ABSTRACT
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) .
ABSTRACT
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.
ABSTRACT
Background: Multiple myeloma (MM) patients are immunocompromised due to defects in humoral/cellular immunity and immunosuppressive therapy. Reports indicate that the antibody (Ab) response in MM after 1 dose of SARS-CoV-2 RNA vaccine is attenuated. The impact of treatment on cellular immunity after vaccination remains unknown. Methods: We analyzed SARS-CoV-2 spike-binding (anti-S) IgG level in 320 MM patients receiving SARS-CoV-2 RNA vaccination. Blood and saliva were taken at multiple time points and compared with serology data of 69 age-matched vaccinated healthcare workers. We profiled SARS-CoV-2-specific T cell responses in a subset of 45 MM patients and 12 age-matched healthy controls by flow cytometry and ELIspot. All subjects were enrolled in studies approved by the Institutional Review Board at the Icahn School of Medicine at Mount Sinai. Results: The 320 patients (median age 68 year) received two-dose RNA vaccines (69.1% BNT162b2, 27.2% mRNA-1273). Median time to diagnosis was 60 months with a median of 2 prior treatment lines (range 0-16). We included 23 patients with smoldering MM. Patients received various treatments at vaccination with 148 (43.8%) on anti-CD38-containing treatment, 36 (11.3%) on BCMA-targeted therapy and 59 (18.4%) not on active treatment (incl. SMM patients). At the last available evaluation prior to vaccination, 131 (40.9%) exhibited a complete response. At data cutoff, a total of 260 patients (81.3%) had anti-S IgG measured >10 days after the second vaccine (median 51 days). Of these, 84.2% mounted measurable anti-S IgG levels (median 149 AU/mL). In the control group, Ab levels were significantly higher (median 300 AU/mL). Ab levels in the vaccinated MM patients with prior COVID-19 were 10-fold higher than those of patients without prior COVID-19 (p<0.001). Repeat Ab measurements up to 60 days after second vaccination confirm delayed and suboptimal IgG kinetics, particularly in patients receiving anti-MM treatment compared to controls (Figure 1). MM patients on active treatment had lower anti-S IgG levels (p=0.004) compared to patients not on therapy (median 70 vs 183 AU/mL). Notably, 41 patients (15.8%) failed to develop detectable anti-S IgG: 24/41 (58.5%) were on anti-CD38, 13/41 (31.7%) on anti-BCMA bispecific Ab therapy and 4/41 (9.8%) >3 months after CAR T. Univariate analysis showed an association of disease-related factors with absence of anti-S IgG: more previous lines of treatment (>3 lines, p=0.035;>5 lines, p=0.009), receiving active MM treatment (p=0.005), grade 3 lymphopenia (p=0.018), receiving anti-CD38 therapy (p=0.042) and receiving BCMA-targeted therapy (p<0.001). Multivariate analysis (corrected for age, vaccine type, lines of treatment, time since diagnosis, response status and lymphopenia) confirmed that anti-CD38 (p=0.005) and BCMA-targeted treatment (p<0.001) are associated with not developing detectable anti-S IgG. Clinical relevance is emphasized by 10 cases of COVID-19 after 1 (n=7) or 2 vaccine doses (n=3, all without anti-S IgG) with 1 patient passing due to respiratory failure. We studied SARS-CoV-2-specific T cell responses >2 weeks after the second vaccine in 18 MM patients with undetectable anti-S IgG (seronegative), 27 with detectable anti-S IgG (seropositive) and 12 healthy seropositive controls. We found that seropositive MM patients had CD4+CD154+ T cells producing IFNg, TNFa and IL-2 at similar levels as controls, whereas in the seronegative MM cohort CD4 T cell responses were significantly reduced (p<0.005). SARS-CoV-2-specific CD8 T cell responses were overall weaker and not different across cohorts. This data suggests that absence of detectable IgG is associated with suboptimal response of humoral and cellular immunity. Conclusion: MM patients mount a suboptimal IgG response after SARS-CoV-2 vaccination, with 15.8% of patients without detectable anti-S IgG. Ongoing analyses will highlight durability of serological protection against COVID-19. Additional data on T cell responses and immunophenotyping in the context of vaccination will be upda ed at the meeting. Implications are continuation of non-pharmacological interventions, e.g. masking/social distancing, for vulnerable patients. The findings underscore a need for serological monitoring of MM patients after vaccination and for trials assessing use of prophylactic strategies or studies exploring additional immunization strategies. [Formula presented] Disclosures: Wang: Sanofi Genzyme: Consultancy. Chari: Karyopharm: 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;Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees;Pharmacyclics: Research Funding;GlaxoSmithKline: Consultancy, Membership on an entity's Board of Directors or advisory committees;Secura Bio: Consultancy, Membership on an entity's Board of Directors or advisory committees;Amgen: 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;Oncopeptides: Consultancy, Membership on an entity's Board of Directors or advisory committees;Novartis: Consultancy, Research Funding;Janssen Oncology: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding;Shattuck Labs: 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;Takeda: Consultancy, Research Funding;AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees. Cordon-Cardo: Kantaro: Patents & Royalties. Krammer: Kantaro: Patents & Royalties;Merck: Consultancy;Pfizer: Consultancy;Avimex: Consultancy;Seqirus: Consultancy. Jagannath: Legend Biotech: Consultancy;Karyopharm Therapeutics: Consultancy;Janssen Pharmaceuticals: Consultancy;Bristol Myers Squibb: Consultancy;Sanofi: Consultancy;Takeda: Consultancy. Simon: Kantaro: Patents & Royalties. Parekh: Foundation Medicine Inc: Consultancy;Amgen: Research Funding;PFIZER: Research Funding;CELGENE: Research Funding;Karyopharm Inv: Research Funding.