A Phase II Randomized, Double-Blind, Placebo-Controlled Safety and Efficacy Study of Lenalidomide in Lumbar Radicular Pain with a Long-Term Open-Label Extension Phase.

Objective: This phase II study assessed lenalidomide efficacy and safety. Design: Three-phase core study: 14-day prerandomization, 12-week treatment, and 52-week open-label extension. Setting: Fourteen US centers from July 2005 to July 2007. Subjects: Chronic lumbar radicular pain patients without history of nerve injury or deficit. Methods: Subjects were randomized (1:1) to double-blind treatment with lenalidomide 10 mg or placebo once daily for 12 weeks, followed by a 52-week open-label extension. A 12-week, single-center, randomized-withdrawal (1:2, lenalidomide:placebo), exploratory study with open-label extension was undertaken in 12 subjects from the core extension who were naïve to neuropathic medications and with at least a two-point decrease from baseline average daily Pain Intensity-Numerical Rating Scale score. Results: Of 180 subjects enrolled, 176 had at least one postbaseline measure; 132 completed the 12-week treatment phase. In the core study, no statistically significant difference in Pain Intensity-Numerical Rating Scale mean change (-0.02, P = 0.958) was observed at week 12 between lenalidomide and placebo; proportions achieving pain reduction at week 12 and other secondary measures were comparable between lenalidomide and placebo. In the exploratory study, week 12 mean changes in Pain Intensity-Numerical Rating Scale scores were -0.05 (lenalidomide: N = 3) and 2.11 (placebo: N = 8). Mean changes in Brief Pain Inventory-short form interference scores were -3.33 and 8.38, respectively; scores at six months were maintained or decreased in 10 of 12 subjects. Conclusions: While this study does not support lenalidomide use in an unselected lumbar radicular pain population, an immunomodulating agent may relieve pain in select subjects naïve to neuropathic pain medications.ClinicalTrials.gov identifier: NCT00120120.

Mature results of MM-011: a phase I/II trial of liposomal doxorubicin, vincristine, dexamethasone, and lenalidomide combination therapy followed by lenalidomide maintenance for relapsed/refractory multiple myeloma.

A previous interim report of MM-011, the first study that combined lenalidomide with anthracycline-based chemotherapy followed by lenalidomide maintenance for relapsed and/or refractory multiple myeloma (RRMM), showed promising safety and activity. We report the long-term outcomes of all 76 treated patients with follow-up ≥ 5 years. This single-center phase I/II study administered lenalidomide (10 mg on days 1-21 of every 28-day cycle), intravenous liposomal doxorubicin (40 mg/m(2) on day 1), dexamethasone (40 mg on days 1-4), and intravenous vincristine (2 mg on day 1). After 4-6 planned induction cycles, lenalidomide maintenance therapy was given at the last tolerated dose until progression, with or without 50 mg prednisone every other day. The median number of previous therapies was 3 (range, 1-7); 49 (64.5%) patients had refractory disease. Forty-three (56.6%) patients received maintenance therapy. Grade 3/4 adverse events occurred during induction and maintenance therapy in 48.7% and 25.6% of patients, respectively. Four (5.3%) treatment-related deaths occurred during induction. Responses were seen in 53.0% (at least partial response) and 71.2% (at least minor response) of patients. Overall, median progression-free survival and overall survival were 10.5 and 19.0 months, respectively; in patients with refractory disease these values were 7.5 and 11.3 months, respectively. Lenalidomide with anthracycline-based chemotherapy followed by maintenance lenalidomide provided durable control in patients with RRMM (ClinicalTrials.gov number, NCT00091624).

Melphalan, lenalidomide and dexamethasone for the treatment of immunoglobulin light chain amyloidosis: results of a phase II trial.

We report results of a phase II trial of combination of melphalan, lenalidomide, and dexamethasone for the treatment of immunoglobulin light chain (AL) amyloidosis. The primary objectives were tolerability and hematologic response rate; secondary objectives were organ responses and survival. Treatment protocol consisted of melphalan 5 mg/m(2)/day for four days, lenalidomide 10 mg/day for 21 days and dexamethasone 20-40 mg once a week every 28 days for a total of 12 cycles. Sixteen subjects were enrolled of whom 14 completed at least 3 cycles and were evaluable for response. Grade 3/4 toxicities were experienced by 88% (n=14), the most common being myelosuppression (n=7). Dose reductions occurred in 85% (n=12 of 14) of subjects. Hematologic partial and complete responses were achieved by 43% (n=6 of 14) and 7% (n=1 of 14), respectively. The median overall survival has not been reached and median progression-free survival is 24 months. In conclusion, this combination is associated with significant myelosuppression leading to dose modifications and producing minor hematologic responses in AL amyloidosis. http://clinicaltrials.gov/ct2/show/NCT00679367.

Phosphodiesterase-4 inhibition combined with isoniazid treatment of rabbits with pulmonary tuberculosis reduces macrophage activation and lung pathology.

Tuberculosis (TB) is responsible for significant morbidity and mortality worldwide. Even after successful microbiological cure of TB, many patients are left with residual pulmonary damage that can lead to chronic respiratory impairment and greater risk of additional TB episodes due to reinfection with Mycobacterium tuberculosis. Elevated levels of the proinflammatory cytokine tumor necrosis factor-α and several other markers of inflammation, together with expression of matrix metalloproteinases, have been associated with increased risk of pulmonary fibrosis, tissue damage, and poor treatment outcomes in TB patients. In this study, we used a rabbit model of pulmonary TB to evaluate the impact of adjunctive immune modulation, using a phosphodiesterase-4 inhibitor that dampens the innate immune response, on the outcome of treatment with the antibiotic isoniazid. Our data show that cotreatment of M. tuberculosis infected rabbits with the phosphodiesterase-4 inhibitor CC-3052 plus isoniazid significantly reduced the extent of immune pathogenesis, compared with antibiotic alone, as determined by histologic analysis of infected tissues and the expression of genes involved in inflammation, fibrosis, and wound healing in the lungs. Combined treatment with an antibiotic and CC-3052 not only lessened disease but also improved bacterial clearance from the lungs. These findings support the potential for adjunctive immune modulation to improve the treatment of pulmonary TB and reduce the risk of chronic respiratory impairment.

Kidney dysfunction during lenalidomide treatment for AL amyloidosis.

BACKGROUND: Lenalidomide is an immunomodulatory agent used to treat plasma cell dyscrasias. We previously observed worsening of kidney function in a high proportion of patients with AL amyloidosis during lenalidomide treatment. The objective of this study is to characterize alterations in kidney function among patients with AL amyloidosis undergoing treatment with lenalidomide. METHODS: This is a secondary analysis of an ongoing clinical trial at a single referral centre. Forty-one patients with AL amyloidosis received lenalidomide with or without dexamethasone in monthly cycles. Kidney dysfunction was defined as ≥ 50% increase in serum creatinine. Severe kidney dysfunction was defined as ≥ 100% increase in serum creatinine. Recovery of renal function was defined as a return of serum creatinine to within 25% of the pre-treatment value or discontinuation of dialysis. RESULTS: Twenty-seven of 41 patients (66%) developed kidney dysfunction during lenalidomide treatment. The kidney dysfunction was severe in 13 of these patients (32%); four of whom required initiation of dialysis (10%). The median time to kidney dysfunction after starting lenalidomide was 44 days (interquartile range 15-108 days). Four of eight patients without underlying renal amyloidosis developed kidney dysfunction. Patients with severe kidney dysfunction were older and had a higher frequency of underlying renal amyloidosis, greater urinary protein excretion, and lower serum albumin. Recovery of renal function occurred in 12 patients (44%). CONCLUSIONS: Among patients with AL amyloidosis, worsening of kidney function occurs frequently during lenalidomide treatment. While a causal role of the drug has not been established, our findings suggest that kidney function should be monitored closely during treatment with this drug.

Lenalidomide plus dexamethasone for relapsed or refractory multiple myeloma.

BACKGROUND: Lenalidomide is a structural analogue of thalidomide with similar but more potent biologic activity. This phase 3, placebo-controlled trial investigated the efficacy of lenalidomide plus dexamethasone in the treatment of relapsed or refractory multiple myeloma. METHODS: Of 351 patients who had received at least one previous antimyeloma therapy, 176 were randomly assigned to receive 25 mg of oral lenalidomide and 175 to receive placebo on days 1 to 21 of a 28-day cycle. In addition, all patients received 40 mg of oral dexamethasone on days 1 to 4, 9 to 12, and 17 to 20 for the first four cycles and subsequently, after the fourth cycle, only on days 1 to 4. Patients continued in the study until the occurrence of disease progression or unacceptable toxic effects. The primary end point was time to progression. RESULTS: The time to progression was significantly longer in the patients who received lenalidomide plus dexamethasone (lenalidomide group) than in those who received placebo plus dexamethasone (placebo group) (median, 11.3 months vs. 4.7 months; P<0.001). A complete or partial response occurred in 106 patients in the lenalidomide group (60.2%) and in 42 patients in the placebo group (24.0%, P<0.001), with a complete response in 15.9% and 3.4% of patients, respectively (P<0.001). Overall survival was significantly improved in the lenalidomide group (hazard ratio for death, 0.66; P=0.03). Grade 3 or 4 adverse events that occurred in more than 10% of patients in the lenalidomide group were neutropenia (29.5%, vs. 2.3% in the placebo group), thrombocytopenia (11.4% vs. 5.7%), and venous thromboembolism (11.4% vs. 4.6%). CONCLUSIONS: Lenalidomide plus dexamethasone is more effective than high-dose dexamethasone alone in relapsed or refractory multiple myeloma. (ClinicalTrials.gov number, NCT00424047 [ClinicalTrials.gov].).

Lenalidomide plus dexamethasone for relapsed multiple myeloma in North America.

BACKGROUND: Lenalidomide, an oral immunomodulatory drug that is similar to thalidomide but has a different safety profile, has clinical activity in relapsed or refractory multiple myeloma. METHODS: Patients in the United States and Canada who had received at least one previous therapy for multiple myeloma but who required additional treatment were randomly assigned to receive either 25 mg of lenalidomide or placebo on days 1 to 21 of a 28-day cycle. Both groups also received 40 mg of oral dexamethasone on days 1 to 4, 9 to 12, and 17 to 20 for the first four cycles. After the fourth cycle, 40 mg of dexamethasone was administered only on days 1 to 4. Safety, clinical response, time to progression, and overall survival were assessed. RESULTS: We assigned 177 patients to the lenalidomide group and 176 to the placebo group. Complete, near-complete, or partial responses occurred in 108 patients (61.0%) in the lenalidomide group and in 35 patients (19.9%) in the placebo group (P<0.001); complete responses occurred in 14.1% and 0.6%, respectively (P<0.001). The median time to progression was 11.1 months in the lenalidomide group and 4.7 months in the placebo group (P<0.001). Median overall survival times in the two groups were 29.6 months and 20.2 months, respectively (P<0.001). Grade 3 or 4 adverse events were reported in 85.3% of the lenalidomide group and in 73.1% of the placebo group; these events resulted in study discontinuation in 19.8% and 10.2%, respectively. Grade 3 or 4 neutropenia and venous thromboembolism were more common in the lenalidomide group than in the placebo group (41.2% vs. 4.6% and 14.7% vs. 3.4%, respectively; P<0.001 for both comparisons). CONCLUSIONS: Lenalidomide plus dexamethasone is superior to placebo plus dexamethasone in patients with relapsed or refractory multiple myeloma. (ClinicalTrials.gov number, NCT00056160 [ClinicalTrials.gov].).

Lenalidomide plus dexamethasone is more effective than dexamethasone alone in patients with relapsed or refractory multiple myeloma regardless of prior thalidomide exposure.

This analysis assessed the efficacy and safety of lenalidomide + dexamethasone in patients with relapsed or refractory multiple myeloma (MM) previously treated with thalidomide. Of 704 patients, 39% were thalidomide exposed. Thalidomide-exposed patients had more prior lines of therapy and longer duration of myeloma than thalidomide-naive patients. Lenalidomide + dexamethasone led to higher overall response rate (ORR), longer time to progression (TTP), and progression-free survival (PFS) versus placebo + dexamethasone despite prior thalidomide exposure. Among lenalidomide + dexamethasone-treated patients, ORR was higher in thalidomide-naive versus thalidomide-exposed patients (P = .04), with longer median TTP (P = .04) and PFS (P = .02). Likewise for dexamethasone alone-treated patients (P = .03 for ORR, P = .03 for TTP, P = .06 for PFS). Prior thalidomide did not affect survival in lenalidomide + dexamethasone-treated patients (36.1 vs 33.3 months, P > .05). Thalidomide-naive and thalidomide-exposed patients had similar toxicities. Lenalidomide + dexamethasone resulted in higher rates of venous thromboembolism, myelosuppression, and infections versus placebo + dexamethasone, independent of prior thalidomide exposure. Lenalido-mide + dexamethasone was superior to placebo + dexamethasone, independent of prior thalidomide exposure. Although prior thalidomide may have contributed to inferior TTP and PFS compared with thalidomide-naive patients, these parameters remained superior compared with placebo + dexamethasone; similar benefits compared with placebo + dexamethasone were not evident for thalidomide-exposed patients in terms of overall survival. Studies were registered at http://www.clinicaltrials.gov under NCT00056160 and NCT00424047.

Seven-year median time to progression with thalidomide for smoldering myeloma: partial response identifies subset requiring earlier salvage therapy for symptomatic disease.

Smoldering multiple myeloma (SMM) is usually followed expectantly without therapy. We conducted a phase 2 trial in 76 eligible patients with SMM, combining thalidomide (THAL, 200 mg/d) with monthly pamidronate. In the first 2 years, THAL dose reduction was required in 86% and drug was discontinued in 50%. Within 4 years, 63% improved, including 25% qualifying for partial response (PR); by then, 34 patients had progressed and 17 required salvage therapy. Unexpectedly, attaining PR status was associated with a shorter time to salvage therapy for disease progression (P < .001), perhaps reflecting greater drug sensitivity of more aggressive disease. Low beta-2-microglobulin levels less than 2 mg/L were independently associated with superior overall and event-free survival. Four-year survival and event-free survival estimates of 91% and 60%, respectively, together with a median postsalvage therapy survival of more than 5 years justify the conduct of a prospective randomized clinical trial to determine the clinical value of preemptive therapy in SMM. Trial registered at http://www.clinicaltrials.gov under identifier NCT00083382.

Better quality of response to lenalidomide plus dexamethasone is associated with improved clinical outcomes in patients with relapsed or refractory multiple myeloma.

BACKGROUND: This retrospective pooled analysis of two phase III trials (MM-009/MM-010) compared clinical outcomes of patients who achieved a complete response or very good partial response to treatment with lenalidomide plus dexamethasone with the outcomes of those who only achieved a partial response. DESIGN AND METHODS: Patients (n=353) received lenalidomide (25 mg/day for 21 days of each 28-day cycle) plus dexamethasone (40 mg on days 1-4, 9-12, and 17-20 for four cycles, and only on days 1-4 after the first four cycles). Time to response, duration of response, time-to-progression, overall survival, and adverse events were investigated for patients who had a complete or very good partial response and compared with those of patients who had a partial response. RESULTS: At the time of unblinding, 32% of patients had achieved a complete or very good partial response and 28% had a partial response. Half (50.5%) of the patients who had a partial response as their initial response achieved a complete or very good partial response with further treatment. The probability of achieving a complete or very good partial response with continued lenalidomide treatment decreased with delayed achievement of a partial response (by cycle 4 versus later); however, it remained clinically significant. With an extended follow-up of 48 months, the median response duration, time-to-progression, and overall survival were longer in patients with a complete or very good partial response than in those with a partial response (24.0 versus 8.3 months, P<0.001; 27.7 versus 12.0 months, P<0.001; not reached versus 44.2 months, P=0.021, respectively). The benefit of a complete or very good partial response was independent of when it was achieved. CONCLUSIONS: Continuing treatment with lenalidomide plus dexamethasone to achieve best response, in the absence of disease progression and toxicity, provided deeper remissions and greater clinical benefit over time for patients in this study.

Lenalidomide oral monotherapy produces a high response rate in patients with relapsed or refractory mantle cell lymphoma.

Mantle cell lymphoma (MCL) is an aggressive non-Hodgkin lymphoma with a poor prognosis following first relapse. We present a subgroup analysis of an open-label phase II trial investigating the efficacy and safety of lenalidomide in patients with relapsed or refractory MCL. Oral lenalidomide 25 mg was self-administered once daily on days 1-21 every 28 d for up to 52 weeks, according to tolerability or until disease progression. The primary endpoint was overall response rate (ORR) and secondary endpoints were duration of response, progression-free survival (PFS) and safety. Among 15 patients with MCL with a median disease duration of 5.1 years and a median of four prior treatments, the ORR was 53%. Three patients (20%) had a complete response and 5 (33%) had a partial response. The median duration of response was 13.7 months and median PFS was 5.6 months. Four of five patients who relapsed after transplantation and two of five patients who previously received bortezomib responded to lenalidomide. The most common grade 4 adverse event was thrombocytopenia (13%) and the most common grade 3 adverse events were neutropenia (40%), leucopenia (27%) and thrombocytopenia (20%). In conclusion, oral lenalidomide monotherapy is well tolerated and active in relapsed or refractory MCL.

Expanded safety experience with lenalidomide plus dexamethasone in relapsed or refractory multiple myeloma.

Lenalidomide gained Food and Drug Administration (FDA) approval for treatment of patients with relapsed or refractory multiple myeloma (MM) in combination with dexamethasone in June 2006. In April 2005, the FDA and patient advocacy groups requested an expanded access programme to both provide lenalidomide to patients likely to benefit and obtain additional safety information. Relapsed/refractory MM patients received lenalidomide 25 mg/d (days 1-21) and dexamethasone 40 mg/d (days 1-4, 9-12, and 17-20 of cycles 1-4; days 1-4 only from cycle 5 onwards), in 4-week cycles until disease progression, study drug discontinuation, or lenalidomide approval. Of the 1438 patients enrolled, approximately 60% were male, median age was 64 years, and 61.7% had Durie-Salmon stage III disease. Median time on study was 15.4 weeks (range: 0.1-49.1) and median dose was 25 mg. The most common adverse events (AEs) were haematological (49%), gastrointestinal (59%), and fatigue (55%). The most common grade > or =3 AEs were haematological (45%), fatigue (10%), and pneumonia (7%). The most common serious AEs were pneumonia (8%), pyrexia (4%), and deep-vein thrombosis (3%). Primary cause of death was disease progression (10%). Safety data confirmed known AEs of lenalidomide plus dexamethasone therapy in patients with relapsed/refractory MM.

Lenalidomide in combination with dexamethasone at first relapse in comparison with its use as later salvage therapy in relapsed or refractory multiple myeloma.

This subset analysis of data from two phase III studies in patients with relapsed or refractory multiple myeloma (MM) evaluated the benefit of initiating lenalidomide plus dexamethasone at first relapse. Multivariate analysis showed that fewer prior therapies, along with beta(2)-microglobulin (< or = 2.5 mg/L), predicted a better time to progression (TTP; study end-point) with lenalidomide plus dexamethasone treatment. Patients with one prior therapy showed a significant improvement in benefit after first relapse compared with those who received two or more therapies. Patients with one prior therapy had significantly prolonged median TTP (17.1 vs. 10.6 months; P = 0.026) and progression-free survival (14.1 vs. 9.5 months, P = 0.047) compared with patients treated in later lines. Overall response rates were higher (66.9% vs. 56.8%, P = 0.06), and the complete response plus very good partial response rate was significantly higher in first relapse (39.8% vs. 27.7%, P = 0.025). Importantly, overall survival was significantly prolonged for patients treated with lenalidomide plus dexamethasone with one prior therapy, compared with patients treated later in salvage (median of 42.0 vs. 35.8 months, P = 0.041), with no differences in toxicity, dose reductions, or discontinuations despite longer treatment. Therefore, lenalidomide plus dexamethasone is both effective and tolerable for second-line MM therapy and the data suggest that the greatest benefit occurs with earlier use.

Melphalan, prednisone, and lenalidomide for newly diagnosed myeloma: kinetics of neutropenia and thrombocytopenia and time-to-event results.

BACKGROUND: Initial analysis of the combination melphalan, prednisone, plus lenalidomide (MPR) showed significant antimyeloma activity in patients with untreated multiple myeloma, with neutropenia and thrombocytopenia as the most frequent side effects. This updated analysis reassessed the kinetics of neutropenia and thrombocytopenia as well as the safety and efficacy of MPR. PATIENTS AND METHODS: A total of 21 patients with newly diagnosed myeloma received melphalan 0.18 mg/kg on days 1-4, prednisone 2 mg/kg on days 1-4, and lenalidomide 10 mg daily on days 1-21 for nine 28-day cycles, followed by maintenance therapy with lenalidomide 10 mg daily on days 1-21. RESULTS: Grade 3/4 neutropenia occurred in 52% of the patients, and granulocyte colonystimulating factor was administered in 43%. The mean neutrophil counts at the start of each MPR cycle, during nadir, and after 6 months of maintenance were 2.69 x 109/L, 1.43 x 109/L, and 2.11 x 109/L, respectively. Grade 3/4 thrombocytopenia occurred in 24% of the patients. Platelet transfusions were required by 1 patient (5%) with a platelet count of 16 x 109/L; however, no thrombocytopenia-associated bleeding was reported. The mean platelet counts at the start of each cycle, during nadir, and after 6 months of maintenance were 174 x 109/L, 121 x 109/L, and 158 x 109/L, respectively. Median follow-up was 29.6 months, median progression-free survival was 28.5 months, and 2-year overall survival was 91%. CONCLUSION: MPR is a promising regimen with manageable hematologic toxicity.

Venous thromboembolism in myelodysplastic syndrome patients receiving lenalidomide: results from postmarketing surveillance and data mining techniques.

BACKGROUND AND OBJECTIVES: Multiple myeloma treatment with lenalidomide-based regimens is associated with risk of venous thromboembolism (VTE), particularly during concomitant use with erythropoiesis-stimulating agents (ESAs). The risk of VTE in myelodysplastic syndrome (MDS) patients treated with lenalidomide is not well characterized and the background risk in untreated patients is not known. This study set out to determine the reporting rate of VTE in MDS patients on lenalidomide in the two years of postmarketing experience in the US, and to investigate whether there is a disproportional signal of VTE in MDS patients on lenalidomide by screening the US FDA Adverse Event Reporting System (AERS) safety database. METHODS: The MDS population exposed to lenalidomide was obtained from RevAssist, the company's proprietary restrictive distribution programme. VTE reports were identified from the company's postmarketing surveillance safety database. The FDA AERS database was used for disproportionality analysis, and signal scores computed using three algorithms: multi-item gamma Poisson shrinker (MGPS), proportional reporting ratio (PRR), and reporting odds ratios (ROR). RESULTS: A total of 7764 MDS patients were prescribed lenalidomide during the first two years of commercial use in the US. VTE representing deep vein thrombosis and pulmonary embolism was reported in 41 patients, a reporting rate of 0.53%. The computed signal scores did not exceed the statistical threshold for identification of a significant disproportional signal for VTE in MDS reports involving use of lenalidomide without concomitant use of ESAs. However, a disproportional signal of VTE was detected in MDS reports where lenalidomide was concurrently used with ESAs. CONCLUSION: The VTE reporting rate for MDS patients receiving lenalidomide during the first two years of postmarketing exposure was low (0.53%). Disproportionality analysis demonstrated a statistically meaningful association of VTE with lenalidomide concomitantly used with ESAs in MDS patients, but the association was not statistically significant when lenalidomide was used in the absence of ESAs.

Alternate day pomalidomide retains anti-myeloma effect with reduced adverse events and evidence of in vivo immunomodulation.

We previously reported that daily dose pomalidomide (CC-4047), a thalidomide analogue, has excellent anti-myeloma activity but is associated with myelosuppression and deep vein thrombosis. We report here a phase 1 study to determine the maximum tolerated dose (MTD) of pomalidomide at 1 mg, 2 mg, 5 mg and 10 mg on alternate days (ad). Twenty patients with relapsed myeloma were treated. Grade 4 neutropenia occurred in all patients receiving 10 mg and the MTD was defined as 5 mg ad. No thrombotic events were observed. Pomalidomide was continued following the 4-week MTD study in 17/20 patients for a median of 14 months. 10% of patients had a complete response and >50% reduction in paraprotein was achieved in 50% of subjects. Progression-free survival was 10.5 months and median overall survival was 33 months. A significant rise was observed in the proportion of CD8(+) cells. Alternate day pomalidomide was associated with a marked reduction in the incidence of thrombosis whilst maintaining excellent anti-myeloma activity. This trial provides further in vivo evidence that pomalidomide modulates the immune system in myeloma patients. Phase 2 studies to further assess the optimal schedule of administration and anti-myeloma activity of this agent are planned.

Efficacy of lenalidomide in myelodysplastic syndromes.

BACKGROUND: Ineffective erythropoiesis is the hallmark of myelodysplastic syndromes. Management of the anemia caused by ineffective erythropoiesis is difficult. In patients with myelodysplastic syndromes and symptomatic anemia, we evaluated the safety and hematologic activity of lenalidomide, a novel analogue of thalidomide. METHODS: Forty-three patients with transfusion-dependent or symptomatic anemia received lenalidomide at doses of 25 or 10 mg per day or of 10 mg per day for 21 days of every 28-day cycle. All patients either had had no response to recombinant erythropoietin or had a high endogenous erythropoietin level with a low probability of benefit from such therapy. The response to treatment was assessed after 16 weeks. RESULTS: Neutropenia and thrombocytopenia, the most common adverse events, with respective frequencies of 65 percent and 74 percent, necessitated the interruption of treatment or a dose reduction in 25 patients (58 percent). Other adverse events were mild and infrequent. Twenty-four patients had a response (56 percent): 20 had sustained independence from transfusion, 1 had an increase in the hemoglobin level of more than 2 g per deciliter, and 3 had more than a 50 percent reduction in the need for transfusions. The response rate was highest among patients with a clonal interstitial deletion involving chromosome 5q31.1 (83 percent, as compared with 57 percent among those with a normal karyotype and 12 percent among those with other karyotypic abnormalities; P=0.007) and patients with lower prognostic risk. Of 20 patients with karyotypic abnormalities, 11 had at least a 50 percent reduction in abnormal cells in metaphase, including 10 (50 percent) with a complete cytogenetic remission. After a median follow-up of 81 weeks, the median duration of transfusion independence had not been reached and the median hemoglobin level was 13.2 g per deciliter (range, 11.5 to 15.8). CONCLUSIONS: Lenalidomide has hematologic activity in patients with low-risk myelodysplastic syndromes who have no response to erythropoietin or who are unlikely to benefit from conventional therapy.

RevAssist: a comprehensive risk minimization programme for preventing fetal exposure to lenalidomide.

Lenalidomide (Revlimid) is an immunomodulatory drug and an analogue of thalidomide, a known teratogen. To prevent fetal exposure, in the US lenalidomide is available only under a special restricted distribution programme called RevAssist. Under this risk minimization programme, only prescribers and contract pharmacies registered with the programme are able to prescribe and dispense the product. Patients must be advised of, agree to and comply with the requirements of the RevAssist programme in order to receive lenalidomide through a registered prescriber. A total of 15 584 patients were registered in the RevAssist programme during the first year lenalidomide was on the market. There were four reports of false-positive beta-human chorionic gonadotrophin measurements in patients aged 43-57 years. Mandatory patient and prescriber surveys have shown discrepant responses that were resolved by risk management intervention specialists 99% of the time. The voluntary patient surveys have shown understanding of the risks of lenalidomide use and of behaviours necessary to minimize risks in >95% of females of childbearing potential and adult males. To date, there have been no reports of pregnancy in female patients or female partners of male patients. The pharmacy audit findings showed compliance with RevAssist was high. Although RevAssist is labour-intensive, time-consuming and costly, it continues to be effective in preventing fetal exposure to lenalidomide.