Objectives: On the assumption that interstitial cystitis (IC) is the result of a defective mucous lining of the bladder epithelium, a study was carried out to investigate the activity of hyaluronic acid (HA) in the treatment of IC. HA is an important glycosaminoglycan (GAG) present in all connective tissues, including the GAG layer of the vesical mucosa. It exhibits a variety of pharmacologic properties that enhance its appeal for the therapy of IC.
Methods: A total of 25 patients, with the characteristic picture of IC and refractory to other medical treatments, participated in a trial of HA. Patients received 40 mg of HA intravesically on a weekly basis for 4 weeks, then monthly. Response to therapy was evaluated by symptom score, voiding diaries, and visual analog scales.
Results: An initial positive (complete+partial) response of 56% at week 4 increased to 71% by week 12. This response was maintained until week 20; beyond week 24 there appears to be a moderate decrease in the effectiveness of the medication. There was no significant toxicity attributable to the presence of HA in the bladder.
Conclusions: The response of refractory IC patients to the intravesical administration of HA was gratifying. In the past, many therapies for IC that were initially considered promising failed the test of a controlled study. Further studies will establish the effectiveness of this particular preparation of HA in the treatment of IC.