-Author name in bold denotes the presenting author
-Asterisk * with author name denotes a Non-ASH member
Clinically Relevant Abstract denotes an abstract that is clinically relevant.

PhD Trainee denotes that this is a recommended PHD Trainee Session.

Ticketed Session denotes that this is a ticketed session.

1474 First Interim Analysis of the Italian Dante Study: De-Escalation before Treatment-Free Remission in Patients with Chronic Myeloid Leukemia Treated with First-Line Nilotinib

Program: Oral and Poster Abstracts
Session: 632. Chronic Myeloid Leukemia: Clinical and Epidemiological: Poster I
Hematology Disease Topics & Pathways:
Clinical Trials, Clinical Research
Saturday, December 11, 2021, 5:30 PM-7:30 PM

Massimo Breccia, MD1*, Elisabetta Abruzzese, MD2, Fabio Stagno, MD, PhD3, Alessandra Iurlo, MD, PhD4*, Fabrizio Pane, MD5, Immacolata Attolico, MD6*, Paolo Sportoletti, MD7*, Patrizia Pregno8*, Sara Galimberti9*, Barbara Scappini10*, Roberto M. Lemoli, MD11,12, Sergio Siragusa, Prof, MD13, Isabella Capodanno, MD14*, Francesca Chiodi, MD15*, Giuseppe Nicola Saglio, MD, PhD16 and Gianantonio Rosti, MD17*

1Division of Hematology, Department of Translational and Precision Medicine, Azienda Policlinico Umberto I, Sapienza University, Rome, Italy
2Department of Hematology S. Eugenio Hospital, Tor Vergata University, Rome, Italy, Roma, Italy
3Hematology Unit, AOU Policlinico “Rodolico – San Marco” Rodolico Hospital, Catania, Catania, Italy
4Hematology Division, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
5Department of Clinical Medicine and Surgery, Federico II University of Naples, Naples, Italy
6Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology Section, University of Bari, Bari, Italy
7Institute of Hematology and Center of Hemato-Oncology Research (CREO), University of Perugia, Perugia, Italy
8Hematology Unit, Az Ospedaliero Universitaria Città' della Salute e della Scienza, Turin, Italy
9Department of Clinical and Experimental Medicine, Hematology section, University of Pisa, Pisa, Italy
10Hematology Unit, Department of Experimental and Clinical Medicine, Azienda Ospedaliero-Universitaria Careggi, University of Florence, Florence, Italy
11Department of Medicine (DiMI), University of Genoa, Genova, Italy
12IRCCS Policlinico San Martino, Genoa, Italy
13Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (PRO.MI.SE), University of Palermo, Palermo, Italy
14Hematology Unit, Azienda Unità Sanitaria Locale-IRCCS di Reggio Emilia, Reggio Emilia, Italy
15Novartis Farma S.p.A., Origgio, Italy
16Hematology, University of Turin, Turin, Italy
17IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) "Dino Amadori", Meldola, Italy

Introduction: Treatment-free remission (TFR) in chronic myeloid leukemia (CML) is demonstrated to be achievable and recommended for patients (pts) in sustained deep molecular response (sDMR) who can discontinue tyrosine kinase inhibitor (TKI) treatment and maintain responses in ~50% of cases. While the feasibility and safety of TKI cessation have been largely demonstrated, the strategies of TFR optimization are yet to be clarified. Studies (eg. DESTINY) investigating de-escalation, mainly after imatinib, suggested that a stepwise approach may favor TFR outcome. We present the interim results of the phase 2, prospective, multicenter DANTE study (NCT03874858) evaluating de-escalation and TFR in Italian pts with CML in chronic phase (CML-CP) treated with nilotinib (NIL).

Methods: Adults with CML-CP treated with NIL 300 mg twice daily (bid) in first-line for ≥3 years who achieved sDMR for ≥1 year (≥MR 4.0; BCR-ABL level ≤0.01% IS) were enrolled in 27 centers. The study consisted of 4 phases: screening (week [wk] −4-0), consolidation (wk 0-48), TFR (wk 48-144), and follow-up (until wk 144). Ongoing treatment with ≥400 mg/day dose was allowed at study entry. During consolidation, pts were treated with NIL 300 mg once daily (qd). At the end of consolidation phase, pts with sDMR entered TFR phase and discontinued NIL; indeed, pts with at least major molecular response (MMR; BCR-ABL ≤0.1% IS), but without sDMR, continued NIL 300 mg qd. At any time, pts with loss of MMR returned to NIL 300 mg bid.

During TFR phase, BCR-ABL levels were monitored monthly from wk 52-96, and then every 3 months. Pts on half-dose or full-dose NIL were monitored every 3 months. The primary endpoint is the percentage of pts in full treatment-free remission (FTFR) 96 wks after the start of consolidation phase. FTFR is defined as pts with MMR or better, including those who remained in discontinuation during TFR phase and those who are treated with half the standard dose. Key secondary endpoints include percentage of pts with sDMR at wk 48; TFR rate at wk 96 and 144; BCR-ABL kinetics and safety. The predictive role of digital droplet PCR is also evaluated as an exploratory objective.

Results: Overall, 113 pts were screened and 107 entered consolidation phase. This interim analysis included 52 pts who reached the end of consolidation phase by data cut-off period (February 8, 2021). Of these 52 pts, 49 (94.2%) were ongoing by data cut-off and 3 (5.8%) discontinued the study (1 patient due to adverse event (AE) and 2 per patient’s decision). Median age at study entry was 49.5 years. Median time from diagnosis was 5.6 years and median dose of prior NIL treatment was 600 mg/day for all pts except one who was on NIL 450 mg/day at baseline. Median duration of last sustained MR4 and MR4.5 were 30 and 16.5 months, respectively. Further details are listed in Table 1. At screening, molecular response categories were MR4.0 in 13.7%, MR4.5 in 23.1% and undetectable MR4.5 in 63.5% of pts.

During consolidation phase, 5 (9.6%) pts discontinued prematurely: 2 pts restarted NIL full dose (3.8%) for MMR loss, 2 (3.8%) discontinued for AEs and 1 (1.9%) for pt decision. Overall, 47 pts completed consolidation: of them 40 (76.9%) sustained DMR and 7 (13.5%) maintained MMR but not sDMR. Of the 7 pts not sustaining DMR during consolidation, 6 regained DMR after a median of 4.4 months, while 1 pt was still in MMR by data cutoff. The 2 pts who lost MMR after 5 and 8 months regained MMR and 1 regained DMR by data cutoff after increasing NIL to 300 mg bid. Median time spent in consolidation phase was 11.7 months, and the evolution of response categories over time is shown in Figure 1.

During consolidation phase, AEs were observed in 16 pts (30.8%), of them 2 (3.8%) pts had serious AEs: 1 patient had skin ulcers and COVID-19 related pneumonia, while 1 patient had unstable angina. No deaths and disease progressions were observed.

Conclusions: DANTE is the first study that showed the safety and feasibility of NIL de-escalation before TFR in CML-CP pts with sDMR. Interim results suggest that loss of MMR during de-escalation is rare. De-escalation strategy may lead to further improvement of TFR outcome and tolerability and may also preemptively support the identification of pts who may not be ready for discontinuation, with a tailored approach. To date, accuracy in predicting TFR outcome is still low, and the de-escalation setting may sharpen biological and clinical predictive factors, including the potential role of digital PCR.

Disclosures: Breccia: Abbvie: Honoraria; Pfizer: Honoraria; Novartis: Honoraria; Incyte: Honoraria; Bristol Myers Squibb/Celgene: Honoraria. Abruzzese: Incyte: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Bristol Myers Squibb: Consultancy, Honoraria. Stagno: InCyte: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria, Other: Support for attending meetings and/or travel; Novartis: Consultancy, Honoraria, Other: Support for attending meetings and/or travel, Research Funding. Iurlo: Incyte: Speakers Bureau; Novartis: Speakers Bureau; Pfizer: Speakers Bureau; Bristol Myers Squibb: Speakers Bureau. Sportoletti: AstraZeneca: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria. Lemoli: Jazz, Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; AbbVie, Daiichi Sankyo, Servier: Honoraria, Speakers Bureau; Celgene: Other: Support for attending meetings and/or travel. Siragusa: Novartis, CSL, Behring, Amgen, Novonoridsk, SOBI, Bayer: Consultancy, Honoraria, Speakers Bureau. Chiodi: Novartis: Current Employment.

Previous Abstract | Next Abstract >>
*signifies non-member of ASH