Pharmacology of thalidomide

Anti-emetic effects of thalidomide: Evidence, mechanism of action, and future directions

The rationale for using thalidomide (THD) as a treatment for nausea and vomiting during pregnancy in the late 1950s appears to have been based on its sedative or hypnotic properties. In contrast to contemporaneous studies on the anti-emetic activity of phenothiazines, we were unable to identify publications reporting preclinical or clinical evaluation of THD as an anti-emetic. Our survey of the literature revealed a clinical study in 1965 showing THD reduced vomiting in cancer chemotherapy which was substantiated by similar studies from 2000, particularly showing efficacy in the delayed phase of chemotherapy-induced nausea and vomiting. To identify the mechanism(s) potentially involved in thalidomide's anti-emetic activity we reviewed its pharmacology in the light of nausea and vomiting mechanisms and their pharmacology with a particular emphasis on chemotherapy and pregnancy. The process identified the following potential mechanisms: reduced secretion of Growth Differentiation Factor 15, suppression of inflammation/prostaglandin production, downregulation of cytotoxic drug induced upregulation of iNOS, and modulation of BK (KCa1.1) channels and GABAA/glutamate transmission at critical points in the emetic pathways (nucleus tractus solitarius, area postrema). We propose ways to investigate these hypothesized mechanisms and discuss the associated challenges (e.g., objective quantification of nausea) in addition to some of the more general aspects of developing novel drugs to treat nausea and vomiting.

Thalidomide in multiple myeloma--clinical trials and aspects of drug metabolism and toxicity

BACKGROUND

After the tragic events in the early 1960s, thalidomide has re-emerged as therapeutic for multiple myeloma (MM). It was first approved for the treatment of erythema nodosum leprosum, and is now under evaluation for hematologic and non-hematologic disorders. Its complex mechanism of action is not fully understood; however extensive preclinical studies in MM have revealed its antiangiogenic and immunomodulatory properties.

OBJECTIVE

In this review, we focus on the importance and toxicity of thalidomide in today's clinical use.

METHODS

Key preclinical and clinical trials available as well as data on the pharmacokinetics and pharmacodynamics of thalidomide in humans are summarized.

CONCLUSIONS

Thalidomide is widely used as first-line treatment and in relapsed/refractory MM. The most common side effects are fatigue, constipation and peripheral neuropathy, and careful monitoring is required to avoid fetal exposure.

The role of the bone marrow microenvironment in the pathophysiology of myeloma and its significance in the development of more effective therapies

Multiple myeloma (MM) is viewed as a prototypic disease state for the study of how neoplastic cells interact with their local bone marrow (BM) microenvironment. This interaction reflects not only the osteo-tropic clinical behavior of MM and the clinical impact of the lytic bone lesions caused by its tumor cells but also underlines the broadly accepted notion that nonneoplastic cells of the BM can attenuate the activity of cytotoxic chemotherapy and glucocorticoids. This article summarizes the recent progress in characterization, at the molecular and cellular levels, of how the BM milieu interacts with MM cells and modifies their biologic behavior.

Multiple myeloma: a prototypic disease model for the characterization and therapeutic targeting of interactions between tumor cells and their local microenvironment

The interaction between tumor cells and the local milieu where are homing has recently become the focus of extensive research in a broad range of malignancies. Among them, multiple myeloma (MM) is now recognized as a prototypical tumor model for the characterization of these interactions. This is due not only to the propensity of MM cells to target the skeleton and form lytic bone lesions, but because interactions of MM cells with normal cells of the bone milieu can attenuate the anti-tumor activity of conventional therapies, such as glucocorticoids and standard cytotoxic agents, including alkylators. Herein, we highlight the recent advances in our understanding of cellular and molecular mechanisms of interactions between MM cells and their milieu. Particular emphasis is placed on the interface between MM cells and normal cell compartments of the BM, especially bone marrow stromal cells (BMSCs), and on the development of a series of new classes of therapeutic agents, including the proteasome inhibitor bortezomib, thalidomide and lenalidomide, which counteract specific aspects of those MM-BM interactions. The significant clinical activity of these novel therapies has not only led to a new era in the therapeutic management of this disease, but also underscored the importance of comprehensively characterizing the role of the local microenvironment in the pathophysiology of human neoplasias.

Thalidomide in multiple myeloma: past, present and future

Thalidomide was introduced in the treatment of multiple myeloma in the late 1990s. Following the initial results, which demonstrated dramatic response rates in heavily pretreated patients, a number of Phase II studies have confirmed the efficacy of this agent in relapsed patients. However, a high incidence of side effects at the dosage initially recommended (400 mg/day) justified further studies with lower doses of thalidomide given alone or in combination with dexamethasone or chemotherapy. Thalidomide is currently considered as one of the most active agents in relapsed myeloma. Recent studies have demonstrated that thalidomide could also be used as part of frontline therapy. The combination of thalidomide plus dexamethasone as initial therapy appears to be slightly superior to dexamethasone alone or to vincristine–doxorubicine–dexamethasone, but with an increased risk of deep vein thrombosis. Maintenance with thalidomide after autologous transplantation appears to increase the complete remission rate and to prolong progression-free survival. The combination of thalidomide plus melphalan and prednisone is superior to the classical melphalan–prednisone regimen in elderly patients, and will become the standard of care. Thalidomide has been registered in the USA in combination with dexamethasone in newly diagnosed patients, but is not yet registered in the European Union. Its use is currently challenged by bortezomib and by thalidomide’s analog lenalidomide.

The role of the bone microenvironment in the pathophysiology and therapeutic management of multiple myeloma: interplay of growth factors, their receptors and stromal interactions

The close relationship between the biological behaviour of malignant cells and the local microenvironment where they reside is a feature of diverse neoplasias. Multiple myeloma (MM) is considered a main disease model for the study of such interactions and the mechanisms that can lead to bone-related clinical complications, as well as the role of these interactions in attenuating the activity of conventional anti-MM therapeutics, such as dexamethasone and cytotoxic chemotherapeutics. This review focuses on recent progress in the study of interactions of MM cells with their local microenvironment. Major emphasis is placed on how bone marrow stromal cells (BMSCs) and other normal constituents of the bone marrow milieu promote, through cell adhesion- and cytokine-mediated mechanisms, the ability of MM cells to resist conventional anti-MM therapies. The review also addresses ongoing research into these mechanisms, which has already provided several new molecular targets and corresponding therapeutic strategies, such as the proteasome inhibitor bortezomib and thalidomide derivatives (e.g. lenalidomide), for the management of myeloma.

Thalidomide and lenalidomide in the treatment of multiple myeloma

Although multiple myeloma (MM) is incurable with currently available treatments, the introduction of thalidomide and the development of safer and more active thalidomide analogues represent a major advance in the therapy of this disease. Thalidomide, initially introduced for treatment of MM because of its anti-angiogenic properties, has shown remarkable activity alone and in combination with other drugs in patients across all stages of the disease. Given the potential for teratogenicity with thalidomide and the non-haematologic toxicities of the drug, several analogues referred to as "immunomodulatory drugs" (IMiDs) were developed with the intent of enhancing the immunomodulatory effect while minimizing the teratogenic risk. Lenalidomide (CC-5013) and Actimid (CC-4047) are the first such analogues to undergo clinical testing. Lenalidomide has shown impressive activity in relapsed refractory myeloma as well as newly diagnosed disease. The precise mechanism of anti-MM activity of thalidomide and the IMiDs is not clear, but studies suggest that several other mechanisms besides anti-angiogenic effects may play a role. In this paper we review the development, pharmacology, mechanism of action, pre-clinical and clinical efficacy, and the current status of thalidomide and the IMiDs in the treatment of MM.

Novel biological therapies for the treatment of multiple myeloma

The therapeutic management of multiple myeloma (MM) for the last several decades has mainly involved regimens based on use of glucocorticoids and cytotoxic chemotherapeutics. Despite progress in delineating the activity of such regimens, at either conventional or high doses, MM has remained an incurable disease, without substantial improvement in the median overall survival. This has sparked major interest in the development of novel therapies that in part capitalize on recent advances in our understanding of the biology of MM, including the molecular mechanisms by which MM cell-host bone marrow (BM) interactions regulate tumor-cell growth, survival, and drug resistance in the BM milieu. The development of in vitro and in vivo models of MM-stromal interactions has allowed not only for better characterization of these molecular phenomena but also for identification of specific therapeutic strategies to overcome these interactions and achieve an enhanced anti-MM effect, even against MM resistant to conventional therapies. Herein, we review the latest progress in the development of these novel anti-MM therapies, with major focus on therapies which have translated from preclinical evaluation to clinical application, including thalidomide and its more potent immunomodulatory (IMiD) derivatives, the first-in-class proteasome inhibitor bortezomib (formerly known as PS-341), and arsenic trioxide (As2O3).

LASSBio-468: a new achiral thalidomide analogue which modulates TNF-alpha and NO production and inhibits endotoxic shock and arthritis in an animal model

As part of a program researching the synthesis and immunopharmacological evaluation of novel synthetic compounds, we have described the immune modulatory profile of the new achiral thalidomide analogue LASSBio-468 in the present work. This compound was planned as an N-substituted phthalimide derivate, structurally designed as a hybrid of thalidomide and aryl sulfonamides, which were previously described as tumor necrosis factor-alpha (TNF-alpha) and PDE4 inhibitors. LASSBio-468 was recently demonstrated to inhibit the TNF-alpha production induced by lipopolysaccharide (LPS), in vivo. Here, we investigated whether this compound would affect chronic inflammation processes associated with the production of this pro-inflammatory cytokine. Treatment with LASSBio-468 before a lethal dose injection of LPS in animals greatly inhibited endotoxic shock. This effect seems to be mediated by a specific down regulation of TNF-alpha and nitric oxide production, regulated mainly at the RNA level. In another model, histopathological analysis indicated that this compound also inhibited adjuvant-induced arthritis in rats. Taken together, our data demonstrated a potent anti-inflammatory effect of LASSBio-468, suggesting its use as a potential drug against chronic inflammatory diseases.

Adverse effects of thalidomide administration in patients with neoplastic diseases

Thalidomide, a glutamic acid derivative, was withdrawn from clinical use in 1962 due to its severe teratogenic effects. Its recent reinstitution in clinical practice was related to its benefits in leprosy and multiple myeloma. Moreover, the antiangiogenic and immunomodulatory properties of thalidomide have led to its evaluation in several malignant diseases, including myelofibrosis, renal cell cancer, prostate cancer, and Kaposi sarcoma. However, thalidomide use is associated with several side effects: somnolence and constipation are the most common, while deep vein thrombosis and peripheral neuropathy are the most serious. A combination of thalidomide with steroids or chemotherapy is being evaluated in several phase 2 studies. While it is not yet clear whether these combinations will enhance efficacy, they appear to increase the toxicity of thalidomide, and thalidomide analogs are being developed to minimize this toxicity. Ongoing studies will clarify the potential advantages of these agents in the treatment of neoplastic diseases.

Thalidomide: Current Role in the Treatment of Non-Plasma Cell Malignancies

Thalidomide, initially introduced as a sedative, was withdrawn from the market in the early 1960s after it was found to be a teratogen. However, it later found use as an investigational agent in the treatment of erythema nodosum leprosum, oral ulcers, graft versus host disease, and wasting associated with the human immunodeficiency syndrome. Its antiangiogenic properties were recognized in the early 1990s during a period where the importance of angiogenesis became increasingly apparent as a critical step in the in the proliferation and spread of malignant neoplasms. This led to the evaluation of thalidomide as an antiangiogenic agent in the treatment of several cancers. Thalidomide has already become part of standard therapy for the treatment of patients with relapsed and refractory multiple myeloma. It has also been found to have varying degree of benefit in various other malignancies. Although more clinical trials are needed, Kaposi's sarcoma and myelofibrosis represent other malignancies in which thalidomide has already demonstrated promising activity. The mechanism of action of thalidomide in cancer is still unclear, but do appear to be mediated by several other mechanisms in addition to its anti-angiogenic properties. This article reviews the current status of thalidomide for the treatment of non-plasma-cell malignancies.

Thalidomide and its derivatives: new promise for multiple myeloma

BACKGROUND

The combination of melphalan and prednisone has been accepted as standard treatment for multiple myeloma (MM) because most studies demonstrate only minimal survival benefit of combination chemotherapy regimens when compared with melphalan and prednisone. Despite modest gains with more intensive myeloablative regimens for certain subgroups, myeloma remains incurable. In 1999, investigators at the University of Arkansas reported the promising results of a phase II study of thalidomide in patients with resistant MM. Since then various trials of thalidomide alone, and in combination, have been tested in patients with resistant, and more recently, untreated MM. In addition, preliminary results of phase I studies of the immunomodulatory derivatives (IMiDs) of thalidomide have recently been reported.

METHODS

The author reviewed and reports the results of clinical trials of thalidomide and the IMiDs, as well as the pharmacology, mechanism of action, and toxicity of these agents.

RESULTS

Thalidomide has demonstrated significant activity in both resistant and previously untreated multiple myeloma. Combination therapy with dexamethasone increases response rate, even in patients previously resistant to both drugs given as single agents, indicating probable synergy. More recent studies of thalidomide-dexamethasone in previously untreated patients are encouraging. IMiD-3 is active in resistant myeloma and has a toxicity profile different from that of thalidomide.

CONCLUSIONS

Many studies have confirmed the activity of thalidomide in MM, as well as more responses with dexamethasone. Newer thalidomide derivatives with reduced toxicity are promising. Thalidomide-dexamethasone may now represent the treatment of choice for previously untreated patients. Further studies with these and other novel agents early in the course of myeloma, followed by rational programs of dose intensification, may improve complete remission rates and the frequency of long-term control.

Treatment of plasma cell dyscrasias with thalidomide and its derivatives

PURPOSE

In 1999, investigators reported promising results of a phase II study of thalidomide in patients with resistant multiple myeloma (MM). Since then, various trials of thalidomide alone and in combination with other agents have been tested in patients with resistant and, more recently, untreated MM. In addition, preliminary results of phase I studies of the immunomodulatory derivatives (IMiDs) of thalidomide have been recently reported.

DESIGN

We reviewed and report the results of clinical trials of thalidomide and the IMiDs, as well as the pharmacology, mechanism of action, and toxicity of these agents.

RESULTS

Thalidomide has demonstrated significant activity in both resistant and previously untreated multiple myeloma. Combination therapy with dexamethasone increases response rate, even in patients previously resistant to both drugs given as single agents. More recent studies of thalidomide with dexamethasone in previously untreated patients are highly encouraging. The addition of chemotherapy to thalidomide and dexamethasone may further increase response rates, but its effect on patient survival has not been clarified. Preliminary results of trials of IMiD-3 indicate that this agent is active in resistant myeloma and has a toxicity profile different from that of thalidomide.

CONCLUSION

Many studies have confirmed the activity of thalidomide in MM, as well as an improved response with dexamethasone. Newer thalidomide derivatives with reduced toxicity (neuropathy, teratogenicity) are also promising. Thalidomide with dexamethasone may now represent the treatment of choice for previously untreated patients. Further studies with these and other novel agents early in the course of myeloma may improve complete remission rates and frequency of long-term control.

Antiangiogenesis: the fifth cancer treatment modality?

PURPOSE/OBJECTIVES

To describe the biologic process of angiogenesis and the potential role of antiangiogenesis therapy in cancer treatment.

DATA SOURCES

Published articles, conference proceedings, and computerized databases.

DATA SYNTHESIS

Angiogenesis is the development of blood vessels. Antiangiogenic agents prevent the development of blood vessels, therefore preventing one mode of cancer metastasis. Clinical trials must be conducted to ascertain the most powerful antiangiogenic therapies. Trials combine chemotherapy, biotherapy, and radiotherapy with antiangiogenic therapy.

CONCLUSIONS

Information from animal studies has revealed that antiangiogenesis is a viable option in treating cancer and preventing metastasis. Although human studies are rare, preliminary results are promising, especially when antiangiogenesis is used in combination with current cancer treatment modalities.

IMPLICATIONS FOR NURSING

Nurses are in a unique position to teach patients about new treatments for cancer. Nurses must be knowledgeable about angiogenesis and the availability of potential antiangiogenesis agents. Nurses will be vital in collecting data in clinical trials, considering the subjective data that will be obtained.

Thalidomide: current therapeutic uses and management of its toxicities

Thalidomide currently is used to treat relapsed and refractory multiple myeloma. The drug also is being actively investigated in patients newly diagnosed with multiple myeloma. The therapeutic applications of thalidomide are expected to grow as clinical trials document its activity in treating other neoplastic disorders and diseases. Healthcare providers need to be well informed of its toxicities and able to identify their signs and symptoms immediately. They must have adequate knowledge about thalidomide administration and provide comprehensive patient education regarding thalidomide and its toxicities to ensure patient safety and compliance.

Thalidomide treatment in multiple myeloma

Thalidomide was first evaluated in patients with refractory multiple myeloma in the mid-90s. Based on the promising results achieved in these patients, the drug was subsequently used in earlier stages of the disease. Meanwhile, numerous phase II studies have been published using different doses and treatment schedules of thalidomide. In order to enhance efficacy, combinations of thalidomide with dexamethasone, chemotherapy and interferon were tried in different settings. In these trials important data regarding the toxicity profile of thalidomide have also been collected. Several trials in newly diagnosed myeloma patients are still ongoing. In the future, the optimal dose of thalidomide and the best schedule in combination with dexamethasone or chemotherapy have to be defined.Thalidomide's mechanism of action is still unclear. There are, however, several hypotheses regarding its mode of action. Recently, several analogues of thalidomide-the so-called ImiDs, have been developed. Preclinical data indicate that they might be more effective and less toxic than thalidomide. Trials evaluating the ImiDs in the clinical setting are still ongoing. In this paper, we will review the available clinical data regarding efficacy and toxicity of thalidomide, discuss its possible mechanism of action and point to future directions of research and clinical development of the ImiDs.

Response to thalidomide in chemotherapy-resistant mantle cell lymphoma: a case report

Mantle cell lymphoma is an aggressive B-cell lymphoma with a poor median survival despite conventional therapy. Here, we present the case of a patient with multiply relapsed mantle cell lymphoma, having failed treatment with chemotherapy, steroids and rituximab. He was treated with single-agent thalidomide at a dose of 800 mg daily and entered a good partial remission which was maintained for the next 6 months. There is clearly a need for further studies of thalidomide in mantle cell lymphoma to confirm this promising initial result.

Thalidomide in the treatment of myelodysplastic syndrome with fibrosis

A 67-year-old woman was admitted for investigation of pancytopenia. Bone marrow biopsy was compatible with myelodysplastic syndrome (MDS) with fibrosis. For the next 20 months the patient received transfusions of packed red cells, while a 3-month-trial of erythropoetin was unsuccesful. She was then treated with thalidomide 400mg per day. During the next months, a gradual rise in Hb value was noticed and the patient eventually became transfusion independent. Repeat bone marrow biopsy revealed a significant decrease on the degree of fibrosis. Thalidomide has shown excellent results in the treatment of multiple myeloma probably due to its anti-angiogenic activity. It is possible that in our patient thalidomide acted as an anti-fibrotic agent. It will be very interesting to test this novel activity of thalidomide in a large number of patients.

Thalidomide in the management of multiple myeloma

The discovery that multiple myeloma is associated with new vessel formation and is correlated with survival and proliferation led initially to the use of thalidomide for patients with relapsed or refractory disease. The outcome with conventional chemotherapy in this setting has historically been very poor. New insights into the biology of the disease suggests that thalidomide may work via a number of other mechanisms and the advent of the thalidomide analogues with their differential effects on survival and proliferation pathways has opened up a new era in the understanding and treatment of the disease. The encouraging results from phase I/II trials of these agents has meant that for the first time in 50 years there is the opportunity to improve outcome. Further work is in progress to define how best to use these drugs and their role in treatment at different stages of the disease.

Thalidomide for the treatment of relapsed and refractory multiple myeloma

Thalidomide is the first drug in over 20 years to demonstrate clinically significant activity in patients with multiple myeloma. Although the survival rate has not improved with conventional chemotherapy over the last 30 years, thalidomide has produced favorable responses in patients for whom most available therapies have failed, such as those whose disease was resistant or relapsed after standard and high-dose treatments. Despite the risk of adverse effects such as sedation and constipation, thalidomide has become an alternative therapy for patients with relapsed or refractory disease. New trials with thalidomide administered alone and in combination with other agents seem to show promise in patients with multiple myeloma, as do preliminary studies with thalidomide derivatives.

Thalidomide in multiple myeloma

Thalidomide--removed from widespread clinical use by 1962 because of severe teratogenicity--has anti-angiogenic and immunomodulatory effects, including the inhibition of TNF alpha. It has returned to practice as an effective oral agent in the management of various disease states including erythema nodosum leprosum, for which it was FDA-approved in 1998, and more recently certain malignancies, including multiple myeloma. Whilst the mechanism of action of thalidomide remains incompletely understood, considerable insight has been generated by extensive preclinical studies in multiple myeloma. Moreover, clinical trials both as a single agent and in combination have confirmed benefit in relapsed and refractory disease. Thalidomide's role in treating newly diagnosed patients is currently under study and it is now established as an important therapeutic option in the treatment of multiple myeloma.

Thalidomide: emerging role in cancer medicine

Thalidomide--removed from widespread clinical use by 1962 because of severe teratogenicity--has antiangiogenic and immunomodulatory effects, including the inhibition of tumor necrosis alpha factor. It has now returned to practice as an effective oral agent in the management of various disease states including erythema nodosum leprosum, for which it was approved by the U.S. Food and Drug Administration in 1998, and more recently certain malignancies, including multiple myeloma. Although thalidomide's mechanism of action remains incompletely understood, considerable insight has been generated by extensive preclinical studies in multiple myeloma. Moreover, clinical trials have confirmed benefit in relapsed disease, and the role of thalidomide in treating newly diagnosed patients is currently under study. Its use in other tumors is under evaluation, with promise in renal cell carcinoma, prostate cancer, glioma, and Kaposi's sarcoma. Activity has also been demonstrated in chronic graft-versus-host disease and in symptom relief as part of palliative care.

Thalidomide in multiple myeloma, myelodysplastic syndromes and histiocytosis. Analysis of clinical results and of surrogate angiogenesis markers

BACKGROUND

Thalidomide, as a single agent, has been recently found to induce a clinical response in one third of refractory or relapsed myeloma patients. Although it has been reported that thalidomide significantly inhibits angiogenesis. it is still unclear whether its clinical effect is mediated, at least in part, by its anti-angiogenic properties.

PATIENTS AND METHODS

We evaluated thalidomide as a single agent in myeloma, myelodysplastic syndromes (MDS) and histiocytosis, i.e. hematological diseases characterized by increased angiogenesis, and measured prospectively a number of surrogate angiogenesis markers.

RESULTS

Clinical responses were observed in 7 of 17 myeloma and 2 of 5 MDS patients. The histiocytosis patient had a partial response. At the time of the best clinical response, plasma levels of angiogenic growth factors, vascular endothelial growth factor (VEGF) and basic-fibroblast growth factor (b-FGF), were significantly decreased, and flow cytometry indicated a decrease of activated endothelial cells in the bone marrow of responding MDS patients.

CONCLUSIONS

These observations confirm thalidomide efficacy in myeloma, suggest a possible use in MDS and histiocytosis and may contribute to the prediction of clinical response and to understanding the mechanism of thalidomide's action.

Current role of thalidomide in cancer treatment

Thalidomide (Thalidomid, Celgene, Warren, NJ) is a putative anti-angiogenesis and immunomodulatory agent that has demonstrated activity in various dermatologic and rheumatologic conditions in addition to Crohn's disease. The biologic effects of thalidomide and the clinical trials conducted in solid tumors, hematologic malignancies, chronic graft-versus-host disease (GVHD), and cancer-related cachexia are reviewed. A summary of the preliminary results of ongoing clinical trials is presented, and the future directions of thalidomide research in the oncology are discussed.

A review of angiogenesis and antiangiogenic therapy with thalidomide in multiple myeloma

Angiogenesis is the formation of new blood vessels and occurs physiologically during embryonal growth, wound healing and during the menstrual cycle. It is essential for the proliferation and metastases of most malignant neoplasms. Recent evidence suggests that angiogenesis is increased in multiple myeloma and has prognostic value in the disease. Angiogenic cytokines such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor are expressed by myeloma cells and appear to play a role in the increased angiogenesis seen in myeloma. In addition, VEGF may serve as a paracrine growth factor for myeloma cells. Based on the increased angiogenesis observed in myeloma, thalidomide has been studied as antiangiogenic therapy. Although its mechanism of action in myeloma is still unclear, thalidomide appears to be active in 25-30% of patients with refractory myeloma. Major toxicities include constipation, sedation, skin rash, fatigue, and peripheral neuropathy. Studies are ongoing to determine its role as initial treatment for myeloma. This paper reviews the available data on angiogenesis in myeloma, and summarizes the role of thalidomide therapy in this disease. The pharmacology and toxicity of thalidomide are also discussed.