Prospective, randomized, double-blind study of safety and tolerability of intravesical resiniferatoxin (RTX) in interstitial cystitis (IC).
OBJECTIVE
To determine the safety and tolerability of intravesical resiniferatoxin (RTX) in interstitial cystitis (IC) patients.


METHODS
IC patients were instilled with 50 cc of test solution containing either placebo, 0.05 microM or 0.10 microM RTX in the bladder. Plasma concentration of RTX and its degradant resiniferonol 9-, 13-, 14-orthophenylacetate was measured. Immediate post-treatment blood sampling and cystoscopy were performed. Symptoms were evaluated before treatment, at 4- and at 12-week follow-ups, using VAS indicator for pain, voiding diary, and O'Leary's IC symptom/problem indices.


RESULTS
Among 22 patients observed (ten in 0.10 microM RTX, eight in 0.05 microM RTX, and four in placebo groups), the most commonly reported adverse event was pain during instillation (80.0%, 87.5%, and 25.0%). No serious adverse events were reported.


CONCLUSIONS
Use of intravesical RTX in IC patients is associated with important tolerability issues but safe at 0.10 microM and 0.05 microM.
Chen
Tony Y H
TY
Centre Hospitalier Universitaire de Sherbrooke, Service d'urologie 3001, Canada. tony.chen@mail.mcgill.ca
Corcos
Jacques
J
Camel
Michel
M
Ponsot
Yves
Y
Tu
Le Mai
le M
D000283:Administration, Intravesical; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018856:Cystitis, Interstitial / Q000188:drug therapy*; D003558:Cystoscopy; D004224:Diterpenes / Q000008:administration & dosage* / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009498:Neurotoxins / Q000008:administration & dosage* / Q000097:blood; D010147:Pain Measurement; D010919:Placebos; D011446:Prospective Studies; D012449:Safety; D014554:Urination / Q000187:drug effects
D004224:Diterpenes; D009498:Neurotoxins; D010919:Placebos; C487058:resiniferonol 9,13,14-ortho-phenylacetate; C024353:resiniferatoxin