a multicenter, double-blind, placebo-controlled study in patients with Sudden Sensorineural Hearing Loss (SSHL). Patients will be treated with STR001 thermogel (STR001-IT) / STR001 tablets (STR001-ER) and corresponding Placebo on top of standard of care.

Inclusion Criteria:

1. Male or female patients aged ≥ 18

2. Patients with a SSHL within 96 hours of its perception

3. Sudden Sensorineural Hearing Loss including

   1. idiopathic unilateral Sudden Sensorineural Hearing Loss or
   2. acute uni- or bilateral acoustic trauma-induced Sudden Sensorineural Hearing Loss

Exclusion Criteria:

1. Patients with a history of Meniere's Disease
2. Patients with a hearing threshold above 100 dB across at least 6 frequencies
3. Patients with endolymphatic, hydrops or history of fluctuating hearing loss
4. Patients with suspected perilymph fistula, membrane rupture, retrocochlear lesions or a barotrauma
5. Patients with an air-bone gap of ≥ 20 dB in 3 contiguous frequencies at baseline
6. Previous SSHL incident at the same ear
7. Patients with acute or chronic otitis media or otitis externa.
8. Patients with congenital hearing loss
9. Patients with known hypersensitivity to pioglitazone, other thiazolidindiones or any formulation component
10. Use of thiazolidinedione (e.g. pioglitazone, rosiglitazone) in the last 6 months prior to baseline
11. Any use of CYP450 2C8 inducers (e.g. rifampicine)
12. Fibrates (e.g. gemfibrozil, fenofibrate) in the last 6 months prior to baseline
13. Patients where oral administration of pioglitazone is contraindicated (i.e. cardiac failure or history of cardiac failure (NYHA stages I to IV), hepatic impairment, diabetic ketoacidosis, current bladder cancer or a history of bladder cancer, uninvestigated macroscopic haematuria
14. Women who are breastfeeding, pregnant or plan to get pregnant during the trial duration
15. Women of childbearing potential unwilling or unable to practice effective method of contraception
16. Participation in other clinical trials in the last month prior to baseline

double-blind