10,11 Liposomal delivery of chemotherapeutic agents allows prolonged duration of action and reduced toxicity profile.12,13 The success of liposomes in the clinic has been attributed to the nontoxic nature of the lipids used in their formulation. The Dynasore concentration phospholipids composing empty liposomes themselves have been found to have pharmacological effects, which

may explain their use as a topical healing agent in the treatment of dry eye.14,15 Existing therapy options for IC/PBS fail to completely address the significant bladder inflammation associated with IC/PBS. Local anesthetics like lidocaine, when used alone, can provide only short-term symptom relief by blocking the conduction from sensory Inhibitors,research,lifescience,medical nerves in the bladder without affecting the underlying bladder inflammation. Recently, Chuang and colleagues assessed the clinical safety and efficacy of liposomes instilled Inhibitors,research,lifescience,medical in IC/PBS patients.16 An open-label, active comparator, prospective study compared the effect of intravesical liposomes against oral pentosan polysulfate sodium (PPS) on 24 IC/PBS patients. Patients divided into the 2 treatment arms each received either intravesical liposomes (80 mg/40 cc distilled water) once weekly or oral pentosan polysulfate sodium (100 mg) thrice daily for 4 weeks. Response to treatment was assessed by 10 measures at 4 and 8 weeks relative to baseline. Inhibitors,research,lifescience,medical Both liposomes

Inhibitors,research,lifescience,medical and oral PPS significantly decreased the urinary frequency and nocturia to indicate comparable efficacy of liposomes. Urgency was profoundly reduced in the liposome group accompanied by significant decreases in pain and the O’Leary-Sant symptom score. There were no reports of urinary incontinence, retention, or infection due to liposome instillation, and there were no unanticipated adverse events and no significant worsening of symptoms during follow-up. Inhibitors,research,lifescience,medical Intravesical instillation of liposomes was found to be safe for IC/PBS with potential improvement after a single course of therapy for up to 8 weeks. The results

support liposomes as a promising new treatment of IC/PBS, and future large-scale, almost placebo-controlled studies are needed to confirm these results. The MOA for liposomes in IC/PBS bladder require mechanistic studies but a liposomal coating affording protection of urothelium from urine cannot be ruled out (Figure 1). Adherence of liposomes as tightly packed bilayers on bladder surface can contribute to the barrier property of the bladder. In addition, liposomes composed of bioactive lipids can exert anti-inflammatory effects by initiating local lipid signaling and affecting mast cell activity17,18 (Figure 1). Figure 1 The phospholipids of instilled liposomes have an innate affinity for lipids in cells lining the bladder surface, which facilitate the formation of a protective coating on the injured bladder lumen surface and help protect inflamed uroepithelium.