Elzonris (tagraxofusp-erzs)

P1, N=20, Not yet recruiting, University of Kansas Medical Center

In line with results from 13 published cases outside clinical trials in the literature, sustained responses were associated with CR after tagraxofusp treatment and subsequent alloHCT. Our results provide real-world evidence for safety and efficacy of tagraxofusp as first-line treatment for BPDCN.

P2, N=53, Recruiting, Joshua Zeidner | Not yet recruiting --> Recruiting

The successful targeting of CD123 in BPDCN has also encouraged research into a variety of other CD123-positive hematological neoplasms, including acute myeloid leukemia (AML), and informed the development of other novel agents targeting CD123. This review examines the clinical data leading to the development and approval of tagraxofusp in BPDCN, how it is being used in combination to improve outcomes in BPDCN and AML, and its developing role in other hematological malignancies.

No abstract available

P1, N=0, Withdrawn, Jonsson Comprehensive Cancer Center | N=29 --> 0 | Not yet recruiting --> Withdrawn

In addition, we present best practices and real-world insights from clinicians in academic and community settings in the US on how they use tagraxofusp to treat BPDCN. Several case studies illustrate the efficacy of tagraxofusp and discuss its safety profile, as well as the prevention, mitigation, and management of anticipated adverse events.

Ongoing developments with SL-401, IMGN632, CD123 chimeric antigen receptor (CAR) T-cells, and bispecific antibodies (BsAb) show promising advancements. The exploration of combinations such as CD123-targeted immunotherapies with azacitidine and venetoclax is suggested to enhance antineoplastic responses and improve survival rates in BPDCN patients. In conclusion, this multifaceted approach offers hope for more effective and tailored therapeutic interventions against this challenging hematologic malignancy.

P1, N=36, Recruiting, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins | Not yet recruiting --> Recruiting | Phase classification: P1a/1b --> P1

The advent of tagraxofusp has opened a new era of precision oncology in the treatment of BPDCN. Herein, we present an overview of BPDCN biology, its diagnosis, and treatment options, illustrated by clinical cases.

The patient showed resistance to Tagraxofusp and Venetoclax, and he died about 16 months after diagnosis. Considering the predicted effect of the AFF4::IRF1 fusion on IRF1's antitumor effects and immune regulation, and the possibility of its relevance to the aggressive course observed in this case, we propose further evaluation of the clinical significance of this fusion in BPDCN in future cooperative group studies and the consideration of therapeutic strategies aimed at restoring IRF1-dependent antineoplastic effects in such cases.

BPDCN is a rare and challenging entity sharing various typical characteristics of other hematological diseases. Comprehensive diagnostics should be initiated timely to ensure appropriate treatment strategies.

P2, N=53, Not yet recruiting, Joshua Zeidner

Median overall survival and progression-free survival were 14 months (95% CI, 9.5-NA) and 8.5 months (95% CI, 5.1-NA), respectively. In summary, TAG-AZA-VEN shows encouraging safety and activity in high-risk AML, including TP53-mutated disease, supporting further clinical development of TAG combinations.

Therapy prior to allo-HCT included hydroxyurea and TAG + venetoclax + mini-HyperCVAD for 5 cycles. This case report demonstrates a patient experiencing a clinically meaningful benefit with TAG maintenance therapy after allo-HCT. Both prolonged survival and manageable safety, in this case, highlight the feasibility of long-term TAG maintenance post-allo-HCT to control BPDCN.

The role of the JAK/Signal transducer and activator of transcriptions (STAT) pathway in MF has led to the recent approval of three different JAK2 inhibitors (ruxolitinib, pacritinib, and fedratinib) for MF treatment. Our studies showed high sensitivity of MF cell lines to tagraxofusp as a single agent, which is expected given phase 2 results demonstrated clinical efficacy of single-agent tagraxofusp in R/R MF (Yacoub et al. ASH 2021). In addition, synergism was observed in combination with JAK inhibitors.

Moreover, anti-PD1 (nivolumab), anti-PDL1 (pembrolizumab, atezolizumab), anti-CD52 (alemtuzumab), anti-KIR3DL2-CD158k (lacutamab), and anti-CD70 (cusatuzumab) have been tested or are under investigations in phase II trials. In recent years, targeted (biological) therapies have become available also for primary cutaneous T-cell lymphomas (PCTCLs) including anti-CD30 (brentuximab vedotin) in mycosis fungoides, primary cutaneous anaplastic large T-cell lymphoma, lymphomatoid papulosis; anti-CCR4 (mogamulizumab) in Sezary syndrome; anti-CD123 (tagraxofusp) in blastic plasmocytoid cell neoplasm. The expression of these epitopes on neoplastic cells in skin biopsies or blood samples plays a central role in the management of PCTCL patients. This narrative review aims to provide readers with an update on the latest advances in the newest therapeutic options for PCTCLs.

Eight (26%) patients received tagraxofusp, matched unrelated donor was the most common donor type (39%), and fludarabine + busulfan-based conditioning was used in 17 (55%) patients. Post-transplant cyclophosphamide (PTCy) was used for GVHD prophylaxis in 23 (74%) patients... These results demonstrate the safety and efficacy of allo-HCT in BPDCN. Patients undergoing allo-HCT in first remission had significantly better outcomes. Prospective studies are needed to better define the role of allo-HCT in BPDCN.

Treatment of AML with triplet TAG-AZA-VEN is feasible and shows encouraging activity as up-front therapy in adverse risk AML, including in pts with TP53 mutation. These data (OS 14 mo; TP53 mutant OS 9.5 mo) compare favorably to HMA/VEN in ELN adverse risk (OS 12 mo; Lachowiez, BloodAdv 2023) or TP53 mutant AML with poor risk cytogenetics (OS 5.2 mo; Pollyea, CCR 2022), albeit with some differences between populations. No new safety signals were observed.

Regarding first-line treatment, 34 patients (50%) received AML-like regimens [19 underwent anthracycline and cytarabine (3+7 regimen), 4 FLAGIDA, 4 received FLUGA (fludarabine plus low-dose cytarabine), 1 cytarabine alone, and 1 azacitidine alone]; 9 (13%) acute lymphoblastic leukemia-like regimens; 8 patients (12%) were treated with lymphoma–like regimens; 6 (9%) received medication within clinical trial; 2 (3%) compassionate use of Tagraxofusp, and 9 (13%) supportive care only. We found large heterogeneity of therapeutic approaches, low complete remission rates and scarce rates of allogeneic transplant in the front-line. Improvement of outcomes through well-defined treatment protocols and innovative agents are needed for this high unmet need disease.

We identified 818 total patients: 36% (292/818) received tagraxofusp, 60% (494/818) received intensive chemotherapy (HyperCVAD, AML and ALL-like, and CHOP), 3% (22/818) received less intensive chemotherapy (azacytidine, venetoclax, or other mild regimes), 1% received pivekimab (10/818). From our analysis, the OR of attaining CR between tagraxofusp and chemotherapy was not significant and did not answer the question of which modality has a higher chance of CR. Although it is not possible to draw a direct comparison between the pooled single arm trials, the trend of proportions favored tagraxofusp for obtaining both CR (71% vs 64%) and PR (17% vs 8%). While the mortality rate was higher for tagraxofusp compared to intensive chemotherapy (43% vs 30%), the NR rate (~21%) and the allo-HSCT rate (~50%) were similar.

Tagraxofusp was able to effectively eliminate pDCs and blasts to a lesser extent as a single agent. High expression of BCL-2 in blasts supports the consideration of tagraxofusp in combination with venetoclax as an effective combination therapy to eradicate both blasts and pDCs in AML-PDC patient samples.

Standard of care treatments for BPDCN patients are intense chemotherapy or tagraxofusp (Elzonris®)...Pivekimab sunirine was granted orphan drug and Breakthrough Therapy designation and is currently being tested for the treatment of BPDCN patients as monotherapy and, as a triplet therapy in combination with azacitidine and venetoclax for the treatment of AML patients...Pivekimab sunirine is a potent ADC targeting CD123 and is highly efficacious against an aggressive BPDCN cell line model. This finding reinforces the importance of its use for the treatment of BPDCN patients.

Pts with treatment-naïve BPDCN who received TAG achieved durable outcomes with prolonged survival, including those with known CNS involvement. With over 2 yrs of follow-up, median OS was 20 mos with TAG, which compares favorably to chemotherapy's shorter median OS of ~8-14 mos. No new safety signals were observed.

35% of pts were diagnosed after 2018, only 1 patient has received tagraxofusp, a CD123-directed therapy that received FDA approval for previously untreated or relapsed/refractory BPDCN in 2018(Pemmaraju N et al NEJM 2019)...The outcome of ALL-based treatment was superior as compared to AML-based, but relapse rate remained high. Further global collaboration is needed to collect additional data and to identify the best diagnostic and therapeutic approaches for this challenging disease.

P1a/1b, N=36, Not yet recruiting, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins | Trial completion date: Feb 2028 --> Dec 2028 | Trial primary completion date: Aug 2027 --> Dec 2027

The triplet tagraxofusp-azacytidine-venetoclax appears to be of particular interest among these combinations. Nowadays, several ongoing trials are exploring the use of tagraxofusp in different myeloid neoplasms. This review aims to summarize the actual role of tagraxofusp in BPDCN and other CD123-positive myeloid malignancies.

In 2018, the FDA approved tagraxofusp, a firstin-class CD123-targeting therapy for treatment- naïve or relapsed/refractory BPDCN.However, unfit, relapsed, or refractory patients continue to require effective therapeutic strategies. Besides CD123 Targeted therapy; many other modalities are considered e.g. Venetoclax-based therapy, Transplantation and many new potential therapeutic targets under investigation.

Our case series is limited by a small sample size and short follow-up. However, our results provide further support for the use of tagraxofusp as a first-line therapy for BPDCN in a cohort of elderly patients with significant comorbidities.

Because of the disease's rarity the diagnosis and treatment still pose a significant challenge. We present a case of a patient with BPDCN and show clinical and diagnostic characteristics as well as potential treatment regimes.

The null hypothesis will be rejected if 12 or more CRs are observed in 48 subjects. Continuous monitoring for toxicity will be performed.

In this small subgroup, there is evidence that TAG has efficacy in first-line treatment of BPDCN with PCHM. High response rates were observed and consistent in patients with and without PCHM. The safety profile was manageable and predictable; PCHM did not appear to predispose patients to different TRAEs.

P1a/1b, N=36, Not yet recruiting, Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins | Trial completion date: Nov 2027 --> Feb 2028 | Initiation date: May 2023 --> Aug 2023 | Trial primary completion date: May 2027 --> Aug 2027

Capillary leak syndrome is an important adverse effect of tagraxofusp that requires close monitoring. Several clinical trials are underway to study other regimens for the treatment of BPDCN, including IMGN632 (pivekimab sunirine), venetoclax (alone and in combination with hypomethylating agents), CAR-T cells, and bispecific monoclonal antibodies.

BPDCN currently has 1 approved therapy, tagraxofusp (TAG), with a median age of 68, CR/CRc rate of 57% and mOS of 15.8 mos (n=65; Pemmaraju JCO 2022). PVEK demonstrates compelling activity in frontline and R/R BPDCN pts, including durable responses in the R/R setting for pts who received prior TAG. PVEK safety was manageable with primarily low-grade IRRs and edema and no new safety signals were observed. Enrollment continues in the pivotal de novo frontline BPDCN cohort (NCT03386513) Antibody targeting, Monoclonal antibody, Myeloid malignancies