Emicizumab use in females with moderate or mild hemophilia A without factor VIII inhibitors who warrant prophylaxis

Background

Hemophilia A (HA) is predominantly associated with males due to X-linked inheritance. Males and females with HA have shared unmet medical needs, highlighting the necessity for comprehensive care irrespective of sex.

Objectives

This analysis investigated the efficacy and safety of emicizumab prophylaxis in 3 females with HA.

Methods

HAVEN 6 (NCT04158648) is a phase III study of emicizumab in people with non-severe HA without factor (F)VIII inhibitors warranting prophylaxis per investigator assessment, and the study methodology has been reported previously. Female-specific endpoints included menstruation-related quality of life and menstruation heaviness.

Results

HAVEN 6 enrolled 3 females aged ≥18 years and within reproductive age (n = 2 mild HA; n = 1 moderate HA; n = 2 receiving prior FVIII prophylaxis; n = 1 receiving prior episodic FVIII). Participants presented with diverse bleeding phenotypes at baseline: 2 had no bleeds in the 24 weeks prior to enrollment, while 1 had an annualized bleed rate for all bleeds of 208.6. On-study annualized bleed rates for all bleeds were 0, 2.8, and 11.6, respectively. The 2 evaluable participants indicated improved menstruation-related quality of life vs baseline. Two participants experienced 3 grade 1/2 treatment-related adverse events; no new safety signals were identified. All 3 participants preferred emicizumab over their previous treatment and reported a better score for treatment burden and preoccupation domains of the Comprehensive Assessment Tool of Challenges in Hemophilia questionnaire.

Conclusion

Overall, results were consistent with those reported in the male population enrolled in the HAVEN 6 study, suggesting efficacy and a favorable safety profile for emicizumab in females with non-severe HA warranting prophylaxis.

Emicizumab in people with moderate or mild haemophilia A (HAVEN 6): a multicentre, open-label, single-arm, phase 3 study

BACKGROUND

Clinical trial data are scarce for the use of prophylaxis in people with non-severe haemophilia A. The HAVEN 6 study aims to assess safety and efficacy of emicizumab prophylaxis in people with non-severe haemophilia A without factor VIII (FVIII) inhibitors.

METHODS

HAVEN 6 is a multicentre, open-label, single-arm, phase 3 study taking place in 22 specialty clinics and hospitals in Europe, North America, and South Africa. Eligible participants were people of all ages weighing at least 3 kg with a diagnosis of moderate (FVIII activity ≥1%-≤5%) or mild (FVIII >5%-<40%) haemophilia A without FVIII inhibitors requiring prophylaxis as assessed by the treating physician. Participants received subcutaneous emicizumab 3 mg/kg of bodyweight once weekly for 4 weeks, followed by the participant's choice of maintenance dose: 1·5 mg/kg once weekly, 3 mg/kg every 2 weeks, or 6 mg/kg every 4 weeks. Safety was the primary objective of the study. Safety endpoints included adverse events, serious adverse events, and adverse events of special interest including thromboembolic events and thrombotic microangiopathies. The primary efficacy endpoint was the annualised bleed rate for treated bleeds. Analyses were done for participants who received at least one dose of emicizumab. This study is registered with ClinicalTrials.gov, number NCT04158648, and is active but not recruiting.

FINDINGS

Between Feb 10, 2020, and Aug 31, 2021, we assigned 73 people to treatment. 72 participants received at least one dose of emicizumab (51 moderate [71%]; 21 mild [29%]; 69 male [96%]; three female [4%]; and 61 White [85%]). Median age was 23·5 years (IQR 12·0-36·0); median follow-up was 55·6 weeks (IQR 52·3-61·6) weeks. At baseline, 24 participants (33%) had target joints and 37 (51%) were receiving FVIII prophylaxis. 60 participants (83%) had at least one adverse event; the most common adverse events were headache (in 12 participants [17%]), injection-site reaction (12 [17%]), and arthralgia (11 [15%]). 15 (21%) had at least one emicizumab-related adverse event; no adverse events led to treatment withdrawal, modification, or interruption. Eight participants (11%) reported ten serious adverse events in total, none emicizumab-related. There were no deaths or thrombotic microangiopathies. One participant had grade 1 thrombosed haemorrhoids (classified as a thromboembolic event), unrelated to emicizumab. The annualised bleed rate was 0·9 (95% CI 0·55-1·52) for treated bleeds. 48 participants (67%) had no treated bleeds. All-bleed annualised bleed rates were 10·1 (95% CI 6·93-14·76) from 24 weeks pre-study and 2·3 (1·67-3·12) on-study after a median follow-up of 55·6 weeks.

INTERPRETATION

These data show efficacy and a favourable safety profile of emicizumab in people with non-severe haemophilia A without FVIII inhibitors who warrant prophylaxis, confirming emicizumab as a valuable treatment option in this population.

FUNDING

F Hoffmann-La Roche.

A phase III trial evaluating glofitamab in combination with gemcitabine plus oxaliplatin versus rituximab in combination with gemcitabine and oxaliplatin in patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL)

TPS7575

Background: Prognosis is poor for patients with R/R DLBCL, particularly those who are ineligible for autologous stem cell transplant (ASCT) or who relapse after second-line therapy (Gisselbrecht C, et al. Br J Haematol 2018). While chimeric antigen receptor therapies have shown favorable response rates in R/R DLBCL, convenient off-the-shelf options are needed, especially for patients with rapidly progressing disease (Sermer D, et al. Blood Adv 2020). Glofitamab is a full-length, humanized, immunoglobulin G1 bispecific antibody with two regions that bind to CD20 (B cells) and one region that binds to CD3 (T cells). In an ongoing Phase I study in patients with R/R non-Hodgkin lymphoma, glofitamab monotherapy has induced high response rates with a manageable safety profile (NCT03075696; Hutchings M, et al. ASH 2020). Rituximab in combination with gemcitabine and oxaliplatin (R-GemOx) is widely used for patients with R/R DLBCL who are not eligible for ASCT (Mounier N, et al. Haematologica 2013). Methods: GO41944 (NCT04408638) is a Phase III, open-label, randomized trial designed to evaluate the safety and efficacy of glofitamab plus gemcitabine and oxaliplatin (glofit-GemOx) vs R-GemOx in patients with R/R DLBCL. Eligible patients must be aged ≥ 18 years, have histologically confirmed DLBCL (excluding transformed indolent disease, and high-grade B-cell lymphoma (BCL) with MYC and BCL2 and/or BCL6 rearrangements), and have received ≥ 1 prior systemic therapies; patients who have failed only one prior line of therapy must not be eligible for high-dose chemotherapy followed by ASCT. Prior treatment with GemOx, R-GemOx or a CD20xCD3 bispecific antibody is not permitted. Patients are randomized 2:1 to receive up to eight 21-day cycles of either glofit-GemOx (intravenous [IV], followed by up to four cycles of glofitamab monotherapy) or R-GemOx (IV). A single dose of obinutuzumab is administered seven days prior to the first glofitamab administration. Randomization is stratified by number of prior lines of therapy and outcome of last systemic therapy (relapsed vs refractory). The primary objective is overall survival from time of randomization. Secondary efficacy objectives include progression-free survival, complete and overall response rates, duration of response, and time to deterioration in physical functioning and fatigue, and in lymphoma symptoms. Safety objectives comprise rate of adverse events, change from baseline in targeted vital signs and clinical laboratory test results, and tolerability. Pharmacokinetic, immunogenicity and biomarker endpoints will also be explored. The study started on February 17, 2021; an estimated enrollment of 270 patients by the study completion date of March 2022 is anticipated. Clinical trial information: NCT04408638.

Pharmacokinetics and Pharmacodynamics of Emicizumab in Persons with Hemophilia A with Factor VIII Inhibitors: HAVEN 1 Study

Emicizumab, a bispecific monoclonal antibody, bridges activated factor IX (FIXa) and FX, replacing the function of missing FVIIIa to restore effective hemostasis in persons with hemophilia A (PwHA). Here we assess pharmacokinetic (PK) and pharmacodynamic (PD) biomarkers in PwHA with FVIII inhibitors in the Phase III HAVEN 1 study (NCT02622321). Blood samples from 112 PwHA receiving 1.5 mg/kg once-weekly subcutaneous emicizumab were analyzed at central laboratories. Emicizumab concentrations for PK analysis were measured via validated immunoassay. PD effects were assessed using FVIII chromogenic activity assay containing human factors (Hyphen Biophen FVIII:C), and by FXIa-triggered thrombin generation (TG). Activated partial thromboplastin time (aPTT), prothrombin time (PT), antigen levels of FIX and FX, fibrinogen, D-dimer, and prothrombin fragment 1.2 (PF1.2) levels were determined. Emicizumab trough concentrations ≥ 50 µg/mL were maintained throughout the study. FVIII-like activity and TG (peak height) correlated with emicizumab concentrations and remained above 20 U/dL and 100 nM, respectively, with a weekly maintenance dose, theoretically converting persons with severe hemophilia A to a mild disease phenotype. aPTT was normalized at subtherapeutic concentrations of emicizumab. Plasma concentrations of target antigens FIX and FX were not significantly affected by emicizumab treatment; nor were fibrinogen, PT (international normalized ratio), D-dimer, or PF1.2. The PK profile of once-weekly emicizumab in HAVEN 1 provides sustained therapeutic plasma levels, consistent with population PK models. Both the PK profile and the PD and safety biomarkers are consistent with the established efficacy of emicizumab prophylaxis in PwHA with FVIII inhibitors.

MIRROS: a randomized, placebo-controlled, Phase III trial of cytarabine ± idasanutlin in relapsed or refractory acute myeloid leukemia

Patients with refractory or relapsed acute myeloid leukemia (R/R AML) have a poor prognosis, with a high unmet medical need. Idasanutlin is a small-molecule inhibitor of MDM2, a negative regulator of tumor suppressor p53. By preventing the p53–MDM2 interaction, idasanutlin allows for p53 activation, particularly in patients with TP53 wild-type (WT) status. MIRROS (NCT02545283) is a randomized Phase III trial evaluating idasanutlin + cytarabine versus placebo + cytarabine in R/R AML. The primary end point is overall survival in the TP53-WT population. Secondary end points include complete remission rate (cycle 1), overall remission rate (cycle 1) and event-free survival in the TP53-WT population. MIRROS has an innovative design that integrates a stringent interim analysis for futility; continuation criteria were met in mid-2017 and accrual is ongoing.

Trial registration number: NCT02545283

Obinutuzumab or Rituximab Plus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone in Previously Untreated Diffuse Large B-Cell Lymphoma

Purpose Rituximab (R) plus CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) chemotherapy is the standard of care in previously untreated diffuse large B-cell lymphoma (DLBCL). Obinutuzumab (G) is a glycoengineered, type II, anti-CD20 monoclonal antibody. GOYA was a randomized phase III study that compared G-CHOP with R-CHOP in patients with previously untreated advanced-stage DLBCL. Methods Patients (N = 1,418) were randomly assigned to receive eight 21-day cycles of G (n = 706) or R (n = 712), plus six or eight cycles of CHOP. Primary end point was investigator-assessed progression-free survival (PFS). Results After median observation of 29 months, the number of investigator-assessed PFS events was similar between G (201; 28.5%) and R (215; 30.2%), stratified hazard ratio was 0.92 (95% CI, 0.76 to 1.11; P = .39), and 3-year PFS rates were 70% and 67%, respectively. Secondary end points of independently reviewed PFS, other time-to-event end points, and tumor response rates were similar between arms. In exploratory subgroup analyses, patients with germinal-center B cell-like subtype had a better PFS than did patients with activated B cell-like subtype, irrespective of treatment. Frequencies of grade 3 to 5 adverse events (AEs; 73.7% v 64.7%, respectively) and serious AEs (42.6% v 37.6%, respectively) were higher with G-CHOP compared with R-CHOP. Fatal AE frequencies were 5.8% for G-CHOP and 4.3% for R-CHOP. The most common AEs were neutropenia (G-CHOP, 48.3%; R-CHOP, 40.7%), infusion-related reactions (G-CHOP, 36.1%; R-CHOP, 23.5%), nausea (G-CHOP, 29.4%; R-CHOP, 28.3%), and constipation (G-CHOP, 23.4%; R-CHOP, 24.5%). Conclusion G-CHOP did not improve PFS compared with R-CHOP in patients with previously untreated DLBCL. AEs reported with G were consistent with the known safety profile. Biomarker analyses may help define a future role for G in DLBCL.

Pharmacokinetics, safety, and efficacy of subcutaneous versus intravenous rituximab plus chemotherapy as treatment for chronic lymphocytic leukaemia (SAWYER): a phase 1b, open-label, randomised controlled non-inferiority trial

BACKGROUND

Part one of the two-part SAWYER study predicted that subcutaneous rituximab 1600 mg would achieve trough serum concentrations that were non-inferior to those achieved with intravenous rituximab 500 mg/m(2) in patients with chronic lymphocytic leukaemia. In part two of the study, we aimed to confirm the pharmacokinetic non-inferiority of subcutaneous rituximab, and investigate its safety and efficacy.

METHODS

We did this phase 1b, open-label, randomised controlled non-inferiority study at 68 centres in 19 countries in Europe, North America, South America, and Australasia. Patients aged 18 years or older with untreated chronic lymphocytic leukaemia were randomly assigned, via an interactive voice-response system with a permuted block randomisation scheme (block size of ten), to receive subcutaneous rituximab 1600 mg or intravenous rituximab 500 mg/m(2) plus fludarabine and cyclophosphamide every 4 weeks for up to six cycles. In cycle one, all patients received intravenous rituximab 375 mg/m(2). Randomisation was stratified by Binet stage and fludarabine and cyclophosphamide administration route (oral vs intravenous). Study investigators and patients were not masked to group allocation, but allocation was concealed from the statistician, clinical scientist, and clinical pharmacologist. The primary endpoint was trough serum concentration at cycle five, with a non-inferiority margin of 0·8 for the adjusted geometric mean ratio of the subcutaneous to the intravenous dose. We did the primary analysis in patients in the intention-to-treat population with complete pharmacokinetic data (pharmacokinetic population). This trial is registered with ClinicalTrials.gov, number NCT01292603, and is ongoing, although the treatment stage is now complete.

FINDINGS

Between Aug 20, 2012, and June 17, 2013, we randomly assigned 176 patients to receive subcutaneous rituximab (n=88) or intravenous rituximab (n=88); 134 (76%) patients comprised the pharmacokinetic population. As of May 7, 2014, median follow-up was 13·9 months (IQR 11·9-16·0) for patients in the subcutaneous group and 14·1 months (11·6-16·5) for patients in the intravenous group. At cycle five, the geometric mean trough serum concentration in patients given subcutaneous rituximab was non-inferior to that in patients given intravenous rituximab (97·5 μg/mL vs 61·5 μg/mL), with an adjusted geometric mean ratio of 1·53 (90% CI 1·27-1·85). In the safety analysis, the proportion of patients reporting adverse events was similar between the subcutaneous and intravenous groups (all grades: 82 [96%] of 85 patients and 81 [91%] of 89 patients; serious adverse events: 25 [29%] and 29 [33%] patients; grade ≥3: 59 [69%] and 63 [71%] patients, respectively). The most common adverse event of grade 3 or higher was neutropenia (48 [56%] patients in the subcutaneous group and 46 [52%] patients in the intravenous group); the most common serious adverse event was febrile neutropenia (n=9 [11%] and n=4 [4%], respectively). We recorded administration-related reactions in 37 (44%) patients given subcutaneous rituximab and 40 (45%) patients given the intravenous dose, with differences between administration routes for injection-site erythema (n=10 [12%] and n=0, respectively) and nausea (n=2 [2%] and n=11 [12%], respectively). More patients reported local cutaneous reactions after subcutaneous rituximab (n=36 [42%]) than after intravenous rituximab (n=2 [2%]); most of these reactions were grade 1 or 2.

INTERPRETATION

When combined with fludarabine and cyclophosphamide, subcutaneous rituximab 1600 mg achieved trough serum concentrations that were pharmacokinetically non-inferior to those achieved with intravenous rituximab 500 mg/m(2), with a similar safety and efficacy profile between the two groups. Treatment with subcutaneous rituximab should allow patients with chronic lymphocytic leukaemia to receive clinical benefit from the drug via a more convenient delivery method than the intravenous route, and might also be used in combination regimens with approved and emerging oral regimens.

FUNDING

F Hoffmann-La Roche.

Pharmacokinetics and safety of subcutaneous rituximab plus fludarabine and cyclophosphamide for patients with chronic lymphocytic leukaemia

AIMS

The aim of the phase Ib, two part SAWYER study (BO25341; NCT01292603) was to investigate the pharmacokinetics and safety of subcutaneous (s.c.) rituximab compared with intravenous (i.v.) rituximab, both in combination with fludarabine and cyclophosphamide (FC), as first line treatment for patients with chronic lymphocytic leukaemia (CLL).

METHODS

During part 1 (dose-finding), CLL patients received rituximab i.v. followed by a single dose of rituximab s.c. at one of three fixed doses (1400, 1600 or 1870 mg) in cycle 6. The primary objective was to identify a fixed s.c. dose that would achieve comparable rituximab serum trough concentrations (Ctrough ) to those achieved with the standard 4 weekly 500 mg m(-2) rituximab i.v. dose.

RESULTS

Fifty-five patients received a fixed dose of rituximab s.c., 16 received 1400 mg, 17 received 1600 mg and 22 received 1870 mg. The 1600 mg dose was predicted to achieve non-inferior Ctrough to standard rituximab i.v.

TREATMENT

The rituximab s.c. safety profile was comparable with rituximab i.v., except that local administration-related reactions, mainly mild/moderate injection site reactions, occurred more frequently with rituximab s.c., which was not unexpected. Subcutaneous administration was preferred to i.v. administration by >90% of patients and nurses (n = 112).

CONCLUSIONS

SAWYER part 1 data predict that rituximab s.c. 1600 mg will achieve non-inferior Ctrough concentrations to rituximab i.v. 500 mg m(-2) , administered 4 weekly. This fixed s.c. dose is currently undergoing formal non-inferiority assessment in SAWYER part 2. In future, CLL treatment regimens comprising rituximab s.c. and oral FC could substantially reduce i.v. chair time.

Comparison of subcutaneous versus intravenous administration of rituximab as maintenance treatment for follicular lymphoma: results from a two-stage, phase IB study

PURPOSE

This two-stage phase IB study investigated the pharmacokinetics and safety of subcutaneous (SC) versus intravenous (IV) administration of rituximab as maintenance therapy in follicular lymphoma.

PATIENTS AND METHODS

In stage 1 (dose finding), 124 patients who responded to rituximab induction were randomly assigned to SC rituximab (375 mg/m2, 625 mg/m2, or an additional group at 800 mg/m2) or IV rituximab (375 mg/m2). The objective was to determine an SC dose that would yield a rituximab serum trough concentration (Ctrough) in the same range as that of IV rituximab. In stage 2, 154 additional patients were randomly assigned (1:1) to SC rituximab (1,400 mg) or IV rituximab (375 mg/m2) given at 2- or 3-month intervals. The objective was to demonstrate noninferior rituximab Ctrough of SC rituximab relative to IV rituximab 375 mg/m2.

RESULTS

Stage 1 data predicted that a fixed dose of 1,400 mg SC rituximab would result in a serum Ctrough in the range of that of IV rituximab. Noninferiority (ie, meeting the prespecified 90% CI lower limit of 0.8) was then confirmed in stage 2, with geometric mean Ctrough SC:Ctrough IV ratios for the 2- and 3-month regimens of 1.24 (90% CI, 1.02 to 1.51) and 1.12 (90% CI, 0.86 to 1.45), respectively. Overall safety profiles were similar between formulations (in stage 2, 79% of patients experienced one or more adverse events in each group). Local administration-related reactions (mainly mild to moderate) occurred more frequently after SC administration.

CONCLUSION

The fixed dose of 1,400 mg SC rituximab predicted by using stage 1 results was confirmed to have noninferior Ctrough levels relative to IV rituximab 375 mg/m2 dosing during maintenance, with a comparable safety profile. Additional investigation will be required to determine whether the SC route of administration for rituximab provides equivalent efficacy compared with that of IV administration.

First-Line Trastuzumab Plus Epirubicin and Cyclophosphamide Therapy in Patients With Human Epidermal Growth Factor Receptor 2–Positive Metastatic Breast Cancer: Cardiac Safety and Efficacy Data From the Herceptin, Cyclophosphamide, and Epirubicin (HERCULES) Trial

Purpose

A high incidence of congestive heart failure (CHF) has been observed in patients with metastatic breast cancer (MBC) receiving doxorubicin-based chemotherapy and trastuzumab. The Herceptin, Cyclophosphamide, and Epirubicin (HERCULES) trial evaluated trastuzumab plus cyclophosphamide and the less cardiotoxic anthracycline epirubicin.

Patients and Methods

This prospective trial combined a phase I dose-finding stage with a phase II randomized stage. In total, 120 patients with human epidermal growth factor receptor 2 (HER2) –positive MBC and adequate cardiac function received first-line trastuzumab (4 mg/kg intravenous loading dose, then 2 mg/kg every week) plus cyclophosphamide (600 mg/m2) and either epirubicin 60 mg/m2 (HEC-60) or 90 mg/m2 (HEC-90) for six cycles, followed by trastuzumab monotherapy until progression. Sixty patients with HER2-negative disease received epirubicin (90 mg/m2) and cyclophosphamide (EC-90) alone. The primary end point was dose-limiting cardiotoxicity (DLC).

Results

Incidence of DLC was 5.0%, 1.7%, and 0% in the HEC-90, HEC-60, and EC-90 arms, respectively. All DLC events were manageable. There were no cardiac-related deaths. Other adverse-event profiles were comparable across the three arms, except febrile neutropenia, which was reported in 10% of the HEC-90 arm compared with 3% of the other arms. Tumor response rates were 57%, 60%, and 25% in the HEC-60, HEC-90, and EC-90 arms, respectively; median time to progression was 12.5, 10.1, and 7.6 months, respectively.

Conclusion

The HEC regimen is a promising treatment option for patients with HER2-positive MBC. The lower incidence of DLC with HEC, compared with the historic incidence associated with trastuzumab plus doxorubicin, supports further evaluation of the regimen, especially in adjuvant or neoadjuvant settings.

Intensive loading dose of trastuzumab achieves higher-than-steady-state serum concentrations and is well tolerated

PURPOSE Pharmacokinetics (PKs) and safety results from phase II/III trials suggest that, if high trastuzumab serum concentrations are reached early during treatment for human epidermal growth factor receptor 2 (HER2)-positive breast cancer, patients will gain clinical benefit, and the synergistic effects of trastuzumab and chemotherapy will be maximized. This phase I/II study evaluated the PKs, efficacy, and safety of a novel, intensive loading regimen of trastuzumab in women with HER2-positive metastatic breast cancer (MBC). PATIENTS AND METHODS An intensive loading regimen of trastuzumab was given (6 mg/kg intravenously on days 1, 8, and 15 followed by 6 mg/kg every 3 weeks from day 22) to women age 18 years or older with HER2-positive MBC who may have received previous surgery, radiotherapy, and/or chemotherapy. Study medication was continued until disease progression or withdrawal occurred. Results All eligible women (N = 72) received at least one dose of trastuzumab. Median estimated trough concentration of trastuzumab at the end of 3 weeks of the intensive loading regimen (total of 18 mg/kg of trastuzumab administered) of cycle 1 was 119 mg/L, which is higher than steady-state trough concentrations with a conventional weekly or every-3-week regimen (64.9 or 47.3 mg/L, respectively). No new or unexpected adverse events or increased cardiotoxicity were reported during the study. In patients with measurable disease (n = 47), response rate was 23.4%. Median time to progression was 7.7 months (in all patients). CONCLUSION An intensive loading regimen of trastuzumab achieved higher-than-steady-state serum concentrations during cycle 1, was well tolerated, and had a good efficacy profile.