4CPS-202 Formulation of clobetasol and tacrolimus urethral syringes and efficacy in balanitis xerotica obliterans: a case report

<h3>Background and Importance</h3> Balanitis xerotica obliterans (BXO) is a chronic inflammatory disease that affects gland skin and the foreskin. It is characterised by sclerotic and atrophic lesions, leading to stenosis of the urethra. Pharmacological treatment consists in topical corticosteroids or calcineurin inhibitors. <h3>Aim and Objectives</h3> To describe the formulation of clobetasol and tacrolimus urethral syringes and to relate our experience in the treatment of BXO. <h3>Material and Methods</h3> A 12 year-old child operated for scrotal hypospadias, developed a BXO on foreskin donor skin. The urethral mucosa was sclerosed and whitish, with an atrophic aspect, and the basal flux was 5 ml/s. A bibliographical search was carried out (Pharmacopoeia and PubMed) about clobetasol and tacrolimus urethral syringes. Galenic validation included organoleptic characteristics evaluation and pH and microbiological control. Treatment efficacy was assessed by skin symptom resolution and increased voiding flow. <h3>Results</h3> Modus operandi for clobetasol 0.05% urethral syringe 3 mL in a laminar flow cabinet: Weigh 5.5 mg of clobetasol product. Add a small portion of urological lubricant (OneGel) and mix. Repeat step 2 to a total volume of 3 ml. Repack in an urethral syringe. For tacrolimus 0.03% urethral syringe, the same steps should be followed as above, weighing a quantity of 3.3 mg of tacrolimus product. The given expiry date was 30 days at ambient temperature and protected from light. Treatment with daily clobetasol was started and improved. At month +3, it was reduced to every 48 hours and a worsening was observed, resuming the daily regimen. At month+6, the patient was asymptomatic and voiding flow had recovered, so it was decided to alternate with tacrolimus. The number of days per week with medication decreased progressively, 2 days of clobetasol and 4 days of tacrolimus (at month+10) and 2 days of clobetasol and 3 days of tacrolimus (at month+13). When 15 months of treatment were reached, clobetasol was reduced to once weekly. The medication was well-tolerated and voiding flow was progressively increasing. <h3>Conclusion and Relevance</h3> Both magistral formulations were validated and proved to be effective in the treatment of BXO through resolution of symptoms and progress in urodynamic testing. <h3>References and/or Acknowledgements</h3> <h3>Conflict of Interest</h3> No conflict of interest