IMAAVY - Use in Combination with Corticosteroids in Patients with wAIHA

SUMMARY

• The company cannot recommend any practices, procedures, or usage of IMAAVY that deviate from the approved labeling.
• ENERGY is an ongoing, phase 2/3, multicenter, randomized, double-blind (DB), placebo (PBO)-controlled trial in adult patients with warm autoimmune hemolytic anemia (wAIHA).¹ 
  • The reduction in average daily prednisone use was 15.1%, 14.0%, and 3.9% in the IMAAVY 30 mg/kg intravenous (IV) every 4 weeks (Q4W), IMAAVY 15 mg/kg every 2 weeks (Q2W), and PBO Q2W groups, respectively.¹

CLINICAL DATA

Fattizzo et al (2026)¹ evaluated the efficacy and safety of IMAAVY in adults with wAIHA in a phase 2/3 multicenter, randomized, DB, PBO-controlled study.

Study Design/Methods

• The study included adults (≥18 years of age) diagnosed with primary or secondary wAIHA for ≥3 months, defined as having all of the following:^1,2 
  • Hemoglobin (Hgb) <10 g/dL
  • Signs of hemolysis (lactic dehydrogenase [LDH] >upper limit of normal [ULN], or indirect bilirubin >ULN, or haptoglobin [Hp] <lower limit of normal [LLN])
  • Direct antiglobulin test (DAT) positive for IgG+/-complement component 3d (C3d)
• The study consisted of a 2-week screening phase, followed by a 24-week, DB, PBO-controlled treatment phase, a 144-week open-label extension (OLE) phase, and safety follow-up at 8 weeks after the last infusion.¹ 
• Eligible patients were randomized (1:1:1) to receive IV IMAAVY 30 mg/kg Q4W, IMAAVY 15 mg/kg Q2W, or matching PBO Q2W through week 24.
  • Randomization was stratified by concurrent treatment for wAIHA (no treatment or receiving ≤20 mg/day prednisone equivalent without immunosuppressants vs receiving immunosuppressants or >20 mg/day of prednisone equivalent), primary or secondary wAIHA, and screening Hgb (≤8.5 or >8.5 g/dL).
• Efficacy analyses were performed using the full analysis set (all randomized patients excluding 3 patients randomized to receive IMAAVY 30 mg/kg Q2W, a regimen which was subsequently discontinued).
• The safety analysis population included all randomized patients who received any dose of study treatment, which included the 3 patients who received IMAAVY 30 mg/kg Q2W.
• The primary endpoint was the proportion of patients who achieved a durable Hgb response, defined as Hgb ≥10 g/dL and a ≥2 g/dL increase from baseline for 3 consecutive visits (≥28 days) starting by Week 16 without the need for rescue therapy.
• If patients were on corticosteroids, they had to be receiving the treatment for ≥4 weeks, with a stable dose during the screening period or for ≥14 days prior to randomization.² 
• A key secondary endpoint was percent reduction in the corticosteroid dose at week 24 in patients who received corticosteroids at baseline.
• Patients taking corticosteroids who met the primary endpoint were required to initiate steroid tapering (unless medically infeasible).
  • Doses were reduced by 10% of baseline dose Q2W and paused or reversed if Hgb decreased ≥1 g/dL.

Results

• A total of 118 patients were randomized to receive IMAAVY 30 mg/kg IV Q4W (n=38), IMAAVY 15 mg/kg IV Q2W (n=38), or PBO (n=39) through week 24.
• For baseline treatment details, see Table: Corticosteroid Use at Baseline.

Use of Corticosteroids

• A total of 8, 6, and 3 patients receiving IMAAVY 30 mg/kg IV Q4W, 15 mg/kg IV Q2W, and PBO, respectively, achieved the primary endpoint while on corticosteroids at baseline and were therefore required to taper their corticosteroid dose.
• Details of corticosteroid dose reduction from baseline to week 24 are discussed in Table: Corticosteroid Dose Reduction from Baseline to Week 24.

• The mean (SD) absolute prednisone-equivalent dose reduction was 3.7 (8.3), 2.5 (6.8), and 0.7 (2.7) mg for the IMAAVY 30 mg/kg Q4W, 15 mg/kg Q2W, and PBO groups, respectively.

Literature Search

A literature search of MEDLINE^®, EMBASE^®, BIOSIS Previews^®, and DERWENT^® (and/or other resources, including internal/external databases) was conducted on 31 August 2026.