New approaches to instillation therapy for IC are being tried and tested, with a focus on longer-term results or even healing rather than “rescue.” These include:

PSD597 (Plethora Solutions)

This is the formulation of alkalinized lidocaine used in the clinical trial published earlier this year. It includes a delivery system and a proprietary formulation said to protect the active drug in the bladder and ensure that the drug remains in the optimal chemical form for transport across the bladder wall to its site of action.

URG101 (Urigen)

This is a formulation of alkalinized lidocaine and heparin for instillation. Interim analysis of a phase 2 trial showed significant improvement in average daytime pain, daytime urgency, and symptom score.

Uracyst (Stellar Pharmaceuticals)

This formulation of sterile sodium chondroitin sulfate solution (2.0%) is approved for marketing in Canada and Europe. It is thought to replace the damaged glycosaminoglycan layer of the bladder. In an uncontrolled, six-week Canadian trial in 53 patients with moderately severe IC received weekly instillations for six weeks, then monthly over 16 weeks for a total of 10 treatments. At 10 and 24 weeks, symptom and bother scores were significantly reduced.

Liposomes for instillation (Lipella)

The first human trial of liposomes for instillation was published online in August 2009 (Chuang YC et al. J Urol. 2009;182:1393-1400). In this small trial, liposomes instilled once a week for four weeks were compared with oral pentosan polysulfate (Elmiron) 100 mg three times a day for four weeks. Both reduced frequency and nocturia significantly, but patients who received liposomes also had significant decreases in pain, urgency, and O’Leary-Sant symptom scores.

Misoprostol (Cytotec) for instillation

This prostaglandin E1 analog is used orally to reduce the risk of NSAID-induced gastric ulcers. NSAIDs interfere with the NF-kappa B signaling pathway prevent production of prostaglandins. Because this pathway is damaged in IC cells, Raymond Rackley, MD, at the Cleveland Clinic, theorized that this drug may help heal IC bladder lining. It is being used experimentally only in patients with severe IC for whom treatments short of surgery have failed.

Revised Monday, June 12th, 0220