FDA Approves Glofitamab for Relapsed or Refractory Large B-Cell Lymphomas

SUMMARY: The FDA on June 15, 2023, granted accelerated approval to Glofitamab-gxbm (COLUMVI®) for Relapsed or Refractory Diffuse Large B-Cell Lymphoma, Not Otherwise Specified (DLBCL, NOS) or Large B-Cell Lymphoma (LBCL) arising from Follicular Lymphoma, after two or more lines of systemic therapy.

The American Cancer Society estimates that in 2023, about 80,550 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,180 individuals will die of this disease. Diffuse Large B-Cell Lymphoma (DLBCL) is the most common of the aggressive Non-Hodgkin lymphomas in the United States, and the incidence has steadily increased 3-4% each year. More than half of patients are 65 or older at the time of diagnosis and the incidence is likely to increase with aging of the American population. The etiology of Diffuse Large B-Cell Lymphoma is unknown. Contributing risk factors include immunosuppression (AIDS, transplantation setting, autoimmune diseases), UltraViolet radiation, pesticides, hair dyes, and diet.

DLBCL is a neoplasm of large B cells and the most common chromosome abnormality involves alterations of the BCL-6 gene at the 3q27 locus, which is critical for germinal center formation. Two major molecular subtypes of DLBCL arising from different genetic mechanisms have been identified, using Gene Expression Profiling: Germinal Center B-cell-like (GCB) and Activated B-Cell-like (ABC). Patients in the GCB subgroup have a higher 5-year survival rate, independent of clinical IPI (International Prognostic Index) risk score, whereas patients in the ABC subgroup have a significantly worse outcome. Regardless, R-CHOP regimen (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone), given every 21 days, for 6 cycles, delivered with curative intent, is the current standard of care for patients of all ages, with newly diagnosed DLBCL, regardless of molecular subtype. Approximately 30-40% of patients experience disease progression or relapse, during the first 2 years and attempts to improve on R-CHOP regimen have not been successful. Maintenance treatment strategy following R-CHOP, to better control the disease, delay disease progression and improve long term survival, have included Autologous Stem Cell Transplantation, CAR T-cell therapy, maintenance treatment with agents such as oral protein kinase inhibitor Enzastaurin and Everolimus. Outcomes for transplant-ineligible patients with Relapsed/Refractory DLBCL patients remain poor. There is a critical unmet need for this patient group.

Glofitamab is a CD20-directed CD3 T-cell engager bispecific antibody, designed to target CD20 on the surface of B cells and CD3 on the surface of T cells. This dual targeting activates and redirects a patient’s existing T cells to engage and eliminate target B cells by releasing cytotoxic proteins into the B cells. Glofitamab differs from other CD20-directed CD3 T-cell engager bispecific antibodies in that it has two anti-CD20 binding domains. It is therefore bivalent for the tumor antigen and monovalent for the T-cell CD3 protein. Further, it is a time-limited therapy.

The present FDA approval was based on positive data from the NP30179 study, which is a Phase I/II, multicenter, open-label, dose-escalation and expansion study, evaluating the safety, efficacy and pharmacokinetics of Glofitamab in patients with Relapsed or Refractory Diffuse Large B-Cell Lymphoma (DLBCL). Once the recommended Phase II dose of Glofitamab was established, patients with DLBCL who had previously received at least two lines of therapy were enrolled in the expansion cohorts. This expansion cohort included 154 patients (N=154), who had Relapsed or Refractory disease, and had received at least two previous lines of therapy including at least one anti-CD20 antibody-containing regimen and at least one anthracycline-containing regimen.

Eighty percent of patients had Relapsed or Refractory DLBCL, and 20% had LBCL arising from Follicular Lymphoma. Approximately 85% of patients were refractory to their most recent therapy and 33% had received prior CAR T-cell therapy. This study excluded patients with active or previous Central Nervous System lymphoma or disease. Treatment consisted of a single dose of Obinutuzumab 1,000 mg IV on Cycle 1 Day 1, to deplete circulating and lymphoid tissue B cells and to mitigate Cytokine Release Syndrome, followed by fixed-duration Glofitamab monotherapy administered by IV infusion according to a step-up dosing schedule (2.5 mg on Day 8 of Cycle 1 and 10 mg on Day 15 of Cycle 1), then 30 mg on Day 1 of each subsequent cycle for a maximum of 12 cycles. The cycle length was 21 days. Patients were hospitalized for the first dose of Glofitamab and subsequent doses were administered in the outpatient setting unless Cytokine Release Syndrome of Grade 2 or higher was reported after the first dose. The Primary end point was Complete Response (CR) rate according to assessment by an Independent Review Committee. Key Secondary end points included Duration of Response, Progression Free Survival, and Safety. The efficacy analysis included 132 patients.

The Overall Response Rate (ORR) was 56% with a Complete Response rate of 43%. With an estimated median follow up of 11.6 months among responders, the estimated median Duration of Response was 18.4 months. Further, 68.5% of patients who achieved a response continued to respond for 9 months or longer. The median Time to Response was 42 days. The most common adverse reactions, excluding laboratory abnormalities were Cytokine Release Syndrome (CRS), musculoskeletal pain, rash, and fatigue. CRS occurred in 70% (with 4.1% Grade 3 or higher CRS), Immune Effector Cell-Associated Neurotoxicity (ICANS) in 4.8%, serious infections in 16%, and tumor flare in 12%. The most common Grade 3 to 4 laboratory abnormalities were lymphopenia and neutropenia, decrease in serum phosphate and fibrinogen levels, and increase in serum uric acid.

It was concluded that a fixed duration treatment of off-the-shelf therapy with Glofitamab induced durable Complete Responses, among patients with Relapsed or Refractory Diffuse Large B-Cell Lymphoma.

Glofitamab for Relapsed or Refractory Diffuse Large B-Cell Lymphoma. Dickinson MJ, Carlo-Stella C, Morschauser F, et al. N Eng J Med. 2022;387:2220-2231.

FDA Approves BiSpecific Antibody EPKINLY® for Aggressive Non Hodgkin Lymphomas

SUMMARY: The FDA on May 19, 2023, granted accelerated approval to Epcoritamab-bysp (EPKINLY®) for relapsed or refractory Diffuse Large B-Cell Lymphoma (DLBCL) not otherwise specified, including DLBCL arising from indolent lymphoma, and High-Grade B-Cell Lymphoma after two or more lines of systemic therapy. The American Cancer Society estimates that in 2023, about 80,550 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,180 individuals will die of this disease. Diffuse Large B-Cell Lymphoma (DLBCL) is the most common of the aggressive Non-Hodgkin lymphomas in the United States, and the incidence has steadily increased 3-4% each year. More than half of patients are 65 or older at the time of diagnosis and the incidence is likely to increase with aging of the American population. The etiology of Diffuse Large B-Cell Lymphoma is unknown. Contributing risk factors include immunosuppression (AIDS, transplantation setting, autoimmune diseases), UltraViolet radiation, pesticides, hair dyes, and diet.

DLBCL is a neoplasm of large B cells and the most common chromosome abnormality involves alterations of the BCL-6 gene at the 3q27 locus, which is critical for germinal center formation. Two major molecular subtypes of DLBCL arising from different genetic mechanisms have been identified, using Gene Expression Profiling: Germinal Center B-cell-like (GCB) and Activated B-Cell-like (ABC). Patients in the GCB subgroup have a higher 5-year survival rate, independent of clinical IPI (International Prognostic Index) risk score, whereas patients in the ABC subgroup have a significantly worse outcome. Regardless, R-CHOP regimen (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone), given every 21 days, for 6 cycles, delivered with curative intent, is the current standard of care for patients of all ages, with newly diagnosed DLBCL, regardless of molecular subtype. Approximately 30-40% of patients experience disease progression or relapse, during the first 2 years and attempts to improve on R-CHOP regimen have not been successful. Maintenance treatment strategy following R-CHOP, to better control the disease, delay disease progression and improve long term survival, have included Autologous Stem Cell Transplantation, CAR T-cell therapy, maintenance treatment with agents such as oral protein kinase inhibitor Enzastaurin and Everolimus. Outcomes for transplant-ineligible patients with Relapsed/Refractory DLBCL patients remain poor.

Epcoritamab is a CD20-directed CD3 T-cell engager bispecific antibody, designed to target CD20 on the surface of B cells and CD3 on the surface of T cells. This dual targeting activates and redirects a patient’s existing T cells to engage and eliminate target B cells by releasing cytotoxic proteins into the B cells.

EPCORE NHL-1 is an ongoing, open-label, multi-cohort, multicenter, Phase 1/2b, single-arm trial in which the safety, tolerability, pharmacokinetics and preliminary efficacy of Epcoritamab in combination with standard-of-care (SOC) agents are being examined in patients with relapsed, progressive or refractory CD20+ mature B-cell Non-Hodgkin Lymphoma (NHL), including Diffuse Large B-Cell Lymphoma. Phase 1 of the trial consists of a first-in-human, dose-escalation portion, and Phase 2 is the expansion and optimization part.

The Phase 2 expansion cohort included 157 patients with relapsed/refractory Large B-Cell Lymphoma who were previously treated with a median of 3 lines of prior therapy. The median age was 64 years and median time from initial diagnosis was 1.6 yrs. Approximately 39% of patients had received prior CAR T-cell therapy, 20% had prior Autologous Stem Cell Transplantation, 61% had Primary refractory disease and 14% of patients with Diffuse Large B-Cell Lymphoma were confirmed Double Hit/Triple Hit by central FISH. Epcoritamab was administered subcutaneously in 28-day cycles until disease progression or unacceptable toxicity. Mitigation of Cytokine Release Syndrome included step-up dosing and corticosteroid prophylaxis in the first cycle alone. Step-up dosing was 0.16 mg on Day 1, 0.8 mg on Day 8, and 48 mg on Day 15 and Day 22 in Cycle 1, followed by fixed dosing of 48 mg weekly dosing during Cycles 2-3, every other week during Cycle 4-9, and then every four weeks on Day 1 of subsequent cycles. Per protocol, 24-hour hospitalization was required only for the first full dose (48 mg) to ensure close observation of patients. The Primary endpoint was Overall Response Rate (ORR) by Independent Review Committee. Key Secondary endpoints included the Duration of Response (DOR), time to response, Progression Free Survival (PFS), Overall Survival (OS), Complete Response (CR) rate, Safety, and tolerability.

At a median follow-up of 10.7 months, the Overall Response Rate for the total population was 63%, with a Complete Response Rate of 39%. The median Duration of Response was 12.0 months and was Not Reached among complete responders. Overall and Complete Response rates were similar across key prespecified subgroups. The median time to response was 1.4 months. MRD negativity was assessed by a ctDNA NGS assay and 46.4% were MRD negative at any time point on treatment. MRD negativity was reached at a median of 8 weeks for complete responders, and high MRD negativity rates were observed across all prespecified subgroups. MRD-negative responses were durable and correlated with PFS. The most common adverse events were Cytokine Release Syndrome (majority were Grade 1 or 2, with most events occurring after the first full dose), fever and fatigue. Immune effector Cell-Associated Neurotoxicity Syndrome occurred in 6.4% of patients.

It was concluded that subcutaneous single agent Epcoritamab is a convenient, off-the-shelf therapy that resulted in deep and durable responses, including high MRD negativity rates, with manageable safety, in highly refractory patients with Large B-cell lymphoma, including those with prior CAR T-cell exposure.

Epcoritamab, a Novel, Subcutaneous CD3xCD20 Bispecific T-Cell-Engaging Antibody, in Relapsed or Refractory Large B-Cell Lymphoma: Dose Expansion in a Phase I/II Trial. Thieblemont C, Phillips T, Ghesquieres H, et al. J Clin Oncol. 2023;;41:2238-2247.

BRUKINSA® for First Line Treatment of Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma

SUMMARY: The American Cancer Society estimates that for 2023, about 18,740 new cases of Chronic Lymphocytic Leukemia (CLL) will be diagnosed in the US and 4490 patients will die of the disease. CLL accounts for about one-quarter of the new cases of leukemia. The average age of patients diagnosed with CLL is around 70 years, and is rarely seen in people under age 40, and is extremely rare in children.

Bruton’s Tyrosine Kinase (BTK) is a member of the Tec family of kinases, downstream of the B-cell receptor and is predominantly expressed in B-cells. It is a mediator of B-cell receptor signaling in normal and transformed B-cells. BTK inhibitors inhibit cell proliferation and promotes programmed cell death (Apoptosis) by blocking B-cell activation and signaling.

Zanubrutinib (BRUKINSA®) is an irreversible, potent, next-generation, small molecule inhibitor of Bruton’s Tyrosine Kinase, designed to deliver targeted and sustained inhibition of the BTK protein by optimizing bioavailability, half-life, and selectivity, while minimizing off-target inhibition of TEC- and EGFR-family kinases. It has been hypothesized that the increased selectivity of BRUKINSA® may minimize toxicities, (such as those often associated with Ibrutinib (IMBRUVICA®) and improve efficacy outcomes. BRUKINSA® demonstrated promising efficacy among patients with CLL/SLL (Small Lymphocytic Lymphoma), in early phase trials.

SEQUOIA is a randomized, multicenter, global Phase III trial, designed to evaluate the efficacy and safety of BRUKINSA® compared to Bendamustine plus Rituximab in patients with treatment naïve CLL or SLL. This trial consists of three cohorts:
Cohort 1 (N=479): Patients NOT harboring del(17p) were randomized 1:1 to receive BRUKINSA® (N=241) or Bendamustine plus Rituximab (N=238) until disease progression or unacceptable toxicity. Patients with del(17p) were not randomized to Bendamustine plus Rituximab, as they experience poor clinical outcomes and poor response to chemoimmunotherapy. Data from this group comprise the Primary endpoint
Cohort 2 (N=110): Patients WITH del(17p) received BRUKINSA® as a monotherapy.
Cohort 3 (enrollment ongoing): Patients WITH del(17p) or pathogenic TP53 variant receiving BRUKINSA® in combination with Venetoclax.

Treatment in Cohort 1 consisted of BRUKINSA® 160 mg orally twice daily as 28-day cycles or Bendamustine 90 mg/m2 IV on Days 1 and 2 for six cycles plus Rituximab 375 mg/m2 IV, the day before or on Day 1 of Cycle 1, and 500 mg/m2 IV on Day 1 of Cycles 2-6. Both treatment groups were well balanced, with more than 50% with unmutated IGHV gene and 18% with del(11q) in each group. Eligible patients had untreated CLL or SLL requiring treatment as per International Workshop on CLL criteria, were 65 years or older, or 18 years or older with comorbidities, WITHOUT del(17p), and had an ECOG PS of 0-2. The Primary endpoint of the SEQUOIA trial was Progression Free Survival (PFS) per Independent Review Committee (IRC) assessment in the randomized Cohort 1 group of patients. Secondary endpoints included Overall Response Rates (ORR), Overall Survival (OS) and Safety.

At the interim analysis, with a median follow-up of 26.2 months, BRUKINSA demonstrated superiority in PFS over Bendamustine plus Rituximab. The median PFS was Not Reached in the BRUKINSA® group and was 33.7 months in the Bendamustine plus Rituximab group. The 24-month PFS rate was 85.5% in the BRUKINSA® group, compared to 69.5% in in the Bendamustine plus Rituximab group (HR=0.42; P<0.0001). This PFS benefit was consistently observed across key patient subgroups, including patients with del(11q), unmutated IGHV status, Binet Stage C, and bulky disease.

In a separate non-randomized group of patients in Cohort 2 of SEQUOIA trial, BRUKINSA® monotherapy was evaluated in 110 patients with previously untreated CLL/SLL, WITH 17p deletion. The Overall Response Rate (ORR) per IRC was 88% and the median Duration of Response (DOR) was not reached after a median follow-up of 25.1 months. The 18-month PFS in this group was 90.6%. Across clinical trials of BRUKINSA® the most common adverse events were neutropenia, upper respiratory tract infection, thrombocytopenia, hemorrhage, and musculoskeletal pain. Atrial fibrillation or flutter were reported in 3.7% of patients.

The researchers from this study concluded that BRUKINSA® significantly improved Progression Free Survival compared to Bendamustine plus Rituximab, in patients with untreated CLL and SLL with an acceptable safety profile, like what has been reported in other BRUKINSA® clinical trials, with consistently low rates of atrial fibrillation. They added that BRUKINSA® as a highly selective BTK inhibitor, can potentially provide a chemo-free treatment option for CLL patients.

Zanubrutinib versus bendamustine and rituximab in untreated chronic lymphocytic leukaemia and small lymphocytic lymphoma (SEQUOIA): a randomised, controlled, phase 3 trial. Tam CS, Brown JR, Kahl BS, et al. The Lancet Oncology 2022;23:1031-1043

FDA Approves POLIVY® for Untreated Diffuse Large B-Cell Lymphoma

SUMMARY: The FDA on April 19, 2023, approved Polatuzumab vedotin-piiq (POLIVY®) with a Rituximab product, Cyclophosphamide, Doxorubicin, and Prednisone (R-CHP) for adult patients who have previously untreated Diffuse Large B-Cell Lymphoma (DLBCL), not otherwise specified (NOS), or High-Grade B-Cell Lymphoma (HGBL) and who have an International Prognostic Index (IPI) score of 2 or greater.

The American Cancer Society estimates that in 2023, about 80,550 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,180 individuals will die of this disease. Diffuse Large B-Cell Lymphoma (DLBCL) is the most common of the aggressive Non-Hodgkin lymphomas in the United States, and the incidence has steadily increased 3-4% each year. More than half of patients are 65 or older at the time of diagnosis and the incidence is likely to increase with aging of the American population. The etiology of Diffuse Large B-Cell Lymphoma is unknown. Contributing risk factors include immunosuppression (AIDS, transplantation setting, autoimmune diseases), UltraViolet radiation, pesticides, hair dyes, and diet.

DLBCL is a neoplasm of large B cells and the most common chromosome abnormality involves alterations of the BCL-6 gene at the 3q27 locus, which is critical for germinal center formation. Two major molecular subtypes of DLBCL arising from different genetic mechanisms have been identified, using Gene Expression Profiling: Germinal Center B-cell-like (GCB) and Activated B-Cell-like (ABC). Patients in the GCB subgroup have a higher 5-year survival rate, independent of clinical IPI (International Prognostic Index) risk score, whereas patients in the ABC subgroup have a significantly worse outcome. Regardless, R-CHOP regimen (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone), given every 21 days, for 6 cycles, delivered with curative intent, is the current standard of care for patients of all ages, with newly diagnosed DLBCL, regardless of molecular subtype. Approximately 30-40% of patients experience disease progression or relapse, during the first 2 years and attempts to improve on R-CHOP regimen have not been successful. Maintenance treatment strategy following R-CHOP, to better control the disease, delay disease progression and improve long term survival, have included Autologous Stem Cell Transplantation, maintenance treatment with agents such as oral protein kinase inhibitor Enzastaurin and Everolimus. Outcomes for transplant-ineligible patients with Relapsed/Refractory DLBCL patients remain poor.

CD79b is a B-cell specific surface protein, which is a component of the B-cell receptor and is ubiquitously expressed on the surface of malignant B cells. POLIVY® (Polatuzumab vedotin) is a CD79b-directed Antibody-Drug Conjugate (ADC) with activity against dividing B cells. It consists of three components: 1) the humanized ImmunoGlobulin G1 (IgG1) monoclonal antibody specific for human CD79b; 2) the small molecule anti-mitotic agent MMAE (monomethyl auristatin E) and 3) a protease-cleavable linker that covalently attaches MMAE to the Polatuzumab antibody. Upon binding to CD79b, POLIVY® is internalized, and the linker is cleaved by lysosomal proteases thus enabling intracellular delivery of MMAE. MMAE then binds to microtubules and kills dividing cells by inhibiting cell division and inducing apoptosis. POLIVY® demonstrated efficacy in patients with Relapsed or Refractory DLBCL, resulting in significantly longer Overall Survival when combined with Bendamustine and Rituximab, compared to Bendamustine and Rituximab alone. Based on these finding, the FDA granted accelerated approval to POLIVY® in June 2019.

In a Phase Ib-II study POLIVY® in combination with Rituximab, Cyclophosphamide, Doxorubicin, and Prednisone (pola-R-CHP) resulted in a 89% Overall Response rate and 77% Complete Responses when given as first line therapy, in patients with DLBCL. In this study, Vincristine was excluded from the regimen owing to the risk of overlapping neurotoxicities with POLIVY®. The present POLARIX trial was conducted to evaluate the efficacy and safety of pola-R-CHP as compared with R-CHOP, in patients with previously untreated DLBCL.

The POLARIX is a randomized, double-blind, placebo-controlled, International Phase III trial in which a total of 879 treatment naïve, CD20-positive, intermediate or high-risk DLBCL patients were randomly assigned in a 1:1 ratio to receive 6 cycles of either pola-R-CHP (N=440) or R-CHOP (N=439). Patients on Day 1 of each 21 day cycle, received POLIVY® 1.8 mg/kg IV and a placebo matching Vincristine IV (pola-R-CHP group) or a placebo matching POLIVY® and intravenous Vincristine at a dose of 1.4 mg/m2 (maximum of 2 mg) (R-CHOP group), along with Rituximab 375 mg/m2 IV, Cyclophosphamide 750 mg/m2 IV and Doxorubicin 50 mg/m2 IV. All the patients also received Prednisone 100 mg orally once daily on Days 1-5 of each of the first six cycles. During cycles 7 and 8, patients in both treatment groups received Rituximab monotherapy at 375 mg/m2 IV. The median patient age was 65 years and stratification was based on IPI score and presence or absence of bulky disease, Subtypes of DLBCL were centrally evaluated and were balanced between the two treatment groups. Patients were eligible regardless of the Cell of Origin or the presence of rearrangements in MYC, BCL2, BCL6, or a combination of these. Approximately 84% of patients had de novo DLBCL, NOS and 11% had high grade B-Cell Lymphoma. Patients with known CNS involvement were excluded but CNS prophylaxis with intrathecal chemotherapy was permitted, in accordance with institutional practice guidelines. The use of Granulocyte Colony-Stimulating Factor (G-CSF) was required during the first six cycles of treatment for primary prophylaxis against neutropenia, and consolidative radiotherapy to initial sites of bulky disease or extranodal sites was allowed at the discretion of the investigator. The Primary end point was Progression Free Survival (PFS). Secondary end points included Overall Survival (OS) and Safety.

At a median follow up of 28.2 months, the PFS was significantly higher in the pola-R-CHP group compared to the R-CHOP group. The PFS at 2 years was 76.7% in the pola-R-CHP group versus 70.2% in the R-CHOP group (stratified HR=0.73; P=0.02). Treatment with pola-R-CHP resulted in a risk of disease progression, relapse, or death that was 27% lower, compared to R-CHOP. Patient subgroups that did not show a clear benefit with pola-R-CHP included patients 60 years of age or younger, patients with the Germinal Center B-cell-like subtype of DLBCL, patients who had bulky disease, and patients who had lower IPI scores. Overall Survival at 2 years did not differ significantly between the treatment groups and the researchers attributed the lack of a significant difference between the two groups in Overall Survival, to the availability of new, effective treatments for relapsed or refractory DLBCL, as well as short duration of follow up at the time of this reporting. The safety profile was similar in the two treatment groups.

The authors concluded that among patients with previously untreated intermediate-risk or high-risk DLBCL, the risk of disease progression, relapse, or death was lower among those who received pola-R-CHP than among those who received R-CHOP.

Polatuzumab Vedotin in Previously Untreated Diffuse Large B-Cell Lymphoma. Tilly H, Morschhauser F, Sehn LH, et al. N Engl J Med 2022; 386:351-363.

FDA Approves JAYPIRCA® for Relapsed or Refractory Mantle Cell Lymphoma

SUMMARY: The FDA on January 27, 2023, granted accelerated approval to JAYPIRCA® (Pirtobrutinib) for Relapsed or Refractory Mantle Cell Lymphoma (MCL) after at least two lines of systemic therapy, including a BTK inhibitor.

The American Cancer Society estimates that in 2023, about 80,550 people will be diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,180 individuals will die of this disease. In the US, approximately 3,300 new cases of MCL are diagnosed each year. Mantle Cell Lymphoma is an aggressive B-cell lymphoma and accounts for approximately 6% of all Non Hodgkin Lymphomas in adults, and is associated with a high relapse rate, following dose-intensive therapies. Early and late relapses in patients with MCL have been attributed to persistence of residual disease. Majority of patients with MCL are elderly and are not candidates for aggressive treatment or Autologous Stem Cell Transplantation.

Bruton’s Tyrosine Kinase (BTK) is a member of the Tec family of kinases, downstream of the B-cell receptor, and is predominantly expressed in B-cells. It is a mediator of B-cell receptor signaling in normal and transformed B-cells. BTK inhibitors inhibit cell proliferation and promotes programmed cell death (Apoptosis) by blocking B-cell activation and signaling. BTK is a validated molecular target found across numerous B-cell leukemias and lymphomas including Chronic Lymphocytic Leukemia (CLL), Mantle Cell Lymphoma (MCL), and Waldenstrom Macroglobulinemia (WM). The 3 covalent BTK inhibitors presently approved by the FDA for MCL include IMBRUVICA® (Ibrutinib) approved in 2013, CALQUENCE® (Acalabrutinib) approved in 2017, and BRUKINSA® (Zanubrutinib) approved in 2019. Covalent BTK inhibitors have transformed the treatment landscape of Mantle Cell Lymphoma. Despite the efficacy of covalent BTK inhibitors, treatment failure often occurs through development of resistance or intolerance.

JAYPIRCA® is a highly selective, reversible (non-covalent) Bruton’s Tyrosine Kinase (BTK) inhibitor, developed to reversibly bind BTK, deliver consistently high target coverage regardless of BTK turnover rate, and preserve activity in the presence of the C481 acquired resistance mutations. JAYPIRCA® is 300 times more selective in BTK inhibition versus 98% of other kinases tested in preclinical studies and inhibits both wildtype and C481-mutant BTK with equal low nM potency, and has favorable oral pharmacology. JAYPIRCA® is well tolerated and demonstrated promising efficacy in patients with poor-prognosis B-cell malignancies following prior therapy, including prior covalent BTK inhibitors (Mato et al. Lancet, 2021).

The BRUIN Phase I/II clinical trial is the ongoing first-in-human, global, open-label, multicenter single armstudy, which evaluated the efficacy of JAYPIRCA® in previously treated patients with Mantle Cell Lymphoma (MCL), Chronic Lymphocytic Leukemia (CLL), Small Lymphocytic Lymphoma (SLL), or other Non-Hodgkin Lymphomas (NHL). The trial included a Phase I dose-escalation component in which the daily dosing of JAYPIRCA® between 25 mg and 300 mg was evaluated, a Phase Ib drug combination safety arm, and a Phase II dose-expansion component, in which JAYPIRCA® 200 mg daily, as a part of 28-day cycles, is being evaluated.

The present FDA approval is based on data from a subset of patients with Mantle Cell Lymphoma (N=120) in the BRUIN Phase I/II trial, treated with JAYPIRCA® 200 mg once daily until disease progression or unacceptable toxicity. Patients had received a median of three prior lines of therapy with 93% having two or more prior lines, and all patients received one or more prior lines of therapy containing a covalent BTK inhibitor. The most common prior BTK inhibitors received were Ibrutinib (67%), Acalabrutinib (30%), and Zanubrutinib (8%), and 83% had discontinued their last BTK inhibitor due to refractory or progressive disease. Patients with active Central Nervous System Lymphoma or allogeneic Hematopoietic Stem Cell Transplantation or CAR T-cell therapy within 60 days were excluded. The main efficacy measures were Overall Response Rate (ORR) and Duration of Response (DOR), as assessed by an Independent Review Committee, using 2014 Lugano criteria.

The ORR was 50%, with a Complete Response rate of 13%, and the Partial Response rate was 38%. The Time to Response was 1.8 months. The estimated median Duration of Response was 8.3 months, and the estimated Duration of Response rate at 6 months was 65.3%. The most common adverse reactions in 15% or more of MCL patients were fatigue, musculoskeletal pain, diarrhea, edema, dyspnea, pneumonia, and bruising. Grade 3 or 4 laboratory abnormalities in 10% or more of patients were cytopenias.

It was concluded that JAYPIRCA® offers a new approach to targeting the BTK pathway for Relapsed and Refractory Mantle Cell Lymphoma patients, previously treated with a covalent BTK inhibitor. The researchers added that this approval of JAYPIRCA® represents an important advance for this group of patients who currently have limited treatment options and have a poor prognosis.

Efficacy of Pirtobrutinib in Covalent BTK-Inhibitor Pre-Treated Relapsed / Refractory Mantle Cell Lymphoma: Additional Patients and Extended Follow-up from the Phase 1/2 BRUIN Study. Wang ML, Shah NN, Jurczak W. Presented at the 64th ASH Annual Meeting and Exposition, December 10-13, 2022, New Orleans, Louisiana. Abstract # 4218.

FDA Approves BRUKINSA® for Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma

SUMMARY: The FDA on January 19, 2023, approved BRUKINSA® (Zanubrutinib) for Chronic Lymphocytic Leukemia (CLL) or Small Lymphocytic Lymphoma (SLL). The American Cancer Society estimates that for 2023, about 18,740 new cases of Chronic Lymphocytic Leukemia (CLL) will be diagnosed in the US and 4490 patients will die of the disease. CLL accounts for about one-quarter of the new cases of leukemia. The average age of patients diagnosed with CLL is around 70 years, and is rarely seen in people under age 40, and is extremely rare in children.

Bruton’s Tyrosine Kinase (BTK) is a member of the Tec family of kinases, downstream of the B-cell receptor and is predominantly expressed in B-cells. It is a mediator of B-cell receptor signaling in normal and transformed B-cells. BTK inhibitors inhibit cell proliferation and promotes programmed cell death (Apoptosis) by blocking B-cell activation and signaling.

Zanubrutinib (BRUKINSA®) is an irreversible, potent, next-generation, small molecule inhibitor of Bruton’s Tyrosine Kinase, designed to deliver targeted and sustained inhibition of the BTK protein by optimizing bioavailability, half-life, and selectivity, while minimizing off-target inhibition of TEC- and EGFR-family kinases. It has been hypothesized that the increased selectivity of BRUKINSA® may minimize toxicities, (such as those often associated with Ibrutinib (IMBRUVICA®) and improve efficacy outcomes. BRUKINSA® demonstrated promising efficacy among patients with CLL/SLL (Small Lymphocytic Lymphoma), in early phase trials.

SEQUOIA is a randomized, multicenter, global Phase III trial, designed to evaluate the efficacy and safety of BRUKINSA® compared to Bendamustine plus Rituximab in patients with treatment naïve CLL or SLL. This trial consists of three cohorts:
Cohort 1 (N=479): Patients NOT harboring del(17p) were randomized 1:1 to receive BRUKINSA® (N=241) or Bendamustine plus Rituximab (N=238) until disease progression or unacceptable toxicity. Patients with del(17p) were not randomized to Bendamustine plus Rituximab, as they experience poor clinical outcomes and poor response to chemoimmunotherapy. Data from this group comprise the Primary endpoint
Cohort 2 (N=110): Patients WITH del(17p) received BRUKINSA® as a monotherapy.
Cohort 3 (enrollment ongoing): Patients WITH del(17p) or pathogenic TP53 variant receiving BRUKINSA® in combination with Venetoclax.

Treatment in Cohort 1 consisted of BRUKINSA® 160 mg orally twice daily as 28-day cycles or Bendamustine 90 mg/m2 IV on Days 1 and 2 for six cycles plus Rituximab 375 mg/m2 IV, the day before or on Day 1 of Cycle 1, and 500 mg/m2 IV on Day 1 of Cycles 2-6. Both treatment groups were well balanced, with more than 50% with unmutated IGHV gene and 18% with del(11q) in each group. Eligible patients had untreated CLL or SLL requiring treatment as per International Workshop on CLL criteria, were 65 years or older, or 18 years or older with comorbidities, WITHOUT del(17p), and had an ECOG PS of 0-2. The Primary endpoint of the SEQUOIA trial was Progression Free Survival (PFS) per Independent Review Committee (IRC) assessment in the randomized Cohort 1 group of patients. Secondary endpoints included Overall Response Rates (ORR), Overall Survival (OS) and Safety.

At the interim analysis, with a median follow-up of 26.2 months, BRUKINSA demonstrated superiority in PFS over Bendamustine plus Rituximab. The median PFS was Not Reached in the BRUKINSA® group and was 33.7 months in the Bendamustine plus Rituximab group. The 24-month PFS rate was 85.5% in the BRUKINSA® group, compared to 69.5% in in the Bendamustine plus Rituximab group (HR=0.42; P<0.0001). This PFS benefit was consistently observed across key patient subgroups, including patients with del(11q), unmutated IGHV status, Binet Stage C, and bulky disease.

In a separate non-randomized group of patients in Cohort 2 of SEQUOIA trial, BRUKINSA® monotherapy was evaluated in 110 patients with previously untreated CLL/SLL, WITH 17p deletion. The Overall Response Rate (ORR) per IRC was 88% and the median Duration of Response (DOR) was not reached after a median follow-up of 25.1 months. The 18-month PFS in this group was 90.6%. Across clinical trials of BRUKINSA® the most common adverse events were neutropenia, upper respiratory tract infection, thrombocytopenia, hemorrhage, and musculoskeletal pain. Atrial fibrillation or flutter were reported in 3.7% of patients.

The researchers from this study concluded that BRUKINSA® significantly improved Progression Free Survival compared to Bendamustine plus Rituximab, in patients with untreated CLL and SLL with an acceptable safety profile, like what has been reported in other BRUKINSA® clinical trials, with consistently low rates of atrial fibrillation. They added that BRUKINSA® as a highly selective BTK inhibitor, can potentially provide a chemo-free treatment option for CLL patients.

Zanubrutinib versus bendamustine and rituximab in untreated chronic lymphocytic leukaemia and small lymphocytic lymphoma (SEQUOIA): a randomised, controlled, phase 3 trial. Tam CS, Brown JR, Kahl BS, et al. The Lancet Oncology 2022;23:1031-1043

FDA Approves Bispecific Antibody LUNSUMIO® for Follicular Lymphoma

SUMMARY: The FDA on December 22, 2022, granted accelerated approval to LUNSUMIO® (Mosunetuzumab-axgb), a bispecific CD20-directed CD3 T-cell engager for adult patients with Relapsed or Refractory Follicular Lymphoma (FL) after two or more lines of systemic therapy.

The American Cancer Society estimates that in 2022, about 80,470 people were diagnosed with Non Hodgkin Lymphoma (NHL) in the United States and about 20,250 individuals died of this disease. Indolent Non Hodgkin Lymphomas are mature B cell lymphoproliferative disorders and include Follicular Lymphoma, Nodal Marginal Zone Lymphoma (NMZL), Extranodal Marginal Zone Lymphoma (ENMZL) of Mucosa-Associated Lymphoid Tissue (MALT), Splenic Marginal Zone Lymphoma (SMZL), LymphoPlasmacytic Lymphoma (LPL) and Small Lymphocytic Lymphoma (SLL). Follicular Lymphoma is the most indolent form and second most common form of all NHLs and they are a heterogeneous group of lymphoproliferative malignancies. Approximately 22% of all NHLs are Follicular Lymphomas (FL).

Advanced stage indolent NHL is not curable and as such, prolonging Progression Free Survival (PFS) and Overall Survival (OS), while maintaining Quality of Life, have been the goals of treatment intervention. Asymptomatic patients with indolent NHL are generally considered candidates for “watch and wait” approach. Patients with advanced stage symptomatic Follicular Lymphoma are often treated with induction chemoimmunotherapy followed by maintenance RITUXAN® (Rituximab). This can result in a median Progression Free Survival of 6-8 years. However, approximately 30% of the patients will relapse in 3 years, and treatment options are limited for patients with relapses after multiple treatments. Patients with Follicular Lymphomas often experience a relapsing and remitting pattern of disease and may be exposed to multiple lines of therapy over the course of their disease. In spite of the availability of multiple systemic therapies for Follicular Lymphoma, the efficacy of these regimens drops off rapidly with later lines of therapy. Novel therapies are therefore being investigated to improve outcomes.

LUNSUMIO® is a first-in-class CD20 x CD3 T-cell engaging bispecific antibody designed to target CD20 on the surface of B cells and CD3 on the surface of T cells. This dual targeting activates and redirects a patient’s existing T cells to engage and eliminate target B cells by releasing cytotoxic proteins into the B cells.

This FDA approval was based on the positive results from the Phase II GO29781 study, which is a multicenter, open-label, dose-escalation and dose-expansion trial evaluating the safety, efficacy, and pharmacokinetics of LUNSUMIO® in patients with heavily pretreated Follicular Lymphoma, including those who were at high risk of disease progression or whose disease was refractory to prior therapies. The efficacy population consisted of 90 enrolled patients with Relapsed or Refractory FL (Grade 1-3a) who had received at least two prior lines of systemic therapy, including an anti-CD20 monoclonal antibody and an alkylating agent.

LUNSUMIO® was administered IV in 21-day cycles with Cycle 1 step-up dosing of 1 mg on Cycle 1, Day 1, 2 mg on Cycle 1 Day 8, 60 mg on Cycle 1 Day 15, 60 mg on Cycle 2 Day 1, and 30 mg on Day 1 in subsequent cycles. Patients with a Complete Response discontinued therapy after 8 cycles. Patients with a Partial Response or Stable disease continued treatment for up to 17 cycles unless they experienced progressive disease or unacceptable toxicity. The Primary endpoint was Objective Response Rate (ORR) assessed by an Independent Review Committee according to standard criteria for Non-Hodgkins Lymphoma.

The ORR was seen in 80% of patients treated with LUNSUMIO® with 60% achieving Complete Responses. A majority of patients (57%) maintained responses for at least 18 months. With a median follow up of 14.9 months among responders, the estimated median Duration of Response was 22.8 months and the estimated Duration of Response at 12 months and 18 months was 62% and 57%, respectively. Among 218 patients with hematologic malignancies who received LUNSUMIO® at the recommended dose, the most common Adverse Event was Cytokine Release Syndrome (CRS) seen in 39% of patients, which can be severe and life-threatening. The median duration of CRS events was 3 days. Other common Adverse Events included fatigue, rash, fever and headache.

It was concluded from this study that in patients with heavily pretreated Follicular Lymphoma, chemotherapy-free, fixed-duration treatment with LUNSUMIO® induced high rates of Complete Remissions with favorable safety profile, allowing potential administration as an outpatient regimen.

Safety and efficacy of mosunetuzumab, a bispecific antibody, in patients with relapsed or refractory follicular lymphoma: a single-arm, multicentre, phase 2 study. Budde LE, Sehn LH, Matasar M, et al. The Lancet Oncology 2022; 23:1055-1065.