Trial Outcomes & Findings for Study of Bendamustine and Ofatumumab in Elderly Patients With Newly Diagnosed Diffuse Large B-Cell Lymphoma Who Are Poor Candidates for R-CHOP Chemotherapy (NCT NCT01626352)
NCT ID: NCT01626352
Last Updated: 2017-11-22
Results Overview
Disease response assessments will be performed using the International Working Group (IMW)-revised response criteria for malignant lymphoma (Cheson 2007). Complete response requires a disappearance of all evidence of disease.
COMPLETED
PHASE2
22 participants
18 months
2017-11-22
Participant Flow
Between October 2012 to July 2014, 22 subjects with newly diagnosed Diffuse Large B-Cell Lymphoma (DLBCL) were screened for enrollment in the study at 12 investigational sites in the U.S.. Of those, 21 were treated.
Participant milestones
| Measure |
Bendamustine/Ofatumumab
All patients will receive ofatumumab and bendamustine as an intravenous (IV) infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg Days 1 and 8 during Cycle 1 only, and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Overall Study
STARTED
|
22
|
|
Overall Study
COMPLETED
|
12
|
|
Overall Study
NOT COMPLETED
|
10
|
Reasons for withdrawal
| Measure |
Bendamustine/Ofatumumab
All patients will receive ofatumumab and bendamustine as an intravenous (IV) infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg Days 1 and 8 during Cycle 1 only, and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Overall Study
Disease Progression
|
3
|
|
Overall Study
Intercurrent Illness
|
2
|
|
Overall Study
Death
|
2
|
|
Overall Study
Withdrawal by Subject
|
1
|
|
Overall Study
Non-Compliance
|
1
|
|
Overall Study
Never Treated
|
1
|
Baseline Characteristics
Study of Bendamustine and Ofatumumab in Elderly Patients With Newly Diagnosed Diffuse Large B-Cell Lymphoma Who Are Poor Candidates for R-CHOP Chemotherapy
Baseline characteristics by cohort
| Measure |
Bendamustine/Ofatumumab
n=21 Participants
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=5 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
0 Participants
n=5 Participants
|
|
Age, Categorical
>=65 years
|
21 Participants
n=5 Participants
|
|
Age, Continuous
|
83 years
n=5 Participants
|
|
Sex: Female, Male
Female
|
9 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
12 Participants
n=5 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
1 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Black or African American
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
White
|
20 Participants
n=5 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
|
Region of Enrollment
United States
|
21 Participants
n=5 Participants
|
PRIMARY outcome
Timeframe: 18 monthsPopulation: All patients treated with study drugs and having a post baseline response assessment.
Disease response assessments will be performed using the International Working Group (IMW)-revised response criteria for malignant lymphoma (Cheson 2007). Complete response requires a disappearance of all evidence of disease.
Outcome measures
| Measure |
Bendamustine/Ofatumumab
n=21 Participants
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Number of Patients With a Complete Response
|
7 Participants
|
SECONDARY outcome
Timeframe: After cycles 3 and 6 of each 21-day cycle and every 3 months thereafter until disease progression or relapse from complete response for up to 38 monthsPopulation: All patients treated with study drugs and having a post baseline response assessment of a complete or partial response.
Defined as the time from date of first documented confirmed response to date of disease progression or relapse from complete response as defined by the International Working Group (IMW)-revised response criteria for malignant lymphoma (Cheson 2007). This criteria categorizes the response of a patient's tumor to treatment as Complete Response (CR): the disappearance of all disease evidence; Partial Response (PR): regression of measurable disease and no new sites; Stable Disease (SD): less than a PR but not progressive disease (PD); Relapsed Disease or PD: Any new lesion or increase by ≥ 50% of previously involved sites from nadir. Patients who are alive and free from disease progression will be censored at the date of last tumor assessment. Patients who begin further anticancer therapy prior to disease progression will be censored at the date of last tumor assessment prior to the start date of the anticancer therapy.
Outcome measures
| Measure |
Bendamustine/Ofatumumab
n=19 Participants
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Duration of Response
|
5.6 months
Interval 2.9 to 9.8
|
SECONDARY outcome
Timeframe: After cycles 3 and 6 of each 21-day cycle, and every 3 months thereafter until progression or relapse from complete response for up to 40 monthsPopulation: All enrolled patients who have received study treatment.
Defined as the time from date of first treatment to the date of first documented disease progression or relapse from complete response as defined by the International Working Group (IMW)-revised response criteria for malignant lymphoma (Cheson 2007). This criteria categorizes the response of a patient's tumor to treatment as Complete Response (CR): the disappearance of all disease evidence; Partial Response (PR): regression of measurable disease and no new sites; Stable Disease (SD): less than a PR but not progressive disease (PD); Relapsed Disease or PD: Any new lesion or increase by ≥ 50% of previously involved sites from nadir.
Outcome measures
| Measure |
Bendamustine/Ofatumumab
n=21 Participants
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Time to Progression (TTP)
|
10.5 months
Interval 4.5 to
Not reached at this time
|
SECONDARY outcome
Timeframe: every 3 cycles during treatment and every 3 months thereafter until progression or death from any cause, projected 18 monthsPopulation: All enrolled patients who have received study treatment.
Defined as the time from Day 1 of study drug administration to date of death from any cause.
Outcome measures
| Measure |
Bendamustine/Ofatumumab
n=21 Participants
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Overall Survival (OS)
|
12.0 months
Interval 5.9 to 30.8
|
SECONDARY outcome
Timeframe: after cycles 3 and 6 of each 21-day cycle, and every 3 months thereafter, projected 18 monthsPopulation: All patients treated with study drugs and having a post baseline response assessment.
Overall response is the number of patients with observed complete or partial response (CR or PR) as assessed using the International Working Group (IMW) revised response criteria for malignant lymphoma (Cheson 2007). Complete response requires disappearance of all evidence of disease. Partial response requires regression of measurable disease and no new sites.
Outcome measures
| Measure |
Bendamustine/Ofatumumab
n=21 Participants
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Overall Response (OR)
|
19 Participants
|
SECONDARY outcome
Timeframe: after cycles 3 and 6 of each 21-day cycle, and up to 30 days after last dose, projected 24 weeksPopulation: All enrolled patients who received the study treatment.
A treatment-related adverse event was any untoward medical occurrence in a participant which was considered to have a relationship with the study drug (suspected to be possibly or probably related to the study drug per the Investigator's assessment). Adverse events were evaluated using the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v4.0.
Outcome measures
| Measure |
Bendamustine/Ofatumumab
n=21 Participants
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Number of Patients With Treatment-Related Adverse Events (AEs) as a Measure of Safety
|
16 Participants
|
SECONDARY outcome
Timeframe: After cycles 3 and 6 of each 21-day cycle, and every 3 months thereafter until progression or relapse from complete response for up to 40 monthsPopulation: All enrolled patients who have received study treatment.
Defined as the time from first treatment until objective tumor progression, relapse from complete response, or death from any cause. Tumor response is defined by the International Working Group (IMW)-revised response criteria for malignant lymphoma (Cheson 2007). This criteria categorizes the response of a patient's tumor to treatment as Complete Response (CR): the disappearance of all disease evidence; Partial Response (PR): regression of measurable disease and no new sites; Stable Disease (SD): less than a PR but not progressive disease (PD); Relapsed Disease or PD: Any new lesion or increase by ≥ 50% of previously involved sites from nadir. Patients who are alive and free from disease progression will be censored at the date of last tumor assessment.
Outcome measures
| Measure |
Bendamustine/Ofatumumab
n=21 Participants
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length).
Bendamustine: via IV infusion, 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 Ofatumumab: via IV infusion, 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6
|
|---|---|
|
Progression-free Survival
|
8.6 months
Interval 4.6 to 10.6
|
Adverse Events
Bendamustine/Ofatumumab
Serious adverse events
| Measure |
Bendamustine/Ofatumumab
n=21 participants at risk
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length). Patients will receive as an IV infusion of bendamustine Days 1 and 2 of Cycles 1-6, ofatumumab Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2-6 (see Figure 1).
Bendamustine: Patients will receive as an IV infusion bendamustine 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 and ofatumumab 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6(a cycle is defined as 21 days in length).
Ofatumumab: Patients will receive as an IV infusion bendamustine 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 and ofatumumab 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6(a cycle is defined as 21 days in length).
|
|---|---|
|
Vascular disorders
Pulmonary Embolism
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Vascular disorders
Deep Vein Thrombosis
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Infections and infestations
Pneumonia
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Gastrointestinal disorders
Abdominal distension
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Infections and infestations
Abdominal infection
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Renal and urinary disorders
Acute kidney injury
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Infections and infestations
Cystitis
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
General disorders
Death
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Metabolism and nutrition disorders
Dehydration
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Gastrointestinal disorders
Diarrhoea
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
General disorders
Disease progression
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Respiratory, thoracic and mediastinal disorders
Dyspnoea
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Injury, poisoning and procedural complications
Fall
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
General disorders
Fatigue
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Gastrointestinal disorders
Gastrointestinal necrosis
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Investigations
Haemoglobin decreased
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Investigations
Platelet count decreased
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Respiratory, thoracic and mediastinal disorders
Pulmonary embolism
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Nervous system disorders
Syncope
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Infections and infestations
Urinary tract infection
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Investigations
White blood cell count decreased
|
4.8%
1/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
Other adverse events
| Measure |
Bendamustine/Ofatumumab
n=21 participants at risk
All patients in this study will receive ofatumumab and bendamustine as an IV infusion for 6 cycles (a cycle is defined as 21 days in length). Patients will receive as an IV infusion of bendamustine Days 1 and 2 of Cycles 1-6, ofatumumab Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2-6 (see Figure 1).
Bendamustine: Patients will receive as an IV infusion bendamustine 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 and ofatumumab 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6(a cycle is defined as 21 days in length).
Ofatumumab: Patients will receive as an IV infusion bendamustine 90 mg/m\^2 Days 1 and 2 of Cycles 1 through 6 and ofatumumab 1000-mg IV Days 1 and 8 during Cycle 1 only and on Day 1 of Cycles 2 through 6(a cycle is defined as 21 days in length).
|
|---|---|
|
General disorders
Fatigue
|
47.6%
10/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Gastrointestinal disorders
Nausea
|
42.9%
9/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Respiratory, thoracic and mediastinal disorders
Cough
|
28.6%
6/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Gastrointestinal disorders
Diarrhoea
|
23.8%
5/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Blood and lymphatic system disorders
Anaemia
|
19.0%
4/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Gastrointestinal disorders
Constipation
|
19.0%
4/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Metabolism and nutrition disorders
Decreased Appetite
|
19.0%
4/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
General disorders
Infusion Related Reaction
|
19.0%
4/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Investigations
Weight Decreased
|
19.0%
4/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
General disorders
Oedema Peripheral
|
14.3%
3/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Skin and subcutaneous tissue disorders
Pruritus
|
14.3%
3/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Gastrointestinal disorders
Vomiting
|
14.3%
3/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
General disorders
Asthenia
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Cardiac disorders
Chest Pain
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Nervous system disorders
Headache
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Metabolism and nutrition disorders
Hypoglycaemia
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Metabolism and nutrition disorders
Hypokalaemia
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Vascular disorders
Hypotension
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Psychiatric disorders
Insomnia
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Blood and lymphatic system disorders
Neutropenia
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Investigations
Neutrophil Count Decreased
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Investigations
Platelet Count Decreased
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
|
Skin and subcutaneous tissue disorders
Urticaria
|
9.5%
2/21 • Collected once per week during cycle 1 and then collected once per month until 30 days after last treatment.
All patients who received at least one dose of protocol treatment are included in the safety analysis.
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee The sponsor can review/embargo results communications prior to public release for a period that is \>60 days but ≤180 days from date submitted to sponsor, who may require changes to the communication in order to remove specifically identified confidential information (other than study data) and/or delay the proposed publication to enable the sponsor to seek patent protection for inventions. The PI may not publish its results until 18 mos. after the trial has been completed at all sites.
- Publication restrictions are in place
Restriction type: OTHER