Safety and Efficacy Study of Loncastuximab Tesirine + Ibrutinib in Diffuse Large B-Cell or Mantle Cell Lymphoma

Phase 1

Terminated

• Conditions: Diffuse Large B-Cell Lymphoma; Mantle Cell Lymphoma
• Interventions: Drug: Loncastuximab Tesirine; Drug: Ibrutinib

• Registration Number: NCT03684694
• Lead Sponsor: ADC Therapeutics S.A.

Brief Summary

The purpose of this Phase 1/2 study is to evaluate the safety and efficacy of Loncastuximab Tesirine (ADCT-402) in combination with Ibrutinib in participants with Advanced Diffuse Large B-Cell Lymphoma or Mantle Cell Lymphoma.

Detailed Description

The Phase 1 portion of the study will cover the dose escalation portion of the study. This will then be followed by the Phase 2 portion of the study, which will treat participants with the dose of loncastuximab tesirine determined in the Phase 1 portion of the study. The ibrutinib dose of 560 mg daily, will remain the same throughout both phases of the study.

A standard 3+3 dose escalation design will be used for the Phase 1 portion of the study. The dose-limiting toxicity (DLT) period will be the 21 days following the first dose of ibrutinib. The dose escalation cohort will receive loncastuximab tesirine for 2 cycles with concurrent ibrutinib (concomitant therapy) and may then continue ibrutinib therapy up to one year.

The Phase 2 portion of the study will involve 3 cohorts:

* Non-germinal center B-cell diffuse large B-cell lymphoma (Non-GCB DLBCL) cohort

* Germinal center B-cell diffuse large B-cell lymphoma (GCB DLBCL) cohort

* Mantle cell lymphoma (MCL) cohort

Each of the cohorts will be treated with the recommended dose of loncastuximab tesirine determined in the Phase 1 portion of the study.

The study will include a Screening Period (of up to 28 days), a Treatment Period (cycles of 3 to 4 weeks), and a Follow-up Period (approximately every 12 week visits for up to 2 years after treatment discontinuation).

Study Timeline

• Study First Submitted: 2018-09-11
• Study First Submitted QC: 2018-09-24
• Study First Posted: 2018-09-26
• Study Start: 2018-12-01
• Primary Completion: 2022-11-08
• Study Completion: 2022-11-08
• Results First Submitted: 2023-11-21
• Status Verified: 2024-01
• Results First Submitted QC: 2024-01-10
• Last Update Submitted: 2024-01-10
• Results First Posted: 2024-02-06
• Last Update Posted: 2024-02-06

Recruitment & Eligibility

• Status: TERMINATED
• Sex: All
• Target Recruitment: 136

Inclusion Criteria

1. Male or female participant aged 18 years or older

2. Pathologic diagnosis of DLBCL or MCL (For Italy Sites Only: MCL patients are excluded.)

3. Participants with DLBCL must have relapsed or refractory disease and have failed or been intolerant to available standard therapy

4. Participants with MCL must have relapsed or refractory disease and have received at least one prior line of therapy (For Italy Sites Only: This exclusion criterion is not applicable)

5. Participants who have received previous CD19-directed therapy must have a biopsy which shows CD19 expression after completion of the CD19-directed therapy

6. Measurable disease as defined by the 2014 Lugano Classification

7. Availability of formalin-fixed paraffin-embedded (FFPE) tumor tissue block (or minimum 10 freshly cut unstained slides if block is not available)

8. ECOG performance status 0 to 2

9. Screening laboratory values within the following parameters:

   1. Absolute neutrophil count (ANC) ≥1.0 × 103/µL (off growth factors at least 72 hours)
   2. Platelet count ≥75 × 103/µL without transfusion in the past 7 days
   3. Hemoglobin ≥8 g/dL (4.96 mmol/L), transfusion allowed
   4. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma glutamyl transferase (GGT) ≤2.5 × the ULN
   5. Total bilirubin ≤1.5 × ULN (participants with known Gilbert's syndrome may have a total bilirubin up to ≤3 × ULN)
   6. Blood creatinine ≤1.5 × ULN or calculated creatinine clearance ≥60 mL/min by the Cockcroft and Gault equation

10. Negative beta-human chorionic gonadotropin (β-HCG) pregnancy test within 7 days prior to start of study drugs on C1D1 for women of childbearing potential

11. Women of childbearing potential must agree to use a highly effective method of contraception from the time of giving informed consent until at least 9 months after the last dose of loncastuximab tesirine or 1 month after last dose of ibrutinib, whichever comes last. Men with female partners who are of childbearing potential must agree that they will use a highly effective method of contraception from the time of giving informed consent until at least 6 months after the participant receives his last dose of loncastuximab tesirine or 3 months after last dose of ibrutinib, whichever comes last

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Exclusion Criteria

1. Known history of hypersensitivity to or positive serum human anti-drug antibody (ADA) to a CD19 antibody
2. Known history of hypersensitivity to ibrutinib
3. Previous therapy with ibrutinib or other BTK inhibitors
4. Previous therapy with loncastuximab tesirine
5. Requires treatment or prophylaxis with a moderate or strong cytochrome P450 (CYP) 3A inhibitor
6. Allogenic or autologous transplant within 60 days prior to start of study drugs (C1D1)
7. Active graft-versus-host disease
8. Post-transplantation lymphoproliferative disorder
9. Active autoimmune disease, including motor neuropathy considered of autoimmune origin and other central nervous system (CNS) autoimmune disease
10. Known seropositive and requiring anti-viral therapy for human immunodeficiency (HIV) virus, hepatitis B virus (HBV), or hepatitis C virus (HCV).
11. History of Stevens-Johnson syndrome or toxic epidermal necrolysis
12. Lymphoma with active CNS involvement at the time of screening, including leptomeningeal disease
13. Clinically significant third space fluid accumulation (i.e., ascites requiring drainage or pleural effusion that is either requiring drainage or associated with shortness of breath)
14. Breastfeeding or pregnant
15. Significant medical comorbidities, including but not limited to, uncontrolled hypertension (blood pressure [BP] ≥160/100 millimeters of mercury (mmHg) repeatedly), unstable angina, congestive heart failure (greater than New York Heart Association class II), electrocardiographic evidence of acute ischemia, coronary angioplasty or myocardial infarction within 6 months prior to screening, uncontrolled atrial or ventricular cardiac arrhythmia, poorly controlled diabetes mellitus, or severe chronic pulmonary disease, or tuberculosis infection (tuberculosis screening based on local standards).
16. Major surgery, radiotherapy, chemotherapy, or other anti-neoplastic therapy within 14 days prior to start of study drugs (C1D1), except shorter if approved by the Sponsor
17. Use of any other experimental medication within 14 days prior to start of study drugs (C1D1)
18. Planned live vaccine administration after starting study drugs (C1D1)
19. Any condition that could interfere with the absorption or metabolism of ibrutinib including malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel
20. Inherited or acquired bleeding disorders
21. Ongoing anticoagulation treatment, except for low-dose heparinisation or equivalent
22. Failure to recover to Grade ≤1 (Common Terminology Criteria for Adverse Events [CTCAE] version 4.0) from acute non-hematologic toxicity (Grade ≤2 neuropathy or alopecia) due to previous therapy prior to screening
23. Congenital long QT syndrome or a corrected QTcF interval of >480 ms at screening (unless secondary to pacemaker or bundle branch block)
24. Active second primary malignancy other than non-melanoma skin cancers, non metastatic prostate cancer, in situ cervical cancer, ductal or lobular carcinoma in situ of the breast, or other malignancy that the Sponsor's medical monitor and Investigator agree, and document should not be exclusionary
25. Any other significant medical illness, abnormality, or condition that would, in the Investigator's judgement, make the participant inappropriate for study participation or put the participant at risk

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Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SEQUENTIAL

Arm && Interventions

Group	Intervention	Description
Phase 1: Dose-Escalation of ADCT-402	Loncastuximab Tesirine	A standard 3+3 dose escalation design will be used. The dose-limiting toxicity (DLT) period will be the 21 days following the first dose of ibrutinib. The dose escalation cohort will receive loncastuximab tesirine for Cycle 1 and 2 (3 weeks each) with concurrent ibrutinib (concomitant therapy) daily. Participants may continue to receive ibrutinib therapy up to 1 year after Cycle 1 Day 1 (once every 4 weeks from Cycle 3 onwards). Loncastuximab tesirine will be administered intravenously (IV).
Phase 1: Dose-Escalation of ADCT-402	Ibrutinib	A standard 3+3 dose escalation design will be used. The dose-limiting toxicity (DLT) period will be the 21 days following the first dose of ibrutinib. The dose escalation cohort will receive loncastuximab tesirine for Cycle 1 and 2 (3 weeks each) with concurrent ibrutinib (concomitant therapy) daily. Participants may continue to receive ibrutinib therapy up to 1 year after Cycle 1 Day 1 (once every 4 weeks from Cycle 3 onwards). Loncastuximab tesirine will be administered intravenously (IV).
Phase 2: MTD or RP2D of ADCT-402 in Non-GCB DLBCL	Loncastuximab Tesirine	Participants with non-germinal center B-cell diffuse large B-cell lymphoma (Non-GCB DLBCL) will receive the maximum tolerated dose (MTD) or recommended Phase 2 dose (RP2D) of loncastuximab tesirine, as determined in Phase 1, once every 3 weeks for Cycle 1 and 2 and a daily dose of ibrutinib. Participants can continue treatment up to 1 year (once every 4 weeks from Cycle 3 onwards). Loncastuximab tesirine will be administered IV.
Phase 2: MTD or RP2D of ADCT-402 in GCB DLBCL	Ibrutinib	Participants with germinal center B-cell diffuse large B-cell lymphoma (GCB DLBCL) will receive the maximum tolerated dose (MTD) or recommended Phase 2 dose (RP2D) of loncastuximab tesirine, as determined in Phase 1, once every 3 weeks for Cycle 1 and 2 and a daily dose of ibrutinib. Participants can continue treatment up to 1 year (once every 4 weeks from Cycle 3 onwards). Loncastuximab tesirine will be administered IV.
Phase 2: MTD or RP2D of ADCT-402 in Non-GCB DLBCL	Ibrutinib	Participants with non-germinal center B-cell diffuse large B-cell lymphoma (Non-GCB DLBCL) will receive the maximum tolerated dose (MTD) or recommended Phase 2 dose (RP2D) of loncastuximab tesirine, as determined in Phase 1, once every 3 weeks for Cycle 1 and 2 and a daily dose of ibrutinib. Participants can continue treatment up to 1 year (once every 4 weeks from Cycle 3 onwards). Loncastuximab tesirine will be administered IV.
Phase 2: MTD or RP2D of ADCT-402 in GCB DLBCL	Loncastuximab Tesirine	Participants with germinal center B-cell diffuse large B-cell lymphoma (GCB DLBCL) will receive the maximum tolerated dose (MTD) or recommended Phase 2 dose (RP2D) of loncastuximab tesirine, as determined in Phase 1, once every 3 weeks for Cycle 1 and 2 and a daily dose of ibrutinib. Participants can continue treatment up to 1 year (once every 4 weeks from Cycle 3 onwards). Loncastuximab tesirine will be administered IV.
Phase 2: MTD or RP2D of ADCT-402 in MCL	Ibrutinib	Participants with mantle cell lymphoma (MCL) will receive the maximum tolerated dose (MTD) or recommended Phase 2 dose (RP2D) of loncastuximab tesirine, as determined in Phase 1, once every 3 weeks for Cycle 1 and 2 and a daily dose of ibrutinib. Participants can continue treatment up to 1 year (once every 4 weeks from Cycle 3 onwards). Loncastuximab tesirine will be administered IV.
Phase 2: MTD or RP2D of ADCT-402 in MCL	Loncastuximab Tesirine	Participants with mantle cell lymphoma (MCL) will receive the maximum tolerated dose (MTD) or recommended Phase 2 dose (RP2D) of loncastuximab tesirine, as determined in Phase 1, once every 3 weeks for Cycle 1 and 2 and a daily dose of ibrutinib. Participants can continue treatment up to 1 year (once every 4 weeks from Cycle 3 onwards). Loncastuximab tesirine will be administered IV.

Primary Outcome Measures

Name	Time	Method
Phase 1: Number of Participants With Serious TEAEs	Day 1 until 30 days after last dose; max duration of treatment was 686 days for Phase 1 (up to approximately 716 days total)	A serious TEAE was defined as any AE which occurred after the first dose of study drug that resulted in death, was life threatening, required inpatient hospitalization or prolongation of existing hospitalization (hospitalization for elective procedures or for protocol compliance was not considered a serious adverse event), resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, or important medical events that did not meet the preceding criteria but based on appropriate medical judgement may have jeopardized the participant or may have required medical or surgical intervention to prevent any of the outcomes listed above.
Phase 1: Number of Participants With Dose Interruptions	Up to a maximum of 686 days
Phase 1: Number of Participants With Dose Reductions	Up to a maximum of 686 days
Phase 2: Complete Response Rate (CRR)	Up to approximately 38 months	CRR according to the 2014 Lugano classifications determined by Independent Review Committee (IRC). CRR was defined as the percentage of participants with a best overall response (BOR) of complete response (CR).
Phase 1: Number of Participants With Treatment-emergent Adverse Events (TEAEs)	Day 1 until 30 days after last dose; max duration of treatment was 686 days for Phase 1 (up to approximately 716 days total)	A TEAE was defined as an adverse event (AE) that occurred or worsened in the period extending from the first dose of study drug to 30 days after the last dose of study drug in this study or start of a new anticancer therapy, whichever is earlier. Any clinically significant changes form baseline in safety laboratory values, vital signs, Eastern Cooperative Oncology Group (ECOG) performance status, and 12-lead electrocardiograms (ECGs) which occurred after first dose of study drug were recorded as TEAEs.
Phase 1: Number of Participants With Dose-Limiting Toxicities (DLTs)	21 days	A DLT was defined as any of the following events which occur during the DLT Period (first 21 days of ibrutinib treatment), except those that are clearly due to underlying disease or extraneous causes: a hematologic DLT (grade ≥3 anaemia, grade 4/febrile neutropenia, grade ≥3 thrombocytopenia), a non-hematologic DLT (including aspartate aminotransferase \[AST\] and/or alanine aminotransferase \[ALT\] \>3× upper limit of normal (ULN) and bilirubin \>2× ULN), any other non-hematologic toxicities ≥ Grade 3, with exceptions.

Secondary Outcome Measures

Name	Time	Method
Phase 1: Overall Response Rate (ORR)	Up to approximately 38 months	ORR according to the 2014 Lugano classification, defined as the percentage of participants with a BOR of CR or partial response (PR).
Phase 1 and Phase 2: Duration of Response (DOR)	Up to approximately 36 months	DOR was defined as the time from the first documentation of tumor response to disease progression or death.
Phase 1 and Phase 2: Relapse-Free Survival (RFS)	Up to approximately 36 months	RFS was defined as the time from the documentation of CR to disease progression or death.
Phase 1 and Phase 2: Area Under the Concentration-Time Curve From Time Zero to the Last Quantifiable Concentration (AUClast) of Loncastuximab Tesirine (Total Antibody, PBD-Conjugated Antibody and Unconjugated Cytotoxin SG3199)	C1D1 pre-dose, EOI, 4h PD, C1D8 168h PD, C1D15 336h PD, C2D1 pre-dose, EOI, 4h PD, C2D8 168h PD, C2D15 336h PD (3 week cycles)	Blood samples were collected for analysis of PK data of loncastuximab tesirine (total antibody, PBD-conjugated antibody and unconjugated cytotoxin SG3199)
Phase 1 and Phase 2: Area Under the Concentration-Time Curve From Time Zero to the End of the Dosing Interval (AUCtau) of Loncastuximab Tesirine (Total Antibody, PBD-Conjugated Antibody and Unconjugated Cytotoxin SG3199)	C1D1 pre-dose, EOI, 4h PD, C1D8 168h PD, C1D15 336h PD, C2D1 pre-dose, EOI, 4h PD, C2D8 168h PD, C2D15 336h PD (3 week cycles)	Blood samples were collected for analysis of PK data of loncastuximab tesirine (total antibody, PBD-conjugated antibody and unconjugated cytotoxin SG3199).
Phase 1 and Phase 2: Area Under the Concentration-Time Curve From Time Zero to Infinity (AUCinf) of Loncastuximab Tesirine (Total Antibody, PBD-Conjugated Antibody and Unconjugated Cytotoxin SG3199)	C1D1 pre-dose, EOI, 4h PD, C1D8 168h PD, C1D15 336h PD, C2D1 pre-dose, EOI, 4h PD, C2D8 168h PD, C2D15 336h PD (3 week cycles)	Blood samples were collected for analysis of PK data of loncastuximab tesirine (total antibody, PBD-conjugated antibody and unconjugated cytotoxin SG3199).
Phase 1 and Phase 2: Clearance (CL) of Loncastuximab Tesirine (Total Antibody, PBD-Conjugated Antibody and Unconjugated Cytotoxin SG3199)	C1D1 pre-dose, EOI, 4h PD, C1D8 168h PD, C1D15 336h PD, C2D1 pre-dose, EOI, 4h PD, C2D8 168h PD, C2D15 336h PD (3 week cycles)	Blood samples were collected for analysis of PK data of loncastuximab tesirine (total antibody, PBD-conjugated antibody and unconjugated cytotoxin SG3199).
Phase 1 and Phase 2: Progression-Free Survival (PFS)	Up to approximately 37 months	PFS was defined as the time between start of treatment and the first documentation of progression, or death.
Phase 1 and Phase 2: Overall Survival (OS)	Up to approximately 38 months	OS was defined as the time between the start of treatment and death from any cause.
Phase 1 and Phase 2: Time to Reach Maximum Concentration (Tmax) of Loncastuximab Tesirine (Total Antibody, PBD-Conjugated Antibody and Unconjugated Cytotoxin SG3199)	C1D1 pre-dose, EOI, 4h PD, C1D8 168h PD, C1D15 336h PD, C2D1 pre-dose, EOI, 4h PD, C2D8 168h PD, C2D15 336h PD (3 week cycles)	Blood samples were collected for analysis of PK data of loncastuximab tesirine (total antibody, PBD-conjugated antibody and unconjugated cytotoxin SG3199)
Phase 1 and Phase 2: Maximum Observed Concentration (Cmax) of Loncastuximab Tesirine (Total Antibody, PBD-Conjugated Antibody and Unconjugated Cytotoxin SG3199)	C1D1 pre-dose, EOI, 4h PD, C1D8 168h PD, C1D15 336h PD, C2D1 pre-dose, EOI, 4h PD, C2D8 168h PD, C2D15 336h PD (3 week cycles)	Blood samples were collected for analysis of PK data of loncastuximab tesirine (total antibody, PBD-conjugated antibody and unconjugated cytotoxin SG3199)
Phase 1 and Phase 2: Accumulation Index (AI) Loncastuximab Tesirine (Total Antibody, PBD-Conjugated Antibody and Unconjugated Cytotoxin SG3199)	C1D1 pre-dose, EOI, 4h PD, C1D8 168h PD, C1D15 336h PD, C2D1 pre-dose, EOI, 4h PD, C2D8 168h PD, C2D15 336h PD (3 week cycles)	Blood samples were collected for analysis of PK data of loncastuximab tesirine (total antibody, PBD-conjugated antibody and unconjugated cytotoxin SG3199).
Phase 1 and Phase 2: Number of Participants With Positive Anti-Drug Antibody (ADA) Titers to Loncastuximab Tesirine at Any Time	Up to a maximum of 711 days	Detection of ADAs was performed by using a screening assay for identification of antibody positive samples/participants, a confirmation assay, and titer assessment.
Phase 2: ORR	Up to approximately 38 months	ORR according to the 2014 Lugano classification, defined as the percentage of participants with a BOR of CR or PR.
Phase 2: CRR in Non-GCB DLBCL, GCB DLBCL, All DLBCL and MCL Participants	Up to approximately 38 months	CRR according to the 2014 Lugano classifications determined by the IRC. CRR was defined as the percentage of participants with a BOR of CR in non-GCB DLBCL, GCB DLBCL, all DLBCL, and MCL participants.
Phase 2: Number of Participants With TEAEs	Day 1 until 30 days after last dose; max duration of treatment was 711 days for Phase 2 (up to approximately 741 days total)	A TEAE was defined as an adverse event (AE) that occurred or worsened in the period extending from the first dose of study drug to 30 days after the last dose of study drug in this study or start of a new anticancer therapy, whichever is earlier. Any clinically significant changes form baseline in safety laboratory values, vital signs, ECOG performance status, and 12-lead ECGs which occurred after first dose of study drug were recorded as TEAEs.
Phase 2: Number of Participants With Serious TEAEs	Day 1 until 30 days after last dose; max duration of treatment was 711 days for Phase 2 (up to approximately 741 days total)	A serious TEAE was defined as any AE which occurred after the first dose of study drug that resulted in death, was life threatening, required inpatient hospitalization or prolongation of existing hospitalization (hospitalization for elective procedures or for protocol compliance was not considered a serious adverse event), resulted in persistent or significant disability/incapacity, was a congenital anomaly/birth defect, or important medical events that did not meet the preceding criteria but based on appropriate medical judgement may have jeopardized the participant or may have required medical or surgical intervention to prevent any of the outcomes listed above.

Trial Locations

Locations (35)

Georgia Cancer Center at Augusta University; 🇺🇸 Augusta, Georgia, United States

The Christie NHS Foundation Trust; 🇬🇧 Manchester, United Kingdom

Centre Hospitalier Lyon Sud; 🇫🇷 Pierre-Bénite, France

Hospital Universitario Marqués de Valdecilla; 🇪🇸 Santander, Spain

Hospital Universitario Vall d'Hebrón; 🇪🇸 Barcelona, Spain

Hospital Duran I Reynals; 🇪🇸 Barcelona, Spain

Azienda Ospedaliera Pap Giovanni XXIII; 🇮🇹 Bergamo, Italy

Istituto Europeo di Oncologia; 🇮🇹 Milano, Italy

Policlinico Sant'Orsola Malpighi; 🇮🇹 Bologna, Italy

Abertawe Bro Morgannwg University Health Board; 🇬🇧 Swansea, United Kingdom

Azienda Socio Sanitaria Territoriale Degli Spedali Civili Di Brescia; 🇮🇹 Brescia, Italy

Azienda Unita Sanitaria Locale de Ravenna; 🇮🇹 Ravenna, Italy

Hospital Universitario Virgen del Rocio; 🇪🇸 Sevilla, Spain

Norton Cancer Institute, St. Matthews Campus; 🇺🇸 Louisville, Kentucky, United States

Centre Hospitalier Universitaire de Rennes Hôpital Pontchailou; 🇫🇷 Bretagne, France

Hôpital Hôtel-Dieu; 🇫🇷 Loiré, France

University of California Irvine Health Chao Family Comprehensive Cancer Center; 🇺🇸 Orange, California, United States

The Blood and Marrow Transplant Group of Georgia; 🇺🇸 Atlanta, Georgia, United States

The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins; 🇺🇸 Baltimore, Maryland, United States

Miami Cancer Institute; 🇺🇸 Miami, Florida, United States

GasthuisZusters Antwerpen Sint-Augustinus; 🇧🇪 Wilrijk, Belgium

Hôpital Saint-Louis; 🇫🇷 Paris, France

University of Michigan Comprehensive Cancer Center; 🇺🇸 Ann Arbor, Michigan, United States

Hôpital Saint-Eloi; 🇫🇷 Montpellier, France

Case Western Reserve University; 🇺🇸 Cleveland, Ohio, United States

Hospital General Universitario Gregorio Marañón; 🇪🇸 Madrid, Spain

University of Minnesota; 🇺🇸 Minneapolis, Minnesota, United States

Redlands Community Hospital; 🇺🇸 Redlands, California, United States

Saint Vincent Healthcare; 🇺🇸 Billings, Montana, United States

Centre Hospitalier Universitaire De Poitier - Hopital De La Miletrie - Hopital Jean Bernard; 🇫🇷 Poitiers, France

IRCCS istituto Clinico Humanitas U.O. di Oncologia ed Ematologia; 🇮🇹 Via Manzoni, Rozzano, Italy

Istituto Scientifico Rmagnolo per lo Studio e la Cura dei Tumori; 🇮🇹 Meldola FC, Italy

Hospital Universitario Fundación Jiménez Díaz; 🇪🇸 Madrid, Spain

University of Miami; 🇺🇸 Miami, Florida, United States

CHU UCL Namur (Site Godinne); 🇧🇪 Yvoir, Belgium