Temsirolimus in the treatment of mantle cell lymphoma: frequency and management of adverse effects

Determination of five mTOR inhibitors in human plasma for hepatocellular carcinoma treatment using QuEChERS-UHPLC-MS/MS

A fast and reliable QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method for pre-processing combined with Ultra - high performance liquid chromatography - tandem mass spectrometry (UHPLC-MS/MS) was established for the analysis of five mammalian rapamycin target protein (mTOR) inhibitors (vistusertib, AZD8055, pictilisib, everolimus, temsirolimus)in human plasma. Extraction was achieved by addition of acetonitrile to the sample followed by anhydrous magnesium sulfate and 30 mg C18 for salting out and purification, respectively. MTOR inhibitors were detected using selective response monitoring (SRM) under positive ion electrospray mode. Vistusertib, AZD8055 and pictilisib showed good linearity with a range of 1-80 ng/ml, Additionally, the concentration of everolimus and temsirolimus was 2.5-200 ng/ml and10-800 ng/ml, respectively. The linear correlation coefficient (R2) of each analysis was ≥ 0.9950. The limit of detection (LOD) and Limit of Quantitation (LOQ) were 0.015-0.75 ng/ml and 1-10 ng/ml, respectively. This method showed a high accuracy with high recovery rate and excellent stability. This method is fast, accurate and reliable, suitable for quantitative detection of mTOR inhibitors in human plasma.

Waldenström Macroglobulinemia: Mechanisms of Disease Progression and Current Therapies

Waldenström macroglobulinemia is an indolent, B-cell lymphoma without a known cure. The bone marrow microenvironment and cytokines both play key roles in Waldenström macroglobulinemia (WM) tumor progression. Only one FDA-approved drug exists for the treatment of WM, Ibrutinib, but treatment plans involve a variety of drugs and inhibitors. This review explores avenues of tumor progression and targeted drug therapy that have been investigated in WM and related B-cell lymphomas.

Management of Drug Resistance in Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is a rare but aggressive B-cell hemopathy characterized by the translocation t(11;14)(q13;q32) that leads to the overexpression of the cell cycle regulatory protein cyclin D1. This translocation is the initial event of the lymphomagenesis, but tumor cells can acquire additional alterations allowing the progression of the disease with a more aggressive phenotype and a tight dependency on microenvironment signaling. To date, the chemotherapeutic-based standard care is largely inefficient and despite the recent advent of different targeted therapies including proteasome inhibitors, immunomodulatory drugs, tyrosine kinase inhibitors, relapses are frequent and are generally related to a dismal prognosis. As a result, MCL remains an incurable disease. In this review, we will present the molecular mechanisms of drug resistance learned from both preclinical and clinical experiences in MCL, detailing the main tumor intrinsic processes and signaling pathways associated to therapeutic drug escape. We will also discuss the possibility to counteract the acquisition of drug refractoriness through the design of more efficient strategies, with an emphasis on the most recent combination approaches.

Prospective Study of Drug-induced Interstitial Lung Disease in Advanced Breast Cancer Patients Receiving Everolimus Plus Exemestane

BACKGROUND

Everolimus-related interstitial lung disease (ILD) (also: pneumonitis) poses a difficulty for physicians, as it is hard to discriminate ILD from other causes of respiratory symptoms and to decide on safe treatment continuation.

OBJECTIVE

We investigated the capability of pulmonary function tests (PFT), plasma biomarkers, everolimus pharmacokinetics, and FDG-PET to discriminate between everolimus-related ILD and other causes of respiratory problems and to predict the severity of ILD.

PATIENTS AND METHODS

Women starting treatment with everolimus plus exemestane for advanced breast cancer were included. At baseline and during the first 3 months, respiratory symptoms, PFT with diffusion capacity of the lungs for carbon monoxide corrected for hemoglobin (DLCOc) and forced vital capacity, serum plasma biomarkers (including SP-D and YKL-40), everolimus trough concentration, and 18F-FDG-PET were prospectively recorded.

RESULTS

Twenty-seven (out of 29 included) patients were evaluable for analysis. Fifteen patients (56%) developed everolimus-related respiratory signs or symptoms and four patients (15%) needed everolimus discontinuation and received corticosteroids. Change in DLCOc differentiated ILD from alternative diagnoses with 0.91 sensitivity and 0.78 specificity. Decrease in DLCOc (non-significant) was greatest in patients who needed everolimus discontinuation. Serum SP-D and YKL-40 could differentiate ILD from alternative diagnoses with 0.83 and 0.83 sensitivity, and 0.85 and 0.62 specificity, respectively. 18F-FDG-PET abnormalities did not precede clinical symptoms. No relationship between ILD and everolimus trough concentration was found.

CONCLUSIONS

This study shows that everolimus-related ILD occurs frequently. Prospective monitoring of DLCOc in combination with measurement of serum SP-D and YKL-40 appear useful to discriminate ILD from other causes of respiratory symptoms. Clinicaltrials.gov identifier: NCT01978171.

Everolimus for the treatment of advanced gastrointestinal or lung nonfunctional neuroendocrine tumors in East Asian patients: a subgroup analysis of the RADIANT-4 study

Background

In RADIANT-4, everolimus showed an improvement of 7.1 months in median progression-free survival (PFS) vs placebo among patients with advanced, well-differentiated, nonfunctional neuroendocrine tumors (NETs) of gastrointestinal (GI) or lung origin. The present analysis focuses on the effect of everolimus on the East Asian-subgroup population of the RADIANT-4 study.

Methods

Patients were randomized to receive everolimus 10 mg/day or matching placebo. The primary end point was PFS (central review). Secondary end points were overall response rate, safety, and tolerability.

Results

Among 302 patients enrolled in RADIANT-4, 46 were included in the East Asian subgroup (everolimus, n=28; placebo, n=18) analysis. Everolimus was associated with an 82% reduction in the relative risk of disease progression or death (HR 0.18, 95% CI 0.09–0.38). The median PFS (central review) in this subgroup was 11.2 months with everolimus vs 3.1 months with placebo. Adverse events (AEs) occurred in all 28 patients treated with everolimus and ten patients receiving placebo. The majority of these AEs were grade 1 or 2. Most commonly reported ($30% of incidence) drug-related AEs of any grade included stomatitis (75%, n=21) and rash (43%, n=12) in the everolimus arm.

Conclusion

Everolimus demonstrated a clinically meaningful PFS benefit in the East Asian population. The safety findings were consistent with the known safety profile of everolimus. These results support the use of everolimus in the East Asian population with advanced, nonfunctional NETs of GI or lung origin.

Risk of mTOR inhibitors induced severe pneumonitis in cancer patients: a meta-analysis of randomized controlled trials

Background: A meta-analysis of randomized controlled trials was performed to determine the overall risk of noninfectious severe pneumonitis associated with mTOR inhibitors (mTORi) in cancer patients. Materials & methods: PubMed, EMBASE and oncology conference proceedings were searched for relevant studies. Results: A total of 8377 patients from 16 randomized controlled trials were included. The incidence of severe pneumonitis associated with mTORi was 1.7% (95% CI: 1.1–2.5%). The use of mTORi significantly increased the risk of severe pneumonitis compared with controls (odds ratio: 3.36; 95% CI: 2.20–5.12). The analysis was stratified for drug types, tumor types, controlled therapy and mTORi-based regimens, but no significant differences in odds ratios were observed. Conclusion: mTORi significantly increase the risk of severe pneumonitis in cancer patients.

Drug-related pneumonitis during mammalian target of rapamycin inhibitor therapy in patients with neuroendocrine tumors: a radiographic pattern-based approach

PURPOSE

The purpose of this study was to investigate the incidence of drug-related pneumonitis during mammalian target of rapamycin (mTOR) inhibitor therapy in patients with neuroendocrine tumours (NET) and characterise radiographic patterns of pneumonitis.

METHODS

Sixty-six patients (39 males, 27 females, age: 22-79 years) with advanced NET treated with mTOR inhibitor, everolimus, were retrospectively studied. Chest computed tomography scans during therapy were reviewed for abnormalities suspicious for drug-related pneumonitis by an independent review of two radiologists. Extent, distributions, and specific findings were evaluated in cases positive for pneumonitis. Radiographic patterns of pneumonitis were classified using the American Thoracic Society/European Respiratory Society classification of interstitial pneumonia.

RESULTS

Drug-related pneumonitis was radiographically detected in 14 patients (21%). Time from the initiation of therapy to pneumonitis was within 6 months of therapy in 10 patients (71%), while it ranged from 1.0 to 27.7 months. Pneumonitis was more common in patients who had never smoked (p=0.03). Lower lungs were more extensively involved than upper and middle lungs. Peripheral and lower distributions were most common (n=8), followed by peripheral and multifocal distributions (n=3). Ground glass and reticular opacities were present in all cases, with consolidation in eight cases. The radiographic pattern of pneumonitis was classified as cryptogenic organising pneumonia (COP) pattern in eight patients, non-specific interstitial pneumonia (NSIP) pattern in five, and hypersensitivity pneumonitis pattern in one patient.

CONCLUSION

Drug-related pneumonitis was noted in 21% of the advanced NET patients treated with everolimus. Radiographic pattern of pneumonitis was most commonly COP pattern, followed by NSIP pattern.

Combination Therapy Targeting Ribosome Biogenesis and mRNA Translation Synergistically Extends Survival in MYC-Driven Lymphoma

Ribosome biogenesis and protein synthesis are dysregulated in many cancers, with those driven by the proto-oncogene c-MYC characterized by elevated Pol I-mediated ribosomal rDNA transcription and mTORC1/eIF4E-driven mRNA translation. Here, we demonstrate that coordinated targeting of rDNA transcription and PI3K-AKT-mTORC1-dependent ribosome biogenesis and protein synthesis provides a remarkable improvement in survival in MYC-driven B lymphoma. Combining an inhibitor of rDNA transcription (CX-5461) with the mTORC1 inhibitor everolimus more than doubled survival of Eμ-Myc lymphoma-bearing mice. The ability of each agent to trigger tumor cell death via independent pathways was central to their synergistic efficacy. CX-5461 induced nucleolar stress and p53 pathway activation, whereas everolimus induced expression of the proapoptotic protein BMF that was independent of p53 and reduced expression of RPL11 and RPL5. Thus, targeting the network controlling the synthesis and function of ribosomes at multiple points provides a potential new strategy to treat MYC-driven malignancies.

SIGNIFICANCE

Treatment options for the high proportion of cancers driven by MYC are limited. We demonstrate that combining pharmacologic targeting of ribosome biogenesis and mTORC1-dependent translation provides a remarkable therapeutic benefit to Eμ-Myc lymphoma-bearing mice. These results establish a rationale for targeting ribosome biogenesis and function to treat MYC-driven cancer.

Drug-Related Pneumonitis During Mammalian Target of Rapamycin Inhibitor Therapy: Radiographic Pattern-Based Approach in Waldenström Macroglobulinemia as a Paradigm

BACKGROUND

This study determined the frequency of drug-related pneumonitis during mammalian target of rapamycin (mTOR) inhibitor therapy in Waldenström macroglobulinemia patients and investigated the imaging characteristics and radiographic patterns of pneumonitis.

MATERIALS AND METHODS

A total of 40 patients (23 men, 17 women; 43-84 years old) with Waldenström macroglobulinemia treated in 2 trials of the mTOR inhibitor everolimus were retrospectively studied. Chest computed tomography (CT) scans during therapy were reviewed for abnormalities suspicious for drug-related pneumonitis by the consensus of three radiologists, evaluating the extent, distributions, and specific findings. The radiographic patterns of pneumonitis were classified using the American Thoracic Society/European Respiratory Society classification of interstitial pneumonia.

RESULTS

Drug-related pneumonitis was noted in 23 patients (58%). The median time from the initiation of therapy to the onset of pneumonitis was 5.7 months. Lower lungs were involved in all 23 patients, with a higher extent than in the other zones (p < .001). The distribution was peripheral and lower in 11 patients (48%) and mixed and multifocal in 10 (44%). The findings were bilateral in 20 patients (87%). Ground glass opacities (GGOs) and reticular opacities were present in all 23 patients, with consolidation in 12, traction bronchiectasis in 2, and centrilobular nodularity in 1. The pattern of pneumonitis was classified as cryptogenic organizing pneumonia (COP) in 16 (70%) and nonspecific interstitial pneumonia (NSIP) in 7 (30%), with overlapping features of COP and NSIP in 7 patients.

CONCLUSION

Drug-related pneumonitis was noted on CT in 58% of Waldenström macroglobulinemia patients treated with mTOR inhibitor therapy. Most common findings were bilateral GGOs and reticular opacities, with or without consolidation, in peripheral and lower lungs, demonstrating COP and NSIP patterns.

IMPLICATIONS FOR PRACTICE

The present study has demonstrated that drug-related pneumonitis during mammalian target of rapamycin (mTOR) inhibitor therapy is highly frequent, occurring in 58% of patients with Waldenström macroglobulinemia. The radiographic patterns of pneumonitis demonstrated cryptogenic organizing pneumonia and nonspecific interstitial pneumonia patterns, with overlapping features in 30% of the patients. The present study describes an initial attempt of a radiographic pattern-based approach to drug-related pneumonitis in the era of molecular targeting therapy, with a cohort of patients with Waldenström macroglobulinemia receiving mTOR inhibitor therapy as a paradigm, which might contribute to further understanding and in-depth interpretation of lung toxicity during novel cancer therapy.

Phase 1b study of otlertuzumab (TRU-016), an anti-CD37 monospecific ADAPTIR™ therapeutic protein, in combination with rituximab and bendamustine in relapsed indolent lymphoma patients

PURPOSE

CD37 is cell surface tetraspanin present on normal and malignant B cells. Otlertuzumab (TRU-016) is a novel humanized anti-CD37 protein therapeutic that triggers direct caspase independent apoptosis of malignant B cells and induces antibody-dependent cell-mediated cytotoxicity. This study evaluated the safety, pharmacokinetics, and efficacy of otlertuzumab administered in combination with rituximab and bendamustine to patients with relapsed, indolent B-cell non-Hodgkin Lymphoma (NHL).

METHODS

Patients with relapsed or refractory NHL received otlertuzumab (10 or 20 mg/kg) intravenously (IV) on days 1 and 15, bendamustine (90 mg/m(2)) on days 1 and 2, and rituximab (375 mg/m(2)) on day 1 for up to six 28 day cycles. Responses were determined using standard criteria.

RESULTS

Twelve patients were treated with 6 patients at each dose level; median age was 57 years (range, 51-79), and median number of prior regimens was 3 (range, 1-4). All patients had relapsed after prior rituximab including 7 refractory to their most recent previous treatment. In the 10 and 20 mg/kg dose cohorts, the mean half-life was 8 and 10 days following the first dose, and 12 or 14 days following 12 doses of otlertuzumab, respectively. Overall response rate was 83% (10/12) with 4 CRs (32%). The most frequent adverse events were neutropenia, nausea, fatigue, leukopenia, and insomnia; most were grade 1 or 2.

CONCLUSIONS

Otlertuzumab in combination with rituximab and bendamustine was well tolerated and induced responses in the majority of patients with relapsed indolent B-NHL. NCI Clinical Trials Network registration: NCT01317901.

Picking the point of inhibition: a comparative review of PI3K/AKT/mTOR pathway inhibitors

The frequent activation of the PI3K/AKT/mTOR pathway in cancer, and its crucial role in cell growth and survival, has made it a much desired target for pharmacologic intervention. Following the regulatory approval of the rapamycin analogs everolimus and temsirolimus, recent years have seen an explosion in the number of phosphoinositide 3-kinase (PI3K) pathway inhibitors under clinical investigation. These include: ATP-competitive, dual inhibitors of class I PI3K and mTORC1/2; "pan-PI3K" inhibitors, which inhibit all four isoforms of class I PI3K (α, β, δ, γ); isoform-specific inhibitors of the various PI3K isoforms; allosteric and catalytic inhibitors of AKT; and ATP-competitive inhibitors of mTOR only (and thus mTORC1 and mTORC2). With so many agents in development, clinicians are currently faced with a wide array of clinical trials investigating a multitude of inhibitors with different mechanisms of action, being used both as single agents and in combination with other therapies. Here, we provide a review of the literature, with the aim of differentiating the genomic contexts in which these various types of inhibitors may potentially have superior activity.

Autophagy as a pathogenic mechanism and drug target in lymphoproliferative disorders

Autophagy represents a key mechanism of cytoprotection that can be activated by a variety of extracellular and intracellular stresses and allows the cell to sequester cytoplasmic components and damaged organelles, delivering them to lysosomes for degradation and recycling. However, the autophagy process has also been associated with the death of the cell. It has been demonstrated to be constitutive in some instances and inducible in others, and the idea that it could represent a pathogenetic determinant as well as a possible prognostic tool and a therapeutic target in a plethora of human diseases has recently been considered. Among these, cancer represents a major one. In this review, we recapitulate the critical implications of autophagy in the pathogenesis, progression, and treatment of lymphoproliferative disorders. Leukemias and lymphomas, in fact, represent paradigmatic human diseases in which advances have recently been made in this respect.