A Prospective Randomised, Controlled Trial Switching Sirolimus for Mycophenolate to Enhance Immunological Responses to Third Dose COVID-19 Vaccination in Kidney Transplant Recipients with Poor Baseline Humoral Immunity

Purpose: Kidney transplant recipients (KTR) have inadequate responses to 2-dose COVID vaccination schedules and are at increased risk of severe COVID-19. Formation of T cell memory following vaccination is regulated by mTOR complex 1. mTOR inhibitors have been used in pre-clinical models to boost vaccine-elicited cytotoxic T cell memory responses. In observational studies, KTR receiving mTOR inhibitors had improved serological neutralisation and SARS-CoV-2 reactive T cell responses to 2 doses of COVID-19 vaccine, including cytotoxic T cells and circulating T follicular helper cells. We performed a clinical trial in stable KTR using sirolimus as a substitute for mycophenolate prior to a 3rd dose of COVID-19 vaccine to enhance COVID-19 vaccine responses. Method(s): KTR receiving tacrolimus, mycophenylate and corticosteroid with inadequate response to 2 doses of a COVID vaccine (defined by anti-RBD IgG <100U/ mL) and no history of COVID infection were recruited from 2 Australian transplant centres. Patients were randomised in a 1:1 ratio to continue mycophenolate maintenance or switch to sirolimus (trough level target 6 ng/mL). All patients received a 3rd dose of BNT162b2 COVID-19 vaccine and had immunological responses measured 4-6 weeks later. Result(s): 54 patients were randomised to sirolimus switch (n = 28), or control (n = 26). Patients were 70% male, mean age 57.5 years (SD10.4), with mean graft age 6.2 years (SD 5.4). Mean serum trough concentrations of sirolimus and tacrolimus were 6.4 and 6.1 respectively. There have been no safety or tolerability issues in the sirolimus cohort with stable serum creatinine (mean 117.8 vs 119.3, p=0.6), and mild increase in urinary ACR (mean 5.4 vs 17.4, p=0.1). Final results including immunological testing will be collated March 2022. Conclusion(s): Sirolimus switch is safe and well-tolerated. This trial will determine whether the strategy of mTOR inhibitor therapy peri-vaccination can optimise vaccine immune responses against COVID-19 in KTR.

A PHASE III, RANDOMISED, DOUBLE-BLIND, ACTIVE-CONTROLLED CLINICAL TRIAL to COMPARE BAT1806/BIIB800, A PROPOSED TOCILIZUMAB BIOSIMILAR, with TOCILIZUMAB REFERENCE PRODUCT in SUBJECTS with MODERATE to SEVERE RHEUMATOID ARTHRITIS with AN INADEQUATE RESPONSE to METHOTREXATE THERAPY

Background: BAT1806/BIIB800 is a proposed biosimilar to reference tocili-zumab (TCZ). A Phase III randomised, double-blind, active-controlled clinical trial was conducted as part of a biosimilar development programme. Objectives: To evaluate the efficacy, pharmacokinetics (PK), safety and immu-nogenicity of BAT1806/BIIB800 in comparison with EU-sourced TCZ in subjects with moderate to severe rheumatoid arthritis with inadequate response to meth-otrexate (MTX). Methods: The study was conducted at 55 centres in China and Europe, between June 2018 and January 2021. Eligible subjects were randomised in a 2:1:1 ratio to one of three treatment groups: (1) BAT1806/BIIB800 up to Week 48, (2) TCZ up to Week 48, or (3) TCZ up to Week 24, followed by BAT1806/BIIB800 from Week 24 to Week 48, administered intravenously every 4 weeks at a dose of 8mg/kg. The primary endpoint was the proportion of subjects achieving an ACR20 response at timepoints pre-specifed to meet the requirements of different Regulatory Agencies: Week 12, for EMA;Week 24, for FDA and NMPA. Equivalence margins applied to differences in ACR20 response rates in the BAT1806/BIIB800 and TCZ treatment groups were pre-specifed as follows: +/-14.5% for EMA (95% confdence interval (CI));-12.0%,15% for FDA (90% CI);+/-13.6% for NMPA (95% CI). Secondary endpoints included pharmacokinetics, safety and immunogenicity. The ICH E9(R1) estimands framework including intercurrent events (related or unrelated to the COVID19 pandemic) was implemented for the ACR20 evaluation. A logistic regression model including 'region' (China and Eastern Europe) and 'previous biologic or targeted synthetic DMARD use' (Yes/No) as captured in Interactive Web Response System as stratifcation factors was utilised to assess equivalence for the primary endpoint. The difference in response rates was estimated and corresponding confdence intervals were derived to assess equivalence for the primary endpoint. This presents results up to Week 24. Results: In total, 621 subjects were randomised to receive BAT1806/BIIB800 (N=312), TCZ (N=155), or TCZ followed by BAT1806/BIIB800 (N=154). The groups were comparable in terms of baseline demographics and disease characteristics, including age, gender, disease activity and disease duration. The estimated proportions of subjects achieving an ACR20 response in the BAT1806/BIIB800 vs. the TCZ groups, respectively, were 68.97% vs. 64.82% at Week 12 and 69.89% vs. 67.94% at Week 24. The estimated difference between ACR response rates was 4.15% (95% CI-3.63, 11.93) at week 12, and 1.94% (90% CI-4.04, 7.92;95% CI-5.18, 9.07) at Week 24. The CIs for the estimated differences between the treatment groups were within the pre-defned equivalence margins (Figure 1). The treatment groups were comparable in terms of serum trough levels, incidence of TEAEs and ADA/NAb positivity (Table 1). Conclusion: BAT1806/BIIB800 has demonstrated equivalent efficacy at Week 12 and Week 24 and a similar PK, safety and immunogenicity profile as reference tocilizumab up to Week 24.

Subcutaneous nivolumab versus intravenous nivolumab in patients with previously treated, advanced, or metastatic clear cell renal cell carcinoma

Background: Nivolumab (NIVO), a programmed death-1 immune checkpoint inhibitor, has demonstrated clinical efficacy across patients with different tumor types, including clear cell renal cell carcinoma (ccRCC), when administered via IV infusion. As an alternative to IV infusion, subcutaneous (SC) administration alleviates the need for IV ports, thereby lowering the risk of associated complications such as infections and phlebitis. SC formulation also reduces the time for dose preparation and administration, which may decrease overall treatment burden and reduce patient time in the clinic, benefiting patients and healthcare providers and improving overall healthcare resource utilization. SC-administered NIVO consists of NIVO co-formulated with the recombinant human hyaluronidase PH20 enzyme (NIVO + rHuPH20), which aims to increase the dispersion and absorption of NIVO within the SC space. SC NIVO + rHuPH20 was shown to be safe and well tolerated in a phase 1/2 study, warranting further investigation (Lonardi S et al. J Clin Oncol 2021;39(suppl 15):2575). Methods: CheckMate 67T is a multicenter, randomized, open-label, phase 3 study that will evaluate the noninferiority of SC NIVO + rHuPH20 versus IV NIVO in patients with advanced or metastatic ccRCC who have progressed after receiving ≤ 2 prior systemic treatment regimens. Key inclusion criteria are age ≥ 18 years, histologically confirmed advanced or metastatic ccRCC, measurable disease by RECIST v1.1 within 28 days prior to randomization, and a Karnofsky performance status ≥ 70. Key exclusion criteria are untreated symptomatic metastases to the central nervous system, other malignancy, autoimmune diseases, HIV-positive status with AIDS-defining infection within past year or current CD4 count < 350 cells/μL, other serious or uncontrolled disorders including severe, acute SARS-CoV-2 infection, and prior treatment with immune checkpoint inhibitors, other T-cell-targeting antibody drugs, or live attenuated vaccines within 30 days of first study treatment. At least 454 eligible patients will be randomized to receive SC NIVO + rHuPH20 or IV NIVO. The primary objectives are to demonstrate pharmacokinetic (PK) noninferiority of SC NIVO versus IV NIVO, as measured by time-averaged serum concentration over the first 28 days (Cavgd28) and trough serum concentration at steady state (Cminss) (co-primary endpoints). Secondary endpoints include objective response rate by blinded independent central review, additional PK parameters, safety, efficacy, and immunogenicity of SC NIVO and IV NIVO. This study is currently enrolling patients globally.

TALQUETAMAB, A G PROTEIN-COUPLED RECEPTOR FAMILY C GROUP 5 MEMBER D X CD3 BISPECIFIC ANTIBODY, IN PATIENTS WITH RELAPSED/REFRACTORY MULTIPLE MYELOMA (RRMM): UPDATED PHASE 1 RESULTS FROM MONUMENTAL-1

G protein-coupled receptor family C group 5 member D (GPRC5D) has limited expression in healthy human tissue but is highly expressed in malignant plasma cells, making it a promising target for immunotherapy approaches for MM. Talquetamab (JNJ-64407564) is a first-in-class bispecific antibody that binds to both GPRC5D and CD3 receptors to redirect T cells to kill MM cells. Updated and new results of talquetamab at the recommended phase 2 doses (RP2Ds) are reported (NCT03399799). Eligible patients had RRMM or were intolerant to standard therapies. Patients who were previously treated with B-cell maturation antigen (BCMA)-directed therapies were eligible. This analysis focuses on patients who received talquetamab subcutaneously (SC;range: 5.0-800 μg/kg) weekly (QW) or biweekly (Q2W) with step-up dosing. The primary objectives were to identify the RP2D (part 1) and assess talquetamab safety and tolerability at the RP2Ds (part 2). Adverse events (AEs) were graded by CTCAE v4.03;cytokine release syndrome (CRS) was graded per Lee et al 2014 criteria. Responses were investigator-assessed per IMWG criteria. As of July 19, 2021, 95 patients had received SC talquetamab. The original RP2D was 405 μg/kg SC talquetamab QW with step-up doses, and a second RP2D of 800 μg/kg SC talquetamab Q2W with step-up doses was also identified. 30 patients received 405 μg/kg QW (median 61.5 years [range 46-80];63% male;100% triple-class exposed;80% penta-drug exposed;77% triple-class refractory, 20% penta-drug refractory;30% prior BCMA-directed therapy;median follow-up [mF/U]: 7.5 mo [range 0.9-15.2]). 23 patients received 800 μg/kg Q2W (median 60.0 years [range 47-84];48% male;96% triple-class exposed;70% penta-drug exposed;65% triple-class refractory, 22% penta-drug refractory;17% prior BCMA-directed therapy;mF/U: 3.7 mo [range 0.0-12.0]). No treatment discontinuations due to AEs were reported at either RP2Ds. Most common AEs at the 405 μg/kg QW were CRS (73%;1 grade 3 CRS), neutropenia (67%;grade 3/4: 60%), and dysgeusia (60%;grade 2: 29%). Skin-related AEs occurred in 77% of patients and were all grade 1/2 (nail disorders: 30%). Infections occurred in 37% of patients (1 grade 3 COVID-19 pneumonia). Most common AEs at 800 μg/kg Q2W were CRS (78%;all grade 1/2), dry mouth (44%;all grade 1/2), and neutropenia (44%;grade 3/4: 35%). Skin-related AEs occurred in 65% of patients with grade 3 events in 13% (nail disorders: 17%). Infections occurred in 13% of patients (1 grade 3 pneumococcal sepsis). In 30 response-evaluable patients treated at 405 μg/kg QW, the overall response rate (ORR) was 70% (very good partial response or better [≥VGPR]: 57%). In 17 response-evaluable patients treated at 800 μg/ kg Q2W, the ORR was 71% (≥VGPR: 53%). Responses were durable and deepened over time with both RP2Ds (Figure). Median duration of response (DOR) was not reached at either RP2D;6-month DOR rate was 67% (95% CI: 41-84) at 405 μg/kg QW. Serum trough levels of talquetamab were comparable at both RP2Ds. Pharmacodynamic data at both RP2Ds showed peripheral T cell activation and induction of cytokines. SC talquetamab is well tolerated and highly effective at both RP2Ds. Preliminary data suggest that less frequent, higher doses of SC talquetamab do not negatively impact the safety profile. Further evaluation of talquetamab as monotherapy (phase 2;NCT04634552) and in combination with other therapies in patients with RRMM is underway. (Figure Presented) .

Anti-SARS-CoV-2 vaccination and antibody response in patients with inflammatory bowel disease on immune-modifying therapy. prospective single tertiary center study on 602 IBD patients

BACKGROUND AND AIM: Patients with inflammatory bowel disease (IBD) on immune-modifying treatment could be at an increased risk for severe coronavirus disease of 2019 (COVID-19), thus data on the efficacy and safety of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccines are essential. We have conducted a prospective study of IBD patients vaccinated with BNT162b2, CX- 024414 and ChAdOx1 nCoV-19 vaccines. The aim was to evaluate the rate and the magnitude of seroconversion, to assess the effect of different immune-modifying treatment modalities on the magnitude of anti-SARS-CoV-2 IgG antibody levels, and to analyze the impact of anti-SARS-CoV-2 vaccination on the inflammatory biomarkers of IBD. METHODS: The study included 602 IBD patients and 168 immunocompetent health-care workers serving as controls. Serum anti-SARS-CoV-2 IgG antibodies were measured by chemiluminescent microparticle immunoassay before the vaccination, and 8 weeks after the end of vaccination. RESULTS: Of IBD patients, 82.2% were receiving biological treatment: most of them were treated TNF-alpha inhibitors (48.5%) and just under half of them with concomitant thiopurines or methotrexate, followed by vedolizumab (18.6%) and ustekinumab (15.1%). Only 8.1% of patients were on 5-aminosalicylates, and a minority (2.2%) were treatment-free. The post-vaccine seropositivity rate among IBD patients and controls was 97.8% versus 100%. Median anti-SARS-CoV-2 IgG levels were lower among IBD recipients of ChAdOx1 nCoV-19 compared to two other vaccines (p < 0.0001) and to control ChAdOx1 nCoV-19 recipients (p = 0.01). No correlation was found between serum trough levels and anti-SARS-CoV-2 IgG concentrations for any of the biological drugs used. TNFalpha inhibitors with concomitant immunosuppressive treatment but no other treatment modalities were associated with the lower post-vaccination antibody response ( p <0.0001). When evaluating the laboratory activity of IBD by C-reactive protein and fecal calprotectin levels, no significant differences were found before the vaccination and eight weeks after its completion. CONCLUSION: Our findings warrant particular attention to the anti-SARS-CoV-2 vaccination of IBD patients treated with TNFa inhibitors with concomitant immunomodulators and show priority of mRNA vaccines in this specific group of patients.

Updated Phase 1 Results from MonumenTAL-1: First-in-Human Study of Talquetamab, a G Protein-Coupled Receptor Family C Group 5 Member D x CD3 Bispecific Antibody, in Patients with Relapsed/Refractory Multiple Myeloma

Introduction: Despite recent advances in treatment, patients with multiple myeloma (MM) continue to relapse. G protein-coupled receptor family C group 5 member D (GPRC5D) is a promising target for immunotherapy in patients with MM due to its high expression in malignant plasma cells and limited expression in normal human tissue;unlike other antigens targeted by MM therapies, there is no indication that GPRC5D sheds into the periphery. Talquetamab (JNJ-64407564) is a first-in-class bispecific IgG4 antibody that redirects T cells to kill MM cells by binding to both GPRC5D and CD3 receptors. Here we report updated and new results of talquetamab at the recommended phase 2 doses (RP2Ds) from a phase 1 trial in relapsed/refractory MM (RRMM;NCT03399799). Methods: Eligible patients with MM had relapsed or refractory disease or were intolerant to standard therapies;patients previously treated with B-cell maturation antigen (BCMA)-directed therapies were eligible. This analysis focuses on patients who received talquetamab subcutaneously (SC;range 5.0-800 µg/kg) weekly or biweekly. Step-up dosing was used as a patient management strategy to minimize the severity of cytokine release syndrome (CRS). The primary objectives were to identify the RP2D (part 1) and assess talquetamab safety and tolerability at the RP2Ds (part 2). Adverse events (AEs) were graded by CTCAE v4.03 with CRS events graded per Lee et al 2014 criteria. Responses were investigator-assessed per International Myeloma Working Group criteria. Results: As of July 19, 2021, 95 patients have received SC talquetamab. The RP2D was originally identified as a weekly SC dose of 405 µg/kg talquetamab with step-up doses. However, alternative dosing schedules that require less frequent administration continue to be investigated. A biweekly RP2D was also identified as an SC dose of 800 µg/kg talquetamab with step-up doses. 30 patients received the 405 µg/kg weekly dosing schedule (median age: 61.5 years [range 46-80];63% male;100% triple-class exposed;80% penta-drug exposed;77% triple-class refractory, 20% penta-drug refractory;30% prior BCMA-directed therapy;median follow-up: 7.5 mo [range 0.9-15.2]). 23 patients received the 800 µg/kg biweekly dosing schedule (median age: 60.0 years [range 47-84];48% male;96% triple-class exposed;70% penta-drug exposed;65% triple-class refractory, 22% penta-drug refractory;17% prior BCMA-directed therapy;median follow-up 3.7 mo [range 0.0-12.0]). There were no treatment discontinuations due to AEs at either of the RP2Ds. The most common AEs at the 405 µg/kg weekly dose were CRS (73%;1 patient had grade 3 CRS), neutropenia (67%;grade 3/4: 60%), and dysgeusia (60%;grade 2: 29%);skin-related AEs occurred in 77% (all grade 1/2;nail disorders: 30%) of patients, and infections occurred in 37% of patients (1 patient had grade 3 COVID-19 pneumonia). The most common AEs at the 800 µg/kg biweekly dose were CRS (78%;all grade 1/2), dry mouth (44%;all grade 1/2), and neutropenia (44%;grade 3/4: 35%);skin-related AEs occurred in 65% of patients (grade 3: 13%;nail disorders: 17%) and infections occurred in 13% of patients (1 patient had grade 3 pneumococcal sepsis). In 30 response-evaluable patients treated with the 405 µg/kg weekly dose, the overall response rate (ORR) was 70% (very good partial response or better [≥VGPR] rate: 57%). In 17 response-evaluable patients treated with the 800 µg/kg biweekly dose, the ORR was 71% (≥VGPR rate: 53%). Responses were durable and deepened over time in both cohorts (Figure). Median duration of response (DOR) was not reached at either RP2D;the 6-month DOR rate for patients who received the 405 µg/kg weekly dose was 67% [95% CI: 41-84]. Serum trough levels of talquetamab were comparable at both RP2Ds. Consistent with the mechanism of action for talquetamab, pharmacodynamic data from cohorts treated at both dose levels showed peripheral T-cell activation and induction of cytokines. Conclusions: These findings indicate that SC talquetamab is well tolerated and highly effective at both RP2Ds. Preliminary data from the 800 µg/kg biweekly cohorts indicate that less frequent, higher doses of SC talquetamab do not have a negative impact on the previously described safety profile. Further investigation of talquetamab as monotherapy (phase 2;NCT04634552) and in combination with other therapies in patients with RRMM is underway. [Formula presented] Disclosures: Krishnan: MAGENTA: Consultancy;BMS: Consultancy, Current equity holder in publicly-traded company, Speakers Bureau;JANSSEN: Consultancy, Research Funding;City of Hope Cancer Center: Current Employment;REGENERON: Consultancy;SANOFI: Consultancy;GSK: Consultancy;Amgen: Speakers Bureau. Minnema: Celgene: Other: Travel expenses;Alnylam: Consultancy;Cilag: Consultancy;BMS: Consultancy;Janssen: Consultancy;Kite/Gilead: Consultancy. Berdeja: Lilly, Novartis: Research Funding;Abbvie, Acetylon, Amgen: Research Funding;Celularity, CRISPR Therapeutics: Research Funding;EMD Sorono, Genentech: Research Funding;Poseida, Sanofi, Teva: Research Funding;Bluebird bio, BMS, Celgene, CRISPR Therapeutics, Janssen, Kite Pharma, Legend Biotech, SecuraBio, Takeda: Consultancy;GSK, Ichnos Sciences, Incyte: Research Funding. Oriol: Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees;Karyopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees;Oncopeptides: Consultancy, Membership on an entity's Board of Directors or advisory committees;GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees;BMS/Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees;Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. van de Donk: Roche: Consultancy;Takeda: Consultancy;Cellectis: Research Funding;Amgen: Consultancy, Research Funding;Janssen: Consultancy, Research Funding;BMS/Celgene: Consultancy, Honoraria;Novartis /bayer/servier: Consultancy. Rodriguez-Otero: Clínica Universidad de Navarra: Current Employment;Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees;Celgene-BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees;GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees;Pfizer: Consultancy;Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees;Kite: Honoraria, Membership on an entity's Board of Directors or advisory committees;Amgen: Honoraria;Regeneron: Honoraria. Askari: Janssen: Research Funding. Mateos: Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees;Sea-Gen: Honoraria, Membership on an entity's Board of Directors or advisory committees;Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees;Regeneron: Honoraria, Membership on an entity's Board of Directors or advisory committees;Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees;Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees;Celgene - Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees;Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees;Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees;Oncopeptides: Honoraria;Bluebird bio: Honoraria;AbbVie: Honoraria;GSK: Honoraria;Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees;Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees. Costa: BMS: Consultancy, Honoraria, Research Funding;Janssen: Consultancy, Honoraria, Research Funding;Amgen: Consultancy, Honoraria, Research Funding, Speakers Bureau;Karyopharm: Consultancy, Honoraria;Pfizer: Consultancy, Honoraria;Sanofi: Consultancy, Honoraria, Speakers Burea . Verona: Janssen: Current Employment. Ma: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Girgis: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Yang: Janssen: Current Employment. Hilder: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Russell: Janssen: Ended employment in the past 24 months. Goldberg: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Chari: Shattuck Labs: Consultancy, Membership on an entity's Board of Directors or advisory committees;Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding;Millenium/Takeda: Consultancy, Research Funding;Sanofi Genzyme: Consultancy, Membership on an entity's Board of Directors or advisory committees;Karyopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees;BMS/Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding;Antengene: Consultancy, Membership on an entity's Board of Directors or advisory committees;Takeda: Consultancy, Research Funding;Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding;Pharmacyclics: Research Funding;Secura Bio: Consultancy, Membership on an entity's Board of Directors or advisory committees;Oncopeptides: Consultancy, Membership on an entity's Board of Directors or advisory committees;AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees;GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees;Novartis: Consultancy, Research Funding;Genentech: Consultancy, Membership on an entity's Board of Directors or advisorycommittees;Janssen Oncology: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding.