Brimapitide: Research & Studies

Research Overview#

Brimapitide was evaluated in a comprehensive clinical program for acute sensorineural hearing loss. While both the Phase 2 and Phase 3 HEALOS trials failed to meet their primary endpoints in the overall study population, post-hoc analyses consistently identified a subgroup of patients with profound hearing loss who showed significant benefit. The program was discontinued in 2023 after the ASSENT Phase 3 trial was also terminated.

Phase 3 HEALOS Trial: Staecker et al. (PMID 31083077)#

The HEALOS trial was the largest prospective study of brimapitide, enrolling 256 patients across 51 European and Asian sites.

Study Design#

• Prospective, double-blind, randomized, placebo-controlled
• Patients aged 18-65 with acute unilateral ISSNHL within 72 hours of onset
• Mean hearing loss of 40 dB or greater with mean threshold of 60 dB or greater at the 3 worst affected frequencies
• Three arms: AM-111 0.4 mg/mL, AM-111 0.8 mg/mL, placebo gel
• Follow-up at days 3, 7, 28, and 91

Primary Endpoint Result#

The primary endpoint (hearing improvement from baseline to day 28) was not met in the overall study population.

Post-Hoc Subgroup Analysis#

In patients with profound ISSNHL (n=98), AM-111 0.4 mg/mL showed:

This 15.9 dB difference is clinically meaningful and represents a substantial improvement in functional hearing.

Phase 2 Trial: Suckfuell et al. (PMID 24979398)#

The Phase 2 trial established proof of concept and safety, identifying the severe-to-profound subgroup as the most responsive population. The drug and intratympanic administration procedure were well-tolerated.

Why the Program Failed#

The failure of brimapitide in the overall population may reflect the biology of JNK activation in the cochlea:

• JNK activation appears to be most pronounced following severe cochlear injury
• In milder cases of hearing loss, JNK-mediated apoptosis may not be the dominant mechanism
• The drug may have been tested in a population that was too heterogeneous
• A trial specifically enrolling only profound ISSNHL patients might have succeeded, but this was not pursued

Evidence Quality Assessment#

Research Evidence Context#

Brimapitide belongs to the Healing category of research peptides. The research evidence for Brimapitide spans multiple study types and endpoints. Researchers should evaluate the strength of evidence based on study design, sample size, and publication status when drawing conclusions about efficacy and safety.

Key Clinical Studies#

The following studies provide the clinical evidence base for Brimapitide:

Efficacy and Safety of AM-111 in the Treatment of Acute Unilateral Sudden Deafness - A Double-blind, Randomized, Placebo-controlled Phase 3 Study#

Authors: Staecker H, Jokovic G, Karpishchenko S, et al. (2019) — Otology and Neurotology

Phase 3 HEALOS trial evaluating single-dose intratympanic AM-111 (0.4 mg/mL or 0.8 mg/mL) versus placebo gel in 256 patients with acute unilateral ISSNHL presenting within 72 hours.

Key Findings:

• Primary endpoint not met in the overall study population
• Post-hoc analysis showed significant effect in profound ISSNHL subgroup (n=98)
• AM-111 0.4 mg/mL group showed 42.7 dB improvement versus 26.8 dB placebo in profound subgroup (p=0.0176)
• No drug-related serious adverse events reported

Limitations: Primary endpoint failed in the overall population. Post-hoc subgroup analysis requires prospective confirmation. Study enrolled heterogeneous hearing loss severity levels.

Efficacy and safety of AM-111 in the treatment of acute sensorineural hearing loss - a double-blind, randomized, placebo-controlled phase II study#

Authors: Suckfuell M, Lisowska G, Domka W, et al. (2014) — Otology and Neurotology

Phase 2 double-blind, randomized, placebo-controlled trial of AM-111 intratympanic injection in patients with acute sensorineural hearing loss.

Key Findings:

• Established proof of concept for AM-111 in severe-to-profound hearing loss
• Drug and administration procedure were well-tolerated
• JNK activation appears most relevant in cases with pronounced cochlear injury
• Primary endpoint not met in overall population but positive trend in severe subgroup

Limitations: Small sample size. Primary endpoint not met in overall population. Post-hoc subgroup analysis.

Evidence Quality Assessment#

The overall evidence level for Brimapitide is classified as moderate. There is meaningful clinical evidence from Phase 2 or similar trials, though larger confirmatory studies may be needed.

Research Gaps and Future Directions#

The following gaps in the current evidence base for Brimapitide have been identified:

• Prospective trial specifically in profound ISSNHL subpopulation (not conducted before discontinuation)
• Optimal treatment timing within the 72-hour window
• Combination with systemic corticosteroids (standard of care)
• Application to other forms of acute hearing loss (noise-induced, ototoxic)
• Duration of otoprotective effect beyond 91 days

Addressing these research gaps will be important for establishing a more complete understanding of Brimapitide's therapeutic potential and safety profile.

Related Reading#

• Brimapitide overview and research guide
• Brimapitide dosing protocols
• Brimapitide molecular structure