Title

Safety and Efficacy Study of Repeated Doses of DX-88 (Ecallantide) to Treat Attacks of Hereditary Angioedema (HAE)
Open-label Patient Continuation of DX-88 (Ecallantide) for Acute Hereditary Angioedema Attacks
  • Phase

    Phase 3
  • Study Type

    Interventional
  • Study Participants

    147
The purpose of this study is to evaluate the efficacy and safety of repeated doses of ecallantide in the treatment of acute attacks of hereditary angioedema and to allow HAE patients continued access to ecallantide. In addition, patients enrolled in DX-88/20 (EDEMA4) trial will be followed up and treated for subsequent attacks in this trial.
This is an open label trial.

The study is designed to assess the efficacy and safety of 30 mg subcutaneous ecallantide in the treatment of acute attacks of hereditary angioedema. This study is designed to provide efficacy and safety data on repeated use of ecallantide. These data are intended to support the marketing authorization of ecallantide in the treatment of acute attacks of hereditary angioedema. Efficacy and safety of ecallantide will be evaluated in this study.
Study Started
Apr 01
2007
Primary Completion
Jun 01
2010
Study Completion
Sep 01
2010
Results Posted
Dec 28
2012
Estimate
Last Update
Jun 08
2021

Drug ecallantide

solution for SC injection, one 30 mg dose per HAE attack

  • Other names: DX-88

DX-88 (ecallantide) Experimental

DX-88 (ecallantide) Patients were treated with DX-88 (ecallantide) when they experienced an HAE attack. 30 mg dose of ecallantide given via 3 SC injections; a second 30 mg dose can be administered if needed. Patients were to be assessed until 4 hrs post-dose. Patients were asked to return for 3 follow-up visits: 7 days, 28 days and 90 days post-dose.

Criteria

Inclusion Criteria:

10 years of age or older
Documented diagnosis of HAE (Type I or II)
Willing and able to give informed consent
Acute HAE attack at time of presentation

Exclusion Criteria:

Receipt of an investigational drug or device, within 30 days prior to study treatment, other than DX-88 (ecallantide)
Pregnancy or breastfeeding
Receipt of non-investigational C1-INH or DX-88 within 72 hours of treatment
Patients eligible for current, ongoing clinical trial in which DX 88 (ecallantide) is offered

Summary

Treatment

All Events

Event Type Organ System Event Term Treatment

Change From Baseline in Mean Symptom Complex Severity (MSCS) Score at 4 Hrs Post Dosing

Mean Symptom Complex Severity (MSCS) score is a validated point-in-time measure of symptom severity. At baseline and 4 hrs, patients rated the severity on a categorical scale (0=normal, 1=mild, 2=moderate, 3=severe) for symptoms at each affected anatomical location. Ratings were averaged to obtain the MSCS score. A decrease in MSCS score reflected an improvement in symptoms; clinically meaningful improvement was indicated by a reduction in the score of 0.30 or more.

DX-88 (Ecallantide)

change in MSCS at 4 hrs episode 10 (n=16)

-1.27
scores on a scale (Mean)
Standard Deviation: 1.027

change in MSCS at 4 hrs episode 11 (n=16)

-1.22
scores on a scale (Mean)
Standard Deviation: 0.643

change in MSCS at 4 hrs episode 12 (n=12)

-1.36
scores on a scale (Mean)
Standard Deviation: 0.677

change in MSCS at 4 hrs episode 13 (n=12)

-1.1
scores on a scale (Mean)
Standard Deviation: 0.657

change in MSCS at 4 hrs episode 1 (n=138)

-1.04
scores on a scale (Mean)
Standard Deviation: 0.773

change in MSCS at 4 hrs episode 2 (n=98)

-1.06
scores on a scale (Mean)
Standard Deviation: 0.731

change in MSCS at 4 hrs episode 3 (n=73)

-1.07
scores on a scale (Mean)
Standard Deviation: 0.801

change in MSCS at 4 hrs episode 4 (n=52)

-1.15
scores on a scale (Mean)
Standard Deviation: 0.791

change in MSCS at 4 hrs episode 5 (n=38)

-1.16
scores on a scale (Mean)
Standard Deviation: 0.746

change in MSCS at 4 hrs episode 6 (n=32)

-1.07
scores on a scale (Mean)
Standard Deviation: 0.806

change in MSCS at 4 hrs episode 7 (n=25)

-1.24
scores on a scale (Mean)
Standard Deviation: 0.797

change in MSCS at 4 hrs episode 8 (n=22)

-1.31
scores on a scale (Mean)
Standard Deviation: 0.667

change in MSCS at 4 hrs episode 9 (n=22)

-1.2
scores on a scale (Mean)
Standard Deviation: 0.764

Treatment Outcome Score (TOS) at 4 Hrs Post Dosing, Based on the Patient Assessment of Baseline Severity of Symptoms

The Treatment Outcome Score (TOS)is a validated measure of response to therapy. Response assessment for each symptom complex (internal head/neck, stomach/GI, genital/buttocks, external head/neck or cutaneous) was to be weighted based on the severity of symptom complexes at baseline. Severity assessment at baseline was rated on a categorical scale (1=mild, 2=moderate, 3=severe) for symptoms at each affected symptom complex. Response assessment of each symptom complex post-dosing relative to baseline used a scale (100=significant improvement, 50=improvement, 0=same). The weighted values were used to calculate the composite TOS. A TOS greater than 0 denotes an improvement in symptoms compared with baseline severity.

DX-88 (Ecallantide)

TOS at 4 hrs for episode 10 (n=16)

76.3
scores on a scale (Mean)
Standard Deviation: 23.556

TOS at 4 hrs for episode 11 (n=16)

60.94
scores on a scale (Mean)
Standard Deviation: 45.615

TOS at 4 hrs for episode 12 (n=13)

76.92
scores on a scale (Mean)
Standard Deviation: 43.853

TOS at 4 hrs for episode 13 (n=12)

64.93
scores on a scale (Mean)
Standard Deviation: 46.854

TOS at 4 hrs for episode 1 (n=140)

69.8
scores on a scale (Mean)
Standard Deviation: 35.378

TOS at 4 hrs for episode 2 (n=98)

70.05
scores on a scale (Mean)
Standard Deviation: 40.639

TOS at 4 hrs for episode 3 (n=73)

63.08
scores on a scale (Mean)
Standard Deviation: 42.840

TOS at 4 hrs for episode 4 (n=52)

62.65
scores on a scale (Mean)
Standard Deviation: 42.802

TOS at 4 hrs for episode 5 (n=39)

65.13
scores on a scale (Mean)
Standard Deviation: 34.858

TOS at 4 hrs for episode 6 (n=32)

60.42
scores on a scale (Mean)
Standard Deviation: 40.866

TOS at 4 hrs for episode 7 (n=25)

56.2
scores on a scale (Mean)
Standard Deviation: 34.229

TOS at 4 hrs for episode 8 (n=22)

79.77
scores on a scale (Mean)
Standard Deviation: 24.663

TOS at 4 hrs for episode 9 (n=22)

71.06
scores on a scale (Mean)
Standard Deviation: 37.270

Time to Significant Improvement

Time to significant improvement in overall response based on the period from 15 minutes after dosing through 4 hrs post dosing. Significant improvement was defined as a response of "a lot better or resolved" in the overall response assessment.

DX-88 (Ecallantide)

time to improvement in min. for episode 10 (n=17)

170.5
estimated time in minutes (Median)
95% Confidence Interval: 165.1

time to improvement in min. for episode 11 (n=16)

226.5
estimated time in minutes (Median)
95% Confidence Interval: 145.7

time to improvement in min. for episode 12 (n=15)

177.2
estimated time in minutes (Median)
95% Confidence Interval: 113.8

time to improvement in min. for episode 13 (n=13)

195.2
estimated time in minutes (Median)
95% Confidence Interval: 135.1

time to improvement in min. for episode 1 (n=145)

225.2
estimated time in minutes (Median)
95% Confidence Interval: 165.4 to 228.2

time to improvement in min. for episode 2 (n=102)

194.5
estimated time in minutes (Median)
95% Confidence Interval: 165.2 to 227.5

time to improvement in min. for episode 3 (n=77)

225.4
estimated time in minutes (Median)
95% Confidence Interval: 225.1

time to improvement in min. for episode 4 (n=56)

198.1
estimated time in minutes (Median)
95% Confidence Interval: 165.4

time to improvement in min. for episode 5 (n=41)

240.0
estimated time in minutes (Median)
95% Confidence Interval: 165.3

time to improvement in min. for episode 6 (n=33)

225.2
estimated time in minutes (Median)
95% Confidence Interval: 137.0

time to improvement in min. for episode 7 (n=27)

time to improvement in min. for episode 8 (n=23)

210.5
estimated time in minutes (Median)
95% Confidence Interval: 135.3

time to improvement in min. for episode 9 (n=23)

169.3
estimated time in minutes (Median)
95% Confidence Interval: 135.4 to 240.0

Age, Continuous

35.8
years (Mean)
Standard Deviation: 14.39

Region of Enrollment

Sex: Female, Male

Overall Study

DX-88 (Ecallantide)