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Biomedical subjects

Paul G Richardson

Publications and source records attributed to Paul G Richardson.

At least 19 recordsLinked to original sources
PubMed2026

Teclistamab versus lenalidomide-dexamethasone in high-risk smoldering multiple myeloma: a randomized phase 2 trial.

Teclistamab, a B cell maturation antigen-targeting bispecific antibody, has demonstrated substantial activity in relapsed multiple myeloma (MM), particularly in earlier lines of therapy, and may have higher efficacy in high-risk smoldering MM (HR-SMM) with a more functional immune system. In the randomized phase 2 ImmunoPRISM trial, we compared fixed-duration teclistamab with lenalidomide-dexamethasone (Rd) in HR-SMM. After a six-patient safety run-in, patients were randomized 2:1 to teclistamab or Rd. The primary endpoint was complete response (CR) rate. As of 26 May 2026, 59 patients were treated-45 received teclistamab and 14 received Rd. Teclistamab treatment induced a CR in 77.8% patients versus 0% with Rd, and minimal residual disease negativity at 10-5 in 82.2% patients. At a median follow-up of 24.5 months, 2-year progression-free survival was 92% with teclistamab versus 49% with Rd. Overall, response rates, duration of response and time to progression (TTP) were significantly improved in teclistamab compared to Rd. Toxicities in the teclistamab arm included grades 1-2 cytokine release syndrome, no neurotoxicity and no increase in grade 3 infections compared to Rd (20% versus 21%). No deaths occurred in either arm. Teclistamab represents a highly active immune-interception strategy for HR-SMM. ClinicalTrials.gov registration: NCT05469893 .

Journal Article↗
PubMed2026

Phase IIB, Randomized, Double-Blind, Placebo-Controlled Clinical Trial of Intravenous Defibrotide for the Prevention and Treatment of Respiratory Distress and Cytokine Release Syndrome in COVID-19.

INTRODUCTION: Endothelial dysfunction is key in COVID-19 pathogenesis. This randomized, double-blind phase IIb trial investigated continuous intravenous infusion of defibrotide in patients hospitalized with SARS-CoV-2 infection and respiratory failure. METHODS: One-hundred and fifty patients were randomized (2:1) to defibrotide or placebo, stratified by disease severity (WHO COVID-19 severity scale 4/5 vs. 6). The primary endpoint was clinical improvement time (days from first improvement through Day 30). RESULTS: Median clinical improvement time was not significantly different with defibrotide versus placebo (15.0 [IQR: 0-24] vs. 20.0 [IQR: 9-25] days; p = 0.10). Day-30 (23.0% vs. 22.0%) and Day-60 (26.0% vs. 22.0%) mortality, reduction in mean fraction of inspired oxygen during treatment, and median duration of hospitalization did not differ with defibrotide versus placebo. Defibrotide demonstrated favorable safety, with no differences versus placebo in serious adverse events (34.0% vs. 36.0%), hypotension (16.0% vs. 12.0%), or hemorrhage (13.0% vs. 8.0%). Exploratory pre-specified biomarker analyses showed greater early d-dimer reduction and lymphocyte recovery with defibrotide, although these results require validation. CONCLUSION: Continuous intravenous infusion of defibrotide was safe but did not improve clinical outcomes in severe COVID-19. Further analyses will explore mechanistic actions and pharmacokinetics of defibrotide and the pathophysiology of endothelial dysfunction in COVID-19. TRIAL REGISTRATION: EudraCT identifier: 2020-001409-21. CLINICALTRIALS: gov identifier: NCT04348383.

Adult↗
PubMed2006

BIRB 796 enhances cytotoxicity triggered by bortezomib, heat shock protein (Hsp) 90 inhibitor, and dexamethasone via inhibition of p38 mitogen-activated protein kinase/Hsp27 pathway in multiple myeloma cell lines and inhibits paracrine tumour growth.

We have previously shown that heat shock protein (Hsp) 27 or its upstream activator p38 mitogen-activated protein kinase (MAPK) confers resistance to bortezomib and dexamethasone (Dex) in multiple myeloma (MM) cells. This study examined anti-MM activity of a novel p38 MAPK inhibitor, BIRB 796, alone and in combination with conventional and novel therapeutic agents. BIRB 796 blocked baseline and bortezomib-triggered upregulation of p38 MAPK and Hsp27 phosphorylation, thereby enhancing cytotoxicity and caspase activation. The Hsp90 inhibitor 17-allylamino-17-demethoxy-geldanamycin (17-AAG) upregulated protein expression and phosphorylation of Hsp27; conversely, BIRB 796 inhibited this phosphorylation and enhanced 17-AAG-induced cytotoxicity. Importantly, BIRB 796 inhibited Hsp27 phosphorylation induced by 17-AAG plus bortezomib, thereby enhancing cytotoxicity. In bone marrow stromal cells (BMSC), BIRB 796 inhibited phosphorylation of p38 MAPK and secretion of interleukin-6 (IL-6) and vascular endothelial growth factor triggered by either tumour necrosis factor-alpha or tumour growth factor-beta1. BIRB 796 also inhibited IL-6 secretion induced in BMSCs by adherence to MM cells, thereby inhibiting tumour cell proliferation. These studies therefore suggest that BIRB 796 overcomes drug-resistance in the BM microenvironment, providing the framework for clinical trials of a p38 MAPK inhibitor, alone and in combination with bortezomib, Hsp90 inhibitor, or Dex, to improve patient outcome in MM.

Antineoplastic Agents, Hormonal↗
PubMed2006

Activity and safety of bortezomib in multiple myeloma patients with advanced renal failure: a multicenter retrospective study.

Patients with multiple myeloma (MM) frequently present with concomitant renal dysfunction, and those requiring dialysis have particularly poor outcomes. Bortezomib is a reversible proteasome inhibitor with significant activity in MM. This retrospective case analysis evaluated the feasibility and activity of bortezomib-based therapy in MM patients (n = 24) requiring dialysis support for advanced renal failure. All but 1 patient were undergoing dialysis at the time of therapy. Patients received bortezomib alone or bortezomib-based combination therapy. Among 20 patients with available response data, overall response rate (complete response [CR] + partial response) was 75%, with 30% CR + near CR. One patient was spared dialysis, and 3 other patients became independent of dialysis following bortezomib-based treatment. These encouraging results suggest that bortezomib or bortezomib-based regimens can be used in MM patients requiring dialysis, with manageable toxicities. Further studies will more formally evaluate the impact of bortezomib-based regimens in this patient population.

Adult↗
PubMed2006

A randomized phase 2 study of lenalidomide therapy for patients with relapsed or relapsed and refractory multiple myeloma.

This multicenter, open-label, randomized phase 2 study evaluated 2 dose regimens of lenalidomide for relapsed, refractory myeloma. Seventy patients were randomized to receive either 30 mg once-daily or 15 mg twice-daily oral lenalidomide for 21 days of every 28-day cycle. Patients with progressive or stable disease after 2 cycles received dexamethasone. Analysis of the first 70 patients showed increased grade 3/4 myelo-suppression in patients receiving 15 mg twice daily (41% versus 13%, P = .03). An additional 32 patients received 30 mg once daily. Responses were evaluated according to European Group for Blood and Marrow Transplantation (EBMT) criteria. Overall response rate (complete, partial, or minor) to lenalidomide alone was 25% (24% for once-daily and 29% for twice-daily lenalidomide). Median overall survival in 30-mg once-daily and twice-daily groups was 28 and 27 months, respectively. Median progression-free survival was 7.7 months on once-daily versus 3.9 months on twice-daily lenalidomide (P = .2). Dexamethasone was added in 68 patients and 29% responded. Time to first occurrence of clinically significant grade 3/4 myelosuppression was shorter in the twice-daily group (1.8 vs 5.5 months, P = .05). Significant peripheral neuropathy and deep vein thrombosis each occurred in only 3%. Lenalidomide is active and well tolerated in relapsed, refractory myeloma, with the 30-mg once-daily regimen providing the basis for future studies as monotherapy and with dexamethasone.

Adult↗
PubMed2006

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.

Bone Diseases↗
PubMed2006

Frequency, characteristics, and reversibility of peripheral neuropathy during treatment of advanced multiple myeloma with bortezomib.

PURPOSE: To determine the frequency, characteristics, and reversibility of peripheral neuropathy from bortezomib treatment of advanced multiple myeloma. PATIENTS AND METHODS: Peripheral neuropathy was assessed in two phase II studies in 256 patients with relapsed and/or refractory myeloma treated with bortezomib 1.0 or 1.3 mg/m2 intravenous bolus on days 1, 4, 8, and 11, every 21 days, for up to eight cycles. Peripheral neuropathy was evaluated at baseline, during the study, and after the study by patient-reported symptoms using the Functional Assessment of Cancer Therapy Scale/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) questionnaire and neurologic examination. During the study, peripheral neuropathy was also evaluated by investigator assessment. A subset of patients underwent nerve conduction studies (n = 13). RESULTS: Before treatment, 194 (81%) of 239 patients had peripheral neuropathy by FACT/GOG-Ntx questionnaire, and 203 (83%) of 244 patients had peripheral neuropathy by neurologic examination. Treatment-emergent neuropathy was reported in 35% of patients, including 37% (84 of 228 patients) receiving bortezomib 1.3 mg/m2 and 21% (six of 28 patients) receiving bortezomib 1.0 mg/m2. Grade 1 or 2, 3, and 4 neuropathy occurred in 22%, 13%, and 0.4% of patients, respectively. The incidence of grade > or = 3 neuropathy was higher among patients with baseline neuropathy by FACT/GOG-Ntx questionnaire compared with patients without baseline neuropathy (14% v 4%, respectively). In all 256 patients, neuropathy led to dose reduction in 12% and discontinuation in 5%. Of 35 patients with neuropathy > or = grade 3 and/or requiring discontinuation, resolution to baseline or improvement occurred in 71%. CONCLUSION: Bortezomib-associated peripheral neuropathy seemed reversible in the majority of patients after dose reduction or discontinuation. Although severe neuropathy was more frequent in the presence of baseline neuropathy, the overall occurrence was independent of baseline neuropathy or type of prior therapy.

Adult↗
PubMed2006

Extended follow-up of a phase II trial in relapsed, refractory multiple myeloma:: final time-to-event results from the SUMMIT trial.

BACKGROUND: Bortezomib, a first-in-class proteasome inhibitor, has shown clinical activity in relapsed, refractory multiple myeloma in a pivotal Phase II trial, SUMMIT. METHODS: Patients received bortezomib 1.3 mg/m(2) on Days 1, 4, 8, and 11 followed by a 10-day rest period for up to 8 cycles. Dexamethasone 20 mg on the day of and the day after bortezomib was permitted for suboptimal response. Extended treatment beyond 8 cycles was offered to patients whose physicians felt they would benefit from additional therapy. Follow-up was conducted in all patients for a median of 23 months, an additional 13 months from the original report. RESULTS: Of 202 patients enrolled in SUMMIT, 193 were evaluable for response. Seven (4%) patients achieved a complete response, 12 (6%) achieved a nearly complete response, 34 (18%) achieved a partial response, and 14 (7%) had a minimal response while on bortezomib. The updated median duration of response to bortezomib alone was 12.7 months. The median overall time to progression for all SUMMIT patients was 7 months. For responding patients, the median time to progression was 13.9 months, whereas for those with progressive disease (PD) or who were not evaluable, the median time to progression was 1.3 months. The median overall survival (OS) for all SUMMIT patients was 17.0 months. Whereas the median OS for patients with PD or who were not evaluable was 8 months, the median OS for responding patients was not reached at 23 months of follow-up. CONCLUSIONS: These data demonstrate that treatment with bortezomib results in meaningful long-term benefit for patients with relapsed and refractory myeloma.

Adult↗
PubMed2006

Perifosine, an oral bioactive novel alkylphospholipid, inhibits Akt and induces in vitro and in vivo cytotoxicity in human multiple myeloma cells.

Perifosine is a synthetic novel alkylphospholipid, a new class of antitumor agents which targets cell membranes and inhibits Akt activation. Here we show that baseline phosphorylation of Akt in multiple myeloma (MM) cells is completely inhibited by perifosine [octadecyl-(1,1-dimethyl-piperidinio-4-yl)-phosphate] in a time- and dose-dependent fashion, without inhibiting phosphoinositide-dependent protein kinase 1 phosphorylation. Perifosine induces significant cytotoxicity in both MM cell lines and patient MM cells resistant to conventional therapeutic agents. Perifosine does not induce cytotoxicity in peripheral blood mononuclear cells. Neither exogenous interleukin-6 (IL-6) nor insulinlike growth factor 1 (IGF-1) overcomes Perifosine-induced cytotoxicity. Importantly, Perifosine induces apoptosis even of MM cells adherent to bone marrow stromal cells. Perifosine triggers c-Jun N-terminal kinase (JNK) activation, followed by caspase-8/9 and poly (ADP)-ribose polymerase cleavage. Inhibition of JNK abrogates perifosine-induced cytotoxicity, suggesting that JNK plays an essential role in perifosine-induced apoptosis. Interestingly, phosphorylation of extracellular signal-related kinase (ERK) is increased by perifosine; conversely, MEK inhibitor synergistically enhances Perifosine-induced cytotoxicity in MM cells. Furthermore, perifosine augments dexamethasone, doxorubicin, melphalan, and bortezomib-induced MM cell cytotoxicity. Finally, perifosine demonstrates significant antitumor activity in a human plasmacytoma mouse model, associated with down-regulation of Akt phosphorylation in tumor cells. Taken together, our data provide the rationale for clinical trials of perifosine to improve patient outcome in MM.

Cell Division↗
PubMed2006

Beyond single-agent bortezomib: combination regimens in relapsed multiple myeloma.

PURPOSE OF REVIEW: Bortezomib-based combinations are being investigated in relapsed or refractory multiple myeloma with the aim of improving outcomes. This review presents recent data from clinical trials of these combinations and discusses their implications. RECENT FINDINGS: Preclinical findings indicating additive or synergistic activity of bortezomib plus conventional and novel agents for multiple myeloma appear to be supported by clinical studies of bortezomib-based combinations. Bortezomib combined with a broad set of active agents results in enhanced response rates, including high complete response rates. Encouraging responses to bortezomib and its combinations are also seen in elderly patients, patients with adverse prognostic factors such as refractory disease and increased beta2-microglobulin, patients with cytogenetic abnormalities such as chromosome 13 deletion, advanced bone disease, extramedullary involvement, and patients with renal impairment, including patients with renal failure requiring dialysis. Toxicities are predictable and manageable and comparable to those seen with bortezomib monotherapy. SUMMARY: Bortezomib-based combinations show promising activity in relapsed or refractory multiple myeloma, including reversal of chemoresistance to previously used agents. As high complete and overall response rates translate into longer survival, bortezomib-based combinations appear likely to have a significant impact on the multiple myeloma treatment algorithm and on the course of the disease itself.

Antineoplastic Agents↗
PubMed2006

Novel therapeutic strategies targeting growth factor signalling cascades in multiple myeloma.

Multiple myeloma (MM) remains largely incurable despite conventional and high-dose therapies, and novel biologically based treatment approaches are urgently required. Recent studies demonstrate that various growth factors including interleukin (IL)-6, insulin-like growth factor (IGF)-1, vascular endothelial growth factor (VEGF), the tumour necrosis factor (TNF) family proteins, Wnt, and Notch family members play an important role in MM pathogenesis, and mediate tumour cell proliferation, drug resistance and migration in the bone marrow (BM) milieu. Targeting growth factors, therefore, represents a promising therapeutic strategy in MM. Novel agents inhibiting growth factor signalling cascades can target ligands, receptors, and/or downstream signalling cascade proteins in MM cells and the BM microenvironment. Combinations of these novel agents with conventional therapies may not only enhance cytotoxicity, but also avoid drug resistance and thereby improve patient outcome in MM.

Animals↗
PubMed2006

Bortezomib: proteasome inhibition as an effective anticancer therapy.

VELCADER (bortezomib, Millennium Pharmaceuticals, Inc., Cambridge, MA, and Johnson & Johnson Pharmaceutical Research & Development, L.L.C., Raritan, NJ) is a first-in-class proteasome inhibitor developed specifically for use as an antineoplastic agent. Inhibition of the proteasome results in disruption of homeostatic mechanisms within the cell that can lead to cell death. Bortezomib's first indication, for the treatment of relapsed myeloma in patients who have received at least two prior treatments and progressed on their previous treatment, was based in part on the magnitude of activity demonstrated in phase II trials. Bortezomib is currently indicated for patients who have received at least one prior therapy in the United States and European Union, although patients in the European Union must have already undergone bone marrow transplantation or be unsuitable for the procedure. A phase III trial demonstrated the superiority of bortezomib over high-dose dexamethasone in response rate, time to progression, and survival in patients with myeloma who had relapsed after 1-3 prior therapies. Clinical development is ongoing to investigate its activity as monotherapy and in combination regimens for the treatment of non-Hodgkin's lymphoma, solid tumors, and earlier presentations of myeloma.

Boronic Acids↗
PubMed2006

Current therapeutic uses of lenalidomide in multiple myeloma.

Thalidomide has demonstrated a broad spectrum of pharmacological and immunological effects, with potential therapeutic applications that span a wide spectrum of diseases: cancer and related conditions; infectious diseases; autoimmune diseases; dermatological diseases; and other disorders such as sarcoidosis, macular degeneration and diabetic retinopathy. Immunomodulatory derivative lenalidomide has more potent antitumour and anti-inflammatory effects. The molecular mechanisms of antitumour activity of lenalidomide have been extensively studied in multiple myeloma (MM). It directly induces growth arrest and/or apoptosis of even drug-resistant MM cells; inhibits binding of MM cells to bone marrow extracellular matrix proteins and stromal cells; modulates cytokine secretion and inhibits angiogenesis in the bone marrow milieu; and augments host antitumour immunity. Importantly, lenalidomide induces significant clinical responses even in patients with relapsed/refractory MM. Therefore, lenalidomide represents a new class of antitumour agents that is useful in the treatment of MM. Lenalidomide has received fast track designation from the FDA for the treatment of MM and myelodysplastic syndromes.

Animals↗
PubMed2006

Lenalidomide in multiple myeloma.

Current therapies for multiple myeloma include steroids, alkylating agents and high-dose chemotherapy with autologous stem cell transplant. These approaches are typically associated with initially good response rates, but they ultimately fail as a result of disease progression. New therapies that overcome resistance, lower toxicity and maintain remission are needed. Recent advances in the treatment of multiple myeloma include bortezomib and thalidomide. Lenalidomide (Revlimid) is an immunomodulatory drug that has undergone rapid clinical development in multiple myeloma and was recently approved by the US FDA for use in patients with relapsed disease. Clinical trials demonstrate that lenalidomide, particularly in combination with dexamethasone, produces durable clinical responses in patients with relapsed and refractory disease and is generally well tolerated, with manageable toxicities. This review summarizes the profile of lenalidomide and the current evidence for its efficacy in multiple myeloma.

Angiogenesis Inhibitors↗
PubMed2006

Recent advances in the treatment of Multiple Myeloma.

Multiple Myeloma (MM) remains an incurable plasma cell malignancy in the bone marrow (BM) despite conventional therapies as well as high-dose therapies with stem cell support. Therefore novel biologically-based therapeutic approaches are required. Recently, intensive laboratory and preclinical studies have identified and validated therapeutic molecular targets in MM. In particular, recognition of the biologic significance of the BM microenvironment in MM pathogenesis and as a potential target for novel therapeutics has derived several promising approaches. Novel FDA approved agents including thalidomide/thalomid, its immunomodulatory derivatives lenalidomide/Revlimid, and proteasome inhibitor bortezomib/Velcade are directed at molecular targets not only in MM cells but also in its BM milieu, and have already achieved promising results in clinical studies. Here we discuss the mechanisms of action of these novel drugs and their clinical application, alone or combined with conventional or novel drugs.

Antineoplastic Agents↗
PubMed2006

Proteasome inhibition as a new therapeutic principle in hematological malignancies.

The intracellular concentration of proteins in both normal and tumor cells are regulated by the balance between the rates of protein synthesis vs. degradation. The ubiquitin-proteasome pathway is the main intracellular cascade for controlled degradation of proteins and has attracted in recent years major interest not only because of its biochemical complexity and the intricate regulation of its function, but also because diverse cell cycle regulators and modulators of apoptosis are subject to regulation by proteasome function, and can therefore be significantly affected by small molecule inhibitors of the proteolytic activity of the proteasome. In fact, bortezomib, the prototypic member of this class of agents, was recently approved by the U.S. Food and Drug Administration for the treatment of advanced multiple myeloma patients. This review article focuses on the exciting recent progress in the use of proteasome inhibitors, with emphasis on the bench-to-bedside research effort which provided the foundation for clinical development of bortezomib for the treatment of multiple myeloma, as well as other hematologic malignancies, such as mantle cell lymphoma.

Animals↗