Jeff Sharman - Academia.edu (original) (raw)

Papers by Jeff Sharman

Research paper thumbnail of Ibrutinib is an irreversible molecular inhibitor of ITK driving a Th1-selective pressure in T lymphocytes

Blood, 2013

Given its critical role in T-cell signaling, interleukin-2-inducible kinase (ITK) is an appealing... more Given its critical role in T-cell signaling, interleukin-2-inducible kinase (ITK) is an appealing therapeutic target that can contribute to the pathogenesis of certain infectious, autoimmune, and neoplastic diseases. Ablation of ITK subverts Th2 immunity, thereby potentiating Th1-based immune responses. While small-molecule ITK inhibitors have been identified, none have demonstrated clinical utility. Ibrutinib is a confirmed irreversible inhibitor of Bruton tyrosine kinase (BTK) with outstanding clinical activity and tolerability in B-cell malignancies. Significant homology between BTK and ITK alongside in silico docking studies support ibrutinib as an immunomodulatory inhibitor of both ITK and BTK. Our comprehensive molecular and phenotypic analysis confirms ITK as an irreversible T-cell target of ibrutinib. Using ibrutinib clinical trial samples along with well-characterized neoplastic (chronic lymphocytic leukemia), parasitic infection (Leishmania major), and infectious disease (Listeria monocytogenes) models, we establish ibrutinib as a clinically relevant and physiologically potent ITK inhibitor with broad therapeutic utility. This trial was registered at www.clinicaltrials.gov as #NCT01105247 and #NCT01217749.

Research paper thumbnail of An open-label phase 2 trial of entospletinib (GS-9973), a selective Syk inhibitor, in chronic lymphocytic leukemia

Blood, Jan 18, 2015

Small molecule inhibitors of kinases involved in B-cell receptor signaling are an important advan... more Small molecule inhibitors of kinases involved in B-cell receptor signaling are an important advance in managing lymphoid malignancies. Entospletinib (GS-9973) is an oral, selective inhibitor of spleen tyrosine kinase (Syk). This multicenter, phase 2 study enrolled subjects with relapsed or refractory chronic lymphocytic leukemia (CLL; n = 41) or non-Hodgkin lymphoma (n = 145). Subjects received 800 mg of entospletinib twice daily. We report efficacy outcomes in the CLL cohort (n = 41) and safety outcomes in all cohorts (N = 186). The primary end point was a progression-free survival (PFS) rate at 24 weeks in subjects with CLL. The PFS rate at 24 weeks was 70.1% (95% confidence interval [CI]: 51.3%, 82.7%); median PFS was 13.8 months (95% CI: 7.7 months, not reached). The objective response rate was 61.0% (95% CI: 44.5%, 75.8%), including three subjects (7.3%) who achieved nodal response with persistent lymphocytosis. Fifty-four subjects (29.0%) had serious adverse events (SAEs). The...

Research paper thumbnail of Vemurafenib Response in 2 Patients With Posttransplant Refractory BRAF V600E-Mutated Multiple Myeloma

Clinical Lymphoma, Myeloma and Leukemia

Research paper thumbnail of Idelalisib and Rituximab in Relapsed Chronic Lymphocytic Leukemia

New England Journal of Medicine, 2014

Patients with relapsed chronic lymphocytic leukemia (CLL) who have clinically significant coexist... more Patients with relapsed chronic lymphocytic leukemia (CLL) who have clinically significant coexisting medical conditions are less able to undergo standard chemotherapy. Effective therapies with acceptable side-effect profiles are needed for this patient population. In this multicenter, randomized, double-blind, placebo-controlled, phase 3 study, we assessed the efficacy and safety of idelalisib, an oral inhibitor of the delta isoform of phosphatidylinositol 3-kinase, in combination with rituximab versus rituximab plus placebo. We randomly assigned 220 patients with decreased renal function, previous therapy-induced myelosuppression, or major coexisting illnesses to receive rituximab and either idelalisib (at a dose of 150 mg) or placebo twice daily. The primary end point was progression-free survival. At the first prespecified interim analysis, the study was stopped early on the recommendation of the data and safety monitoring board owing to overwhelming efficacy. The median progression-free survival was 5.5 months in the placebo group and was not reached in the idelalisib group (hazard ratio for progression or death in the idelalisib group, 0.15; P<0.001). Patients receiving idelalisib versus those receiving placebo had improved rates of overall response (81% vs. 13%; odds ratio, 29.92; P<0.001) and overall survival at 12 months (92% vs. 80%; hazard ratio for death, 0.28; P=0.02). Serious adverse events occurred in 40% of the patients receiving idelalisib and rituximab and in 35% of those receiving placebo and rituximab. The combination of idelalisib and rituximab, as compared with placebo and rituximab, significantly improved progression-free survival, response rate, and overall survival among patients with relapsed CLL who were less able to undergo chemotherapy. (Funded by Gilead; ClinicalTrials.gov number, NCT01539512.).

Research paper thumbnail of Association of health-related quality of life with gender in patients with B-cell chronic lymphocytic leukemia

Supportive Care in Cancer, 2013

This analysis examined associations between gender and health-related quality of life (HRQOL) in ... more This analysis examined associations between gender and health-related quality of life (HRQOL) in patients with B-cell chronic lymphocytic leukemia (CLL) as they initiate therapy for CLL outside the clinical trial setting. Baseline data were collected as part of Connect® CLL Registry, a prospective observational study initiated in community, academic, and government centers. Patient demographics and clinical characteristics were provided by clinicians. Patients reported HRQOL using the Brief Fatigue Inventory (BFI), EQ-5D, and Functional Assessment of Cancer Therapy-Leukemia (FACT-Leu). Mean scores were analyzed, with statistical significance of differences determined by ANOVA. Multivariate analysis also considered age and line of therapy. Baseline HRQOL data were available for 1,140 patients: 710 (62 %) men and 430 (38 %) women from 161 centers. Patients were predominantly white (89 %) with mean age 69 ± 11 years. Women reported significantly worse global fatigue (P <0.0001), fatigue severity (P <0.0001), and fatigue-related interference (P = 0.0005) versus men (BFI). Pain/discomfort (P = 0.0077), usual activities (P = 0.0015), and anxiety/depression (P = 0.0117) were significantly worse in women than in men (EQ-5D). With women reporting a better social/family score (P = 0.0238) and men reporting a better physical score (P = 0.0002), the mean FACT-G total score did not differ by gender. However, the mean FACT-Leu total score was better among men versus women (P = 0.0223), primarily because the mean leukemia subscale score was significantly better among men (P <0.0001). Multivariate analysis qualitatively confirmed these findings. Connect® CLL Registry results indicate that significant differences exist in certain HRQOL domains, as women reported greater levels of fatigue and worse functioning in physical domains.

Research paper thumbnail of Brentuximab vedotin demonstrates objective responses in a phase 2 study of relapsed/refractory DLBCL with variable CD30 expression

Blood, Jan 26, 2015

Several non-Hodgkin lymphoma (NHL) subtypes, including diffuse large B-cell lymphoma (DLBCL), var... more Several non-Hodgkin lymphoma (NHL) subtypes, including diffuse large B-cell lymphoma (DLBCL), variably express CD30. This phase 2, open-label study evaluated the efficacy of brentuximab vedotin, an anti-CD30 antibody-drug conjugate, in relapsed/refractory CD30(+) NHL. This planned subset analysis of B-cell NHLs includes 49 patients with DLBCL and 19 with other B-cell NHLs. Objective response rate was 44% for DLBCL, including 8 (17%) complete remissions (CRs) with a median duration of 16.6 months thus far (range, 2.7 to 22.7+ months). There was no statistical correlation between response and level of CD30 expression; however, all responding patients had quantifiable CD30 by computer-assisted assessment of immunohistochemistry. DLBCL patients were generally refractory to first-line (76%) and most recent therapies (82%), and 44% of these refractory patients responded (15% CRs). Patients with other B-cell lymphomas also responded: 1 CR, 2 partial responses (PRs) of 6 with gray zone, 1 C...

Research paper thumbnail of Gemcitabine-associated thrombotic microangiopathy

Cancer, 2004

BACKGROUND. Gemcitabine-associated thrombotic microangiopathy (TMA) is believed to be very rare, ... more BACKGROUND. Gemcitabine-associated thrombotic microangiopathy (TMA) is believed to be very rare, with an estimated incidence rate of 0.015%. Indications for gemcitabine are expanding, and comprehensive characterization of this complication is therefore important.

Research paper thumbnail of Cell-cycle reprogramming for PI3K inhibition overrides a relapse-specific C481S BTK mutation revealed by longitudinal functional genomics in mantle cell lymphoma

Cancer discovery, 2014

Despite the unprecedented clinical activity of the Bruton tyrosine kinase (BTK) inhibitor ibrutin... more Despite the unprecedented clinical activity of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib in mantle cell lymphoma (MCL), acquired resistance is common. By longitudinal integrative whole-exome and whole-transcriptome sequencing and targeted sequencing, we identified the first relapse-specific C481S mutation at the ibrutinib binding site of BTK in MCL cells at progression following a durable response. This mutation enhanced BTK and AKT activation and tissue-specific proliferation of resistant MCL cells driven by CDK4 activation. It was absent, however, in patients with primary resistance or progression following transient response to ibrutinib, suggesting alternative mechanisms of resistance. Through synergistic induction of PIK3IP1 and inhibition of PI3K-AKT activation, prolonged early G1 arrest induced by PD 0332991 (palbociclib) inhibition of CDK4 sensitized resistant lymphoma cells to ibrutinib killing when BTK was unmutated, and to PI3K inhibitors independent of C481S m...

Research paper thumbnail of Objective responses in relapsed T-cell lymphomas with single agent brentuximab vedotin

Blood, 2014

Objective responses observed with brentuximab vedotin in 41% of patients with relapsed T-cell lym... more Objective responses observed with brentuximab vedotin in 41% of patients with relapsed T-cell lymphomas, including 54% of AITL patients. • Objective responses observed across a wide range of CD30 expression, including undetectable CD30 expression per central review. This phase 2, open-label, multicenter study evaluated the efficacy and safety of brentuximab vedotin, a CD30-directed antibody-drug conjugate, in relapsed/refractory CD30 1 non-Hodgkin lymphomas. The primary end point was objective response rate (ORR). Key secondary end points included safety, correlation of CD30 expression with response, response duration, and progression-free survival (PFS). Brentuximab vedotin 1.8 mg/kg was administered every 3 weeks until progression or unacceptable toxicity. This planned subset analysis included patients with peripheral T-cell lymphomas (PTCLs; n 5 35), specifically angioimmunoblastic T-cell lymphoma (AITL; n 5 13) and PTCL not otherwise specified (n 5 22). Median age was 64 years; 63% were refractory to most recent therapy. Of 34 evaluable patients, ORR was 41% (8 complete remissions [CRs], 6 partial remissions [PRs])

Research paper thumbnail of Ibrutinib as initial therapy for elderly patients with chronic lymphocytic leukaemia or small lymphocytic lymphoma: an open-label, multicentre, phase 1b/2 trial

The Lancet. Oncology, 2014

Chemoimmunotherapy has led to improved numbers of patients achieving disease response, and longer... more Chemoimmunotherapy has led to improved numbers of patients achieving disease response, and longer overall survival in young patients with chronic lymphocytic leukaemia; however, its application in elderly patients has been restricted by substantial myelosuppression and infection. We aimed to assess safety and activity of ibrutinib, an orally administered covalent inhibitor of Bruton tyrosine kinase (BTK), in treatment-naive patients aged 65 years and older with chronic lymphocytic leukaemia. In our open-label phase 1b/2 trial, we enrolled previously untreated patients at clinical sites in the USA. Eligible patients were aged at least 65 years, and had symptomatic chronic lymphocytic leukaemia or small lymphocytic lymphoma requiring therapy. Patients received 28 day cycles of once-daily ibrutinib 420 mg or ibrutinib 840 mg. The 840 mg dose was discontinued after enrolment had begun because comparable activity of the doses has been shown. The primary endpoint was the safety of the dos...

Research paper thumbnail of Ibrutinib is an irreversible molecular inhibitor of ITK driving a Th1-selective pressure in T lymphocytes

Blood, 2013

Given its critical role in T-cell signaling, interleukin-2-inducible kinase (ITK) is an appealing... more Given its critical role in T-cell signaling, interleukin-2-inducible kinase (ITK) is an appealing therapeutic target that can contribute to the pathogenesis of certain infectious, autoimmune, and neoplastic diseases. Ablation of ITK subverts Th2 immunity, thereby potentiating Th1-based immune responses. While small-molecule ITK inhibitors have been identified, none have demonstrated clinical utility. Ibrutinib is a confirmed irreversible inhibitor of Bruton tyrosine kinase (BTK) with outstanding clinical activity and tolerability in B-cell malignancies. Significant homology between BTK and ITK alongside in silico docking studies support ibrutinib as an immunomodulatory inhibitor of both ITK and BTK. Our comprehensive molecular and phenotypic analysis confirms ITK as an irreversible T-cell target of ibrutinib. Using ibrutinib clinical trial samples along with well-characterized neoplastic (chronic lymphocytic leukemia), parasitic infection (Leishmania major), and infectious disease (Listeria monocytogenes) models, we establish ibrutinib as a clinically relevant and physiologically potent ITK inhibitor with broad therapeutic utility. This trial was registered at www.clinicaltrials.gov as #NCT01105247 and #NCT01217749.

Research paper thumbnail of An open-label phase 2 trial of entospletinib (GS-9973), a selective Syk inhibitor, in chronic lymphocytic leukemia

Blood, Jan 18, 2015

Small molecule inhibitors of kinases involved in B-cell receptor signaling are an important advan... more Small molecule inhibitors of kinases involved in B-cell receptor signaling are an important advance in managing lymphoid malignancies. Entospletinib (GS-9973) is an oral, selective inhibitor of spleen tyrosine kinase (Syk). This multicenter, phase 2 study enrolled subjects with relapsed or refractory chronic lymphocytic leukemia (CLL; n = 41) or non-Hodgkin lymphoma (n = 145). Subjects received 800 mg of entospletinib twice daily. We report efficacy outcomes in the CLL cohort (n = 41) and safety outcomes in all cohorts (N = 186). The primary end point was a progression-free survival (PFS) rate at 24 weeks in subjects with CLL. The PFS rate at 24 weeks was 70.1% (95% confidence interval [CI]: 51.3%, 82.7%); median PFS was 13.8 months (95% CI: 7.7 months, not reached). The objective response rate was 61.0% (95% CI: 44.5%, 75.8%), including three subjects (7.3%) who achieved nodal response with persistent lymphocytosis. Fifty-four subjects (29.0%) had serious adverse events (SAEs). The...

Research paper thumbnail of Vemurafenib Response in 2 Patients With Posttransplant Refractory BRAF V600E-Mutated Multiple Myeloma

Clinical Lymphoma, Myeloma and Leukemia

Research paper thumbnail of Idelalisib and Rituximab in Relapsed Chronic Lymphocytic Leukemia

New England Journal of Medicine, 2014

Patients with relapsed chronic lymphocytic leukemia (CLL) who have clinically significant coexist... more Patients with relapsed chronic lymphocytic leukemia (CLL) who have clinically significant coexisting medical conditions are less able to undergo standard chemotherapy. Effective therapies with acceptable side-effect profiles are needed for this patient population. In this multicenter, randomized, double-blind, placebo-controlled, phase 3 study, we assessed the efficacy and safety of idelalisib, an oral inhibitor of the delta isoform of phosphatidylinositol 3-kinase, in combination with rituximab versus rituximab plus placebo. We randomly assigned 220 patients with decreased renal function, previous therapy-induced myelosuppression, or major coexisting illnesses to receive rituximab and either idelalisib (at a dose of 150 mg) or placebo twice daily. The primary end point was progression-free survival. At the first prespecified interim analysis, the study was stopped early on the recommendation of the data and safety monitoring board owing to overwhelming efficacy. The median progression-free survival was 5.5 months in the placebo group and was not reached in the idelalisib group (hazard ratio for progression or death in the idelalisib group, 0.15; P<0.001). Patients receiving idelalisib versus those receiving placebo had improved rates of overall response (81% vs. 13%; odds ratio, 29.92; P<0.001) and overall survival at 12 months (92% vs. 80%; hazard ratio for death, 0.28; P=0.02). Serious adverse events occurred in 40% of the patients receiving idelalisib and rituximab and in 35% of those receiving placebo and rituximab. The combination of idelalisib and rituximab, as compared with placebo and rituximab, significantly improved progression-free survival, response rate, and overall survival among patients with relapsed CLL who were less able to undergo chemotherapy. (Funded by Gilead; ClinicalTrials.gov number, NCT01539512.).

Research paper thumbnail of Association of health-related quality of life with gender in patients with B-cell chronic lymphocytic leukemia

Supportive Care in Cancer, 2013

This analysis examined associations between gender and health-related quality of life (HRQOL) in ... more This analysis examined associations between gender and health-related quality of life (HRQOL) in patients with B-cell chronic lymphocytic leukemia (CLL) as they initiate therapy for CLL outside the clinical trial setting. Baseline data were collected as part of Connect® CLL Registry, a prospective observational study initiated in community, academic, and government centers. Patient demographics and clinical characteristics were provided by clinicians. Patients reported HRQOL using the Brief Fatigue Inventory (BFI), EQ-5D, and Functional Assessment of Cancer Therapy-Leukemia (FACT-Leu). Mean scores were analyzed, with statistical significance of differences determined by ANOVA. Multivariate analysis also considered age and line of therapy. Baseline HRQOL data were available for 1,140 patients: 710 (62 %) men and 430 (38 %) women from 161 centers. Patients were predominantly white (89 %) with mean age 69 ± 11 years. Women reported significantly worse global fatigue (P <0.0001), fatigue severity (P <0.0001), and fatigue-related interference (P = 0.0005) versus men (BFI). Pain/discomfort (P = 0.0077), usual activities (P = 0.0015), and anxiety/depression (P = 0.0117) were significantly worse in women than in men (EQ-5D). With women reporting a better social/family score (P = 0.0238) and men reporting a better physical score (P = 0.0002), the mean FACT-G total score did not differ by gender. However, the mean FACT-Leu total score was better among men versus women (P = 0.0223), primarily because the mean leukemia subscale score was significantly better among men (P <0.0001). Multivariate analysis qualitatively confirmed these findings. Connect® CLL Registry results indicate that significant differences exist in certain HRQOL domains, as women reported greater levels of fatigue and worse functioning in physical domains.

Research paper thumbnail of Brentuximab vedotin demonstrates objective responses in a phase 2 study of relapsed/refractory DLBCL with variable CD30 expression

Blood, Jan 26, 2015

Several non-Hodgkin lymphoma (NHL) subtypes, including diffuse large B-cell lymphoma (DLBCL), var... more Several non-Hodgkin lymphoma (NHL) subtypes, including diffuse large B-cell lymphoma (DLBCL), variably express CD30. This phase 2, open-label study evaluated the efficacy of brentuximab vedotin, an anti-CD30 antibody-drug conjugate, in relapsed/refractory CD30(+) NHL. This planned subset analysis of B-cell NHLs includes 49 patients with DLBCL and 19 with other B-cell NHLs. Objective response rate was 44% for DLBCL, including 8 (17%) complete remissions (CRs) with a median duration of 16.6 months thus far (range, 2.7 to 22.7+ months). There was no statistical correlation between response and level of CD30 expression; however, all responding patients had quantifiable CD30 by computer-assisted assessment of immunohistochemistry. DLBCL patients were generally refractory to first-line (76%) and most recent therapies (82%), and 44% of these refractory patients responded (15% CRs). Patients with other B-cell lymphomas also responded: 1 CR, 2 partial responses (PRs) of 6 with gray zone, 1 C...

Research paper thumbnail of Gemcitabine-associated thrombotic microangiopathy

Cancer, 2004

BACKGROUND. Gemcitabine-associated thrombotic microangiopathy (TMA) is believed to be very rare, ... more BACKGROUND. Gemcitabine-associated thrombotic microangiopathy (TMA) is believed to be very rare, with an estimated incidence rate of 0.015%. Indications for gemcitabine are expanding, and comprehensive characterization of this complication is therefore important.

Research paper thumbnail of Cell-cycle reprogramming for PI3K inhibition overrides a relapse-specific C481S BTK mutation revealed by longitudinal functional genomics in mantle cell lymphoma

Cancer discovery, 2014

Despite the unprecedented clinical activity of the Bruton tyrosine kinase (BTK) inhibitor ibrutin... more Despite the unprecedented clinical activity of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib in mantle cell lymphoma (MCL), acquired resistance is common. By longitudinal integrative whole-exome and whole-transcriptome sequencing and targeted sequencing, we identified the first relapse-specific C481S mutation at the ibrutinib binding site of BTK in MCL cells at progression following a durable response. This mutation enhanced BTK and AKT activation and tissue-specific proliferation of resistant MCL cells driven by CDK4 activation. It was absent, however, in patients with primary resistance or progression following transient response to ibrutinib, suggesting alternative mechanisms of resistance. Through synergistic induction of PIK3IP1 and inhibition of PI3K-AKT activation, prolonged early G1 arrest induced by PD 0332991 (palbociclib) inhibition of CDK4 sensitized resistant lymphoma cells to ibrutinib killing when BTK was unmutated, and to PI3K inhibitors independent of C481S m...

Research paper thumbnail of Objective responses in relapsed T-cell lymphomas with single agent brentuximab vedotin

Blood, 2014

Objective responses observed with brentuximab vedotin in 41% of patients with relapsed T-cell lym... more Objective responses observed with brentuximab vedotin in 41% of patients with relapsed T-cell lymphomas, including 54% of AITL patients. • Objective responses observed across a wide range of CD30 expression, including undetectable CD30 expression per central review. This phase 2, open-label, multicenter study evaluated the efficacy and safety of brentuximab vedotin, a CD30-directed antibody-drug conjugate, in relapsed/refractory CD30 1 non-Hodgkin lymphomas. The primary end point was objective response rate (ORR). Key secondary end points included safety, correlation of CD30 expression with response, response duration, and progression-free survival (PFS). Brentuximab vedotin 1.8 mg/kg was administered every 3 weeks until progression or unacceptable toxicity. This planned subset analysis included patients with peripheral T-cell lymphomas (PTCLs; n 5 35), specifically angioimmunoblastic T-cell lymphoma (AITL; n 5 13) and PTCL not otherwise specified (n 5 22). Median age was 64 years; 63% were refractory to most recent therapy. Of 34 evaluable patients, ORR was 41% (8 complete remissions [CRs], 6 partial remissions [PRs])

Research paper thumbnail of Ibrutinib as initial therapy for elderly patients with chronic lymphocytic leukaemia or small lymphocytic lymphoma: an open-label, multicentre, phase 1b/2 trial

The Lancet. Oncology, 2014

Chemoimmunotherapy has led to improved numbers of patients achieving disease response, and longer... more Chemoimmunotherapy has led to improved numbers of patients achieving disease response, and longer overall survival in young patients with chronic lymphocytic leukaemia; however, its application in elderly patients has been restricted by substantial myelosuppression and infection. We aimed to assess safety and activity of ibrutinib, an orally administered covalent inhibitor of Bruton tyrosine kinase (BTK), in treatment-naive patients aged 65 years and older with chronic lymphocytic leukaemia. In our open-label phase 1b/2 trial, we enrolled previously untreated patients at clinical sites in the USA. Eligible patients were aged at least 65 years, and had symptomatic chronic lymphocytic leukaemia or small lymphocytic lymphoma requiring therapy. Patients received 28 day cycles of once-daily ibrutinib 420 mg or ibrutinib 840 mg. The 840 mg dose was discontinued after enrolment had begun because comparable activity of the doses has been shown. The primary endpoint was the safety of the dos...