Contributions
Abstract: EP371
Type: E-Poster Presentation
Session title: Acute lymphoblastic leukemia - Clinical
Background
Inotuzumab ozogamicin (InO) is a CD-22 directed antibody-drug conjugate indicated for the treatment of relapsed or refractory B-cell acute lymphoblastic leukaemia (R/R ALL). In the randomised phase 3 INO-VATE study (Kantarjian 2016), InO demonstrated increased efficacy compared to conventional chemotherapy. We sought to evaluate the safety and efficacy of InO in the Real-World setting.
Aims
We aimed to characterise patients with R/R ALL initiated on InO in the UK, and evaluate disease response, survival, and occurrence of adverse events, including the risk of veno-occlusive disease / sinusoidal obstruction syndrome (VOD/SOS).
Methods
We conducted a retrospective chart review of 19 adult patients diagnosed with R/R ALL and initiated on InO at 3 centres across the UK between 1st June 2016 and 31st December 2020 (interim analysis, data from 9 patients from an additional site to be added to the poster). The study received ethics approval prior to study set up and data collection. All data was extracted by the patients’ medical team in pseudonymised format prior to data analysis, therefore informed consent was not required.
Results
In total, 10/19 (53%) patients were Females, median age at initiation of InO was 50.8 (range 22.7–85.1) years, and median time since ALL diagnosis was 8.5 (1.3–30.5) months.
At initiation of InO, 17/19 (89%,) patients were experiencing their first relapse. 2/19 (11%) patients were BCR-ABL positive.
At the time of InO treatment initiation, 3/19 (16%) patients had previously received blinatumomab, and 6/19 (32%) patients had undergone a prior haematopoietic stem-cell transplant (HSCT).
After InO discontinuation, 4/19 (21%) patients underwent HSCT, and all received 2 cycles of InO; whilst in the remaining 15 patients, the number of cycles ranged from 1 to 6 (median 3). Among the 4 patients who underwent HSCT, 1 experienced VOD/SOS. Of the 15 patients not proceeding to HSCT, 1 patient experienced VOD/SOS, and subsequently died of this complication. This gave an overall incidence of VOD/SOS of 11%. Additionally, 2/19 (11%) patients experienced a grade 3/4 treatment related adverse event, and 1/19 (5%) patient had abnormal liver function tests not due to VOD/SOS.
After InO discontinuation, in the 16 patients who had available response data, 12 (75%) patients achieved CR/CRi. Of 10 evaluable complete responders, 9 (90%), achieved minimal residual disease (MRD) negativity (8 by flow cytometry and 1 by molecular assessment at a level of 10-4).
At last contact, patients had a median overall survival of 9.4 months (range: 0.1 -37.2). In total, 13/19 (68%) patients were known to be alive at 6 months after InO initiation, and 7/19 (37%) patients at 12 months. All 6/19 (32%) patients who were still alive at the time of data collection had achieved CR with a median follow-up of 14.6 months.
Conclusion
In this sample of UK patients, InO was an effective treatment for patients with R/R B-cell ALL. Response rates, MRD negativity and safety profile were broadly consistent with the established profile of InO in the published phase 3 INO-VATE study.
Reference: Kantarjian HM, et al. N Engl J Med 2016;375:740–753.
Keyword(s): Leukemia, Refractory, Relapsed acute lymphoblastic leukemia, Safety
Abstract: EP371
Type: E-Poster Presentation
Session title: Acute lymphoblastic leukemia - Clinical
Background
Inotuzumab ozogamicin (InO) is a CD-22 directed antibody-drug conjugate indicated for the treatment of relapsed or refractory B-cell acute lymphoblastic leukaemia (R/R ALL). In the randomised phase 3 INO-VATE study (Kantarjian 2016), InO demonstrated increased efficacy compared to conventional chemotherapy. We sought to evaluate the safety and efficacy of InO in the Real-World setting.
Aims
We aimed to characterise patients with R/R ALL initiated on InO in the UK, and evaluate disease response, survival, and occurrence of adverse events, including the risk of veno-occlusive disease / sinusoidal obstruction syndrome (VOD/SOS).
Methods
We conducted a retrospective chart review of 19 adult patients diagnosed with R/R ALL and initiated on InO at 3 centres across the UK between 1st June 2016 and 31st December 2020 (interim analysis, data from 9 patients from an additional site to be added to the poster). The study received ethics approval prior to study set up and data collection. All data was extracted by the patients’ medical team in pseudonymised format prior to data analysis, therefore informed consent was not required.
Results
In total, 10/19 (53%) patients were Females, median age at initiation of InO was 50.8 (range 22.7–85.1) years, and median time since ALL diagnosis was 8.5 (1.3–30.5) months.
At initiation of InO, 17/19 (89%,) patients were experiencing their first relapse. 2/19 (11%) patients were BCR-ABL positive.
At the time of InO treatment initiation, 3/19 (16%) patients had previously received blinatumomab, and 6/19 (32%) patients had undergone a prior haematopoietic stem-cell transplant (HSCT).
After InO discontinuation, 4/19 (21%) patients underwent HSCT, and all received 2 cycles of InO; whilst in the remaining 15 patients, the number of cycles ranged from 1 to 6 (median 3). Among the 4 patients who underwent HSCT, 1 experienced VOD/SOS. Of the 15 patients not proceeding to HSCT, 1 patient experienced VOD/SOS, and subsequently died of this complication. This gave an overall incidence of VOD/SOS of 11%. Additionally, 2/19 (11%) patients experienced a grade 3/4 treatment related adverse event, and 1/19 (5%) patient had abnormal liver function tests not due to VOD/SOS.
After InO discontinuation, in the 16 patients who had available response data, 12 (75%) patients achieved CR/CRi. Of 10 evaluable complete responders, 9 (90%), achieved minimal residual disease (MRD) negativity (8 by flow cytometry and 1 by molecular assessment at a level of 10-4).
At last contact, patients had a median overall survival of 9.4 months (range: 0.1 -37.2). In total, 13/19 (68%) patients were known to be alive at 6 months after InO initiation, and 7/19 (37%) patients at 12 months. All 6/19 (32%) patients who were still alive at the time of data collection had achieved CR with a median follow-up of 14.6 months.
Conclusion
In this sample of UK patients, InO was an effective treatment for patients with R/R B-cell ALL. Response rates, MRD negativity and safety profile were broadly consistent with the established profile of InO in the published phase 3 INO-VATE study.
Reference: Kantarjian HM, et al. N Engl J Med 2016;375:740–753.
Keyword(s): Leukemia, Refractory, Relapsed acute lymphoblastic leukemia, Safety