history of type 2 diabetes mellitus and hypertension. Our patient received pomalidomide and multiple courses of chemotherapy and achieved very good initial response for her multiple myeloma but subsequently she relapsed. She did not have any past history of thyroid disease or family history of thyroid disorders. Prior to treatment with pomalidomide, her thyroid function test was completely normal. She was commenced on pomalidomide in February 2017. Four weeks post treatment, she presented with worsening fatigue, and as a part of her workup, a thyroid function test was performed. Her free T4 was low at 7.2 pmol/L (reference range: 9.0–20.0) while her TSH was elevated at 44.7 mIU/L (reference range: 0.35–4.94). Pomalidomide treatment was terminated, and she was commenced on thyroid hormonal therapy replacement therapy with thyroxine with good clinical and biochemical response. Practitioners prescribing pomalidomide should be aware of this potential complication and patients who are receiving immunomodulatory drugs like pomalidomide should undergo regular thyroid hormone levels screen.

Practical Strategies for Management of Lenalidomide-Associated Cytopenias in Myelodysplastic Syndromes With del(5q)

CASE STUDY A male patient aged 67 years with a 2-year history of refractory anemia and myelodysplastic syndromes (MDS) with del(5q) started lenalidomide (Revlimid) treatment as a participant in the MDS-001 trial (List et al., 2005). At the time of the study, this patient had been transfusion-dependent since 2001, and at study entry he had received a total of 12 units of red blood cells (RBCs). The patient started lenalidomide at 25 mg daily for 21 days of each 28-day cycle on April 2, 2002. (Please note that as a result of subsequent trials, the approved starting dose for lenalidomide in patients with del[5q] MDS is 10 mg.) The patient developed treatment-related pancytopenia in the first 3 weeks of treatment (see Figure on next page). On day 24, lenalidomide was withheld. Platelet and white blood cell (WBC) counts were recovered during a 21-day period, and treatment was resumed with lenalidomide at 10 mg daily. During this initial dose interruption, the patient's hemoglobin level improved. He achieved RBC-transfusion independence (TI) during week 5 of treatment-his last RBC transfusion was on April 22, 2002. Bone marrow (BM) analysis, including fluorescence in situ hybridization, after 3 months of therapy, did not show the del(5q) abnormality. A repeat BM analysis after 57 months of treatment revealed minimal residual dyspoiesis, normal metaphase cytogenetics, and normal cell morphology. Subsequent BM biopsies showed transient trisomy 8 abnormalities but no del(5q) abnormality. The patient required one additional dose reduction during the first year of treatment. The patient did not require hospitalization during lenalidomide treatment but did have a history of seasonal allergies and a propensity for acute sinusitis. He received a single dose of pegfilgrastim (Neulasta) and a short course of antibiotics for active infections, generally one course of antibiotics per year. This patient continued on lenalidomide at 5 mg daily for 21 days of every 28-day cycle without further dose reduction. The patient achieved durable RBC-TI and continued to receive treatment for more than 11 years. The levels of hemoglobin, platelets, and WBCs for an 11-year period in this patient are shown in the Figure. This patient had one normal platelet count in 11 years of lenalidomide treatment but no bleeding episodes. The average platelet count in the 11-year period was 67 × 1,000/∝L (normal range, 150-425 × 1,000/∝L). Similarly, the WBC count remained below normal, with an average of 3.1 × 1,000/∝L (normal range, 3.4-10.4 × 1,000/∝L). He remained active and continued working as an aerospace engineer until age 75. This case demonstrates how effective management of cytopenias, through dose interruptions and modifications in the early weeks of treatment, helps to enable long-term lenalidomide treatment and a high quality of life. Despite the persistence of moderate, asymptomatic cytopenias, the patient was able to remain on lenalidomide therapy and maintained RBC-TI for more than 11 years. The patient died on October 4, 2014, at age 79.5, due to coronary artery disease and heart failure.

Treatment of low-risk myelodysplastic syndromes

The majority of myelodysplastic syndrome (MDS) patients belong to the International Prognostic Scoring System (IPSS) and IPSS-revised (IPSS-R) lower-risk categories. Their precise diagnostics and prognostic stratification is often a challenge, but may ensure the optimization of therapy. The availability of diverse treatment options has significantly improved the quality of life and survival of this group of patients. Anemia is the most relevant cytopenia in terms of frequency and symptoms in lower-risk MDS, and may be treated successfully with erythropoietic stimulating agents, provided a careful selection is performed on the basis of IPSS-R, endogenous erythropoietin levels, and transfusion independence. Doses and duration of therapy of erythropoietic-stimulating agents (ESAs) are critical to determine efficacy. In case a patient fails ESA treatment, the available options may include lenalidomide (approved for del5q positive cases), hypomethylating agents, and a rather large number of experimental agents, whose clinical trials should be offered to a larger number of MDS patients. The choice for second-line treatment must take into account biologic, cytogenetic, and molecular-identified characteristics of individual patients, as well as frailty and comorbidities. Other cytopenias are less frequently presenting as isolated. Specific therapy for thrombocytopenia has been proposed in experimental clinical trials with thrombomimetic agents that have shown good efficacy, but raised some safety concern. Although neutropenia is targeted symptomatically with growth factor supportive care, the immunosuppressive treatments are indicated mainly for pancytopenic, hypoplastic lower-risk MDS; they are not widely used because of their toxicity, despite the fact that they may induce responses. Finally, hematopoietic stem cell transplant is the curative option also for lower-risk MDS and timing should be carefully evaluated, balancing toxicity and the possibility of survival advantage. Finally, even when considered suitable for lower-risk MDS, transplant application is limited to the rarer fit and younger MDS patient.

Randomized Phase III Study of Lenalidomide Versus Placebo in RBC Transfusion-Dependent Patients With Lower-Risk Non-del(5q) Myelodysplastic Syndromes and Ineligible for or Refractory to Erythropoiesis-Stimulating Agents

PURPOSE

This international phase III, randomized, placebo-controlled, double-blind study assessed the efficacy and safety of lenalidomide in RBC transfusion-dependent patients with International Prognostic Scoring System lower-risk non-del(5q) myelodysplastic syndromes ineligible for or refractory to erythropoiesis-stimulating agents.

PATIENTS AND METHODS

In total, 239 patients were randomly assigned (2:1) to treatment with lenalidomide (n = 160) or placebo (n = 79) once per day (on 28-day cycles). The primary end point was the rate of RBC transfusion independence (TI) ≥ 8 weeks. Secondary end points were RBC-TI ≥ 24 weeks, duration of RBC-TI, erythroid response, health-related quality of life (HRQoL), and safety.

RESULTS

RBC-TI ≥ 8 weeks was achieved in 26.9% and 2.5% of patients in the lenalidomide and placebo groups, respectively (P < .001). Ninety percent of patients achieving RBC-TI responded within 16 weeks of treatment. Median duration of RBC-TI with lenalidomide was 30.9 weeks (95% CI, 20.7 to 59.1). Transfusion reduction of ≥ 4 units packed RBCs, on the basis of a 112-day assessment, was 21.8% in the lenalidomide group and 0% in the placebo group. Higher response rates were observed in patients with lower baseline endogenous erythropoietin ≤ 500 mU/mL (34.0% v 15.5% for > 500 mU/mL). At week 12, mean changes in HRQoL scores from baseline did not differ significantly between treatment groups, which suggests that lenalidomide did not adversely affect HRQoL. Achievement of RBC-TI ≥ 8 weeks was associated with significant improvements in HRQoL (P < .01). The most common treatment-emergent adverse events were neutropenia and thrombocytopenia.

CONCLUSION

Lenalidomide yields sustained RBC-TI in 26.9% of RBC transfusion-dependent patients with lower-risk non-del(5q) myelodysplastic syndromes ineligible for or refractory to erythropoiesis-stimulating agents. Response to lenalidomide was associated with improved HRQoL. Treatment-emergent adverse event data were consistent with the known safety profile of lenalidomide.

Durable response to lenalidomide in a patient with myelodysplastic syndrome associated with isolated 5q deletion and JAK2 V617F mutation despite discontinuation of treatment

Loss of a section of the long arm of chromosome 5, as a sole cytogenetic abnormality, characterizes a rare type of myelodysplastic syndrome [del(5q) MDS] and the co-existence of the JAK2 V617F mutation occurs in a small subset of these cases. Patients with isolated del(5q) MDS have a relatively favorable prognosis, with transformation to acute myeloid leukemia occurring in <10%, and their disease responds well to lenalidomide. However the optimal therapeutic approach for patients with del(5q) MDS in coexistence with the JAK2 V617F mutation, which is common to myeloproliferative neoplasms, remains to be elucidated. The present study reports a 77-year-old, transfusion-dependent female patient diagnosed with del(5q) MDS and a concomitant JAK2 V617F mutation. The patient was started on 10 mg lenalidomide daily for 21 days in a 28 day-cycle and within the first month of treatment, the patient became transfusion-independent. The only toxicity observed was grade 3 neutropenia, which was managed with transient treatment discontinuation and dose reduction on restart (5 mg). The patient achieved a complete cytogenetic and molecular response (normal karyotype and undetected JAK2 V617F mutation) within 6 months of treatment. However, 12 months post treatment initiation and while on hematological, cytogenetic and molecular response, the patient was unwilling to continue on treatment and lenalidomide was discontinued. The patient remains in hematological response, which lasts for >5 years despite treatment discontinuation. The present case highlights the coexistence of the JAK2 V617F mutation in del(5q) MDS and suggests that lenalidomide treatment is beneficial and effective for these patients, leading to complete hematological, cytogenetic and molecular response. Hematological response may be sustained for long periods of time, even following the discontinuation of the treatment.

Lenalidomide with or without erythropoietin in transfusion-dependent erythropoiesis-stimulating agent-refractory lower-risk MDS without 5q deletion

After failure of erythropoiesis-stimulating agents (ESAs), lenalidomide (LEN) yields red blood cell (RBC) transfusion independence (TI) in 20-30% of lower-risk non-del5q myelodysplastic syndrome (MDS). Several observations suggest an additive effect of ESA and LEN in this situation. We performed a randomized phase III study in 131 RBC transfusion-dependent (TD, median transfusion requirement six RBC units per 8 weeks) lower-risk ESA-refractory non-del5q MDS. Patients received LEN alone, 10 mg per day, 21 days per 4 weeks (L arm) or LEN (same schedule) + erythropoietin (EPO) beta, 60,000 U per week (LE arm). In an intent-to-treat (ITT) analysis, erythroid response (HI-E, IWG 2006 criteria) after four treatment cycles (primary end point) was 23.1% (95% CI 13.5-35.2) in the L arm and 39.4% (95% CI 27.6-52.2) in the LE arm (P=0.044), while RBC-TI was reached in 13.8 and 24.2% of the patients in the L and LE arms, respectively (P=0.13). Median response duration was 18.1 and 15.1 months in the L and LE arms, respectively (P=0.47). Side effects were moderate and similar in the two arms. Low baseline serum EPO level and a G polymorphism of CRBN gene predicted HI-E. Combining LEN and EPO significantly improves erythroid response over LEN alone in lower-risk non-del5q MDS patients with anemia resistant to ESA.

Long-Term Response in a Patient with del(5q) Myelodysplastic Syndrome Who Discontinued Lenalidomide and Obtained a Good Response and Tolerance to Rechallenge

Background

The introduction of the immunomodulatory drug lenalidomide has revolutionized the treatment of patients with myelodysplastic syndromes (MDS) and deletion of the long arm of chromosome 5. Treatment with lenalidomide results in transfusion independence in the majority of patients, but some questions remain unresolved, among them the duration of treatment. Moreover, a number of unexpected long-term remissions in patients who stopped lenalidomide for various reasons have been observed.

Case Report

We report the case of a 60-year-old Caucasian male with deletion of the long arm of chromosome 5 and International Prognostic Scoring System (IPSS)-defined low-risk MDS who was treated with lenalidomide, achieving complete cytogenetic remission and erythroid response. After tapering off and interrupting the treatment, the patient relapsed and showed a new response by lenalidomide retreatment. Six years after the initial treatment, we registered a durable erythroid long-term response and good tolerance, but there was no evidence of a very profound cytogenetic response compared to using lenalidomide as a first-line treatment. Cytogenetic and fluorescence in situ hybridization together with hemoglobin level, mean corpuscular volume (MCV) and vitamin B₁₂ level helped us to monitor the patient response; during the various phases of lenalidomide treatment, MCV and vitamin B₁₂ normalization correlated with good response.

Conclusion

Lenalidomide interruption and rechallenge in some 5q– MDS patients, with low risk according to the IPSS, is safe and feasible but does not result in a profound cytogenetic response.

Initial transfusion intensity predicts survival in myelodysplastic syndrome

We evaluated 52 patients with myelodysplastic syndrome (MDS) who had received at least one red blood cell (RBC) transfusion. In the 4-week period following the first transfusion, 24 patients (group 1) required no transfusion, while 28 (group 2) required transfusion of two or more units of RBCs. Survival was greater in group 1 (440 weeks vs. 167 weeks, p < 0.01), even when only international prognostic scoring system (IPSS) low and intermediate-1 risk patients were analyzed (median overall survival 491 vs. 170 weeks, p < 0.05), independent of age, IPSS and progression to acute myeloid leukemia (AML). The intensity of transfusion required in the first few weeks after the first transfusion predicts disease severity and correlates with survival.

A highly sensitive polyclonal antibody-based ELISA for therapeutic monitoring and pharmacokinetic studies of lenalidomide

This article describes, for the first time, a highly sensitive and specific enzyme-linked immunosorbent assay (ELISA) for therapeutic monitoring and pharmacokinetic studies of lenalidomide (LND), the potent drug for treatment of multiple myeloma (MM). The assay employed a polyclonal antibody that specifically recognizes LND with high affinity, and LND conjugate of bovine serum albumin (LND-BSA) immobilized onto microplate wells as a solid phase. The assay involved a competitive binding reaction between LND, in plasma sample, and the immobilized LND-BSA for the binding sites on a limited amount of the anti-LND antibody. The assay limit of detection was 0.05 ng/mL and the effective working range at relative standard deviations (RSD) of ≤5% was 0.1-20 ng/mL. Analytical recovery of LND from spiked plasma was 100.98 ± 3.05. The precisions of the assay were satisfactory; RSD was 2.96-6.67% and 4.46-7.14%, for the intra- and inter-assay precision, respectively. The procedure is convenient, and one can analyze ∼200 samples per working day, facilitating the processing of large-number batch of samples in clinical laboratories. The proposed ELISA has a great value in routine analysis of LND for its therapeutic monitoring and pharmacokinetic studies.

Optimizing management of ruxolitinib in patients with myelofibrosis: the need for individualized dosing

Ruxolitinib, an oral JAK1 and JAK2 inhibitor, is approved in the US for patients with intermediate or high-risk myelofibrosis (MF), a chronic neoplasm associated with aberrant myeloproliferation, progressive bone marrow fibrosis, splenomegaly, and burdensome symptoms. Phase III clinical studies have shown that ruxolitinib reduces splenomegaly and alleviates MF-related symptoms, with concomitant improvements in quality of life measures, for the overwhelming majority of treated patients. In addition, ruxolitinib provided an overall survival advantage as compared with either placebo or what was previously considered best available therapy in the two phase III studies. The most common adverse events with ruxolitinib treatment include dose-dependent anemia and thrombocytopenia, which are expected based on its mechanism of action. Experience from the phase III studies shows that these hematologic events can be managed effectively with dose modifications, temporary treatment interruptions, as well as red blood cell transfusions in the case of anemia and, importantly, are rarely cause for permanent treatment discontinuation. This review summarizes data supporting appropriate individualized patient management through careful monitoring of blood counts and dose titration as needed in order to maximize treatment benefit.

Deletion 5q MDS: molecular and therapeutic implications

Heterozygous, interstitial deletions of chromosome 5q are the most common cytogenetic abnormality in myelodysplastic syndromes (MDS). This chromosomal abnormality is associated with a consistent clinical phenotype, the 5q- syndrome, in a subset of patients, and therapeutic sensitivity to the drug lenalidomide. No genes on chromosome 5q undergo recurrent homozygous inactivation in MDS patients. Instead, haploinsufficiency for key genes powerfully alters hematopoiesis, leading to the MDS phenotype in patients with del(5q). Haploinsufficiency for the RPS14 gene leads to activation of the p53 pathway and the macrocytic anemia characteristic of this disorder, and loss of p53 rescues erythropoiesis and facilitates clonal progression. Other genes, as well as miR-145 and miR-146a, contribute to aberrant megakaryopoiesis and a selective advantage for the del(5q) clone. The integrated effects of haploinsufficiency for these key genes, in aggregate, lead to the full phenotype of the disorder.

How we treat lower-risk myelodysplastic syndromes

Lower-risk myelodysplastic syndromes (MDSs) are defined as having low or intermediate 1 risk by the International Prognostic Scoring System and are characterized mainly by anemia in most cases. Supportive care--primarily red blood cell transfusions--remains an important component of their treatment, but exposes patients to insufficient correction of anemia, alloimmunization, and organ iron overload (for which the role of iron chelation remains debated). Treatment aimed at preventing anemia recurrence should therefore be used whenever possible. Erythropoiesis stimulating agents remain the first-line treatment of anemia in most lower-risk MDS without del(5q), whereas anemia of low-risk MDS with del 5q responds to lenalidomide in two-thirds of the cases, but this drug should be used cautiously because profound cytopenias may occur initially. Treatment after failure of those first-line therapies are disappointing overall, with many patients eventually requiring long-term transfusions, but encouraging results have been reported with hypomethylating agents and lenalidomide. Selected patients respond to antithymocyte globulins, and thrombopoietin receptor agonists are under investigation in lower-risk MDS with thrombocytopenia. Some patients, while remaining at a "lower risk" MDS level, have severe cytopenias and/or poor prognostic factors, found using newer prognostic parameters, or resistance to treatment, making them urgent candidates for more intensive approaches, including allogeneic stem cell transplantation.

Trace determination of lenalidomide in plasma by non-extractive HPLC procedures with fluorescence detection after pre-column derivatization with fluorescamine

BACKGROUND

Lenalidomide (LND) is a new potent drug used for treatment of multiple myeloma. For its pharmacokinetic studies and therapeutic monitoring, a proper analytical method was required.

RESULTS

In this study, a non extractive and simple pre-column derivatization procedures have been proposed, for the for trace determination of lenalidomide (LND) in human plasma by HPLC with fluorescence detection. Plasma samples were treated with acetonitrile for protein precipitation then treated with copper acetate to form stable complexes with the biogenic amines and mask their interference with the derivatization reaction of LND. Treated plasma samples containing LND was derivatized with fluorescamine (FLC) in aqueous media at ambient temperature. Separation of the derivatized LND was performed on Hypersil BDS C18 column (250 × 4.6 mm, 5 μm particle size) using a mobile phase consisting of phosphate buffer (pH 4):methanol: tetrahydrofuran (70:10:20, v/v) at a flow rate of 1.0 mL/min. The derivatized samples were monitored at an emission wavelength of 495 nm after excitation at a wavelength of 382 nm. Under the optimum chromatographic conditions, a linear relationship with good correlation coefficient (r = 0.9997, n = 9) was found between the peak area and LND concentrations in the range of 2-100 ng/mL. The limits of detection and quantitation were 0.8 and 2.30 ng/mL, respectively. The intra- and inter-assay precisions were satisfactory and the accuracy of the method was proved. The recovery of LND from the spiked human plasma was 99.30 ± 2.88.

CONCLUSIONS

The proposed method had high throughput as the analysis involved simple sample pre-treatment procedure and a relatively short run-time (< 15 min). The results demonstrated that the method would have a great value when it is applied in the therapeutic monitoring and pharmacokinetic studies for LND.

Synthesis of hapten and preparation of specific polyclonal antibody with high affinity for lenalidomide, the potent drug for treatment of multiple myeloma

BACKGROUND

For therapeutic monitoring and pharmacokinetic studies of lenalidomide (LND), the potent drug for treatment of multiple myeloma (MM), a specific antibody was required for the development of a sensitive immunoassay system for the accurate determination of LND in plasma.

RESULTS

In this study, a hapten of LND (N-glutaryl-LND) was synthesized by introducing the glutaryl moiety, as a spacer, into the primary aromatic amine site of the LND molecular structure. The structure of the hapten (G-LND) was confirmed by mass, 1H-NMR, and 13C spectrometric techniques. G-LND was coupled to each of bovine serum albumin (BSA) and keyhole limpet hemocyanin (KLH) proteins by ethyl-3-(3-dimethylaminopropyl) carbodiimide as a coupling reagent. LND-KLH conjugate was used as an immunogen. Four female 2-3 months old New Zealand white rabbits were immunized with an emulsion of LND-KLH with Freund`s adjuvant. The immune response of the rabbits was monitored by direct enzyme-linked immunosorbent assay (ELISA) using LND-BSA immobilized onto microwell plates as a solid phase. The rabbit that showed the highest antibody titer and affinity to LND was scarified and its sera were collected. The IgG fraction was isolated and purified by affinity chromatography on protein A column. The specificity of the purified antibody for LND was evaluated by indirect competitive ELISA using dexamethasone as a competitor as it is used with LND in a combination therapy.

CONCLUSIONS

The high affinity of the antibody (IC50 = 10 ng/mL) will be useful in the development of an immunoassay system for the determination of plasma LND concentrations. Current research is going to optimize the assay conditions and validate the procedures for the routine application in clinical laboratories.

Infections in myelodysplastic syndromes

Myelodysplastic syndromes are associated with a risk of severe infections. While neutropenia is likely to be the main predisposing factor, several other immune defects have been reported, including impaired neutrophil function, B-, T- and NK-cell defects and the possible consequences of iron overload due to red blood cell transfusions. The advanced age of most patients, their frequent comorbidities, and the fact that drugs such as hypomethylating agents and lenalidomide, which are effective in myelodysplastic syndromes but can transiently worsen neutropenia, may increase the risk of infection and their severity in this context. The majority of infections in myelodysplastic syndromes are bacterial, while the incidence of fungal infections is not well known and viral infections seem to be rare. No prophylactic measures against infections have demonstrated efficacy in myelodysplastic syndromes. However, pending more data, we propose here some recommendations for the management of patients with myelodysplastic syndromes. In the future, an important contribution can be made by prospective trials testing the efficacy of prophylactic and therapeutic approaches to infection in these patients, especially in the context of the new drugs available for myelodysplastic syndromes.

The clinical safety of lenalidomide in multiple myeloma and myelodysplastic syndromes

INTRODUCTION

Lenalidomide is an IMiDs® oral immunomodulatory compound developed for the treatment of patients with multiple myeloma (MM) and myelodysplastic syndromes (MDS). Long-term continuous treatment with lenalidomide beyond first response may be important to optimize responses and delay relapse.

AREAS COVERED

This review summarizes the lenalidomide mechanism of action, pharmacodynamics, key clinical studies with a focus on safety and post-marketing surveillance data. The necessity for early adverse-event management, including dose modifications for neutropenia and thrombocytopenia, and venous thromboembolism prophylaxis, where applicable, in order to maintain patients on treatment and achieve optimal efficacy, is discussed. Secondary primary malignancies in MM and progression to acute myeloid leukemia in MDS patients in the context of lenalidomide treatment are also discussed. Finally, as lenalidomide is renally excreted, the requirement for dose adjustment according to creatinine clearance is discussed.

EXPERT OPINION

Lenalidomide is highly effective and generally well tolerated. Most adverse events occur early during the course of treatment and are manageable. Lenalidomide is not associated with peripheral neuropathy and has a lack of cumulative toxicity, making it an effective treatment option for long-term use in the management of MM and low/intermediate-1-risk MDS, specifically with chromosome 5q deletion with or without other cytogenetic abnormalities.

Thyroid dysfunction from antineoplastic agents

Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%-50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient's quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents.

Treatment by Lenalidomide in lower risk myelodysplastic syndrome with 5q deletion--the GFM experience

We treated 95 RBC transfusion dependent lower risk MDS with del 5q with Lenalidomide (10mg/day, 3 weeks/4 weeks). Median age was 70.4, median interval from diagnosis 29 months. IPSS was low in 31% and intermediate-1 in 69% patients. Del 5q was isolated, with 1 additional and >1 additional abnormality in 79%, 14%, and 6% patients, respectively. 62 (65%) patients achieved transfusion independence (TI). The only significant factor predicting TI was baseline platelet count >150 G/L and platelet decrease by at least 50% during the first weeks of treatment (p=0.001). Grade III-IV neutropenia and thrombocytopenia were seen in 74% and 37.9% of the cases, respectively, and 3 deaths were attributed to cytopenias. Eight (8%) patients developed deep venous thrombosis (DVT). Platelet decrease by less than 50% predicted a higher risk of DVT. Only 6 patients (6.3%) patients progressed to AML, but median follow-up time was short (18 months). We confirm the high rate of TI with Lenalidomide in lower risk MDS with del 5q. Very close patient monitoring for cytopenias and DVT is mandatory, especially during the first weeks of treatment.

Thyroid abnormalities in patients treated with lenalidomide for hematological malignancies: results of a retrospective case review

Lenalidomide is an antiangiogenic drug associated with hypothyroidism. We describe a case-series of lenalidomide use in hematological cancers and the prevalence of thyroid abnormalities. We reviewed medical records of patients treated with lenalidomide at a single center form 2005 to 2010 and extracted demographic, clinical, and laboratory data. Of 170 patients with confirmed lenalidomide use (age 64.9 ± 15 years), 148 were treated for multiple myeloma and 6% had thyroid abnormalities attributable only to lenalidomide. In patients with a previous diagnosis of thyroid dysfunction, the addition of lenalidomide therapy was associated with a higher incidence of subsequent TFTF abnormality (17%) as compared to patients with no previous diagnosis of thyroid dysfunction (6%) (P=0.0001). Many patients (44%) with pre-existing disease and a change in thyroid function before or while on lenalidomide had no further follow-up of their thyroid abnormalities, Of 20 patients who did not undergo any thyroid function testing either before starting or while on lenalidomide for a median of 9.4 months (± 6.5), 35% developed new symptoms compatible with hypothyroidism, including worsened fating, constipation or cold intolerance. Symptoms of thyroid dysfunction overlap with side effects of lenalidomide. Thyroid hormone levels are not regularly evaluated in patients on lenalidomide. While on this treatment, thyroid abnormalities can occur in patients with no previous diagnoses and in patients with pre-existing abnormalities. Because symptoms of thyroid dysfunction could be alleviated by appropriate treatment, thyroid function should be evaluated during the course of lenalidomide to improve patients quality of life.

Immunomodulating drugs in myelodysplastic syndromes

Based on immune mechanisms that appear to play an important role in the pathophysiology of at least part of the lower-risk myelodysplastic syndrome (MDS), the immunomodulating drug (IMID) thalidomide and its derivative lenalidomide (LEN) have been used in MDS, principally in lower-risk MDS. LEN has become the first-line US Food and Drug Administration (FDA)-approved treatment for lower-risk MDS with 5q deletion (del5q), in which its main mechanism of action is probably a direct cytotoxic activity on the del5q clone. This possibly specific effect is currently being investigated in higher-risk MDS-and even acute myeloid leukemia (AML)-with del5q, but LEN has also demonstrated some efficacy in MDS and AML without del5q. Thalidomide also has some activity in lower-risk MDS without del5q, but its side effects limit its practical use in these patients.

Management of patients with chronic lymphocytic leukemia treated with lenalidomide

Lenalidomide is an immunomodulatory drug that has shown preliminary activity in the treatment of chronic lymphocytic leukemia (CLL). Much is known about the safety profile of lenalidomide from experience in other hematologic malignancies, such as myelodysplastic syndromes and multiple myeloma. In addition to the known adverse effects associated with lenalidomide (e.g., myelosuppression, rash, fatigue), some unique effects (e.g., tumor flare reactions, tumor lysis syndrome) have arisen during clinical studies of CLL. Typical signs of tumor flare reactions include early onset of painful enlargement of the lymph nodes or spleen, with or without low-grade fever, rash, and bone pain. Management may require nonsteroidal anti-inflammatory drugs or a short course of corticosteroids. Dose delays or reductions usually are not required for tumor flare reactions. Signs of tumor lysis syndrome may include shortness of breath, peripheral edema, generalized weakness, sweating, fever, and tachycardia. Untreated tumor lysis syndrome can result in renal impairment and congestive heart failure. Careful monitoring and appropriate management of treatment-related side effects can help ensure that patients with CLL achieve maximum therapeutic benefit from lenalidomide therapy.

Lenalidomide for treatment of myelodysplastic syndromes: current status and future directions

Lenalidomide was approved by the US Food and Drug Administration (FDA) for treatment of transfusion-dependent lower-risk myelodysplastic syndrome patients with deletion (del) (5q) alone or with additional karyotype abnormalities. The approval was based on high rates of prolonged transfusion independence and complete cytogenetic response in this subset. In lower-risk non-del(5q) patients, meaningful erythroid responses also were reported with a low frequency of cytogenetic improvement, although inferior to that observed in the del(5q) patients. There is now a better understanding of the mechanism of the karyotype-dependent drug action, explaining the disparate response rates and frequency of myelosuppression. In del(5q) patients, lenalidomide suppresses the clone by inhibiting the nuclear sequestration of the haplodeficient cell cycle regulatory protein cdc25c, thereby promoting selective G2 arrest and apoptosis. In non-del(5q) patients, lenalidomide enhances erythropoietin receptor signaling. Future directions include use of biologic and molecular markers as predictive tools to select patients and use of combination strategies to overcome resistance to lenalidomide in del(5q) patients or enhance erythropoiesis in non-del 5 patients.

An update on the treatment of myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a group of heterogeneous clonal disorders of myeloid hematopoietic stem cells affecting about 300,000 people worldwide. Ineffective hematopoiesis and clonal proliferation result in significant cytopenias in affected individuals. Patients are categorized into risk groups (i.e., low, intermediate [1 and 2], and high) based on severity of cytopenias, cytogenetic abnormalities, and the presence of bone marrow blasts. The only potentially curative treatment for MDS is hematopoietic stem cell transplantation, which often is not an option because of advanced age at diagnosis (median age = 76 years). Several alternative treatments to hematopoietic stem cell transplantation show great promise. For low- and intermediate-1-risk MDS, the novel antitumor immunomodulatory agent lenalidomide is approved for patients with del(5q), and two different hypomethylating agents, azacitidine and decitabine, are approved for intermediate-2- and high-risk MDS. Trial results have increased the understanding of these treatments, alone or in combination with other therapies. Effective treatment often requires at least three to six months to achieve a clinical response. In the meantime, or in addition to active therapy, supportive care has a positive effect on quality of life. Greater understanding of the factors affecting MDS treatment options will assist oncology nurses in facilitating the optimal combination of treatment, supportive care, and management of adverse events.

The clinical utility of lenalidomide in multiple myeloma and myelodysplastic syndromes

PURPOSE

the pharmacology, pharmacokinetics, pharmacodynamics, clinical utility, adverse effects, dosage, and cost of lenalidomide are reviewed.

SUMMARY

lenalidomide is a thalidomide analogue approved for treatment of myelodysplastic syndromes (MDS) associated with a cytogenetic 5q deletion. In combination with dexamethasone, lenalidomide has been approved by the FDA in the United States for the treatment of relapsed or refractory multiple myeloma, and is sometimes used for induction therapy. Although the precise mechanism of action of lenalidomide remains unknown, it does exhibit antineoplastic and immunomodulatory properties. Lenalidomide is quickly absorbed after oral administration and is renally eliminated. In patients with myelodysplatic syndromes, lenalidomide reduces the need for transfusion. In patients with refractory or relapsed multiple myeloma, lenalidomide in combination with dexamethasone demonstrated a significantly longer time to tumor progression compared to placebo plus dexamethasone. Lenalidomide in combination with dexamethasone also elicited an objective response from patients with newly diagnosed symptomatic multiple myeloma. Treatment with lenalidomide was associated with neutropenia, thrombocytopenia, constipation, pruritus, and fatigue. Due to the teratogenic nature of thalidomide, lenalidomide must be obtained through a restrictive distribution program. The initial daily dosing of lenalidomide is 10 mg for MDS with a 5q deletion and 25 mg for relapsed or refractory multiple myeloma. Dose modifications are required for renal impairment and grade 3-4 adverse events.

CONCLUSION

lenalidomide is an effective agent for the treatment of MDS with a 5q deletion and relapsed or refractory multiple myeloma.

Effect of lenalidomide therapy on hematopoiesis of patients with myelodysplastic syndrome associated with chromosome 5q deletion

BACKGROUND

Lenalidomide improves erythropoiesis in patients with low/intermediate-1 risk myelodysplastic syndrome and interstitial deletion of the long arm of chromosome 5 [del(5q)]. The aim of this study was to explore the effect of lenalidomide treatment on the reserves and functional characteristics of bone marrow hematopoietic progenitor/precursor cells, bone marrow stromal cells and peripheral blood lymphocytes in patients with low/intermediate-1 risk myelodysplastic syndrome with del(5q).

DESIGN AND METHODS

We evaluated the number and clonogenic potential of bone marrow erythroid/myeloid/megakaryocytic progenitor cells using clonogenic assays, the apoptotic characteristics and adhesion molecule expression of CD34(+) cells by flow cytometry, the hematopoiesis-supporting capacity of bone marrow stromal cells using long-term bone marrow cultures and the number and activation status of peripheral blood lymphocytes in ten patients with low/intermediate-1 risk myelodysplastic syndrome with del(5q) receiving lenalidomide.

RESULTS

Compared to baseline, lenalidomide treatment significantly decreased the proportion of bone marrow CD34+ cells, increased the proportion of CD36(+)/GlycoA(+) and CD36(-)/GlycoA(+) erythroid cells and the percentage of apoptotic cells within these cell compartments. Treatment significantly improved the clonogenic potential of bone marrow erythroid, myeloid, megakaryocytic colony-forming cells and increased the proportion of CD34(+) cells expressing the adhesion molecules CD11a, CD49d, CD54, CXCR4 and the SLAM antigen CD48. The hematopoiesis-supporting capacity of bone marrow stroma improved significantly following treatment, as demonstrated by the number of colony-forming cells and the level of stromal-derived factor-1 alpha and intercellular adhesion molecule-1 in long-term bone marrow culture supernatants. Lenalidomide treatment also increased the proportion of activated peripheral blood T lymphocytes.

CONCLUSIONS

The beneficial effect of lenalidomide in patients with lower risk myelodysplastic syndrome with del(5q) is associated with significant increases in the proportion of bone marrow erythroid precursor cells and in the frequency of clonogenic progenitor cells, a substantial improvement in the hematopoiesis-supporting potential of bone marrow stroma and significant alterations in the adhesion profile of bone marrow CD34(+) cells.

Anaemia in the elderly

Anaemia is highly prevalent in elderly populations, particularly in long term care facilities and geriatric wards. Even mild anaemia is associated with adverse health outcomes. Although senescence is considered to be a contributing factor, underlying pathology always has to be thoroughly explored. The most frequent etiologies of anaemia in the elderly are anaemia of chronic disease/inflammation; iron, folate and cobalamin deficiency; and myelodysplastic syndrome. Multiple concomitant etiologies are frequently present. The diagnostic workup is straightforward, not very invasive and should be done systematically. Nutrient deficiencies require complete workup and cure. Anaemia of chronic disease/inflammation ideally is taken care of by treating the underlying disease. If this is not possible and if glomerular filtration rate is significantly decreased, treatment with erythropoietin should be considered. Most cases of myelodysplastic syndrome will benefit from supportive care, but a specific subgroup responds particularly well to oral thalidomide analogues. Transfusions should be avoided.