Filarial nematode phenotypic screening cascade to identify compounds with anti-parasitic activity for drug discovery optimization.

Filarial diseases, including lymphatic filariasis and onchocerciasis, are considered among the most devastating of all tropical diseases, affecting over 86 million people worldwide. To control and more rapidly eliminate onchocerciasis requires treatments that target the adult stage of the parasite. Drug discovery efforts are challenged by the lack of preclinical animal models using the human-pathogenic filariae, requiring the use of surrogate parasites for Onchocerca volvulus for both ex vivo and in vivo evaluation. Herein, we describe a platform utilizing phenotypic ex vivo assays consisting of the free-living nematode Caenorhabditis elegans, microfilariae and adult filariae of the bovine filariae Onchocerca lienalis and Onchocerca gutturosa, respectively, as well as microfilariae and adult filariae of the feline filariae Brugia pahangi, the rodent filariae Litomosoides sigmodontis and the human-pathogenic filariae Brugia malayi to assess activity across various surrogate parasites. Utilization of those surrogate nematodes for phenotypic ex vivo assays in order to assess activity across various parasites led to the successful establishment of a screening cascade and identification of multiple compounds with potential macrofilaricidal activity and desirable physicochemical, MW = 200-400 and low lipophilicity, logP <4, and pharmacokinetic properties, rat and human liver S9 stability of ≥70% remaining at 60 min, and AUC exposures above 3 µM h. This platform demonstrated the successful establishment of a screening cascade which resulted in the discovery of potential novel macrofilaricidal compounds for futher drug discovery lead optimization efforts. This screening cascade identified two distinct chemical series wherein one compound produced a significant 68% reduction of adult Litomosoides sigmodontis in the mouse model. Successful demonstration of efficacy prompted lead optimization medicinal chemistry efforts for this novel series.

AIM™ platform: A new immunotherapy approach for viral diseases.

In addition to complications of acute diseases, chronic viral infections are linked to both malignancies and autoimmune disorders. Lack of adequate treatment options for Epstein-Barr virus (EBV), Human T-lymphotropic virus type 1 (HTLV-1), and human papillomavirus (HPV) remains. The NexImmune Artificial Immune Modulation (AIM) nanoparticle platform can be used to direct T cell responses by mimicking the dendritic cell function. In one application, AIM nanoparticles are used ex vivo to enrich and expand (E+E) rare populations of multi-antigen-specific CD8+ T cells for use of these cells as an AIM adoptive cell therapy. This study has demonstrated using E+E CD8+ T cells, the functional relevance of targeting EBV, HTLV-1, and HPV. Expanded T cells consist primarily of effector memory, central memory, and self-renewing stem-like memory T cells directed at selected viral antigen peptides presented by the AIM nanoparticle. T cells expanded against either EBV- or HPV-antigens were highly polyfunctional and displayed substantial in vitro cytotoxic activity against cell lines expressing the respective antigens. Our initial work was in the context of exploring T cells expanded from healthy donors and restricted to human leukocyte antigen (HLA)-A*02:01 serotype. AIM Adoptive Cell Therapies (ACT) are also being developed for other HLA class I serotypes. AIM adoptive cell therapies of autologous or allogeneic T cells specific to antigens associated with acute myeloid leukemia and multiple myeloma are currently in the clinic. The utility and flexibility of the AIM nanoparticle platform will be expanded as we advance the second application, an AIM injectable off-the-shelf nanoparticle, which targets multiple antigen-specific T cell populations to either activate, tolerize, or destroy these targeted CD8+ T cells directly in vivo, leaving non-target cells alone. The AIM injectable platform offers the potential to develop new multi-antigen specific therapies for treating infectious diseases, cancer, and autoimmune diseases.

Discovery of a Stress-Activated Protein Kinase Inhibitor for Lymphatic Filariasis.

Lymphatic filariasis infects over 120 million people worldwide and can lead to significant disfigurement and disease. Resistance is emerging with current treatments, and these therapies have dose limiting adverse events; consequently new targets are needed. One approach to achieve this goal is inhibition of parasitic protein kinases involved in circumventing host defense mechanisms. This report describes structure-activity relationships leading to the identification of a potent, orally bioavailable stress activated protein kinase inhibitor that may be used to investigate this hypothesis.

Modernizing Clinical Trial Eligibility Criteria: Recommendations of the American Society of Clinical Oncology-Friends of Cancer Research HIV Working Group.

Purpose People with HIV are living longer as a result of effective antiretroviral therapy. Cancer has become a leading cause of morbidity and mortality in this patient population. However, studies of novel cancer therapeutics have historically excluded patients with HIV. Critical review of eligibility criteria related to HIV is required to accelerate development of and access to effective therapeutics for HIV-infected patients with cancer and make studies more generalizable to this patient population. Methods From January through April 2016, the HIV Working Group conducted a series of teleconferences; a review of 46 New Drug Applications from registration studies of unique agents studied in adults with cancer that led to the initial US Food and Drug Administration approval of that agent from 2011 to 2015; and a review of HIV-related eligibility criteria from National Cancer Institute-sponsored studies. Results were discussed and refined at a multistakeholder workshop held May 12, 2016. The HIV Working Group developed recommendations for eligibility criteria that focus on pharmacologic and immunologic considerations in this patient population and that balance patient safety, access to appropriate investigational agents, and study integrity. Results Exclusion of patients with HIV remains common in most studies of novel cancer agents. Models for HIV-related eligibility criteria in National Cancer Institute-sponsored studies are instructive. HIV infection itself should no longer be an exclusion criterion for most studies. Eligibility criteria related to HIV infection that address concurrent antiretroviral therapy and immune status should be designed in a manner that is appropriate for a given cancer. Conclusion Expanding clinical trial eligibility to be more inclusive of patients with HIV is justified in most cases and may accelerate the development of effective therapies in this area of unmet clinical need.

Restoration of immune surface molecules in Kaposi sarcoma-associated herpes virus infected cells by lenalidomide and pomalidomide.

Kaposi sarcoma-associated herpesvirus (KSHV) is the cause of several tumors, including Kaposi sarcoma and primary effusion lymphoma (PEL). Most viruses have evolved means of escaping immune recognition. KSHV downregulates MHC-I expression during lytic infection, and expression of ICAM-1 and B7-2 (CD86) during latent infection, allowing evasion of T cell and natural killer immunity respectively. These effects are largely mediated by two KSHV-encoded proteins, K3 and K5. We show here that lenalidomide (Len) and pomalidomide (Pom) prevent down-regulation of MHC-I during lytic activation, and restore ICAM-1 and B7-2 surface expression in latently infected PEL cells. Importantly, these changes occurred at clinically achievable concentrations and prior to any cytotoxic effects. Exploration of the mechanism revealed that Pom blocked lytic down-regulation of MHC-I induced by transfection with K3 but not K5. Although Pom alone did not significantly increase HLA mRNA expression in PEL cells, it did blunt the butyrate-induced decrease in MHC-I mRNA expression and decreased the upregulation of K3 mRNA in lytic cells. Virus-induced tumors express foreign antigens, but immunotherapy can be thwarted by viral strategies to evade immune recognition. The effects of Pom and Len described here can prevent these strategies and support the use of these drugs to treat KSHV-induced tumors.

Effectiveness of Risk Evaluation and Mitigation Strategies (REMS) for Lenalidomide and Thalidomide: Patient Comprehension and Knowledge Retention.

INTRODUCTION: The effectiveness of patient education activities conducted within the lenalidomide and thalidomide risk evaluation and mitigation strategies (REMS) programs was evaluated by measuring understanding of serious risk and safe-use messages. METHODS: Results from mandatory knowledge, attitude, and behavior surveys and voluntary patient surveys completed between June 2012 and June 2013 were analyzed, and responses to questions relating to compliance with birth control measures and understanding of safe-use messages are presented by patient risk category. RESULTS: In total, 73,645 patients were enrolled into the REMS programs for lenalidomide and thalidomide and completed mandatory surveys prior to medication dispense. Of these, 2790 (3.8%) completed an additional voluntary survey. Among voluntary survey participants, for all patient pregnancy risk categories, reported compliance with birth control requirements was above 90% when starting therapy and at follow-up. At the beginning of therapy, complete compliance was 96.3%; 3 months later it was 96.4%. Patient understanding of safe-use messages was very high in all pregnancy risk groups, notably for messages repeated at each physician visit. Overall, 98.2% of patients knew that lenalidomide and thalidomide could cause birth defects, which is part of the repeated educational messaging. In contrast, 87.1% recalled that unused product should be returned to their healthcare professional, which is not included in repeated messaging. CONCLUSION: The lenalidomide and thalidomide REMS programs enhance patient understanding of safe-use messages, resulting in high levels of compliance with the birth control precautions essential to prevent fetal exposure to these known and potential human teratogens. Overall compliance was maintained after 3 months of follow-up and throughout therapy.

Correlation of Antibody Responses to a Peptide Antigen gp120-C5501-512/gp41732-744 with HIV Disease Progression.

Antibodies to the carboxy-terminal constant (C5) region 5 of the HIV-1 envelope glycoprotein gp120 have previously been associated with slow disease progression. This is one of the regions on gp120 that interact with the transmembrane glycoprotein, gp41, anchoring it to the viral and infected cell membrane. This study analyzed humoral responses to a novel heterodimeric peptide construct comprising the C5501-512 region and a compatible region on gp41732-744. Antibody levels to C5501-512/gp41732-744 were associated with slow disease progression in a treatment naive historical longitudinal cohort from Norway (n = 32; p = .00001). Elevated anti-C5501-512/gp41732-744 antibody levels correlated with moderate viral load (VL) (50-10,000 copies/ml) in a cohort, including natural viral suppressors (NVS) in the Unites States (n = 58; p = .002). Analysis of HIV-positive sera from treatment naive patients in Estonia (n = 300) showed an inverse correlation between anti-C5501-512/gp41732-744 antibodies and VL when comparing VL 2,000-10,000 copies/ml with VL >10,000 (p = .050). Further mapping using peptide inhibition of antibody binding revealed that responses to the C5501-506 subdomain correlated with preserved CD4 counts (n = 55; p = .0012) irrespective of VL in this cohort. The C5 region encompassing C5501-506 shows sequence similarity to the shared epitope (SE) of certain HLA-DR associated with immune dysfunction. Partial antigenic cross-reactivity between SE and C5 is indicated by partial inhibition of NVS antibody binding using SE 15-mer peptide (median 65% inhibition), the C5501-506 6-mer peptide (79% inhibition), and binding of rheumatoid arthritis patient sera to both SE and C5 peptide sequences. The potential influence of these observations on HIV-1 pathogenesis remains to be determined.

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.

Pomalidomide for Symptomatic Kaposi's Sarcoma in People With and Without HIV Infection: A Phase I/II Study.

Purpose Kaposi's sarcoma (KS) is a multicentric tumor caused by Kaposi's sarcoma-associated herpesvirus. Unmet needs include therapies that are oral, anthracycline sparing, and deliverable in resource-limited settings. We evaluated pomalidomide, an oral immune modulatory agent, in patients with symptomatic KS. Methods The primary objectives were to assess tolerability, pharmacokinetics, and activity. Initial dosage level was 5 mg once per day for 21 days per 28-day cycle, with a de-escalated level of 3 mg if not tolerable, and aspirin 81 mg once per day thromboprophylaxis. HIV-infected patients required controlled viremia with either persistent KS despite 3 months of antiretroviral therapy (ART) or progressive KS despite 2 months of ART. Evaluations included tumor response and health-related quality of life (HRQL). Results Twenty-two patients were treated; 15 (68%) were HIV infected, 17 (77%) had advanced (T1) disease, and 19 (86%) previous KS therapy excluding ART. All were treated with 5 mg because no dose-limiting toxicities occurred. Over 156 cycles, the grade 3/4 adverse events possibly attributable to therapy were neutropenia (23 cycles, 10 patients), infection (1 cycle), and edema (1 cycle). Sixteen patients responded (73%; 95% CI, 50% to 89%): nine of 15 HIV-infected patients (60%; 95% CI, 32% to 84%) and all seven HIV-uninfected patients (100%; 95% CI, 59% to 100%). Median time to response was 4 weeks (range, 4 to 36 weeks). HRQL showed no impairment during therapy and improved satisfaction with appearance at end therapy ( P = .03). Significant increases in CD4+ and CD8+ cells were seen in patients with and without HIV, together with a transient increase in Kaposi's sarcoma-associated herpesvirus viral load at week 4 ( P = .05). Conclusion Pomalidomide is well tolerated and active in KS regardless of HIV status. Responses were rapid, with improved self-reported outcomes, and occurred in advanced and heavily pretreated disease. Correlative studies support, at least in part, an immunologic mechanism of activity.

Pharmacologic Inhibition of Host Phosphodiesterase-4 Improves Isoniazid-Mediated Clearance of Mycobacterium tuberculosis.

The lengthy duration of multidrug therapy needed to cure tuberculosis (TB) poses significant challenges for global control of the disease. Moreover, chronic inflammation associated with TB leads to pulmonary damage that can remain even after successful cure. Thus, there is a great need for the development of effective shorter drug regimens to improve clinical outcome and strengthen TB control. Host-directed therapy (HDT) is emerging as a novel adjunctive strategy to enhance the efficacy and shorten the duration of TB treatment. Previously, we showed that the administration of CC-3052, a phosphodiesterase-4 inhibitor (PDE4i), reduced the host inflammatory response during Mycobacterium tuberculosis (Mtb) infection and improved the antimicrobial efficacy of isoniazid (INH) in both the mouse and rabbit models. In the present study, we evaluated the pharmacokinetics and explored the mechanism underlying the efficacy of a more potent PDE4i, CC-11050, as adjunct to INH treatment in a mouse model of pulmonary Mtb infection. Genome-wide lung transcriptome analysis confirmed the dampening of inflammation and associated network genes that we previously reported with CC-3052. Consistent with the reduction in inflammation, a significant improvement in Mtb control and pathology was observed in the lungs of mice treated with CC-11050 plus INH, compared to INH alone. This important confirmatory study will be used to help design upcoming human clinical trials with CC-11050 as an HDT for TB treatment.

Adjunctive Phosphodiesterase-4 Inhibitor Therapy Improves Antibiotic Response to Pulmonary Tuberculosis in a Rabbit Model.

OBJECTIVES: Adjunctive host-directed therapy is emerging as a new potential approach to improve the outcome of conventional antimicrobial treatment for tuberculosis (TB). We tested the ability of a phosphodiesterase-4 inhibitor (PDE4i) CC-11050, co-administered with the first-line anti-TB drug isoniazid (INH), to accelerate bacillary killing and reduce chronic inflammation in the lungs of rabbits with experimental Mycobacterium tuberculosis (Mtb) infection. METHODS: A rabbit model of pulmonary TB that recapitulates the pathologic manifestations seen in humans was used. Rabbits were infected with virulent Mtb by aerosol exposure and treated for eight weeks with INH with or without CC-11050, starting at four weeks post infection. The effect of CC-11050 treatment on disease severity, pathology, bacillary load, T cell proliferation and global lung transcriptome profiles were analyzed. RESULTS: Significant improvement in bacillary clearance and reduced lung pathology and fibrosis were noted in the rabbits treated for eight weeks with INH + CC-11050, compared to those treated with INH or CC-11050 only. In addition, expression of host genes associated with tissue remodeling, tumor necrosis factor alpha (TNF-α) regulation, macrophage activation and lung inflammation networks was dampened in CC-11050-treated, compared to the untreated rabbits. CONCLUSIONS: Adjunctive CC-11050 therapy significantly improves the response of rabbits with experimental pulmonary TB to INH treatment. We propose that CC-11050 may be a promising candidate for host directed therapy of patients with pulmonary TB, reducing the duration and improving clinical outcome of antibiotic treatment.

A sensitive and robust HPLC assay with fluorescence detection for the quantification of pomalidomide in human plasma for pharmacokinetic analyses.

Pomalidomide is a second generation IMiD (immunomodulatory agent) that has recently been granted approval by the Food and Drug Administration for treatment of relapsed multiple myeloma after prior treatment with two antimyeloma agents, including lenalidomide and bortezomib. A simple and robust HPLC assay with fluorescence detection for pomalidomide over the range of 1-500ng/mL has been developed for application to pharmacokinetic studies in ongoing clinical trials in various other malignancies. A liquid-liquid extraction from human plasma alone or pre-stabilized with 0.1% HCl was performed, using propyl paraben as the internal standard. From plasma either pre-stabilized with 0.1% HCl or not, the assay was shown to be selective, sensitive, accurate, precise, and have minimal matrix effects (<20%). Pomalidomide was stable in plasma through 4 freeze-thaw cycles (<12% change), in plasma at room temperature for up to 2h for samples not pre-stabilized with 0.1% HCl and up to 8h in samples pre-stabilized with 0.1% HCl, 24h post-preparation at 4°C (<2% change), and showed excellent extraction recovery (∼90%). This is the first reported description of the freeze/thaw and plasma stability of pomalidomide in plasma either pre-stabilized with 0.1% HCl or not. The information presented in this manuscript is important when performing pharmacokinetic analyses. The method was used to analyze clinical pharmacokinetics samples obtained after a 5mg oral dose of pomalidomide. This relatively simple HPLC-FL assay allows a broader range of laboratories to measure pomalidomide for application to clinical pharmacokinetics.

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.

Lenalidomide in combination with rituximab for patients with relapsed or refractory mantle-cell lymphoma: a phase 1/2 clinical trial.

BACKGROUND: The combination of rituximab and lenalidomide has shown promise for the treatment of mantle-cell lymphoma (MCL) in preclinical studies. We aimed to identify the maximum tolerated dose (MTD) of lenalidomide when combined with rituximab in a phase 1 trial and to assess the efficacy and safety of this combination in a phase 2 trial in patients with relapsed or refractory MCL. METHODS: Patients with relapsed or refractory MCL who had received one to four previous lines of treatment were enrolled in this single-arm, open-label, phase 1/2 trial at MD Anderson Cancer Center. In phase 1, to identify the MTD of lenalidomide, four patient cohorts received escalating doses (10, 15, 20, and 25 mg) of daily oral lenalidomide on days 1-21 of each 28-day cycle. 375 mg/m(2) intravenous rituximab was also administered in four weekly doses during cycle 1 only. In phase 2, patients received rituximab plus the MTD of lenalidomide, following the same cycles as for phase 1. Treatment in both phases continued until disease progression, stem-cell transplantation, or severe toxicity. The primary efficacy endpoint was overall response (complete or partial response). The secondary efficacy endpoint was survival. We used the Kaplan-Meier method to estimate response duration, progression-free survival, and overall survival. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00294632. FINDINGS: 52 patients were enrolled between Feb 10, 2006 and July 30, 2009, 14 in phase 1 and 44 (including six patients who received the MTD of lenalidomide in the phase 1 portion) in phase 2. The MTD was 20 mg lenalidomide. One patient who was treated with 25 mg lenalidomide developed a grade 4 non-neutropenic infection and died. In the phase 2 portion of the study, grade 3-4 haematological toxicities included neutropenia (29 patients), lymphopenia (16 patients), leucopenia (13 patients), and thrombocytopenia (ten patients). There were only two episodes of febrile neutropenia. Among 44 patients in phase 2, 25 (57%) had an overall response: 16 (36%) had a complete response and nine (20%) had a partial response. The median response duration was 18·9 months (95% CI 17·0 months to not reached [NR]). The median progression-free survival was 11·1 months (95% CI 8·3 to 24·9 months), and the median overall survival was 24·3 months (19·8 months to NR). Five of 14 patients who had received bortezomib treatment before enrolment achieved an overall response. INTERPRETATION: Oral lenalidomide plus rituximab is well tolerated and effective for patients with relapsed or refractory MCL. FUNDING: Celgene.

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.

Tumor flare reaction associated with lenalidomide treatment in patients with chronic lymphocytic leukemia predicts clinical response.

BACKGROUND: In patients with chronic lymphocytic leukemia (CLL), treatment with lenalidomide induces a unique, previously uncharacterized, immune response called tumor flare reaction (TFR). The clinical significance of this reaction remains unknown. METHODS: Forty-five patients with CLL who were treated with lenalidomide in a phase 2 clinical trial were evaluated for the clinical features, intensity, and duration of TFR. Correlation was made with tumor response and the immune cellular microenvironment. Steroids for the prophylaxis of TFR was not given to patients in Group A (n = 29) whereas patients in Group B (n = 16) received low-dose prednisone as well as a slow dose escalation of lenalidomide for the prevention of TFR. RESULTS: Thirty (67%) patients experienced a TFR, with a grade 2 or 3 reaction (according to National Cancer Institute Common Toxicity Criteria [version 3.0]) observed in 33% of patients (47% in Group A and 9% in Group B; P = .05). The median time to onset of the TFR was 6 days, and was longer in the patients receiving prophylaxis (4 days vs 9 days, respectively; P = .01). A complete response was observed in 7 of 30 (23%) patients with TFR and 1 of 15 (7%) patients without TFR. The median progression-free survival was 19.9 months and 19.4 months, respectively, for patients with versus those without TFR (P = .92). CONCLUSIONS: TFR is a unique immune-mediated phenomenon noted with lenalidomide treatment only in patients with CLL that correlates with clinical response. It can be effectively managed with anti-inflammatory agents.

A review of the history, properties, and use of the immunomodulatory compound lenalidomide.

Lenalidomide (REVLIMID), an immunomodulatory compound targeting both cancer cells and their microenvironment, has substantial activity in several difficult-to-manage hematological malignancies. In previously treated multiple myeloma, lenalidomide produces high-quality responses combined with sustained disease control. Recently, several randomized studies have demonstrated a clinical benefit of continuous lenalidomide treatment in newly diagnosed multiple myeloma. In many patients with refractory anemia associated with lower risk myelodysplastic syndromes and a 5q chromosome deletion, lenalidomide leads to transfusion independence, considerably improving quality of life. It has a manageable safety profile, and its oral formulation reduces the burden on patients. Several phase III trials are ongoing in other indications currently underserved by conventional therapy, such as chronic lymphocytic leukemia, non-Hodgkin's lymphoma, and prostate cancer. Several early-stage studies are exploring lenalidomide alone and in combination across different hematological malignancies, solid tumors, and immune-related disorders.