Intratympanic drug injections for Tinnitus: What Does the Evidence Show?
Drugs & Pharmacology
Current evidence
Injections through the eardrum keep failing their controlled tests — the placebo response is doing the work.
Evidence strength: Weak (1/5) · Tier 5 — weak or unsupported · Evidence independence: Primarily sponsor-supported.
Steroids, lidocaine or experimental drugs injected through the eardrum into the middle ear. Two of the largest placebo-controlled programs in tinnitus history used this route — and both failed.
Did tinnitus loudness improve?
None shown. AM-101/TACTT2 failed its loudness endpoint; lidocaine's transient suppression lasts minutes and causes vertigo.
Did tinnitus distress improve?
None shown. OTO-313: placebo beat drug numerically (36% vs 26% TFI responders). TACTT3 (N=893) failed its TFI endpoint. Positive results come only from small trials without placebo arms.
Loudness means the tinnitus percept itself became quieter (psychoacoustic matching or loudness ratings). Distress means questionnaire scores such as THI/TFI, sleep, anxiety or quality of life improved — the sound may be unchanged. A THI/TFI improvement is never evidence the tinnitus got quieter.
How strong is the evidence?
The best-controlled data in the field are negative: 1/5, Tier 5.
Has the result been independently replicated?
None yet. Positive early signals not reproduced; Phase 3 program failed.
What are the limitations?
- Both large placebo-controlled programs failed
- 30–40% placebo responder rates explain the open-label 'wins'
What should patients know about safety?
Safety evidence: Limited. Eardrum perforation risk, pain, transient vertigo (especially lidocaine).
Is it available?
Regulatory status: Off-label (steroids); investigational (others). AAO-HNSF 2014 recommends against routine intratympanic drugs for tinnitus.
Availability: Offered off-label by some ENTs · Europe: Same · Cost (approx.): $300–1,500/injection
What the studies found
OTO-313 (intratympanic gacyclidine) Phase 2: negative trial
Searchfield GD, et al. · European Archives of Oto-Rhino-Laryngology · 2023 · N=153 · Randomized placebo-controlled Phase 2
FAILED: responders 26% (OTO-313) vs 36% (placebo), p=0.385 — placebo numerically better. Otonomy discontinued the program and subsequently dissolved.
One of the cleanest demonstrations of the ~30–40% placebo response that plagues tinnitus drug trials.
Keyzilen (AM-101) TACTT2 & TACTT3 Phase 3 failures (registry records)
Auris Medical (sponsor) · ClinicalTrials.gov posted results (no peer-reviewed Phase 3 publication exists) · 2018 · N=343 (TACTT2) + TACTT3 (NCT02040194) · Randomized placebo-controlled Phase 3 trials (intratympanic esketamine gel)
FAILED. TACTT2 posted results: loudness change 0.80 vs 0.63 placebo (p=0.32); TFI 10.4 vs 9.6 (p=0.63) — both endpoints failed. TACTT3 (NCT02040194) also missed its primary endpoint; results never posted or published. Sponsor exited otology (now Altamira Therapeutics).
Failed on both a loudness construct and a distress construct. That no Phase 3 results were ever peer-review published is itself informative.
Related treatments
- SPI-1005 (ebselen) — The most advanced drug with a tinnitus-relevant claim — but its trials are in Meniere's disease, and the…
- TRTL-913 (GABA-A modulator) — A new $106M bet that a GABA-A drug can quiet tinnitus — Phase 2 starts soon; no human tinnitus data yet.
- Off-label oral drugs (antidepressants, benzodiazepines, gabapentin, betahistine) — No drug is approved for tinnitus anywhere — and the systematic reviews say none of the usual suspects works…
- Supplements (ginkgo, zinc, melatonin…) — Heavily marketed, repeatedly tested, consistently unsupported.
Evidence last reviewed: 2026-09-03 · Evidence included through: 2026-09-03 · Confidence: high. Open the interactive evidence profile.
This page summarizes published research for education. It is not medical advice; it cannot say what will work for any individual. Discuss treatment decisions with a qualified clinician.